SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f093d61cc1ed2225a81c398ca36a28b971707148da87f46daf4634fa911eeef7' 
  AND token = 'Op1Q+rl5lY5v9uRYpMgtLvh3KRGymuRXci/0TZ3LIVI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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