SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cfc756060820b9437de09bdf1d57e88962ba6dcc9a1377238f693ae4e8b556d9' 
  AND token = 'pKGBsnWaqw46uAhsXJEJu6WbC92pcSEWKCTGukDWGBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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