SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa7deac3f4811da6bf0dab94ccb0f4ce70ed5639f03677b1f37b3860b9b88bca' 
  AND token = 'ojcuoME0ILHhPKQjq5jIFlqzDL8o29wWynrHtMobC5g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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