update an Excel spreadsheet with an sql query of a database

I am trying to compare two sets of data and update one from the other. My main database has approx 10000 items and their prices change constantly. It is an sql database. My website has about 500 products and I want to update those prices once a week using the prices contained in our master database. Ideally: I would export a list of the products on the website to a .csv file and import into Excel, with only the following fields: SKU, price and quantity. Then I'd have Excel query the SQL database for matches on each of those SKU's, with a return of price and quantity. I would then upload the updated list back to the website. What I need done is to have someone write the query that would check each record in my list of web products against my main database and update the price and quantity fields for each SKU that had a change. And secondarily, to then flag each changed record so we could then upload only those that were changed back to our website. We would then need instructions on how to set it up at our end and what commands our staff would need to execute to run this process each week.