public function DatabaseBackend::schemaDefinition

public DatabaseBackend::schemaDefinition()

Defines the schema for the {cache_*} bin tables.

File

core/lib/Drupal/Core/Cache/DatabaseBackend.php, line 421

Class

DatabaseBackend

Defines a default cache implementation.

Namespace

Drupal\Core\Cache

Code

public function schemaDefinition() {
  $schema = array(
    'description' => 'Storage for the cache API.',
    'fields' => array(
      'cid' => array(
        'description' => 'Primary Key: Unique cache ID.',
        'type' => 'varchar_ascii',
        'length' => 255,
        'not null' => TRUE,
        'default' => '',
        'binary' => TRUE,
      ),
      'data' => array(
        'description' => 'A collection of data to cache.',
        'type' => 'blob',
        'not null' => FALSE,
        'size' => 'big',
      ),
      'expire' => array(
        'description' => 'A Unix timestamp indicating when the cache entry should expire, or ' . Cache::PERMANENT . ' for never.',
        'type' => 'int',
        'not null' => TRUE,
        'default' => 0,
      ),
      'created' => array(
        'description' => 'A timestamp with millisecond precision indicating when the cache entry was created.',
        'type' => 'numeric',
        'precision' => 14,
        'scale' => 3,
        'not null' => TRUE,
        'default' => 0,
      ),
      'serialized' => array(
        'description' => 'A flag to indicate whether content is serialized (1) or not (0).',
        'type' => 'int',
        'size' => 'small',
        'not null' => TRUE,
        'default' => 0,
      ),
      'tags' => array(
        'description' => 'Space-separated list of cache tags for this entry.',
        'type' => 'text',
        'size' => 'big',
        'not null' => FALSE,
      ),
      'checksum' => array(
        'description' => 'The tag invalidation checksum when this entry was saved.',
        'type' => 'varchar_ascii',
        'length' => 255,
        'not null' => TRUE,
      ),
    ),
    'indexes' => array(
      'expire' => array('expire'),
    ),
    'primary key' => array('cid'),
  );
  return $schema;
}