Creating Database Tables

After the database structure is designed and the database has been created, individual tables can be added. Using accurate assignment of data types and their associated options, tables can be added to the database.

The command syntax is shown below, including the various column and table options;

CREATE TABLE <table> ( <column name> <column type> [<column options>],[<column name> <column type> [<column options>],…,] [<index list>])[<table options> ];

Example:

mysql> CREATE TABLE CountryLanguage (
         -> CountryCode CHAR(3) NOT NULL,
         -> Language CHAR(30) NOT NULL,
         -> IsOfficial ENUM('True', 'False') NOT NULL DEFAULT 'False',
         -> Percentage FLOAT(3,1) NOT NULL,
         -> PRIMARY KEY(Country, Language)
         -> )ENGINE = MyISAM COMMENT='Lists Language Spoken';

A line-by-line description of the above CREATE TABLE statement:

1. The table being created will be given the name CountryLanguage - this is the beginning of a grouping of column definitions that ends on the line 7 beginning with ") ENGINE = ..."

2. CountryCode --column in the table with a datatype of Char (size of 3) that cannot have an unknown or NULL value, and the comma ( ,) means continue defining columns

3. Language--another column of a datatype CHAR and a length of 30 that also can not have an unknown or NULL value

4. IsOfficial --column name ENUM is a datatype with only the values of True or False ('True' , 'False') and NOT NULL means each row must be true or false no t (unknown) If the value is unknown it will list as false by the phrase DEFAULT 'False'

5. Percentage —column with a datatype of FLOAT and values assigned at 3 total digits with 1 digit to the right of the decimal, cannot have NULL values

6. PRIMARY KEY--defines the type of index and what columns it applies, in this case a combo of both Country and Language to define a uniq ue identifier of each row or each entity

7. ) is the closing of a group of definitions describing the column names and index, ENGINE defines the pluggable storage engine used to manage the data and retrieve the data. (MyISAM in this case), COMMENT is phrases used by the person defining the table to explain the table (the purpose is to list the languages used in each given country), the ; means execute this command and create the table CountryLanguage.

PHP INTRODUCTION

PHP (recursive acronym for PHP: Hypertext Preprocessor ) is a widely-used open source general-purpose scripting language that is especially suited for web development and can be embedded into HTML. PHP stands for P HP: H ypertext P reprocessor PHP is a server-side scripting language, like ASP PHP scripts are executed on the server PHP supports many databases (MySQL, Informix, Oracle, Sybase, Solid, PostgreSQL, Generic ODBC, etc.) PHP is an open source software PHP is free to download and use Why PHP? PHP runs on different platforms (Windows, Linux, Unix, etc.) PHP is compatible with almost all servers used today (Apache, IIS, etc.) PHP is FREE to download from the official PHP resource: www.php.net PHP is easy to learn and runs efficiently on the server side What can PHP do? Anything. PHP is mainly focused on server-side scripting, so you can...

Storage Engine Breakdown

The following diagram represents a simplified view of the MySQL server and its interaction with the storage engines. The following properties are storage engine dependant: • Storage Medium – Each table uses its own method of storing the data it contains. • Transactional Capabilities – Certain storage engines handle transactional processing which ensures that integrity of a database is maintained during the processing of multiple SQL statements.

SQL Joins

1. Login in to the mysql client using the login name and password provided by your instructor (if not already logged in). 2. View the existing databases that the MySQL Server is maintaining. SHOW DATABASES; 3. Utilize the photo_album database. USE photo_album; ---- If Need be, recreate the database and load the SQL data in that will be used for this lab CREATE DATABASE photo_album; SOURCE /tmp/photo_album.sql; 4. Query the database to display the active primary customer (email, first and last name) and all the associated active login names associated with that customer. SELECT customers.email_customer, customers.fname, customers.lname, logins.login_name FROM customers, logins WHERE customers.email_customer = logins.email_customer AND customers.active_customer = 'True' AND logins.active_login = 'True';

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