SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0cf7a23b4cbc0d1565d570aacd9a14113f470ba1450a75cb8592a949c035f2d6' 
  AND token = 'fAlbhCuDz9fYyBn7pOa/qbeai50INHCsgpxDBU/uEUk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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