Object oriented style
Procedural style
$link
[, string $host
[, string $username
[, string $passwd
[, string $dbname
[, int $port
[, string $socket
[, int $flags
]]]]]]] )Establish a connection to a MySQL database engine.
This function differs from mysqli_connect():
-
mysqli_real_connect() needs a valid object which has to be created by function mysqli_init().
-
With the mysqli_options() function you can set various options for connection.
-
There is a
flags
parameter.
Procedural style only: A link identifier returned by mysqli_connect() or mysqli_init()
Can be either a host name or an IP address. Passing the NULL
value or the string "localhost" to this parameter, the local host is assumed. When possible, pipes will be used instead of the TCP/IP protocol.
The MySQL user name.
If provided or NULL
, the MySQL server will attempt to authenticate the user against those user records which have no password only. This allows one username to be used with different permissions (depending on if a password as provided or not).
If provided will specify the default database to be used when performing queries.
Specifies the port number to attempt to connect to the MySQL server.
Specifies the socket or named pipe that should be used.
Note:
Specifying the
socket
parameter will not explicitly determine the type of connection to be used when connecting to the MySQL server. How the connection is made to the MySQL database is determined by thehost
parameter.
With the parameter flags
you can set different connection options:
Name | Description |
---|---|
MYSQLI_CLIENT_COMPRESS | Use compression protocol |
MYSQLI_CLIENT_FOUND_ROWS | return number of matched rows, not the number of affected rows |
MYSQLI_CLIENT_IGNORE_SPACE | Allow spaces after function names. Makes all function names reserved words. |
MYSQLI_CLIENT_INTERACTIVE | Allow interactive_timeout seconds (instead of wait_timeout seconds) of inactivity before closing the connection |
MYSQLI_CLIENT_SSL | Use SSL (encryption) |
Note:
For security reasons the
MULTI_STATEMENT
flag is not supported in PHP. If you want to execute multiple queries use the mysqli_multi_query() function.
Returns TRUE
on success or FALSE
on failure.
MySQLnd always assumes the server default charset. This charset is sent during connection hand-shake/authentication, which mysqlnd will use.
Libmysqlclient uses the default charset set in the my.cnf or by an explicit call to mysqli_options() prior to calling mysqli_real_connect(), but after mysqli_init().
Object oriented style
<?php $mysqli = mysqli_init(); if (!$mysqli) { die('mysqli_init failed'); } if (!$mysqli->options(MYSQLI_INIT_COMMAND, 'SET AUTOCOMMIT = 0')) { die('Setting MYSQLI_INIT_COMMAND failed'); } if (!$mysqli->options(MYSQLI_OPT_CONNECT_TIMEOUT, 5)) { die('Setting MYSQLI_OPT_CONNECT_TIMEOUT failed'); } if (!$mysqli->real_connect('localhost', 'my_user', 'my_password', 'my_db')) { die('Connect Error (' . mysqli_connect_errno() . ') ' . mysqli_connect_error()); } echo 'Success... ' . $mysqli->host_info . "\n"; $mysqli->close(); ?>
Object oriented style when extending mysqli class
<?php class foo_mysqli extends mysqli { public function __construct($host, $user, $pass, $db) { parent::init(); if (!parent::options(MYSQLI_INIT_COMMAND, 'SET AUTOCOMMIT = 0')) { die('Setting MYSQLI_INIT_COMMAND failed'); } if (!parent::options(MYSQLI_OPT_CONNECT_TIMEOUT, 5)) { die('Setting MYSQLI_OPT_CONNECT_TIMEOUT failed'); } if (!parent::real_connect($host, $user, $pass, $db)) { die('Connect Error (' . mysqli_connect_errno() . ') ' . mysqli_connect_error()); } } } $db = new foo_mysqli('localhost', 'my_user', 'my_password', 'my_db'); echo 'Success... ' . $db->host_info . "\n"; $db->close(); ?>
Procedural style
<?php $link = mysqli_init(); if (!$link) { die('mysqli_init failed'); } if (!mysqli_options($link, MYSQLI_INIT_COMMAND, 'SET AUTOCOMMIT = 0')) { die('Setting MYSQLI_INIT_COMMAND failed'); } if (!mysqli_options($link, MYSQLI_OPT_CONNECT_TIMEOUT, 5)) { die('Setting MYSQLI_OPT_CONNECT_TIMEOUT failed'); } if (!mysqli_real_connect($link, 'localhost', 'my_user', 'my_password', 'my_db')) { die('Connect Error (' . mysqli_connect_errno() . ') ' . mysqli_connect_error()); } echo 'Success... ' . mysqli_get_host_info($link) . "\n"; mysqli_close($link); ?>
The above examples will output:
Success... MySQL host info: localhost via TCP/IP
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