SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '680bb910881fc65cf0dcfef48b548d9649108ea183c16c4f252acc823ea39c71' 
  AND token = '1xHCwPLFsW1z4OcWxvRffrI3F4GiGrO9y5HiYWUAzz4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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