PDOATTREMULATEPREPARES

PDOATTREMULATEPREPARES refers to the PDO attribute used to control whether prepared statements are emulated by PHP or executed by the database driver. In PHP’s PDO extension, this attribute is named PDO::ATTR_EMULATE_PREPARES. When enabled, PDO simulates prepared statements on the client side; when disabled, it relies on the database server’s native prepared statements.

When ATTR_EMULATE_PREPARES is true, the query with placeholders is constructed and parameter values are bound within PHP before being sent to the database. This means there is no server-side preparation step, and the database receives a fully formed statement. When it is false, PDO sends the statement for the database to prepare and then binds the parameters, allowing the server to handle preparation and typing.

The default value is driver-dependent, but many drivers ship with emulation enabled by default. For example, pdo_mysql commonly defaults to true, whereas you can override this at runtime. Checking the current setting with getAttribute(PDO::ATTR_EMULATE_PREPARES) helps determine behavior for a given connection.

Trade-offs exist: emulated prepares can offer portability and sometimes faster startup for single-use statements, but they may not support all database features and can reduce performance for repeated executions. Native prepared statements can improve security and performance on the server side and preserve database-specific typing and features.

Common usage: to enable native prepared statements, set the attribute to false in the constructor options or via setAttribute. For example: new PDO($dsn, $user, $pass, [PDO::ATTR_EMULATE_PREPARES => false]); or $pdo->setAttribute(PDO::ATTR_EMULATE_PREPARES, false).

See also: PDO, prepared statements, PDO drivers.