SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8dadfa3db5ab5bb33ffd4a9768f068eae7c65cdcbd267b93c84a94be10c9ef16' 
  AND token = 'vKidIdqPcM5+adxhUUbxxq+75wN++QNDlSiq8b3JZcI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}