Update mode values overlap previous data?

Thanks for stopping by to ask us a question! Please make sure to include:
- **What you're trying to do:**
I want to update values in google sheets but I don't know if it overlap the previous data or I have to clear all the spreadsheet and then update.
- **What code you've already tried**
I'm using this [documentation](https://developers.google.com/sheets/api/reference/rest/v4/spreadsheets.values/update).