SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2744f9fe2d07f38b97ce80b3b8b13966e48f5602ba02de847c4c5f486166e222' 
  AND token = 'rYtmZmGCkTTBjxJbVNYIvs8H57RaqKaEDXSoivUysJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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