SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63c605137e1b5fd0a95f7c6df69d8099b3188c95038250eff2ec412120d24e2e' 
  AND token = '71/tqf3nDBn9Uy661tknua6Ng7SlQpvJ2bUe+Bv/COM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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