Delete from Multiple Tables using db_delete()

Question

How can we delete fields from multiple tables using db_delete() and INNER JOIN in Drupal 7?

Answer 1

You can't I'm afraid.

db_delete() takes a single string parameter to define which table the query is to be run against. There's no scope to provide more than one table at a time.

You can run any SQL statement you like, though, with db_query(), eg.

// Deletes all nodes and related author users...please don't actually run this!!
$sql = 'DELETE u, n FROM {node} n INNER JOIN {users} u ON u.uid = n.uid';
db_query($sql);

Answer 2

Yes, db_delete takes a single parameter. You have to call db_delete() multiple times to delete data from multiple tables. Please see the following sample code:

/**
 * Implements hook_menu_delete().
 */
function block_menu_delete($menu) {
  db_delete('block')
    ->condition('module', 'menu')
    ->condition('delta', $menu['menu_name'])
    ->execute();
  db_delete('block_role')
    ->condition('module', 'menu')
    ->condition('delta', $menu['menu_name'])
    ->execute();
}

Source link:
https://github.com/drupal/drupal/blob/7.x/modules/block/block.module
https://api.drupal.org/api/drupal/modules%21block%21block.module/7.x