PDO & Doctrine DBAL Cache Adapter

This adapter stores the cache items in an SQL database. It requires a PDO, Doctrine DBAL Connection, or Data Source Name (DSN) as its first parameter, and optionally a namespace, default cache lifetime, and options array as its second, third, and forth parameters:

use Symfony\Component\Cache\Adapter\PdoAdapter;

$cache = new PdoAdapter(

    // a PDO, a Doctrine DBAL connection or DSN for lazy connecting through PDO
    $databaseConnectionOrDSN,

    // the string prefixed to the keys of the items stored in this cache
    $namespace = '',

    // the default lifetime (in seconds) for cache items that do not define their
    // own lifetime, with a value 0 causing items to be stored indefinitely (i.e.
    // until the database table is truncated or its rows are otherwise deleted)
    $defaultLifetime = 0,

    // an array of options for configuring the database table and connection
    $options = []
);

The table where values are stored is created automatically on the first call to the save() method. You can also create this table explicitly by calling the createTable() method in your code.

Tip

When passed a Data Source Name (DSN) string (instead of a database connection class instance), the connection will be lazy-loaded when needed.

Note

Since Symfony 3.4, this adapter implements PruneableInterface, allowing for manual pruning of expired cache entries by calling its prune() method.