Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd12f379c20894ea63bdd1d05c0b4177c35b54c43205fce0edf7eb88a10035a7f' 
  AND token = 'u9GgCr2CD6BkLfJsq3/++66j46QLd4tyrvP6/msUd44=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}