PDO_MYSQL is a driver that implements the PHP
Data Objects (PDO) interface
to enable access from PHP to MySQL 3.x and 4.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.
Внимание
Beware: MySQL tables do not support transactions by default. When
writing transactional database code, MySQL will pretend that a
transaction was initiated successfully, even when no transactional
support is present. In addition, any DDL queries issued will implicitly
commit any pending transactions.
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 mysql-specific attributes with the postgres 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.
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.
Пример 1. Forcing queries to be buffered in mysql
<?php if ($db->getAttribute(PDO_ATTR_DRIVERNAME) == 'mysql')) { $stmt = $db->prepare('select * from foo', array(PDO_MYSQL_ATTR_USE_UNBUFFERED_QUERY => true)); } else { die("my application only works with mysql; I should use \$stmt->fetchAll() instead"); }