Setting a Report-level default Data Source does not affect new Components, as it should

[skyler]

Per the "Replace the data source for a component, page, or report" documentation,

"Setting a data source at the page or report level has no effect on existing components in your report. Instead, new components that you add use the page or report-level data source by default."

I understand the first part and it works as it is written. But the second part - about new components using the report data source - i just have not found this to be true. The steps I am following:

1. [Setup] Have two Data Sources, Data Source A and B
2. Create a new Report, connect to Data Source A (it will create a default component connected to A)
3. Immediately, go into File > Report settings and change the Data Source to Data Source B
4. Create a new component via the "Add a Chart >" button (for instance, a table)
5. If i understand the above, it should be using the Report Data Source, Data Source B. But this is where i see it is still using Data Source A. And changing the Data Source at the Report Level from A to B or vice versa does not do anything. The new components seem to still have local component data source settings rather than using the report default.
   
   

I was ultimately trying to get a workflow going where i could have a report built upon a single data source that i could easily go into the data source menu to change from A to B (prod to dev, for instance). I think I will need to find alternative methods that work at the component level (i.e., using Select > Charts with this data source on page) or use the Copy Report UI and use the "New Data Source" selector.

I was excited by the promise of what was written in the documentation, however. Is this functionality working as expected? Did i misinterpret the documentation?

[sam8]

Love your thought process, and your detailed write-up!

It sounds to me like what you're doing should work. I can't see any reason that a new chart should still be connected to Data Source A once you've done step 3. Let me test this a bit and see if I can get anything to work, otherwise I'll file a bug and have our engineers take a look.

[sam8 · Accepted solution]

I just tested this and it worked exactly as you wanted it to 😕

That is, in step 5, my new chart was connected to Data Source B, even though the first chart was still connected to Data Source A.

Maybe this has something to do with your report, specifically? Is the page level data source set? Does the problem still occur if you use a fresh report, like I did for my test?

[skyler]

Thanks for getting back! I can confirm that it works and the behavior i described before no longer happens.

One comment for something I am not sure if it is working as intended:

• If i set Report Settings's default Data Source to "data B", should future charts be linked to the report default, or will it just locally assign whatever is currently set as default? Meaning, there is an "x" button next to the chosen data source. If i click it, it presumably disconnects the local config and changes to "Default (data B)" which means it will take on whatever the Report Default is. Without pressing "x" on each new chart, it will be stuck with data B even if i change it to data A. (does that make sense?)

So this is what i see by default, with the "x" to disconnect the chart from it's locally configured data source:

But i wish that I would see a [link to default] instead when a new component is created:

[sam8]

Right, that makes sense. This comes back to that first sentence - Setting a data source at the page or report level has no effect on existing components in your report. 

This pretty heavily implies to me that a component's data source is set when it's created. 

The advantage of this is that you can change the report/page data source without screwing up your report. The downside is that you can't easily change the data source for several components at once.

I really like your idea of setting a fluid / "default" data source (at the component level) that just listens to whatever the page or report is set to. Could be a worthwhile feature request!