SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a090b00732f0b2d8e83e7f1dc38657b5ab673d164d4241afd17d2246d12050d9' 
  AND token = 'yF7H+yDUGTHJbVQeiJj6DpyZD5KejBZJ5mZMOjVQOCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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