function dblog_cron in Drupal 8
Same name and namespace in other branches
- 6 modules/dblog/dblog.module \dblog_cron()
- 7 modules/dblog/dblog.module \dblog_cron()
- 9 core/modules/dblog/dblog.module \dblog_cron()
- 10 core/modules/dblog/dblog.module \dblog_cron()
Implements hook_cron().
Controls the size of the log table, paring it to 'dblog_row_limit' messages.
File
- core/modules/ dblog/ dblog.module, line 63 
- System monitoring and logging for administrators.
Code
function dblog_cron() {
  // Cleanup the watchdog table.
  $row_limit = \Drupal::config('dblog.settings')
    ->get('row_limit');
  // For row limit n, get the wid of the nth row in descending wid order.
  // Counting the most recent n rows avoids issues with wid number sequences,
  // e.g. auto_increment value > 1 or rows deleted directly from the table.
  if ($row_limit > 0) {
    $connection = \Drupal::database();
    $min_row = $connection
      ->select('watchdog', 'w')
      ->fields('w', [
      'wid',
    ])
      ->orderBy('wid', 'DESC')
      ->range($row_limit - 1, 1)
      ->execute()
      ->fetchField();
    // Delete all table entries older than the nth row, if nth row was found.
    if ($min_row) {
      $connection
        ->delete('watchdog')
        ->condition('wid', $min_row, '<')
        ->execute();
    }
  }
}