SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49217956c6db7aae214101e7c9d2eb7543dcf866eefbc5387781b9f0dad70697' 
  AND token = 'd6LiYqTtr0yf8crako9Qd956SH8/WM58hoXwwm9uyEY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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