MySQL Functions (PDO_MYSQL)
Introduction
PDO_MYSQL is a driver that implements the PHP Data Objects (PDO) interface to enable access from PHP to MySQL 3.x, 4.x and 5.x databases.
PDO_MYSQL will take advantage of native prepared statement support present in MySQL 4.1 and higher. If you're using an older version of the mysql client libraries, PDO will emulate them for you.
Beware: Some MySQL table types (storage engines) do not support transactions. When writing transactional database code using a table type that does not support transactions, MySQL will pretend that a transaction was initiated successfully. In addition, any DDL queries issued will implicitly commit any pending transactions.
Predefined Constants
The constants below are defined by this driver, and will only be available when the extension has been either compiled into PHP or dynamically loaded at runtime. In addition, these driver-specific constants should only be used if you are using this driver. Using driver-specific attributes with another driver may result in unexpected behaviour. PDO::getAttribute() may be used to obtain the PDO_ATTR_DRIVER_NAME attribute to check the driver, if your code can run against multiple drivers.
- PDO::MYSQL_ATTR_USE_BUFFERED_QUERY (integer)
-
If this attribute is set to TRUE on a
PDOStatement, the MySQL driver will use the
buffered versions of the MySQL API. If you're writing portable code, you
should use PDOStatement::fetchAll() instead.
Example #3 Forcing queries to be buffered in mysql
<?php
if ($db->getAttribute(PDO::ATTR_DRIVER_NAME) == 'mysql') {
$stmt = $db->prepare('select * from foo',
array(PDO::MYSQL_ATTR_USE_BUFFERED_QUERY => true));
} else {
die("my application only works with mysql; I should use \$stmt->fetchAll() instead");
}
?> - PDO::MYSQL_ATTR_LOCAL_INFILE (integer)
-
Enable LOAD LOCAL INFILE.
Note, this constant can only be used in the driver_options array when constructing a new database handle.
- PDO::MYSQL_ATTR_INIT_COMMAND (integer)
-
Command to execute when connecting to the MySQL server. Will automatically be re-executed when reconnecting.
Note, this constant can only be used in the driver_options array when constructing a new database handle.
- PDO::MYSQL_ATTR_READ_DEFAULT_FILE (integer)
-
Read options from the named option file instead of from my.cnf. This option is not available if mysqlnd is used, because mysqlnd does not read the mysql configuration files.
- PDO::MYSQL_ATTR_READ_DEFAULT_GROUP (integer)
-
Read options from the named group from my.cnf or the file specified with MYSQL_READ_DEFAULT_FILE. This option is not available if mysqlnd is used, because mysqlnd does not read the mysql configuration files.
- PDO::MYSQL_ATTR_MAX_BUFFER_SIZE (integer)
-
Maximum buffer size. Defaults to 1 MiB. This constant is not supported when compiled against mysqlnd.
- PDO::MYSQL_ATTR_DIRECT_QUERY (integer)
-
Perform direct queries, don't use prepared statements.
- PDO::MYSQL_ATTR_FOUND_ROWS (integer)
-
Return the number of found (matched) rows, not the number of changed rows.
- PDO::MYSQL_ATTR_IGNORE_SPACE (integer)
-
Permit spaces after function names. Makes all functions names reserved words.
- PDO::MYSQL_ATTR_COMPRESS (integer)
-
Enable network communication compression. This is not supported when compiled against mysqlnd.
Runtime Configuration
The behaviour of these functions is affected by settings in php.ini.
Name | Default | Changeable |
---|---|---|
pdo_mysql.default_socket | "/tmp/mysql.sock" | PHP_INI_SYSTEM |
pdo_mysql.debug | NULL | PHP_INI_SYSTEM |
Here's a short explanation of the configuration directives.
- pdo_mysql.default_socket string
-
Sets a Unix domain socket. This value can either be set at compile time if a domain socket is found at configure. This ini setting is Unix only.
- pdo_mysql.debug boolean
-
Enables debugging for PDO_MYSQL. This setting is only available when PDO_MYSQL is compiled against mysqlnd and in PDO debug mode.
Table of Contents
- PDO_MYSQL DSN — Connecting to MySQL databases