Oct 12 2015

Yes, Virginia, You Can Switch a Multi-Source Universe Back to Single Source

Categories: IDT,Universe Design Dave Rathbun @ 10:07 pm

What’s the first decision you have to make when creating a new universe with the Information Design Tool (IDT)? You have to specify if you want a single-source or multi-source data foundation. Once that selection is made, it cannot be changed.

Well, sort of.

We had an odd performance challenge with a particular universe. It seemed that when it was created, the developer thought they might want to eventually (perhaps) use multiple sources, so they went ahead and created a multi-sourced data foundation. But the project never ended up needing a second data source, so for over a year they’ve been using a single-source multi-source universe. (Did you follow that?) As a diagnostic tool, I thought about recreating a new universe as a single-source data foundation and resetting the various reports and dashboards so they would use the new universe. That would have been a lot of work, and with no guarantee that it would fix anything, much less have an impact on the issue.

Then I wondered to myself, what if I could figure out a way to “downgrade” the existing multi-source universe to a single source? That way I could still test my theory that our data federator engine wasn’t working as well as it should without having to re-point each report and redo each dashboard.

“spoiler alert” … it worked. 🙂 I was able to convert a multi-sourced universe to a single-sourced version without impacting the reports and dashboards, and we’ve been running on that version ever since.

How was it done? Well, I’m working on a presentation for the local DFW ASUG chapter meeting this coming Friday, and once I have that done I’ll post the details here as well. You’ll just have to wait a few days. 😛

Update: I won’t be presenting at the DFW chapter meeting after all, but I will still be posting this solution soon, hopefully next week.

Secondary note: I have also done the process in reverse… converted a single-source universe to a multi-sourced version, but with significantly more work involved. If you have a large number of reports, however; it may be easier to rework the universe and not have to re-point every report. Time will show if I’m successful or not…

6 Responses to “Yes, Virginia, You Can Switch a Multi-Source Universe Back to Single Source”

  1. Comment by Nick

    That’s a biggie….converted multi to single? Sell it to SAP…

  2. Comment by Dave Rathbun

    Nick, it’s not a coded solution, just a series of steps. We’ve just recently completed the second such conversion and it didn’t go as well… 🙁 I think the technique is sound, but apparently it’s not 100% fool-proof.

  3. Comment by Anupam

    hello,

    well that’s really interesting !!!

    can you share the steps, how you did that ???

  4. Comment by Dave Rathbun

    I posted a follow-up with the notes on how it was done.

    http://www.dagira.com/2015/11/05/downgrading-from-multi-source-to-single-source/

  5. Comment by Sarah

    Hi Dave
    Would you say that a multi-source universe could impact performance of a universe?
    I have been asked to investigate a universe that is multi-source, but doesn’t need to be. I am thinking one of the points to make is that it is multi-source but seeing as how they are only using one source I’m not sure it’s making any impact?
    Does that make sense??

  6. Comment by Dave Rathbun

    Yes, it has an impact. When you create a single-sourced universe the server connects direct to the data source. When you create a multi-sourced universe, even one with only one source, you have to go through the Data Federator service, which adds an extra layer.

    As you do your investigation, I would love to hear if you’re having other issues.