SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89c893127b3dbccfff6ce3f465c8551de622f54d865174ce4567286bbea95647' 
  AND token = 'ip2uVSs1mEhb2j3NAJAQ9gDmMc45RPQiEmqVSsYXhP8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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