Asp Sql - Check If Update Else Insert..

I'm using a database to store the products in a basket.

It's this scenario:
A visitor already has some products in his basket and wants add some new ones.

Now, first I want to check if the selected products aren't already in the database.

1. if they are -> update the product when the amount number is changed
2. if the product is not in the database then insert it.

I'm stuck at the point that I can't retrieve if the database is updated, so I can either stop the query or insert the new product.

Java has a statement like getUpdateCount(), but ASP/VBSCRIPT??

I want the fastest solution, i dont want to retrieve the data twice and compare them to check if it changed..