How can I update existing data in my database when importing?
You have data in your database, and you have an import file containing new or modified data that you want to use to update those existing records. For example, new prices. How can you use the import data to update the existing data?
In your Import Style, click on the Updates tab and choose the Update Existing Records radio button. then select the Key Field or Key Fields to match the imported data to the existing data, and choose which fields you want to update.
For more informaiton about importing and updating data, see the Importing Tutorial.