What's your source?

If you're connecting to a database you could do something like this:

SELECT GETDATE() as TimeStamp, CF1, CF2, CF3 FROM mytable

Then setup your extract to refresh daily and append to the existing data.

Use a timestamp like GETDATE() or NOW() in your SQL query, whatever the equivalent is for postgres. You're going to need to use custom sql or add a column to your view utilizing that function in order to bring it into Tableau.

In your database each day or as I suggested in my first post, look at

creating an incremental extract which would be appended to each refresh.

As I said earlier:

Use a timestamp like GETDATE() or NOW() in your SQL query, whatever the equivalent is for postgres. You're going to need to use custom sql or add a column to your view utilizing that function in order to bring it into Tableau.

Once you've added a timestamp to your query, you just need to setup an incremental refresh based off the timestamp column. Take a look at this - Quick Start: Incremental Extract Updates

In terms of automating the refresh to run every day - do you have Tableau Server or Desktop only? If you have server it's easy, just take a look at the refresh schedule options.

Desktop only - take a look through this - Tableau Automated Extractions Update Tool  or Tableau Automated Extractions Update Tool

Honestly, you might just be better to automate this as a job using a script to run every day outside of tableau and save the data into a new database table rather than relying on Tableau to do the scheduling / refresh component of this.

Tableau Desktop won't automatically refresh this on it's own, that's for sure. There's a couple of tools people here use as I've already linked to, otherwise you need Tableau Server (or Tableau Online) or a script of some kind.

Good luck!