function hook_schema_alter
7.x system.api.php | hook_schema_alter(&$schema) |
6.x core.php | hook_schema_alter(&$schema) |
Performs alterations to existing database schemas.
When a module modifies the database structure of another module (by changing, adding or removing fields, keys or indexes), it should implement hook_schema_alter() to update the default $schema to take its changes into account.
See hook_schema() for details on the schema definition structure.
Parameters
$schema: Nested array describing the schemas for all modules.
Return value
None.
Related topics
1 invocation of hook_schema_alter()
- drupal_get_schema in drupal-6.x/
includes/ common.inc - Get the schema definition of a table, or the whole database schema.
File
- documentation-6.x/
developer/ hooks/ core.php, line 725 - These are the hooks that are invoked by the Drupal core.
Code
function hook_schema_alter(&$schema) {
// Add field to existing schema.
$schema['users']['fields']['timezone_id'] = array(
'type' => 'int',
'not null' => TRUE,
'default' => 0,
'description' => 'Per-user timezone configuration.',
);
}