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Notes --with-mysql[=DIR] include MySQL support. DIR is the MySQL base directory. If unspecified,
the bundled MySQL library will be used. --with-oci8 [=DIR] include Oracle-oci8 support. Default
DIR is ORACLE_HOME. --with-ibm-db2[=DIR] include IBM DB2 support. DIR is the DB2 base
install directory, defaults to /home/db2inst1/sqllib --with-pgsql[=DIR] Include PostgreSQL
support. DIR is the PostgreSQL base install directory, defaults to /usr/local/pgsql.
You cannot build PHP with support for a database whose client libraries you do not have on
your system. For example, if you do not have the Oracle client libraries, you cannot build PHP
with support for Oracle databases. Use the phpinfo( ) function to check for database support
in your installation of PHP.
The MySQL database is very often used with PHP.
10.1.1 Create a Connection to a MySQL Database
Before you can access data in a database, you must create a connection to the database.
In PHP, this is done with the mysql_connect() function.
Syntax
mysql_connect(servername,username,password);
Parameter Description

servername Optional. Specifies the server to connect to. Default value is
“localhost:3306”

username Optional. Specifies the username to log in with. Default value is the
name of the user that owns the server process
password Optional. Specifies the password to log in with. Default value is “”

Note: There are more available parameters, but the ones listed above are the most important.

In the following example we store the connection in a variable ($con) for later use in the script.
The “die” part will be executed if the connection fails:

<?php
$con = mysql_connect(“localhost”,”peter”,”abc123”);
if (!$con)
{
die(‘Could not connect: ‘ . mysql_error());
}

// some code
?>

10.1.2 Closing a Connection
The connection will be closed automatically when the script ends. To close the connection before,
use the mysql_close() function:

<?php
$con = mysql_connect(“localhost”,”peter”,”abc123”);

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