Tableau Performance Tips #7 : Prefer to use a one row datasource to display static metadata informations

A problem of choice

Tableau does not have really customisable buttons. I mean you can put image on your dashboard but you cannot display the text you want with the formatting you want like that.
One easy wait to put static metadata that will explain your dasboard to your users/collaborators is to create a view with a constant (like « i » for information)  change it to a font-awesome or webddings font and use the tooltip in the view. Indeed tooltip is a place where you can write text and format it as your want : Great … BUT…

If your use a big datasource as the datasource for your constant your can have some issue depending on your target datasource technology and version.

When does the problem become serious ?

Depending of the technology and even versions of the datasource you will request, you could have or not a performance issue with such view.

So when performance issue have most chance to appear :

  • If you have joins and/or where clause in the generated query
    • because of security for exemple
    • because an inner join in the physical layer
    • because of a filter shared on the datasource
  • If you have source without index (like big-query, or AWS athena)
  • if you have a complex view in the datasource (like you can have in SAP HANA or a complexe SQL View)

Conclusion

Like with the Tips #4, using a simple one row datasource is the best performance choice in case tou need a simple constant that will help you to display metadata in a tooltip.