SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c901c0d8608796ff3137df5e1b08cc7ca1bfd49443245c6569785aa382cf15e' 
  AND token = 'gLRemk+6lIOGzEkOGjUjR4X2+xsKiPX/T1AzaPcNUYI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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