Plugin needed: search an (excel) database (select values, post results)

Hi,

Looking for a plugin which enables me to search in a database.

Basically, I have 3 values. Let’s call them “shop”, “product” and “price”.

I want people to search for a product and perhaps shop. It will either show me the price, for that product at the selected shop, OR all shops and all their prices. More flexibility is welcome.

Now, there’s a second requirement (not a must have, but a nice to have).

We want people to enter an X amount. Like, “reduction amount”. For example if one says “20” the prices shown should be price-20.

Is there something out there which can (partly) facilitate this?