PDOsetAttribute
PDO::setAttribute is a method of the PHP PDO class used to configure the behavior of a database connection by setting a specific attribute to a given value. It is commonly invoked after creating a PDO instance to tailor how operations are performed and how errors are handled.
The method signature is public bool PDO::setAttribute(int $attribute, mixed $value). It returns true on success. If
Attributes control aspects such as error reporting, fetch mode, and how statements are prepared. Common attributes
- PDO::ATTR_ERRMODE: controls error handling (e.g., PDO::ERRMODE_EXCEPTION to throw exceptions).
- PDO::ATTR_DEFAULT_FETCH_MODE: sets the default fetch mode for query results (e.g., PDO::FETCH_ASSOC).
- PDO::ATTR_EMULATE_PREPARES: controls whether prepared statements are emulated by the driver or executed by the database server.
- PDO::ATTR_AUTOCOMMIT: enables or disables autocommit behavior where supported.
- PDO::ATTR_STRINGIFY_FETCHES: converts numeric values to strings when fetching results.
- PDO::ATTR_PERSISTENT: enables or disables persistent connections in supported drivers.
$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
This configures the connection to throw exceptions for database errors. Another common example:
$pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
This sets the default fetch mode to return associative arrays.
- Not all attributes are supported by every driver; some may require reconnecting the connection after changing.
- If an invalid attribute or value is supplied, a PDOException may be thrown, especially if ERRMODE_EXCEPTION