Hey Mei Ling,
It can be a number of things
1. Are you working with a live connection or an extract?
2. What version of Tableau are you using?
3. How much underlying data is there?
I have tried both and live and extract connection.
Both also have the same behavior (slowness for the first sheet)
I am using Tableau 9.2.
I have a total of 7 tabs/ dashboards in a workbook.
There are a total of 20 data sources in it (with 12 connecting to live Excel files, and the other 8 are live DB connections).
The Excel file are pretty small, only having a sheet of data (max is around 50 records).
But the live DB connection is a bit large (each of them contain at least a million of records).
Each sheet are not using all data sources at the same time.
1 sheet might be using 2 / 3 data sources.
I can't upload the workbooks as there are confidential data (plus if I am creating a local extract for my DB source, it will be huge.)
But in general, do you experience opening the first sheet always took longer time?
Hey Mei Ling,
Waiting a couple of seconds for your first worksheet to show is really not bad when you are using more than 20 data sources.
I would create an extract of them all with the option 'Hide all unused fields' this may boost the performance a little.
Are you using any blending between the data sources? This also takes some more power from Tableau so taking a bit longer to load.
I agreed with you.
But I would like to know, in general why opening the first sheet always took longer time ?
Does Tableau cache all data sources ? even only 1 sheet is showing ?
Hey Mei Ling,
There are some tools provided by Tableau that help you check what going on in the background:
These will give you clarity on what's happening in the first few seconds when you open the first worksheet.
Thank you Matthias.
I will try some of advice given and see if it helps to explain this scenario.
Thank you for your information.
It seems there is a need of improve performance of the Dashboard. There are some suggestions
1) We can push back few of Calculations from Tableau to Database, if Very complicated & length of calculations syntax is longer.
2) Implementing "Context Filters".
3) Remove the unwanted Fields & Derived calculations.
4) If possible create a View at DB level (If you are using Oracle, create Materialized views).
5) Try to reduce the No. of Derived calculations.
6) Use the Extracts, If you are having the Snashsop data( i.e. Very detaied EX: Day level )& Your views Required at month level then Aggregate the data while creating the Extracts.
7) Try to reduce the No. of Views in the Dashboard.
I have hid all those unwanted fields.
I did use performance recording to check which views are taking longer time and to my surprise, some simple calculation (like a calculated field based on another calculated field) are taking long time to execute. I have changed some of them and loading time has reduced. Unfortunately not all can be changed..
Thanks for the suggestion though.