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Developing Dynamic Web Applications with MySQL and PHP Revision 1.4
PRESENTED BY
MYSQL AB TRAINING SERVICES
[email protected] http://www.mysql.com/training/ INSTRUCTOR GUIDE
DBA
Developer
Support
Consulting
Developing Web Applications with MySQL and PHP
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1.3 MySQL Partners
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1.4 Supported Operating Services
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1.5 MySQL Certification Program
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1.6 Training Curriculum Paths
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1.7 MySQL Website
Chapter
Course/Chapter/Section Name
Duration (Hours)
PHP and MySQL
26.5
Day One 1 Introduction 1.1 Structure of MySQL AB 1.2 MySQL Products and Services
Track
7.5
0.25
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2 Verify Installation
3.25
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2.1 LAMP Architecture
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2.2 Install/Verify Apache Installation
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2.3 Install/Verify MySQL Installation
0.75
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2.4 Install/Verify PHP Installation
0.75
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2.5 Putting it All Together
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3 PHP Foundations
3.25
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3.1 Delimit PHP Code Within HTML
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3.2 Comment PHP Code
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3.3 Construct PHP that interacts with end users
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3.4 Data Types in PHP
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3.5 Key Control Systems
0.75
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3.6 Use Defined Functions
0.75
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Day Two 4 MySQL Foundations
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4.2 SQL Parser and Storage Engine Tiers
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4.3 MySQL Client
0.5
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4.4 MySQL Query Browser
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5 Manage Databases
1.25
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5.2 Database Design Practices
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5.3 MySQL Identifiers
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5.4 Create Databases
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5.5 Alter Databases
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5.6 Drop Databases
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6 Manage Tables
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6.2 MySQL Data Types
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6.3 Create Table
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6.4 Alter Table
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6.5 Empty Table
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6.7 Indexes
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6.8 Foreign Keys
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7.1 SELECT Statements
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7.2 Aggregating Query Results
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8.1 SQL Expressions
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8.2 Functions in SQL Expressions
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4.1 General Architecture
5.1 Database Properties
6.1 Table Properties
6.6 Remove Table
7 SQL SELECT Commands
8 SQL Expressions
Day Three 9 SQL DML Commands
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9.1 INSERT Statement
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9.2 DELETE Statement
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9.3 UPDATE Statement
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9.4 REPLACE Statement
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10 SQL Joins
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10.1 What is a Join
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10.2 Inner Joins
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10.3 Outer Joins
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10.4 Using Quaifiers and Aliases
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Comments
Owner
Developing Web Applications with MySQL and PHP 10.5 Multiple Table UPDATE and DELETE Statements
0.25
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11 MySQL Database Driven Web Based Forms
3.75
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11.1 Connecting to MySQL 11.2 Retrieving Data
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11.3 Inserting Data
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11.4 Updating Existing Data
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11.5 Deleting Data
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11.6 MySQL Metadata
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11.7 MySQL Error Information
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Day Four 12 Session Handling
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12.1 What is Session Handling
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12.2 Session Handling Tasks
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13.1 Benefits of OOP
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13.2 Working with Objects
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13.3 Exception Handling
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14.1 HTTP Authentication
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14.2 PHP Authentication
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12.3 PHP Session Handling with MySQL 13 Object Oriented Programming
14 Authentication
15 Securing PHP & MySQL 15.1 PHP Configuration Parameters
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15.2 Data Encryption
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15.3 Securing the MySQL Server
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15.4 Privileges
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16 Conclusion 16.1 Course Overview
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16.2 MySQL System Overview
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16.3 Training and Certification Website
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16.4 Course Evaluation
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16.5 Thank You! 16.6 Q&A Session
NOTES: Using Scale of 0-5 on Importance (0-not needed, 5-high) A duration of zero (0) means that the section should take less than 15 minutes (from 5 to 14) . Some section/chapter durations are padded to adjust for zero durations as well as for labs quizzes, further practices and breaks. Lunch breaks areNOT accounted for in this schedule.
Developing Dynamic Web Applications with MySQL and PHP
Developing Dynamic Web Applications with MySQL and PHP Training Guide This is the training guide for the Developing Dynamic Web Applications with MySQL and PHP training course. This training guide was developed using the MySQL 5.0 Community Edition - Generally Available (GA) Release and MySQL 5.1 Community Edition - Beta Release. MySQL AB would like to thank the many individuals that played a part in bringing this training material to the numerous students who will benefit from the knowledge and effort that each of these contributors put into the training. Even though there were a large number of contributions from many MySQL AB personnel, the following list of contributors played a vital role in developing this material and ensuring that its contents were accurate, timely and most of all presented in a way that would benefit those that are utilizing it for the benefit of improving their skills with MySQL. Max Mether, Course Development Manager Jeffrey Gorton, Course Developer and Editor Tom Hanlon, Subject Matter Expert Developing Dynamic Web Applications with MySQL and PHP Training Guide Copyright © 2007 by MySQL AB All rights reserved. No part of this training guide shall be reproduced, stored in a retrieval system, or transmitted by any means, electronic, mechanical, photocopying, recording, or otherwise, without the written permission of MySQL AB. No patent liability is assumed with respect to the use of the information contained herein. Although every precaution has been taken in the preparation of this training guide, MySQL AB and the associated contributors assume no responsibility for errors or omissions. Nor is any liability assumed for damages resulting from the use of the information contained herein. First Printing: May 2007 Trademarks The copyright to this training guide is owned by the Swedish company MySQL AB. MySQL® and the MySQL logo are registered trademarks of MySQL AB. Other trademarks and registered trademarks referred to in this manual are the property of their respective owners, and are used for identification purposes only. Warning and Disclaimers Every effort has been made to make this training guide as complete and accurate as possible to meet the needs of the training herein, but no warranty or fitness is implied. The information provided is on an “as is” basis.
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Developing Dynamic Web Applications with MySQL and PHP
Worldwide Office Locations and Contact Information
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Developing Dynamic Web Applications with MySQL and PHP
Conventions Used in This Training Guide This training guide uses certain typographical conventions: • TEXT IN THIS STYLE is used for SQL statements; database, table, and column names; program listings and source code; and environment variables. Example: “To reload the grant tables, use the FLUSH PRIVILEGES statement.” • Text in this style indicates input that you type in examples. • Text in this style indicates the names of executable programs and scripts, examples being mysql (the MySQL command line client program) and mysqld (the MySQL server executable). • Text in this style is used for variable input for which you should substitute a value of your own choosing. • Filenames and directory names are written like this: “The global my.cnf file is located in the /etc directory.” • Character sequences are written like this: “To specify a wildcard, use the '%' character.” • Text in this style is used for emphasis. • Text in this style is used in table headings and to convey especially strong emphasis. When commands are shown that are meant to be executed from within a particular program, the prompt shown preceding the command indicates which command to use. For example, shell> indicates a command that you execute from your login shell, and mysql> indicates a statement that you execute from the mysql client program: shell> type a shell command here mysql> type a mysql statement here The “shell” is your command interpreter. On Unix, this is typically a program such as sh, csh, or bash. On Windows, the equivalent program is command.com or cmd.exe, typically run in a console window. When you enter a command or statement shown in an example, do not type the prompt shown in the example. Database, table, and column names must often be substituted into statements. To indicate that such substitution is necessary, this manual uses db_name, tbl_name, and col_name. For example, you might see a statement like this: mysql> SELECT col_name FROM db_name.tbl_name; This means that if you were to enter a similar statement, you would supply your own database, table, and column names, perhaps like this: mysql> SELECT author_name FROM biblio_db.author_list; SQL keywords are not case sensitive and may be written in any lettercase. This training guide uses uppercase. In syntax descriptions, square brackets ('[' and ']') indicate optional words or clauses. For example, in the following statement, IF EXISTS is optional: DROP TABLE [IF EXISTS] tbl_name When a syntax element consists of a number of alternatives, the alternatives are separated by vertical bars ('|'). When one member from a set of choices may be chosen, the alternatives are listed within square brackets ('[' and ']'): TRIM([[BOTH | LEADING | TRAILING] [remstr] FROM] str) When one member from a set of choices must be chosen, the alternatives are listed within braces ('{' and '}'): {DESCRIBE | DESC} tbl_name [col_name | wild] An ellipsis (...) indicates the omission of a section of a statement, typically to provide a shorter version of more complex syntax. For example, INSERT ... SELECT is shorthand for the form of INSERT statement that is followed by a SELECT statement. An ellipsis can also indicate that the preceding syntax element of a statement may be repeated. In the following example, multiple reset_option values may be given, with each of those after the first preceded by commas: RESET reset_option [,reset_option] ... Commands for setting shell variables are shown using Bourne shell syntax. For example, the sequence to set the CC environment variable and run the configure command looks like this in Bourne shell syntax: shell> CC=gcc ./configure If you are using csh or tcsh, you must issue commands somewhat differently: shell> setenv CC gcc and shell> ./configure
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Developing Dynamic Web Applications with MySQL and PHP
Supporting Images Used in This Training Guide The following is a summary of the standard images used in this manual to support the instruction: IMAGE
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Written Exam
This image is used to identify that the student is going to be tested upon the material previously presented in the instructional material.
InLine Lab
Throughout the course the instructor will conduct labs in line with the instruction, which are designed to help you to understand the “nuts and bolts” (inner-workings) of the topic.
Further Practice Lab
This image is used to convey to the student that there is a final exercise to complete prior to the completion of the chapter.
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Instructor Notes: Boxes like this one are used throughout the course manual to give instructors tips on how to deliver the material and to give them extra information that is not included in the student manual. Please be advised that instructors are requested to cover all the material in this manual, as prompted by the slides. Although some slides will mimic the manual exactly, most will not. In those cases, instructors will need to use the manual, along with these notes to deliver the required information to the students. These note boxes will always be placed at the bottom of the page, and are only in the instructor guide.
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Developing Dynamic Web Applications with MySQL and PHP 2
COURSE OBJECTIVES This instructor-led course is designed for students planning on developing applications that make use of MySQL and PHP. Through a hands-on approach, this course will help developers with a reasonable knowledge of PHP improve their development skills to the point where they can use PHP and MySQL as a cohesive platform for the development of complex dynamic web applications. Upon completion of this course you will be able to: • Verify the correct installation of the LAMP Components • Utilize the basic components of PHP to build a foundation for more complex web applications • Understand the basic components of MySQL to build a foundation for the development of fully dynamic and database-driven sites • Manage Databases within MySQL • Manage Tables within MySQL • Utilize SQL query commands to retrieve data from the MySQL Database • Utilize SQL expressions • Manipulate table data using the SQL Data Manipulation Language (DML) commands • Retrieve data from multiple MySQL tables using Joins
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• Create web based forms that interact with the end user and the data within MySQL • Utilize session handling within PHP to track user-specific behavior and preferences. • Utilize error and exception handling in PHP to detect, log and report issues that may arise during program execution • Integrate PHP's object oriented programming (OOP) functionality into the design of web applications • Authenticate user identities utilizing PHP built-in authentication capabilities and MySQL's user and privilege management capabilities • Securing PHP and MySQL to improve the integrity of the application and subsequent data
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Developing Dynamic Web Applications with MySQL and PHP
Table of Contents 1
Introduction ....................................................................................................................................................... 1-1 1.1 Learning Objectives................................................................................................................................... 1-1 1.2 MySQL AB................................................................................................................................................ 1-2 1.3 MySQL Products ....................................................................................................................................... 1-3 1.3.1 MySQL Database Products................................................................................................................ 1-3 1.3.2 MySQL GUI Tools ............................................................................................................................ 1-5 1.3.3 MySQL Drivers ................................................................................................................................. 1-5 1.4 MySQL Services........................................................................................................................................ 1-6 1.4.1 MySQL Training ............................................................................................................................... 1-6 1.4.2 MySQL Certification ......................................................................................................................... 1-6 1.4.3 MySQL Consulting............................................................................................................................ 1-6 1.4.4 MySQL Support................................................................................................................................. 1-6 1.5 Community vs. Enterprise ......................................................................................................................... 1-7 1.6 MySQL Partners ........................................................................................................................................ 1-9 1.7 Supported Operating Systems...................................................................................................................1-10 1.8 MySQL Certification Program .................................................................................................................1-11 1.9 Training Curriculum Paths........................................................................................................................1-12 1.10 MySQL Website .......................................................................................................................................1-14 1.10.1 MySQL Community Web Page ........................................................................................................1-15 1.11 Chapter Summary .....................................................................................................................................1-18 2 LAMP ................................................................................................................................................................ 2-2 2.1 Learning Objectives................................................................................................................................... 2-2 2.2 LAMP Architecture ................................................................................................................................... 2-3 2.3 Apache Server............................................................................................................................................ 2-4 2.4 MySQL Server........................................................................................................................................... 2-8 2.5 PHP...........................................................................................................................................................2-12 2.6 Putting It All Together..............................................................................................................................2-16 2.7 Chapter Summary .....................................................................................................................................2-19 3 PHP FOUNDATIONS ............................................................................................................................................ 3-1 3.1 Learning Objectives................................................................................................................................... 3-1 3.2 Delimiting PHP Code ................................................................................................................................ 3-2 3.3 Comments.................................................................................................................................................. 3-3 3.4 Construct Feedback ................................................................................................................................... 3-5 3.5 PHP Data Types......................................................................................................................................... 3-7 3.5.1 Scalar Data Types .............................................................................................................................. 3-7 3.5.2 Compound Data Types ...................................................................................................................... 3-9 3.5.3 Special Data Types ...........................................................................................................................3-11 3.6 Flow Control Statements ..........................................................................................................................3-12 3.6.1 if ... else ... elseif ...............................................................................................................................3-13 3.6.2 Switch ...............................................................................................................................................3-15 3.6.3 While ................................................................................................................................................3-16 3.6.4 Do ... While.......................................................................................................................................3-16 3.6.5 For.....................................................................................................................................................3-17 3.6.6 Foreach .............................................................................................................................................3-18 3.6.6.1 Break and Continue ......................................................................................................................3-19 3.7 User Defined Functions ............................................................................................................................3-20 3.8 Chapter Summary .....................................................................................................................................3-22 4 MYSQL FOUNDATIONS ...................................................................................................................................... 4-1 4.1 Learning Objectives................................................................................................................................... 4-1 4.2 MySQL General Architecture.................................................................................................................... 4-2 4.2.1 MySQL Server................................................................................................................................... 4-2 4.2.2 Client Programs ................................................................................................................................. 4-2 4.3 SQL Parser and Storage Engine Tiers ....................................................................................................... 4-4 4.3.1 Storage Engine Breakdown ............................................................................................................... 4-5
Developing Dynamic Web Applications with MySQL and PHP
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The mysql Client ..................................................................................................................................... 4-6 4.4 4.4.1 Using mysql Interactively................................................................................................................ 4-6 4.4.2 Statement Terminators....................................................................................................................... 4-7 4.5 MySQL Query Browser............................................................................................................................. 4-9 4.5.1 Using the Connection Dialog............................................................................................................. 4-9 4.5.2 The MySQL Query Browser Window ..............................................................................................4-10 4.6 Chapter Summary .....................................................................................................................................4-13 MANAGING DATABASES ..................................................................................................................................... 5-1 5.1 Learning Objectives................................................................................................................................... 5-1 5.2 Database Properties ................................................................................................................................... 5-2 5.3 Database Design Practices ......................................................................................................................... 5-4 5.4 MySQL Identifiers..................................................................................................................................... 5-5 5.5 Creating Databases .................................................................................................................................... 5-6 5.6 Drop a Database......................................................................................................................................... 5-7 5.6.1 CAUTION: When Using DROP DATABASE.................................................................................. 5-7 5.7 Chapter Summary .....................................................................................................................................5-11 MANAGING DATABASE TABLES ......................................................................................................................... 6-1 6.1 Learning Objectives................................................................................................................................... 6-1 6.2 Table Properties ......................................................................................................................................... 6-2 6.2.1 Storage Engines ................................................................................................................................. 6-3 6.3 MySQL Data Types................................................................................................................................... 6-5 6.3.1 Numeric Data Type............................................................................................................................ 6-6 6.3.2 String Data Types .............................................................................................................................. 6-8 6.3.3 Temporal Data Types......................................................................................................................... 6-9 6.4 Creating Database Tables .........................................................................................................................6-10 6.4.1 Displaying Table Creation Information ............................................................................................6-11 6.4.2 Table Properties ................................................................................................................................6-12 6.4.3 Column Options................................................................................................................................6-13 6.4.4 Temporary Tables .............................................................................................................................6-14 6.5 Altering Tables .........................................................................................................................................6-15 6.5.1 Add Columns ....................................................................................................................................6-15 6.5.2 Remove Columns..............................................................................................................................6-16 6.5.3 Modifying Columns..........................................................................................................................6-16 6.5.4 Changing Columns ...........................................................................................................................6-17 6.5.5 Renaming Tables ..............................................................................................................................6-17 6.5.6 Emptying Tables ...............................................................................................................................6-17 6.6 Drop Tables ..............................................................................................................................................6-18 6.7 Table Indexing ..........................................................................................................................................6-19 6.8 Foreign Keys.............................................................................................................................................6-21 6.9 Chapter Summary .....................................................................................................................................6-30 SQL SELECT COMMANDS ................................................................................................................................... 7-1 7.1 Learning Objectives................................................................................................................................... 7-1 7.2 SELECT Statements .................................................................................................................................. 7-2 7.2.1 SELECT with DISTINCT ................................................................................................................. 7-4 7.2.2 SELECT with WHERE ..................................................................................................................... 7-6 7.2.3 SELECT with ORDER BY................................................................................................................ 7-8 7.2.4 SELECT with LIMIT........................................................................................................................7-10 7.2.5 SELECT with MySQL Query Browser ............................................................................................7-12 7.3 Aggregating Query Results.......................................................................................................................7-13 7.4 Chapter Summary .....................................................................................................................................7-18 SQL EXPRESSIONS ............................................................................................................................................. 8-1 8.1 Learning Objectives................................................................................................................................... 8-1 8.2 SQL Expressions ....................................................................................................................................... 8-2 8.2.1 Numeric Expressions ......................................................................................................................... 8-3 8.2.2 String Expressions ............................................................................................................................. 8-4 8.2.3 Temporal Expressions........................................................................................................................ 8-7 8.3 Functions in SQL Expressions................................................................................................................... 8-9
Developing Dynamic Web Applications with MySQL and PHP Comparison Functions ....................................................................................................................... 8-9 8.3.1 8.3.2 Control Flow Functions ....................................................................................................................8-10 8.3.3 Numeric Functions............................................................................................................................8-13 8.3.4 String Functions................................................................................................................................8-15 8.3.5 Temporal Functions ..........................................................................................................................8-16 8.3.6 NULL-Related Functions .................................................................................................................8-18 8.4 Chapter Summary .....................................................................................................................................8-23 9 SQL DML COMMANDS ..................................................................................................................................... 9-1 9.1 Learning Objectives................................................................................................................................... 9-1 9.2 The INSERT Statement ............................................................................................................................. 9-2 9.2.1 INSERT with SELECT...................................................................................................................... 9-3 9.2.2 INSERT with LAST_INSERT_ID .................................................................................................... 9-3 9.2.3 INSERT with NULL Values.............................................................................................................. 9-3 9.3 The UPDATE Statement ........................................................................................................................... 9-4 9.3.1 UPDATE with SET ........................................................................................................................... 9-5 9.3.2 UPDATE with ORDER BY .............................................................................................................. 9-5 9.3.3 UPDATE with LIMIT ....................................................................................................................... 9-5 9.4 The REPLACE Statement ......................................................................................................................... 9-6 9.4.1 INSERT with ON DUPLICATE KEY UPDATE Instead of REPLACE .......................................... 9-7 9.5 The DELETE Statement ............................................................................................................................ 9-8 9.6 Chapter Summary .....................................................................................................................................9-13 10 SQL JOINS ........................................................................................................................................................10-1 10.1 Learning Objectives..................................................................................................................................10-1 10.2 What is a Join?..........................................................................................................................................10-2 10.3 Inner Joins.................................................................................................................................................10-3 10.3.1 Comma Separated Inner Join ............................................................................................................10-3 10.3.2 The INNER JOIN Keywords..........................................................................................................10-4 10.4 Outer Joins................................................................................................................................................10-6 10.4.1 Left Outer Join..................................................................................................................................10-6 10.4.2 Right Outer Join................................................................................................................................10-8 10.5 Using Qualifiers and Aliases ....................................................................................................................10-9 10.5.1 Qualifying Column Names ...............................................................................................................10-9 10.5.2 Qualifying and Aliasing Table Names............................................................................................10-11 10.5.3 Self Joins.........................................................................................................................................10-12 10.6 Multi-Table UPDATE and DELETE Statements .....................................................................................10-13 10.7 Chapter Summary ...................................................................................................................................10-17 11 MYSQL DATA DRIVEN WEB BASED FORMS .....................................................................................................11-1 11.1 Learning Objectives..................................................................................................................................11-1 11.2 Connecting to MySQL..............................................................................................................................11-2 11.2.1 Independent Connection Information ...............................................................................................11-4 11.3 Retrieving Data.........................................................................................................................................11-6 11.4 The Web Interface ..................................................................................................................................11-10 11.5 Update Existing Data..............................................................................................................................11-16 11.6 Delete Data .............................................................................................................................................11-18 11.7 Inserting Data .........................................................................................................................................11-21 11.8 MySQL Metadata ...................................................................................................................................11-24 11.8.1 PHP Functions for Retrieving Metadata .........................................................................................11-27 11.9 MySQL Error Information......................................................................................................................11-29 11.10 Chapter Summary ...............................................................................................................................11-31 12 SESSION HANDLING...........................................................................................................................................12-1 12.1 Learning Objectives..................................................................................................................................12-1 12.2 What is Session Handling .........................................................................................................................12-2 12.3 Session Handling Tasks............................................................................................................................12-3 12.3.1 Encoding/Decoding Session Data.....................................................................................................12-5 12.4 PHP Session Handling with MySQL........................................................................................................12-6 12.4.1 MySQL Handling Logins Example ..................................................................................................12-6 12.4.2 Session Handling Configuration Options .......................................................................................12-10
Developing Dynamic Web Applications with MySQL and PHP 12.5 Chapter Summary ...................................................................................................................................12-13 13 OBJECT ORIENTED PROGRAMMING ...................................................................................................................13-1 13.1 Learning Objectives..................................................................................................................................13-1 13.2 Benefits of OOP........................................................................................................................................13-2 13.3 Working with Objects...............................................................................................................................13-3 13.4 Exception Handling ..................................................................................................................................13-6 13.5 Chapter Summary .....................................................................................................................................13-9 14 ESTABLISHING USER AUTHENTICATION ............................................................................................................14-1 14.1 Learning Objectives..................................................................................................................................14-1 14.2 HTTP Authentication................................................................................................................................14-2 14.3 PHP Authentication ..................................................................................................................................14-3 14.3.1 Hard-Coded Authentication ..............................................................................................................14-4 14.3.2 File-Based Authentication ................................................................................................................14-5 14.3.3 Database Authentication ...................................................................................................................14-7 14.4 Chapter Summary ...................................................................................................................................14-10 15 SECURING PHP AND MYSQL............................................................................................................................15-1 15.1 Learning Objectives..................................................................................................................................15-1 15.2 Building a Wall of Security ......................................................................................................................15-2 15.2.1 PHP Configurations ..........................................................................................................................15-3 15.3 Data Encryption ........................................................................................................................................15-5 15.4 Securing the MySQL Server (mysqld) .....................................................................................................15-6 15.5 MySQL Access Privilege System.............................................................................................................15-8 15.5.1 MySQL versus Operating System Accounts ....................................................................................15-8 15.5.2 Creating and Dropping User Accounts .............................................................................................15-9 15.5.3 Setting Account Password ................................................................................................................15-9 15.6 Privileges ................................................................................................................................................15-10 15.6.1 Types of Privileges That MySQL Supports....................................................................................15-10 15.6.2 The Grant Tables ............................................................................................................................15-12 15.6.3 Granting Privileges .........................................................................................................................15-14 15.6.4 The GRANT Statement ..................................................................................................................15-15 15.6.5 The SHOW GRANT Statement......................................................................................................15-16 15.6.6 Revoking Privileges........................................................................................................................15-18 15.6.7 Changing Account Passwords.........................................................................................................15-19 15.6.8 When Privilege Changes Take Effect .............................................................................................15-19 15.7 Chapter Summary ...................................................................................................................................15-21 16 CONCLUSION .....................................................................................................................................................16-1 16.1 Course Objectives.....................................................................................................................................16-1 16.2 Training and Certification Website..........................................................................................................16-2 16.3 Course Evaluation.....................................................................................................................................16-4 16.4 THANK YOU! ........................................................................................................................................16-5 16.5 Q&A Session ............................................................................................................................................16-6
Appendix A Appendix B Appendix C Appendix D Appendix E
Introduction to Linux........................................................................................................................A-1 Basic vi Commands ..........................................................................................................................B-1 Upload Form Example......................................................................................................................C-1 PHP Strings and Regular Expressions..............................................................................................D-1 Further Practice Solutions................................................................................................................. E-1
Developing Dynamic Web Applications with MySQL and PHP
4
Instructor Notes: This slide number corresponds to a slide with the course Table of Contents (Structure). There will be one of these slides before each chapter to show the current chapter being covered. This is to give the students a sense of the progress of the class.
CHAPTER 1 5
INTRODUCTION
Developing Dynamic Web Applications with MySQL and PHP
1 6
Chapter 1 – Introduction
INTRODUCTION
1.1
Learning Objectives This chapter introduces you to MySQL and MySQL AB, the support organization for MySQL. In this chapter, you will learn:
7
•
The details of the MySQL AB Business Model
•
What MySQL products and professional services are available from MySQL AB
•
Define and differentiate between Enterprise and Community
•
Which Operating Systems are currently supported
•
What is available through the MySQL Community web page
•
What is the MySQL Certification program
•
Which courses are available to you after this course
Instructor Notes: This slide number corresponds to a slide with information that is not included in the instructor or student guides. It is pertaining to getting to know the students in the class.
8
Instructor Notes: This slide number corresponds to a slide with information that is not included in the instructor or student guides. It is pertaining to the checklist of items to discuss before starting the class.
9
Instructor Notes: This slide number corresponds to a slide with information that is not included in the instructor or student guides. It is pertaining to explaining the format of the majority of the slides.
______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________
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1.2
Chapter 1 – Introduction
MySQL AB MySQL is a Relational Database Management System (RDBMS). MySQL AB develops and markets a family of high performance, affordable database servers and tools. Contributing to building the mission-critical, high-volume systems and products worldwide is what makes MySQL the world’s most popular open source database, as well as its reliability, excellent performance and ease of use. MySQL is not only the world’s most popular open source database, it’s also the fastest growing database in the industry, with more than 11 million active installations and 50,000 downloads per day.
MySQL is installed on every continent in the world (Yes, even Antarctica!)
The company was founded in Sweden by two Swedes and a Finn: David Axmark, Allan Larsson and Michael "Monty" Widenius who have worked together since the 80's. MySQL AB(Swedish for “Inc.”) is the sole owner of the MySQL server source code, the MySQL trademark and the mysql.com domain worldwide. MySQL has always been a strong supporter of the Open Source philosophy and the Open Source Community, and strives to work with partners that share the same values and mind-set. • The MySQL mission: To make superior database software available and affordable to all.
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Developing Dynamic Web Applications with MySQL and PHP
1.3 1.3.1 11
Chapter 1 – Introduction
MySQL Products MySQL Database Products MySQL provides database products to meet the needs of ISV/OEM, Enterprise, and Community Server users. MySQL database products are recognized for superior ease of use, performance, and reliability. • Enterprise Server o
The most reliable, secure and up-to-date version of the world's most popular open source database for cost-effectively delivering E-commerce, Online Transaction Processing (OLTP), and multi-terabyte Data Warehousing applications. (Available only with the MySQL Enterprise subscription).
• Community Server o
The MySQL database server for open source developers and technology enthusiasts who want to get started with MySQL. Supported by the large MySQL open source community. Under the General Public License (GPL), benefits to the open source community include a commercialgrade framework that is free of charge.
• Embedded Database o
The most popular choice for OEMs/ISVs who want to cost-effectively embed or bundle a reliable and high-performance relational database.
• Cluster o
A fault tolerant database clustering architecture for deploying highly available mission-critical database applications.
• MaxDB o
Formerly known as SAP DB, MaxDB is the result of a strategic alliance between MySQL and SAP to jointly develop and market an open source database for SAP/R3.
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Chapter 1 – Introduction
MySQL Enterprise A comprehensive set of enterprise-grade software, support and services directly from the developers of MySQL to ensure the highest levels of reliability, security and uptime. As a proactive service that helps you eliminate problems before they occur, it gives you everything you need in a single, unified offering to successfully develop and deploy business critical applications using MySQL. • Enterprise Server o The most reliable, secure and up-to-date version of the world's most popular open source database for cost-effectively delivering E-commerce, Online Transaction Processing (OLTP), and multi-terabyte Data Warehousing applications. • Network Monitoring and Advisory o Services to ensure the maximum quality, uptime, and performance of MySQL Enterprise systems. • Production Support o Around-the-clock support for the MySQL Enterprise server, along with consulting services and self-help knowledge aids.
13
• Network Enterprise Dashboard...
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Developing Dynamic Web Applications with MySQL and PHP 14
1.3.2
Chapter 1 – Introduction
MySQL GUI Tools A comprehensive set of open source visual database tools. These easy to use visual tools enable database developers and DBAs to be more productive. • MySQL Migration Toolkit o
Using a wizard-driven interface, the MySQL Migration Toolkit implements a proven methodology and walks you through the necessary steps to successfully complete a database migration project.
• MySQL Administrator o A powerful visual administration console that enables you to easily administer your MySQL environment and gain significantly better visibility into how your databases are operating. • MySQL Query Browser o An extremely user-friendly visual tool for creating, executing, and optimizing SQL queries for your MySQL Database Server. Bundled Tools The MySQL graphical user interface (GUI) tools discussed here come bundled together when downloaded from the MySQL website.
1.3.3 15
MySQL Drivers Standards-based drivers (also known as Connectors) enable developers to build database applications in their language of choice. In addition, a native C library allows developers to embed MySQL directly into their ‘C’ applications. MySQL provides the following drivers: • MySQL Connector/ODBC o Connect to a MySQL database server using the ODBC database API on all Microsoft Windows and most Unix platforms. • MySQL Connector/J o A native Java driver that converts JDBC (Java Database Connectivity) calls into the network protocol used by the MySQL database. • MySQL Connector/Net o An ADO.NET provider that allows access from the .NET platform using the network protocol used by the MySQL database. • MySQL Connector/MXJ o An MBean that allows seamlessly embedding the MySQL database server within the J2EE environment. • MySQL Connector/PHP (New to the MySQL family of Connectors) o For connecting to MYSQL from PHP on Windows (not necessary for Unix variants).
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1.4
MySQL Services
1.4.1
MySQL Training
Chapter 1 – Introduction
MySQL offers a comprehensive set of MySQL training courses that give you a competitive edge in building world-class database solutions. • Courses can be chosen individually, as part of a bundle, and/or following our suggested curriculum path for Developers and Database Administrators (DBAs). 1.4.2
MySQL Certification MySQL Certification Program is a high quality certification program that provides Developers and DBAs with the credentials to prove they have the knowledge, experience and skills to use and manage MySQL Server. • With MySQL personal certifications, you get to show that you are among the best-of-breed MySQL users and lay the foundation for becoming a trusted and valuable resource for your company and customers.
1.4.3
MySQL Consulting MySQL AB offers a full range of consulting services. Whether you are starting a new project, needing to optimize an existing MySQL application, or migrating from a proprietary database to MySQL, we have an affordable solution for you. • Using industry best practices and proven methodologies, your MySQL certified consultant will help you deliver on-time and on-budget.
1.4.4
MySQL Support MySQL offers a full range of support options. MySQL Technical Support is designed to save you time and to ensure you achieve the highest levels of performance, reliability, and uptime. • Community support o Mailing Lists o Forums (http://forums.mysql.com/) o Community Articles (http://dev.mysql.com/tech-resources/articles) o Bugs Database (http://bugs.mysql.com/) o No direct access to support engineers o PlanetMySQL Blogs (http://www.planetmysql.org/) o MySQL Reference Manuals (http://dev.mysql.com/doc) o MySQLForge (http://forge.mysql.com/) • Purchased support o Enterprise subscription o Support for MySQL Cluster o Support for MySQL Embedded (OEM/ISV) o MaxDB Support
o Online Knowledge Base ______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________
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Developing Dynamic Web Applications with MySQL and PHP 17
1.5
Chapter 1 – Introduction
Community vs. Enterprise There are many things to consider when choosing between using the Community server versus the Enterprise server subscription. The following charts summarize the uses and requirements for each and do a comparison to assist in understanding the differences. How does the MySQL Community work?
MySQL AB
Open Source Database Server Minimum Two Binaries/Year Fixes/Feature
MySQL Community
New Ideas
Code Contributions…
Constant Source Code Drops
Bug Reports…
Free Mgmt Tools/Connectors
Help, Forums…
Help, Forums…
Spread MySQL Goodwill…
The left side of this chart shows what MySQL provides to the user community. On the right, is what our user community provides back to us and to the whole community.
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Developing Dynamic Web Applications with MySQL and PHP 18
Chapter 1 – Introduction
How does the MySQL Enterprise work?
Community / Third Party Development
MySQL Community Server
Many Ideas / Submissions
Selected Submissions Become Features
Design/Development
Community Purpose
•
Community Recommendations
•
•
Community Server Code Contributions - Direct
•
Community Code Contributions – MySQL Forge
•
MySQL Enterprise Server
•
Delivery of Community and Customer Recommendations Acceptance/Rejection of Community Code Contributions
Mature Features Only
Enterprise Grade
•
Selected Feature Set for Enterprise Installations
•
Predictable Service Pack Schedule
•
Strong Internal Quality Assurance Testing
•
Community Testing and Validation
•
External Quality Assurance Testing
•
“As Needed” Release Schedule, including Bug Fixes and New Features
•
Certified for Popular Platforms and Applications
•
Formal Technical Support
Third party contributions
The above chart shows the progression of code feature implementation into the MySQL Enterprise Server; from user input, to MySQL Community Server placement/testing, to further improvements which are placed in the MySQL Enterprise Server product.
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Developing Dynamic Web Applications with MySQL and PHP 19
1.6
Chapter 1 – Introduction
MySQL Partners MySQL has had the privilege of forming alliances with excellent partners and attracting some of the most impressive customers in the industry! When you join our ranks, you are joining a winning team with a wide variety of MySQL implementations. It never ceases to amaze us, the innovative and powerful ways in which our tools are being used. To name only a few; Education • AUF (Agence Universitaire de la Francophonie) • University of California, Berkeley World Wide Web • Yahoo! • Wikipedia Finance • Chicago Mercantile Exchange • HypoVereinsbank Healthcare • Finnish National Public Health Institute • UNICEF Manufacturing • Yamaha • Epson
Technology • Apple • Motorola
Media • BBC • The Weather Channel (Weather.com)
Telecom • AT&T Wireless • Nokia
Open Source Projects • PHProjekt • eGroupWare
Transport • AXS Marine • Viasuisse
Retail • Axfood AB • Macy’s
Travel • Continental Airlines • Orbitz
"We have used MySQL far more than anyone expected. We went from experimental to mission-critical in a couple of months." Jeremy Zawodny--MySQL Database Expert Yahoo! Finance
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Developing Dynamic Web Applications with MySQL and PHP 20
1.7
Chapter 1 – Introduction
Supported Operating Systems MySQL runs on more than 20 platforms, giving users the kind of flexibility that puts them in control. Windows, Linux and Solaris are the most popular operating systems for running MySQL. Versions of MySQL are currently available for the following operating systems; • Windows (multiple)
• Mac OS/X
• SCO
• Linux (multiple)
• HP-UX
• Open BSD
• Solaris
• IBM AIX
• FreeBSD
• QNX
• SGI Irix • Novell NetWare
This list is continually being updated. For the most current information, please check our website: http://www.mysql.com . Source code and special builds are also available.
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Developing Dynamic Web Applications with MySQL and PHP 21
1.8
Chapter 1 – Introduction
MySQL Certification Program The MySQL Certification Program is a high quality certification program that provides developers and DBAs with the credentials to prove they have the knowledge, experience and skills to use and manage MySQL Server. MySQL will offer two tiers of certification for MySQL 5.0 (most recent version): 1. Certified MySQL 5.0 Developer (CMDEV) - proves mastery of the fundamental skills of using MySQL including creating and using databases and tables, inserting, modifying, deleting, and retrieving data. 2. Certified MySQL 5.0 Database Administrator (CMDBA) - proves mastery of the ability to manage MySQL Server including such advanced areas of database management, installation, security, disaster prevention and optimization. 3. Certified MySQL Cluster DBA (CMCDBA) - part of the DBA track which represents an advancement level exceeding CMDBA certification. In order to attain CMCDBA certification, you must attain CMDBA certification and pass one CMCDBA exam.
The chart above shows the curriculum path for Developers, Database Administrators and Cluster. They show the current course available for certification preparation, the respective exams, and the receipt of the certification. Certification Web Page For more information on the certification program and the content of the exams, see our Certification web page; http://www.mysql.com/certification/ . Exam Administration All exams are administered through one of more than 3,000 Pearson VUE testing centers available worldwide. And through the Linux Professional Institute proctor network. Visit the MySQL certification webpage, online forum or email
[email protected] for more information. ______________________________________________________________________________________________ Instructor Notes: Suggestion for extra exercise: go to www.vue.com/mysql and locate your nearest testing center. ______________________________________________________________________________________________ Information about all the exams can be found on the Certification web page. Have students find this page now, if ______________________________________________________________________________________________ the majority is interested. Also mention that the new Cluster certification is coming soon. ______________________________________________________________________________________________
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Developing Dynamic Web Applications with MySQL and PHP
1.9
Chapter 1 – Introduction
Training Curriculum Paths MySQL offers the most comprehensive set of MySQL training courses that enable the building of database solutions and competitiveness now and into the future. In addition to our open courses, we also offer inhouse training. The MySQL training services staff has put together great courses designed for success, and an excellent training path for each individual to reach his/her training goals. There are two tiers to the curriculum paths:
22
Developer Path • Introduction Courses o Developing Dynamic Web Applications with MySQL and PHP –This course will provide the tools needed for the development of dynamic web application. This course takes the student from the basics to the advanced features in four hands-on, heavy duty training days. Each student will have the opportunity to build a real-world application during the course. Prerequisites: Basic experience with designing HTML pages including HTML forms and experience with any programming language. Basic PHP skills. 4 days in length. o MySQL for Beginners – This course covers the fundamentals of SQL and relational databases, using MySQL as a teaching tool. Prerequisites: Basic computer literacy is required. Previous experience with any command-line program (such as MS-DOS or the MS Windows command prompt) is beneficial. 4 Days in length. • Intermediate Courses o MySQL for Developers - This instructor-led course is designed for students planning on developing applications that make use of MySQL 5.0 (and higher). This course covers essential SQL statements for data design, querying, and programming. In addition, it will prepare students for the MySQL Developer certification. Prerequisites: Some experience with Relational Databases and SQL. 5 days in length. o MySQL 5.0 Upgrading and New Features – This instructor-led course will provide in-depth knowledge needed to become proficient using MySQL 5.0. This training course will provide quality time both on the topic, hands-on labs and with the expert instructor. Prerequisites: Existing MySQL users who want to become proficient using MySQL 5.0. 3 Days in length. •
Advanced Courses o
•
Advanced Stored Procedures – This instructor-led course with focus on labs is designed to teach you how to maximize the use of stored procedures along with the knowledge to discern when an application should contain stored procedures and when they should not. 2 Days in length.
Virtual Courses o
MySQL Database Design - This instructor-led virtual course is designed for developers who wish to use sound database design principles while creating MySQL databases. This course will prepare each student with the skills needed to create databases that maintain data consistency, data integrity and data accuracy while improving SQL efficiency. Students will be provided with demonstrations that will support their ability to apply their learning immediately upon completion of the training. 4 hours in length.
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Developing Dynamic Web Applications with MySQL and PHP 23
Chapter 1 – Introduction
Database Administrator (DBA) Path • Introduction Courses o MySQL for Beginners – This course covers the fundamentals of SQL and relational databases, using MySQL as a teaching tool. Prerequisites: Basic computer literacy is required. Previous experience with any command-line program (such as MS-DOS) is beneficial. 4 Days in length. • Intermediate Courses o MySQL 5.0 Upgrading and New Features – This instructor-led course will provide in-depth knowledge needed to become proficient using MySQL 5.0. This training course will provide quality time both on the topic, hands-on labs and with the expert instructor. Prerequisites: Existing MySQL users who want to become proficient using MySQL 5.0. 3 Days in length. o MySQL for Database Administrators – This course covers essential DBA tasks such as, installation and upgrading, user management, disaster recovery, and optimization. In addition, it will prepare students for the MySQL Database Administrator certification. Prerequisites: Some experience with Relational Databases and SQL. 5 days in length. • Advanced Courses o MySQL Performance Tuning – The MySQL Performance Tuning course is designed for Database Administrators and others who wish to monitor and tune MySQL. This course will prepare each student with the skills needed to utilize tools for monitoring, evaluating and tuning. Students will evaluate the architecture, learn to use the tools, configure the database for performance, tune application and SQL code, tune the server, examine the storage engines, assess the application architecture, and learn general tuning concepts. 4 Days in Length. o MySQL Cluster - Learn how to install and configure the cluster nodes to ensure high availability. Also learn about all of the high availability features that are implemented in the new storage engine for the MySQL Cluster — fail-over between storage nodes, network partitioning protocol, two-phase commit and much more. Prerequisites: Attendance to the MySQL for Database Administrators or an equivalent mastery of database concepts, SQL and the MySQL server. 3 Days in length. Note: This is the sole course offering in the Cluster certification (CMCDBA) path. o MySQL High Availability - This course is designed for experienced database administrators and system architects that want to analyze and form a basis of understanding different high availability options, including clustering and replication solutions within MySQL. This course will provide the tools required to make the decision of what high availability solution is appropriate and how to implement a system with the correct design.. 3 days in length.
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Developing Dynamic Web Applications with MySQL and PHP 24
Chapter 1 – Introduction
1.10 MySQL Website Everything you ever wanted to know about MySQL and more can be found on our website: http://www.mysql.com. From the home page, you may navigate the web site with the tabs (pull-down menus) across the top, the menu along the left side, and/or the many links on the page.
______________________________________________________________________________________________ Instructor Notes: Do NOT open the website at this time. It will be done later in a lab. However, you may want to ______________________________________________________________________________________________ mention (and perhaps show) now about the MySQL website searching capability; www.mysql.com/ . ______________________________________________________________________________________________ ______________________________________________________________________________________________
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Developing Dynamic Web Applications with MySQL and PHP 25
1.10.1
Chapter 1 – Introduction
MySQL Community Web Page The MySQL Community web page is located at http://dev.mysql.com and is maintained by MySQL AB. This is the main support tool for the MySQL open source community and can provide valuable insight for Enterprise users also. Information such as the following can be found:
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Developing Dynamic Web Applications with MySQL and PHP 26
Chapter 1 – Introduction
• Product Downloads o MySQL Products are available under the "dual licensing" model. Under this model, users may choose to use MySQL products under the free software/open source GNU General Public License (commonly known as the "GPL") or under a commercial license. ISVs and Resellers, who are embedding and reselling MySQL as part of their own commercial solutions, can purchase a MySQL commercial license. • Documentation o The MySQL Reference Manual covers most of the areas of MySQL use. This manual is for both MySQL Community Edition and MySQL Network. If the answer(s) cannot be found from the manual, support can be purchased through MySQL Network, which provides comprehensive support and services. MySQL Network also provides a comprehensive knowledge base library that includes hundreds of technical articles resolving difficult problems on popular database topics such as performance, replication, and migration. • Articles o Check out the many articles available regarding specialized uses of MySQL, by the top experts from all over the globe. • MySQL Forums o Community and Enterprise Users alike can utilize the MySQL forums to interact with each other and the staff of MySQL AB. The forums are a great way to continue the community support for MySQL and keep both MySQL AB and the MySQL users in constant communication thus making MySQL even better. • Mailing Lists o MySQL provides its customers, both community and enterprise users, a way to keep up with the latest updates to MySQL software along with many other MySQL specific issues through the use of mailing lists. Mailing lists are similar to the forums but with the option to receive discussions and information about MySQL through a users local mail client. If a user cannot get an answer for their questions from one of our mailing lists, one option is to pay for support from MySQL AB, which puts the user in direct contact with MySQL developers. • MySQL Bugs o Bugs can be reported through the MySQL Bug page within MySQL, search for bugs submitted by MySQL users and MySQL AB staff and view bug statistics. • PlanetMySQL Blogs o Find the link to this site containing dozens of high quality articles every week from community and MySQL employees: http://www.planetmysql.org/ . • And much more!
______________________________________________________________________________________________ Instructor Notes: Demonstrate the use of the online MySQL Reference Manual. Make sure to stress the use of the ______________________________________________________________________________________________ reference manual throughout the class. If a user can’t get an answer for their questions from our website resources, ______________________________________________________________________________________________ one option is to pay for support from MySQL AB, which will puts the user in direct contact with MySQL developers (i.e. MySQL Enterprise). ______________________________________________________________________________________________
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Developing Dynamic Web Applications with MySQL and PHP
Chapter 1 – Introduction
Lab 1-A In this exercise you will review some web pages on the MySQL AB website. Make sure that your web browser window is displayed.
ACTION (You Do)
COMPUTER RESPONSE / Comments
1. Click in the text area of the Address/Location Toolbar.
The URL currently listed will be selected.
2. In the toolbar text area, type: www.mysql.com
The MySQL Homepage is displayed.
3. Click on the Products tab located at the top of the MySQL home page.
A list of currently available products will appear, with links for further information and downloads.
Scroll down the list to review the various product information provided. 4. Review the details of the new MySQL Enterprise program, by clicking on the Learn More >> link.
MySQL® Enterprise™ provides a comprehensive set of enterprise-grade software, support and services directly from the developers of MySQL to ensure the highest levels of reliability, security and uptime.
5. Click on the Services tab located at the top of the MySQL home page.
A list of currently available services will appear, with links for further information and downloads.
6. Review the details of the new MySQL Training program, by clicking on the Learn More >> link.
Featured information on this page will be updated periodically. For specific Training sub-topics select one of the links in the sub-menu in the upperleft corner of the page.
7. From the Training web page, select the Certification link in the sub-menu and review the contents.
Featured information on this page will be updated periodically. For specific Certification sub-topics select one of the links in the sub-menu in the upperleft corner of the page.
8. Click on the Services tab located at the top of the MySQL home page.
Returns to the top level Services page.
9. Review the details of MySQL Support programs, by clicking on the Learn More >> link.
Shows the various support programs available.
10. Click on the Community tab located at the top of the MySQL home page.
The community page contains many links to more information and access to various open communication forums.
11. Click on the News & Events tab located at the top of the MySQL home page.
Shows the latest MySQL happenings, from news stories to upcoming seminars.
______________________________________________________________________________________________ Instructor Notes: Do this lab “live” along with the students and emphasize that the primary goal of our website is to ______________________________________________________________________________________________ service their needs. Ask them if there are any particular topics they would like to find on the website (that are not ______________________________________________________________________________________________ included in the lab) and you may want to help them find a few items as part of the lab. ______________________________________________________________________________________________
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Developing Dynamic Web Applications with MySQL and PHP 27
Chapter 1 – Introduction
1.11 Chapter Summary This chapter introduced you to MySQL and MySQL AB, the support organization for MySQL. In this chapter, you learned: •
The details of the MySQL AB Business Model.
•
What MySQL products and professional services are available from MySQL AB.
•
Define and differentiate between Enterprise and Community
•
Which Operating Systems are currently supported.
•
What is available through the MySQL Community web page.
•
What is the MySQL Certification program.
•
Which courses are available to you after this course.
______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________
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Developing Dynamic Web Applications with MySQL and PHP
28
CHAPTER 2 29
LAMP
Developing Dynamic Web Applications with MySQL and PHP 30
2 2.1
Chapter 2 - LAMP
LAMP Learning Objectives This chapter provides the knowledge and methods used to verify the correct installations of MySQL and PHP on the web server being utilized. At the completion of this chapter, you will be able to: •
Explain the LAMP architecture
•
Verify that the Apache Server is installed and running
•
Verify that MySQL is installed and running
•
Verify that PHP is installed and accessible
______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________
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2.2
Chapter 2 - LAMP
LAMP Architecture The strength of the world wide web and the internet are that they stand upon open standards such as TCPIP, SMTP, UDP, HTTP and the like. This allows a Mac to talk to another systems mainframe and to send email to a windows computer. This open-ness may or may not extend to the tools used to deliver or create content on the world wide web. Proprietary tools such as Macromedia/Adobe FLASH, ADOBE, Cold Fusion, Microsoft IIS are tools developed by companies to generate revenue. An alternative paradigm exists. That is where individuals and companies collaborate in order to help each other to get various tasks done. This is called "open source". Open source software gives an end user the freedom to view and modify the source code. Typically they are free of cost but the main freedom is that the end user can view and modify the source code. This means that talented programmers who find ways to improve the source code can contribute. It means that companies that need a tool, say a webserver, can utilize Apache rather than paying for a commercial tool. In open source we all work together to get our jobs done. The value is in the access to quality tools without restrictions. In closed source products we pay someone else to solve our problems. They may or may not have our best interest in mind, or our needs and the needs for revenue may collide. The Open source tools are Linux, Apache, MySQL and PHP. In many ways they can be used as a replacement or alternative to IDE's such as J2EE, ASP.NET. • Linux - This is the operating system (O/S) of the LAMP architecture and serves as foundation for the rest of the applications used in the architecture. Linux, which refers to the Linux kernel that is a Unix-like operating system kernel, can be seen in many different "flavors" of operating system distributions that utilize the linux kernel to include Fedora, Ubuntu, Knoppix, OpenSUSE, etc. The majority of the distributions (along with the Linux kernel itself) is released under the GNU General Public License (GPL) and developed by contributors worldwide. • Apache - Apache refers to the Apache HTTP Server that is a web server that can be run on Unix-like systems (Linux for example), Microsoft Windows, Novell NetWare, Mac OS X and other operating systems. The Apache web server has played a major role in the success of the web by being a direct competitor to early proprietary web servers and opening the path for individuals and organizations to place their own "voice" on the web with little to no cost. The Apache Software Foundation, which is a non-profit corporation to support Apache software projects, develops and maintains the actual code (with a large number of open community of developers). The software itself is released under the Apache License which identifies the Apache HTTP Server as free software. • MySQL - MySQL refers to the multithreaded, multi-user SQL database management system which has more than 10 million installations worldwide. Supported by MySQL AB, a company which is dual headquartered in Uppsala, Sweden and Cupertino, California, USA maintains the mysql DBMS system and holds the copyright to most of the codebase. The MySQL DBMS acts as the database component that provides the back-end to a large number of the web applications in place today. MySQL has been a large player in such web applications as online stores, social networking sites, wiki's, etc. • PHP - PHP refers to the programming language that is used in the design of a large number of dynamic web pages. PHP is a reflective programming language, meaning the program code can be modified in the process of being executed based on its runtime behavior. This is ideal for the dynamic and interactive nature of the web. The rights to the PHP falls under a group called the "The PHP Group" and the ability to use the software is based on the PHP License, which according the Free Software Foundation is a license that identifies itself as being free software.
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Apache Server Being one of the components of the LAMP architecture, it is important to ensure that the Apache Server is installed and running on the Linux distribution being used. The easiest and least intrusive way of checking this is by opening a web browser on the local system and attempting to view the localhost web location. If there is a positive response when opening localhost from the web browser, then the Apache HTTP server is installed and running on the system. If the response is a web error, then the Apache HTTP is not running properly or not installed on the system. Downloading the Software The Apache Software Foundation is responsible for maintaining and supporting the Apache HTTP Server. Its website is http://www.apache.org which provides the details associated with the product lines that it offers and further information to install, configure and run the Apache HTTP Server on a wide range of operating systems. For the purpose of this course, the focus will be on installing and executing the Apache HTTP Server on the Linux distribution being used in the classroom environment. Installing the Software Once the files are downloaded to the operating system, it is time to extract the download file to an appropriate location for the server to execute from. In the linux environment, the choice used for the classrooms will be the /usr/local directory. This will be the location for all the software that will be installed in this class. Configuring the Install Script The next step is to configure the Apache HTTPd source tree for the Linux operating system and any additional specific requirements needed. The configuration of the install script is accomplished using the script configure included in the root directory of the distribution. There are multiple installation options that can be manipulated during the configuration. These configuration options are beyond the scope of this class. For class purposes, the default options will be chosen by running just the configure command without any options. Build the Package The next step is to build the various parts which form the Apache HTTPd package by simply running the make command. Due to the fact that the make command will build a base configuration it will take several minutes to compile. The actual time it takes to compile will vary widely depending on the hardware and the number of modules that have been enabled. Once the package has been made with the make command, it is now time to install the package using make install. Once this step is accomplished, a directory called apache2 will be created that will house the apache server files. Configuring The Apache server is configured by placing directives (which pass optional settings into the Apache server) in plain text configuration files. By default, the main configuration file that the Apache server will look for is called httpd.conf. This file is located in the apache2/conf directory by default. The majority of configuration options associated with this file are beyond the scope of this class and the default httpd.conf directives will be used.
Static vs. Dynamic Modules Apache can load static modules or they can be loaded dynamically. Dynamic is more common in the last few years. It takes less time to load a dynamic module. In order to see what modules are installed apache has an info and a status module. We will enable those modules and use them to make sure we have all the tools that we need. Mod status and Mod info display the output as a web page so we will need to make sure that the modules are loaded and that we have configured apache to deliver a "virtual URL " to display the content.
Instructor Notes: It may be more advantageous to show the websites where a person would download the files; ______________________________________________________________________________________________ however, the actual files should be downloaded by you (prior to the start of class) and made available locally to the students. This applies to all the files that will be downloaded for this chapter (Apache, MySQL, PHP). ______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________
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Starting and Testing the Server To start the Apache server, choose the apache2/bin directory. This directory contains the files associated with executing the components of the Apache server. The Apache server can be started by executing apachectl start from this directory. To test if the Apache server is working on the system, open a web browser on the local system and attempt to open http://localhost. If an error appears, the system is not configured properly and the steps should be repeated to determine the problem. If a web page appears, the server is running properly.
Lab 2-A In this exercise you will determine if the Apache HTTP Server is currently running on the local operating system. If the Apache HTTP Server is not installed, you will follow the steps required to download and install the latest version.
ACTION (You Do)
COMPUTER RESPONSE / Comments
1. In your web browser, attempt to open the localhost web page.
If http://localhost displays a web page, then the Apache server is installed on your system and no additional steps in this lab are required. However, if an error is returned, complete the remaining steps to install the Apache server on your system.
2. In your web browser's toolbar text area, type: httpd.apache.org/download.cgi
This will open the download page for the Apache HTTPd Server.
3. In the best available version section, choose the tar & zipped Unix Source link (httpd#.#.#.tar.gz) and save the file to the /tmp directory.
The downloaded file will take some time to download and patience should be expected.
4. In the /usr/local directory, type the following:
This will extract the file downloaded in step 3 into the /usr/local directory making a new subdirectory labeled httpd-#.#.#.
tar -xvf /tmp/httpd-#.#.#.tar.gz
Note: The instructor may have already downloaded this file and made it available in a local file system, check with the instructor before downloading.
replacing the #.#.# with the exact file identifier downloaded in step 3. 5. In the /usr/local/httpd-#.#.# directory, execute the following command: ./configure --prefix=/usr/local/ apache2 --enable-mods-shared= most 6. In the /usr/local/httpd-#.#.# directory, execute the following command:
This step configures the Apache HTTPd source tree for your specific operating system with the root directory for the Apache server being the apache2 subdirectory in the /usr/local directory. In addition, the enablemods-shared=most tells the apache install script to build most of the available loadable modules. This step builds the various parts which form the Apache HTTPd install package.
make 7. In the /usr/local/httpd-#.#.# directory, execute the following command:
This step will actually install the Apache server install package. Once this step is accomplished, a directory called apache2 should be created in the /usr/local make install directory that houses the apache server files. ______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________
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ACTION (You Do) 8. With the apache server files completed, there are a few configuration options that must be entered into the httpd.conf file before we are completed with the Apache step of the LAMP installation. However, a best practice is to make copies of existing configuration files prior to changing them. In the /usr/local/apache2/conf directory, create a copy of the httpd.conf file by entering the following command:
Chapter 2 - LAMP
COMPUTER RESPONSE / Comments The original httpd.conf is now copied to httpd.conf.bak giving us the ability to go pack and start over if need be (without having to remember all the changes that we made to the file). In addition, adding components and then testing them before going on to adding the next component is not a bad approach if your configuration files continue to cause you problems.
cp ./httpd.conf httpd.conf.bak 9. With the original configuration copied it is time to edit the httpd.conf file using your favorite editor. For this example the vi editor will be used: vi httpd.conf 10. First things that need to be addressed are the modules and their status (will they be loaded). The two modules that need to be loaded (among many) are mod_info and mod_status. You can search for the mod_info module by typing in vi the following:
vi stands for visual editor and is the default editor that comes with the Linux operating systems. This editor will allow us to make modifications to the httpd.conf file and complete the apache server setup. Note: Refer to Appendix B for a simple list of vi commands if you are unfamiliar with this program. If these lines are commented out (the start of the line contains a pound sign:#), please remove the comment. If you do not see this lines then add them. If you do not see mod_info.so or mod_status.so in your modules directory then contact your instructor
/mod_info.so You can locate the mod_status module in the httpd.config file by typing in vi the following: /mod_status.so 11. The next step is add the "Virtual URL's" for status and info to the httpd.conf file. Locate the end of the file and add the following lines: SetHandler server-info SetHandler server-status 12. Save your changes to the httpd.conf and exit the vi program.
The first section is responsible for allowing mod_info's output to be available. mod_info provides a detailed configuration and module information for your server (corresponding to modules, mostly) in display-order that are hyper-linked. The second section is responsible for allowing mod_status' output to be available. mod_status provides a representation of your web server's internal state and the comings and goings of its child processes. The changes are saved to the file.
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ACTION (You Do) 13. Test the configuration file for typos by typing the following in the /usr/local/apache2/bin directory:
Chapter 2 - LAMP
COMPUTER RESPONSE / Comments If the response is not "syntax OK" then return to the httpd.conf file and correct the error.
./apachectl configtest 14. Once the configuration test of the httpd.conf file responds with "syntax OK", it is now time to start the server by executing the following command: ./apachectl start
This will start the Apache HTTPd server on your system. Note: If an error is shown after executing this command that says "Could not reliably determine the server's fully qualified domain name ...", simply ignore this error for class purposes. This is stating that Apache does not know what server name to listen for.
15. Open the web browser on your system and attempt to browse to http://localhost/info and http://localhost/status which refers to the apache server running on your system.
If both of the web pages come up and provide information about the server, then apache was configured correctly and is executing properly. If an error appears, ask your instructor for assistance.
16. Stop the Apache server after ensuring that it is properly configured and running by typing the following command:
This will stop the Apache HTTPd server on the system. This step is important when installing the next two components of the LAMP architecture.
./apachectl stop
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MySQL Server Being another of the components of the LAMP architecture, it is important to ensure that the MySQL Server is installed and running on the Linux distribution being used. Downloading the Software MySQL AB is responsible for maintaining and supporting the MySQL Relation Database Server. Its website is http://www.mysql.com which provides the details associated with the product lines that it offers and further information to install, configure and run the MySQL Server on a wide range of operating systems. For the purpose of this course, the focus will be on installing and executing the MySQL 5.1 Server on the Linux distribution being used in the classroom environment. Installing the Software There are multiple methods for installing the MySQL Server on the operating system being used. For Linux, the easiest and least cumbersome is using a non-RPM distribution. These files can be located under the "Linux (non RPM packages) downloads" section. These files are called binary distributions that have already been compiled to work on the operating system that is selected. These files are tar files that have been compressed (tar.gz). Extracting the files is the extent of installing the actual MySQL binaries onto the operating system. Setting the MySQL user The MySQL server should not be run as root but instead should be run as another user whose sole purpose is to execute the MySQL server. This can be accomplished by creating a user called mysql that is assigned to a group called mysql. Once the user is created, all the data directory (/usr/local/mysql/data) should be assigned to this user and group. In addition, the mysql directory should at least be assigned to the mysql group (root can still own the directory). Initializing the MySQL databases There are a few databases that must be initialized prior to running MySQL for the first time. These databases include the mysql database which is used to control the security of all the databases on the server and test database which can be used for testing the server. There is a built in script to accomplish this step (/usr/local/mysql/scripts/mysql_install_db). Starting and Testing the Server With the MySQL binaries installed and the initial databases installed it is time to start the server. MySQL provides multiple ways to start the server, but the safest and most user friendly is using the mysqld_safe script located in the /usr/local/mysql/bin directory. This script should be run as the mysql user by executing the following conditions: /usr/local/mysql/bin/mysql_script -u mysql & After starting the MySQL server, the MySQL client (/usr/local/mysql/bin/mysql) can be run to interface with the server itself. Root Password?
After the MySQL server is started for the first time, it is important to set a root password. MySQL, by default, does not have a password assigned to the root password that is given complete access to all the databases; including the mysql database that controls all the authentication for the databases. To set the root password initially, execute the following command: /usr/local/mysql/bin/mysqladmin -u root password new_password
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Lab 2-B In this exercise you will determine if the MySQL Server is currently running on the local operating system. If the MySQL Server is not installed, you will follow the steps required to download and install the latest version.
ACTION (You Do) 1. To determine if MySQL is installed on your system, enter the following command in the O/S terminal window: whereis mysql
COMPUTER RESPONSE / Comments A directory will be shown where MySQL is installed (similar to the one listed below) if the system has MySQL installed. mysql: /usr/local/mysql If MySQL is installed already, you can either skip the remaining steps or contact your instructor to provide assistance in removing MySQL from your system so you can have practice in installing MySQL.
2. In your web browser's toolbar text area, type: dev.mysql.com/downloads
This will open the download page for the MySQL Server. Note: Ensure that the downloads panel in the left corner of the page has the 5.1 version of the server selected. If not, click on the 5.1 link under the Downloads section.
3. Choose the Download >> link under the "I Can Do It MySelf" column.
This is the link for the Community Server which will be used for class purposes. The Enterprise Server is the server that is recommended for production use systems, but in the case of this class, we will use the Community Server addition.
4. Choose the Linux (non RPM Packages) link from the list of available operating system downloads.
This link will place you in the Linux (non RPM Packages) section where you will be able to download the MySQL binary distribution.
5. Choose the download link to the left of the proper operating system that your system is running.
This step will perform the actual download of the MySQL installation files (mysql5.1.#.*.tar.gz).
6. In the /usr/local directory, type the following:
This will extract the file downloaded in step 5 into the /usr/local directory making a new subdirectory labeled mysql-5.1.#.*.
tar -xvf /tmp/ mysql-5.1.#.*.tar.gz replacing the /tmp/mysql5.1.#.*.tar.gz with the exact file identifier downloaded in step 5 along with the exact location of the download.
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ACTION (You Do) 7. Create a symbolic link directory to the newly mysql directory just created that will be easier to work with:
Chapter 2 - LAMP
COMPUTER RESPONSE / Comments This will create a directory called mysql which will be easier to work with when dealing with the MySQL server.
ln -s mysql-5.1.#.* mysql replacing the mysql-5.1.#.* with the exact file directory name created in step 6. 8. With MySQL installed (accessed though the mysql directory just created), it is time to prepare for running MySQL. The first thing that needs to be done is creating a group that MySQL will run under by typing the following:
To ensure security with MySQL, it is important to not run the server as root. This step creates a group called mysql that will only be used for running the MySQL server.
/usr/sbin/groupadd mysql 9. With the mysql group created, it is now time to create a mysql user assigned to this group by typing the following command:
This user, mysql, will be the user that the MySQL server will run under.
/usr/sbin/useradd -g mysql mysql 10. MySQL initially has no databases installed. This can be corrected by typing the following command in /usr/local/mysql directory:
This script will not only install the mysql and test database, but will also provide additional information on running the MySQL server.
./scripts/mysql_install_db 11. Now it is time to change the ownership of MySQL directories to ensure a level of security when running MySQL. This is accomplished by typing the following commands:
These commands provide the ownership changes required to provide a level of security when running the MySQL server.
chown -R root:mysql /usr/local/mysql chown -R mysql:mysql /usr/local/mysql/data 12. The following file should be edited to add the mysql library files to the program start-up: cd /etc/ld.so.conf.d echo /usr/local/mysql/lib > mysql.conf
On most Linux systems, the list of directories automatically searched during program start-up is stored in the file /etc/ld.so.conf. By adding MySQL to this configuration file you assure that its library files are easily accessible.
13. With all the steps completed, it is time to actually start the MySQL server. Type the following command to start the MySQL server:
The operating system will display the following information (or something similar) if the server is started:
cd /usr/local/mysql
Starting mysqld daemon with databases from /usr/local/mysql/data
./bin/mysqld_safe -u mysql &
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ACTION (You Do) 14. Another big issue that is important for security is the root password. By default, there is no root password. This can be corrected by issuing the following command (with training being the new password):
Chapter 2 - LAMP
COMPUTER RESPONSE / Comments This is a step that is missed by many administrators that install MySQL. By changing the password immediately upon installation, this potential security hole is closed.
/usr/local/mysql/bin/mysqadmin -u root password training 15. To ensure that MySQL is running as expected, type the following command to login to the MySQL client: /usr/local/mysql/bin/mysql -uroot -p
The MySQL client is a tool that allows us to interact with the MySQL databases directly. The actual command that was issued basically said that we are logging in as root (-uroot) and want to be prompted for the password (-p).
16. At the Enter password: prompt, type in the password that was assigned to the user root in step 14, training.
The following lines (or something similar) will be displayed if you were able to login correctly to the MySQL client: Welcome to mysql monitor. Commands end with ; or \g Your MySQL connection id is 2 Server version: 5.1.# MySQL Community Server (GPL) Type 'help;' or '\h' for help. Type '\c' to clear the buffer. mysql>
17. To give you a taste of MySQL, enter the following command in the MySQL client window: SHOW DATABASES;
18. To quit the MySQL client window, type the following command in the MySQL client window:
The following will be displayed showing the databases that are initially installed: +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | test | +--------------------+ The MySQL client window will be closed and the operation system prompt will be displayed.
quit;
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PHP With PHP being the final component of the LAMP architecture to be setup, it is important to ensure that PHP is installed and running on the Linux distribution being used. The majority of this course will be based on PHP and setting up the service correctly at this point will minimize problems in the long run. Similar to the process of installing the Apache server, PHP should be compiled for the server that it will be running on. Downloading the Software The sole implementation of PHP is produced by "The PHP Group" and released under the PHP License. There are many locations in which the source code for PHP can be obtained; however, php.net provides the most current and up to date version. Just like the other components of the LAMP architecture that have been discussed in this course, PHP can be compiled to work on many different platforms. For the purpose of this course, the focus will be on installing and running PHP on Linux. Installing the Software Once the files are downloaded to the operating system, it is time to extract the download file to an appropriate location for the server to execute from. In the linux environment, the choice used for the classrooms will be the /usr/local directory. This will be the location for all the software that will be installed in this class. Configuring the Install Script The next step is to configure the PHP source tree for the Linux operating system and any additional specific requirements needed. The configuration of the install script is accomplished using the script configure included in the root directory of the distribution. There are multiple installation options that can be manipulated during the configuration. These configuration options are beyond the scope of this class. For class purposes, the default options will be chosen by running just the configure command with the basic options associated with the Apache2 server and MySQL. Build the Package The next step is to build the various parts which form the PHP package by simply running the make command. Due to the fact that the make command will build a base configuration it will take several minutes to compile. The actual time it takes to compile will vary widely depending on the hardware and the number of modules that have been enabled. Once the package has been made with the make command, it is now time to install the package using make install. Once this step is accomplished, a directory called php will be created that will house the PHP files. Configuring PHP PHP is configured through an initialization file (php.ini) which can contain multiple options to support the PHP implementation for your server. The most common options to be addressed in this file is the location of the document root for the Apache server and components to add additional layers of security to the implementation.
Instructor Notes: Once the PHP is installed, it is ready for use and does not require any additional start up options. ______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________
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Lab 2-C In this exercise you will determine if the PHP programming language is currently running on the local operating system. If the PHP programming language is not installed, you will follow the steps required to download and install the latest version.
ACTION (You Do) 1. To determine if PHP is installed on your system, enter the following command in the O/S terminal window: whereis php
COMPUTER RESPONSE / Comments A directory will be shown where PHP is installed (similar to the one listed below) if the system has PHP installed. php: /usr/local/php If PHP is installed already, you can either skip the remaining steps or contact your instructor to provide assistance in removing PHP from your system so you can have practice in installing PHP.
2. In the toolbar text area, type: http://www.php.net/downloads.php
This will open the official download page for the PHP programming application.
3. Under the Complete Source Code heading, choose the link for the latest PHP (tar.gz) file.
This link will open a list of mirror sites for the download of the required file.
4. Choose the best (usually in close physical proximity) link to download the file and save the file to the /tmp directory.
This step will perform the actual download of the MySQL installation files (php5.#.#.*.tar.gz).
5. In the /usr/local directory, type the following:
This will extract the file downloaded in step 5 into the /usr/local directory making a new subdirectory labeled mysql-5.1.#.*.
tar -xvf /tmp/ php-5.#.#.*.tar.gz replacing the /tmp/php-5.#.#.*.tar.gz with the exact file identifier downloaded in step 4 along with the exact location of the download. 6. In the newly created directory, issue the following command: ./configure --prefix=/usr/local/php --with-apxs2=/usr/local/apache2 /bin/apxs
This step configures the PHP source tree for your specific operating system with the root directory for PHP being the php subdirectory in the /usr/local directory. In addition, the --with-apxs2 and --with-mysql tells the configurations script where the other components of LAMP are located.
--with-mysql=/usr/local /mysql --withmysqli=/usr/local/mysql/bin/mysql _config
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ACTION (You Do) 7. When the configuration script finishes, execute the following command:
Chapter 2 - LAMP
COMPUTER RESPONSE / Comments This step builds the various parts which form the PHP install package.
make 8. When the make script finishes, execute the following command: make install 9. In the /usr/local/php-5.#.#, execute the following command to create the default preconfigured initial setup: cp php.ini-recommended /usr/local/php/lib/php.ini 10. In the php.ini file just created, edit the file (using a program such as vi) to change the doc_root setting:
This step will actually install the PHP package. Once this step is accomplished, a directory called php should be created in the /usr/local directory that houses the PHP files. There are multiple pre-configured settings for a PHP install that you can use as an initial setup. php.ini-recommended is the most secure and rightfully identified in the name as the recommended one. This location identifies the document root directory for the local Apache web server.
doc_root="/usr/local/apache2/htdocs" 11. Another configuration option that should be changed in the php.ini file created in step 9, is allowing file uploads using PHP by changing the following setting: file_uploads=On 12. Change the follow directives: error_handler = E_ALL | E_STRICT display_error = On
If there is no need to upload files, this should be set to Off. By turning Off the capability to upload files using PHP, you set PHP to safe mode and place an additional level of security on the server. In this training, we will use the file upload function and must have this set to On. The error_handler setting ths will provide the most warnings and notices. Code that run cleanly with this setting has a far greater likelihood being portable. The display_error should be set to “off” for a production server.
13. Save your changes to the php.ini file and exit the editing program you were using to make the changes.
The changes are saved to the file.
14. In the /usr/local/apache2/conf directory, edit the httpd.conf file. Using the tools of vi, locate the end of the DirectoryIndex section and modify the configuration line to read:
This will ensure that files named index.html.var and index.php will be identified as the default pages for your html directories along with the standard index.html.
DirectoryIndex index.html index.html.var index.php
Note: Anytime changes are made to the httpd.conf file, it is important to comment what changes took place to include the date, by whom, what was modified/added and why. These comments should be entered near the changes that were made.
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ACTION (You Do) 15. After making the changes in step 13, search for the AddType configuration options under the mime_module section of the configuration file. Locate the end of this section and add the following line:
Chapter 2 - LAMP
COMPUTER RESPONSE / Comments This setting will ensure that any time the apache server is asked to execute a file with a .php extension it will use the proper server components to manage those files.
AddType application/x-httpd-php .php 16. Save your changes to the httpd.conf and exit the vi program.
The changes are saved to the file. Any requests to execute PHP files on the apache server will now be completed.
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Chapter 2 - LAMP
Putting It All Together Now that all the components of the LAMP architecture are set up, it is time to test each of the components and verify that everything is working correctly. Restarting Apache Apache was shutdown during the installation of MySQL and PHP and should be started back up to provide the web services necessary to test the PHP installation. To start the Apache server again, choose the apache2/bin directory. This directory contains the files associated with executing the components of the Apache server. The Apache server can be started by executing apachectl start from this directory. Testing PHP With the Apache server back up an running, it is time to test the installation of PHP on the server. This is accomplished by creating a test PHP file in the /usr/local/apache2/htdocs directory. This file (which is usually called test.php) will contain a PHP command () that will display all the configuration information associated with the local PHP installation. Automatic Starts of Apache and MySQL Up to this point, Apache and MySQL were manually being started and would need to continue to be manually started every time the operating system was restarted. This is not the most effective approach for many reasons, least of them being they are easy to forget at start up time when needing to be started manually. Linux (along with practically every other operating system) has the capability to start applications when the operating system is loaded (during planned or unexpected restarts). In Linux, this is accomplished by placing a copy of the start up executable files into the /etc/init.d directory. In addition, some additional steps such as making the new files executable and executing a Linux tool (update-rc.d) to ensure that all the proper links on the operating system are made to ensure each component is started when the operating system starts up. Updating the Exectuable Paths
We now have apache and all the associated executables in our /usr/local/apache2/bin directory. Our life would be easier if we could type apachectl instead of the full path over and over again. In addition, the same is true for running the mysql client. In order to do that we edit an environment variable called path. A number of files are read when we log in. One of them is /etc/profile but that requires that we login to activate. /etc/bash.bashrc is a good place, each new console that is launched reads /etc/bash.bashrc and thus adding the following lines to our /etc/bash.bashrc file will prevent us from needing to provide the full path everytime we want to execute a command from these directories: PATH=${PATH}:/usr/local/apache2/bin:/usr/local/mysql/bin Once that file is updated and saved, any new terminal windows (consoles) that start-up will have those in the path allowing mysql and/or apachectl to called without the paths preceding them.
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Lab 2-D In this exercise you will complete the final steps of setting up the LAMP architecture along with testing the setup. In addition, you will configure the operating system to start up MySQL and Apache automatically when it starts up.
ACTION (You Do) 1. In the /etc/ directory, edit the following file: vi bash.bashrc
2. Locate the end of the file and add the following and then save and close the file: PATH=${PATH}:/usr/local/apache/bin: /usr/local/mysql/bin
COMPUTER RESPONSE / Comments There are a couple of files that modify your PATH. They all work but some are read all the time for everyone, some are read for each user. /etc/bash.bashrc only works for bash but it is automatic when a console is launched, no global logout required (unlike the profile files). The path for the apache server and the MySQL server binary directories is added to the path preventing us from needing to precede each command with the full path.
3. To be able to use the "path-less" approach to executing apache and mysql commands, shut down the current terminal window and open a new one.
This will give you access to using the "path-less" approach.
4. Execute the following command (from any directory due to our PATH having the binary directory of Apache):
This will restart the Apache server.
apachectl start 5. In the document root directory of Apache, located at /usr/local/apache2/htdocs, create a new file called test.php containing the following line of code:
This file will display all the configuration options of PHP when called from the http://localhost directory in the web browser.
Close and save the file. 6. In your web browser, call up the following URL: http://localhost/test.php 7. In the operating system terminal window, copy the mysql.server file to the /etc/init.d directory to ensure that MySQL will start when the operating system starts:
This will display multiple configuration options showing that PHP, Apache and MySQL are working. This step will copy the MySQL startup file to the /etc/init.d which is a directory containing initialization and termination scripts for changing init states.
cp /usr/local/mysql/ support-files/mysql.server /etc/init.d/mysql
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ACTION (You Do) 8. Add the ability for the new file in the /etc/init.d directory to be executed: chmod +x /etc/init.d/mysql 9. To complete the process of MySQL being started when the operating system is started, execute the following command:
Chapter 2 - LAMP
COMPUTER RESPONSE / Comments This will give the new file created, /etc/init.d/mysql to be executable thus allowing it to execute when the operating system starts up. update-rc.d is a utility (on Debian operating systems) that creates all the appropriate links to ensure that a file is executed on start up.
chkconfig –-add mysql 10. For Apache, the process of ensuring that the web server starts up on the operating system start up is similar to MySQL. The first step is to make a copy of the apachectl executable in the /etc/init.d directory:
This step will copy the Apache startup file to the /etc/init.d which is the same directory where the MySQL startup script was placed.
chkconfig –-add httpd 11. Add the ability for the new file in the /etc/init.d directory to be executed: chmod +x /etc/init.d/httpd 12. To complete the process of MySQL being started when the operating system is started, execute the following command:
This will make the new file created ( /etc/init.d/httpd) to be executable thus allowing it to execute when the operation system starts up. update-rc.d will create all the appropriate links to ensure that httpd is executed on start up.
update-rc.d httpd defaults 13. At this point, you can shut down your operating system and restart it to check to see if the LAMP architecture starts up as expected.
Once you have restarted your operating system, complete step 3 to test if everything is working.
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Chapter 2 - LAMP
Chapter Summary In this chapter, you have learned to: •
Explain the LAMP architecture
•
Verify that the Apache Server is installed and running
•
Verify that MySQL is installed and running
•
Verify that PHP is installed and running
The acronym LAMP stands for a group of independent open-source software and tools that when used together allow for the execution, development and deployment of dynamic websites and servers. The tools used reflect the acronym name: Linux, Apache, MySQL and PHP. Being one of the components of the LAMP architecture, it is important to ensure that the Apache Server is installed and running on the Linux distribution being used. MySQL AB is responsible for maintaining and supporting the MySQL Relation Database Server. Its website is http://www.mysql.com which provides the details associated with the product lines that it offers and further information to install, configure and run the MySQL Server on a wide range of operating systems. The sole implementation of PHP is produced by "The PHP Group" and released under the PHP License.
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CHAPTER 3 38
PHP FOUNDATIONS
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Chapter 3 - PHP Foundations
PHP FOUNDATIONS Learning Objectives This chapter provides the foundations knowledge necessary to utilize the basic components of PHP to build more complex web applications. At the completion of this chapter, you will exhibit strong knowledge of PHP foundations by being able to: •
Delimit PHP code within HTML
•
Comment PHP code
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Construct Feedback to users through tool interfaces and requested responses
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Utilize the Data Types available in PHP
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Utilize Key Control Statements
•
Develop Reusable Code with user defined functions
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Chapter 3 - PHP Foundations
Delimiting PHP Code PHP was originally designed to be used in conjunction with a web server, and in the case of the LAMP architecture, the Apache Web Server. PHP applications are designed embedding PHP scripts within a web page along with its HTML. Unlike standard HTML pages which are sent directly from the web server to the end user, PHP files are first interpreted by the PHP application which then converts the PHP script into another form for display. This process eliminates the end user from being able to see the original PHP script that was embedded in the HTML and provides true interaction in HTML files. This process is similar to proprietary applications such as ASP and Coldfusion; however, PHP is Open Source and crossplatform. PHP Tags PHP scripts are distinguished from the HTML scripts by using delimiting characters that tell the server to execute the PHP application to interpret that which is contained in the code. There are four ways to accomplish this; however, the first two listed below are the safest for portability and conflict prevention: • Default Syntax - The default syntax is starting the PHP script with . The following example demonstrates how this would look within HTML code: PHP Default Syntax PHP Default Syntax • Script Syntax - Due to limitations with certain HTML editors, PHP added the ability to support a mainstream delimiter variant, . The following example demonstrates how this would look: print "This is an example of using PHP script delimiting syntax"; • Short Tags - Due to the fact that many programmers are interested in minimizing the amount of code that needs to be written to accomplish a task, PHP implemented a shorter delimiter syntax to support this desire. Instead of needing to type • ASP-Style - There are many PHP programmers that have experience with other similar programming languages, such as ASP. ASP delimits code using . PHP has provided support for this type of delimiting. The following example demonstrates how this would look:
Instructor Notes: Short-Tag delimiters may be convenient, but they can clash with XML and XHTML. The Default Syntax is the type of delimiting that will be used throughout this course and the one that should be recommended. Short tags are also discouraged by the PHP community, PHP developers and Zend. ______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________ ______________________________________________________________________________________________
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Chapter 3 - PHP Foundations
Comments When it comes to commenting code, the consensus is it is necessary but the reality is it rarely is done. It has been said that commenting code is like cleaning the bathroom - no one ever wants to do it but a clean bathroom creates a more pleasant experience for all that will need to use it. There are many types of commenting strategies with each having advantages and disadvantages over each other. The key is to comment, how that is accomplished is best worked within a team environment and calls for a great deal of flexibility. The following are types of typical commenting that should be considered along with how they would be implemented inside of PHP code: Code Commenting This form of commenting is not considered traditional commenting (in the sense of creating remarks to support the code) but is closer related to good programming design principles. This best practice approach to coding involves using coding names that describe the action that is taking place. $MarriageDate = "July 14, 1970"; function deleteOrder (orderID, actionDate); These examples show that the variable or function name give a description of what is being performed. Before abbreviating any code identifiers, make sure that they are descriptive enough so that others who would need to read the code would understand their meaning upon first glance. Any time that needs to be devoted to deciphering a given naming convention is clearly a waste of time and should be considered over any advantage of minimizing the extra key strokes required by the initial programmers. InLine Commenting The most basic form of commenting is that which is referred to as inline or single line commenting. This type of commenting has its history in C++ and has become the standard approach to commenting for many programmers (when they comment). PHP supports this type of commenting by using two consecutive forward slashes (//) preceding any comments added. $MarriageDate = "July 14, 1970"; // Official Marriage Date // This function will provide the code required to delete an order
function deleteOrder (orderID, actionDate); With inline comments, there is no need to delimit the comments conclusion, the carriage return (\n) performs that action. Shell Syntax InLine commenting can also be accomplished by using the pound sign (#) versus the two consecutive forward slashes (//) preceding any comments added. Both are acceptable and work interchangeably; however, for consistency one style should be chosen over the other. Switching back and forth between the two styles is acceptable but is not a best practice when others are reading your code.
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Muliple-Line Commenting It is possible to use inline commenting to create a more verbose and descriptive comment; however, there is an alternative when a comment requires the use of multiple lines. By preceding comments with a forward slash followed by an asterisk (/*) and then closing out the comments with an asterisk followed by a forward slash (*/) multiple lines of comments can be added to the code. /* Script General Information File Name: default.php Creator: Joe Smith, +1(313) 443-4433,
[email protected] Date Created: 2007/04/11 Purpose: The default script for all scripts created by Joe Smith Last Update: 2007/05/01 */ As shown here, this type of commenting is extremely useful where the comments do not directly correlate with any component of the code, but the code in general. HTML Comment Tag The commenting types up to this point addressed the commenting capabilities in PHP code; however, due to the fact that PHP code is embedded in HTML code it is useful to understand HTML's commenting capabilities. In HTML, commenting is available by creating a comment tag which consists of a less than character followed by an exclamation point and two dashes (). This type of commenting can be useful; however, unlike PHP commenting, that will not be visible to the end user when the web page is displayed, HTML commenting can be seen in the source of the web page.
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Chapter 3 - PHP Foundations
Construct Feedback The strength of the web has been the ability for practically anyone to provide information (accurate or not) to anyone who is interested in viewing the web pages that contain that information. With HTML, the static nature of the information being displayed limits the amount of true customization that can be provided; however, PHP provides truly dynamic content by creating custom content each time the web page is displayed. To accomplish this display of information, PHP has four functions that make this happen: • print() - This statement is designed to provide user feedback; in other words, this function "prints" content to the HTML code which in turn will be displayed on the web page when called. The print() function can display both raw strings and variables. As shown above, there are multiple ways to use the print function. In addition, breaking the function components across multiple lines is acceptable. The function will continue to read the components until it reaches the semi-colon delimiter (;) which tells the function to complete the process. • echo - The echo function is similar to the print function in that it can "print" content to the HTML code; however, it can not be used in more complex expressions because it returns a void versus the print function which will return a boolean value. Except for this difference, the echo function is no different than the print function. With that thought in mind, many programmers choose to just use the print function to prevent this limitation as they advance in their programming skills.
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Chapter 3 - PHP Foundations
• printf() - The printf function performs the same function as the print command with the exception that there is greater control over the formatting of the "printed" text. The printf function works from the standard print approach for "printing" text to HTML: Of course, the above demonstration does not add any value to the standard print function. But the printf function does not stop there, the following demonstrations show how the format argument can be included to provide a level of formatting to the strings referenced in the printf function: A complete list of supported type specifiers is located in Appendix D. In the case of the third printf function listed above, the location of the string argument can be chosen by placing the location (#$) with the format type. In the case of %3\$s, the third argument was selected and formatted as a string. The reason for the escape character (\) preceding the dollar sign ($) is to ensure that it was considered part of the formatting versus an actual dollar sign as used in the first printf function. • sprintf() - The sprintf function performs the same functions as the printf function except it stores the result of the function into a variable.
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Chapter 3 - PHP Foundations
PHP Data Types A data type identifies the characteristics that the assigned data will be interpreted by when interacting with the PHP programming language. When a value is assigned a specific data type, the PHP interpreter will work with the data based on the expected type of data it is. For example, 27654 could be considered a numeric data type or it could be considered a string data type, such as in the zip code for a customer. Even though you could perform mathematical equations on the zip code, it would make no sense to do so. Thus, zip codes, even though they look like they would be numeric numbers should be identified as a string data type to eliminate problems such as zip codes that start with zero (ex. 08102). Assigning the correct data type to the expected value is an important part of working with PHP. There are three categories of data types in PHP: Scalar, Compound and Special.
44
3.5.1
Scalar Data Types A scalar data type is identified as being able to hold one value at a time. In PHP, there are four data types that fall into this category.
Australia $Country
22 $Temperature
• Boolean - A boolean value is a truth value, either 'true' or 'false', often coded 1 and 0, respectively. When a value is assigned the Boolean data type, there are only two responses that the value can be assigned: True (1) or False (0). If a value is assigned anything other than these two values, it will default to True (1). • Integer - An integer is a whole numeric data type (meaning it does not contain any fractions) that can be set to decimal (base 10), octal (base 8) or hexadecimal (base 16). The following demonstrate some of the values that can be assigned the numeric data type: The maximum number that can be assigned to an integer is based on the system. 32 bit systems have a maximum signed integer range of -2147483648 to 2147483647. The maximum signed integer value for 64 bit systems is 9223372036854775807. Any value that exceeds the maximum integer size will be assigned the float data type.
Instructor Notes: For integers, if running a 32bit OS on a 64bit CPU, the max integer value will still be 2147483647. It really has more to do with the compilers, math libraries and OS limitations as well as those of ______________________________________________________________________________________________ the cpu type. Note to consider when discussing data types as it will relate to MySQL: PHP always interprets anything returned from mysql as strings. This means that any result returned from mySQL is not truncated nor ______________________________________________________________________________________________ converted because PHP interprets it a string not an integer. ______________________________________________________________________________________________ ______________________________________________________________________________________________
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• Float - Floating point numbers are any number that has a fractional component or exceed the integer maximum values. This data type is also referred to as floats, doubles or real numbers. Floats are used to represent such numbers as monetary values, distances, weights, scientific notations and a host of other values: The size of a floating point number is dependent by the system being used. In addition, floating point numbers are not as accurate as integer numbers when it comes to precision. Even simple numbers like 0.2 and 0.17 can not be converted into their binary equivalents without a loss of precision. With that said, floating point numbers should never be used in comparison operations without building in logic such as rounding numbers prior to the comparison operation or using a tolerance value that would be an acceptable difference between the compared values for comparison operations. • String - A string data type is a series of characters that are associated with each other in a defined order. There is no limit to the length of a string data value. The following represent some of the values that can be assigned to a string data type: The characters that can be used in PHP string data types are limited to the ISO 8859-1 or Latin-1 character set. This character set allows for 256 (the size of a byte) different possible characters (191 of them that are actually printable); however, there is support in PHP to encode strings to the UTF-8 standard (UTF-8 is a standard mechanism used by Unicode for encoding wide character values into a byte stream).
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Chapter 3 - PHP Foundations
Compound Data Types A compound data type allows for multiple values to be associated with a single entity. The primary purpose of a compound data type is to act as containers for other kinds of data. In PHP, there are two types of data types that fall under into this category. France 3 • Arrays - These are a series of like values Germany 13 $Position 2 c that are assigned to an individual variable Russia 10 $Country 1 $Position b with each individual value in the array being Australia 22 $Country $Position a 0 referenced with a unique identifier. Once $Country $Temperature these values are stored into an array, it is possible to retrieve individual values or to perform multiple actions against the stored values. The following demonstrates the storing and retrieval of an array set:
