function metatag_update_7001 in Metatag 7

Fix the "{metatag_config}.cid column cannot be NULL" error.

File

./metatag.install, line 860

Install, update, and uninstall functions for the metatag module.

Code

function metatag_update_7001() {
  $table_name = 'metatag_config';
  $field_name = 'cid';
  $field_spec = array(
    'type' => 'serial',
    'unsigned' => TRUE,
    'not null' => TRUE,
    'description' => 'The primary identifier for a metatag configuration set.',
  );
  $keys = array(
    'primary key' => array(
      $field_name,
    ),
  );

  // Before making any changes, drop the existing primary key.
  // Let's add a temporary unique key for cid so MySQL will let it go.
  // Hint taken from https://drupal.org/node/2064305#comment-7753197.
  db_add_unique_key($table_name, 'temp_key', array(
    $field_name,
    'instance',
  ));

  // Unforunately there is no API way to check if a primary key exists, so if
  // it doesn't exist the db_drop_primary_key() call will fail.
  try {
    db_drop_primary_key($table_name);
  } catch (Exception $e) {
    drupal_set_message('Caught an exception: ', $e
      ->getMessage());
  }

  // Rejig the field, and turn on the primary key again.
  db_change_field($table_name, $field_name, $field_name, $field_spec, $keys);

  // Finally, remove the temporary unique key because it's no longer useful.
  db_drop_unique_key($table_name, 'temp_key');
}