SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '519aabdd01f0688b28660aea49832af23412bfd8fed593234a929454c9efbc8e' 
  AND token = '5FAP5zJBxhp3pGALLWdUnWQeJ4SuXQVm7687tGM2ZJo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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