Tableau Server 8.0,Redshift

Question

I am launching a Tableau application that runs on Tableau Server using live connections to Amazon Redshift database. The data is being updated everyday.

When I connect to the server and enter the application via web browser for the first time, the displayed data is not the most updated there is ( there is a date displayed on each dashboard).

After the dashboard is loaded I hit the Refresh button and the data is updated, then I enter the same application from a different browser ( from the same user) and the displayed data Is the data before the update.

I don't want for the cache to be erased for each display of dashboard because performance is Impotent, I just want Tableau to get the most updated data for the first Time I enter The application

Thank you

Answer 1

This is Tableau Specific cache setting, and the best way to do that is to set cache expire in defined interval such as 24 hours. but in general this is very independent of database. You can dig into tableau and find out the specific menu option for doing that, if that's what your looking for.

Regards

Maysam

Answer 2

You can add a refresh to the link itself if you want to force a new refresh.

something like this

http://tabserver/views/Date-Time/DateCalcs?:embed=yes&:refresh

See: http://onlinehelp.tableausoftware.com/v7.0/server/en-us/embed_list.htm

On the other hand, if you want lets say a daily refresh on initial load... you could write a script that pulls down a dashboard with refresh true and then republishes it daily. Just google a bit on tabcmd.

Answer 3

You need to understand that the "refresh" button on tableau does not mean Tableau server will pull data again from backend database, say, RedShift, it simply refreshes the data from Tableau server to your browser.

Tableau server actually consists of an internal database called VizSQL, which performs well for interactive big data analysis. So, when you hit the refresh button on tableau, it refreshes the data from VizSQL to your browser. Since the data in VizSQL has not been updated with the newest data in your backend DB, you still see the old data.

If you want to refresh the data from your backend DB to VizSQL, basically you have 2 choices:

1. Setup periodic extract refresh on tableau server, then the data in VizSQL will be synced from your backend DB periodically according to your schedule
2. Use tabcmd (a command line tool distributed together with Tableau server) to refresh the extracted data, you can do it on demand