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Introduction - Connect

Introduction - Connect -- Connecting and disconnecting a database

Description

To connect to a database you have to use the function connect(), which requires a valid DSN as the first parameter. This parameter can either be a string or an array. If using an array, the array used gets merged with the default information: 
$dsn = array(
    'phptype'  => false,
    'dbsyntax' => false,
    'username' => false,
    'password' => false,
    'protocol' => false,
    'hostspec' => false,
    'port'     => false,
    'socket'   => false,
    'database' => false,
);
Any elements you set override the defaults and the remainder stay at their defaults.

The second parameter is the optional $options array that can contain runtime configuration settings for this package. See setOption() for more information on the available settings.

In case of success you get a new instance of the database class. It is strongly recommened to check this return value with isError().

To disconnect use the method disconnect() from your database class instance.

Example 26-1. Connect and disconnect

<?php
require_once 'DB.php';

$dsn = 'pgsql://someuser:apasswd@localhost/thedb';
$options = array(
    'debug'       => 2,
    'portability' => DB_PORTABILITY_ALL,
);

$db =& DB::connect($dsn, $options);
if (DB::isError($db)) {
    die($db->getMessage());
}

// ...

$db->disconnect();
?>

Example 26-2. Connect using an array for the DSN information

<?php
require_once 'DB.php';

$dsn = array(
    'phptype'  => 'pgsql',
    'username' => 'someuser',
    'password' => 'apasswd',
    'hostspec' => 'localhost',
    'database' => 'thedb',
);

$options = array(
    'debug'       => 2,
    'portability' => DB_PORTABILITY_ALL,
);

$db =& DB::connect($dsn, $options);
if (DB::isError($db)) {
    die($db->getMessage());
}
?>

When connecting to SQLite using a DSN array, the value of the mode element must be a string: 
<?php
$dsn = array(
    'phptype'  => 'sqlite',
    'database' => 'thedb',
    'mode'     => '0644',
);
?>

Example 26-3. Connect to MySQLi via SSL using an array for the DSN information

The ssl element of the $options array must be set to TRUE in order for SSL to work. Each of the extra elements in the $dsn array (key through cipher in the example below) are optional. 

<?php
require_once 'DB.php';

$dsn = array(
    'phptype'  => 'mysqli',
    'username' => 'someuser',
    'password' => 'apasswd',
    'hostspec' => 'localhost',
    'database' => 'thedb',
    'key'      => 'client-key.pem',
    'cert'     => 'client-cert.pem',
    'ca'       => 'cacert.pem',
    'capath'   => '/path/to/ca/dir',
    'cipher'   => 'AES',
);

$options = array(
    'ssl' => true,
);

$db =& DB::connect($dsn, $options);
if (DB::isError($db)) {
    die($db->getMessage());
}
?>

See

DB_Error, setOption(), "Intro - Portability"

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