hook_schema_alter

  1. drupal
    1. 6 core.php
    2. 8
    3. 7
Versions
6 – 7 hook_schema_alter(&$schema)

Perform 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.

Related topics

Code

modules/system/system.api.php, line 2991

<?php
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.',
  );
}
?>