PDO & Doctrine DBAL Cache Adapter

Version: current
Edit this page

PDO & Doctrine DBAL Cache Adapter

The PDO and Doctrine DBAL adapters store the cache items in a table of an SQL database.

Note

These adapters implement PruneableInterface, allowing for manual pruning of expired cache entries by calling the prune() method.

Using PHP PDO

The PdoAdapter requires a PDO, or Data Source Name (DSN) as its first parameter. You can pass a namespace, default cache lifetime, and options array as the other optional arguments:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
use Symfony\Component\Cache\Adapter\PdoAdapter;

$cache = new PdoAdapter(

    // a PDO 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. DBAL Connection are lazy-loaded by default; some additional options may be necessary to detect the database engine and version without opening the connection.

Using Doctrine DBAL

The DoctrineDbalAdapter requires a Doctrine DBAL Connection, or Doctrine DBAL URL as its first parameter. You can pass a namespace, default cache lifetime, and options array as the other optional arguments:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
use Symfony\Component\Cache\Adapter\DoctrineDbalAdapter;

$cache = new DoctrineDbalAdapter(

    // a Doctrine DBAL connection or DBAL URL
    $databaseConnectionOrURL,

    // 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 = []
);

Note

DBAL Connection are lazy-loaded by default; some additional options may be necessary to detect the database engine and version without opening the connection.

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.