SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a09b279e6d6263b27557d5b1c0a316275780415bc56bd4a571f9764efd635daf' 
  AND token = 'fcBOiUbcNVj4fiuMZxqaYz6l9Y2EJVYoHeaXUmPRVPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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