Forum Discussion
PBRS March Update breaking existing RDL reports that use LOOKUP function
The changelog should be updated soon but to answer your question yes this build addresses the nested Lookup function expression errors as well as several other bug fixes.
I just wanted to confirm that the latest build:
Version 1.2.6690.34729 (Build 15.0.2.402)
Does indeed fix the issues we were having. At this point, we are going to be moving this to our produciton instances, as it has passed all of our internal regressions.
mgmeyer, it looks like there are some more bugs we have identified with the RDL/Paginated reports in this latest March update of Power BI Report Server
When we use an aggregate function in a page footer, we get an #Error message on the new version. On the old October version this worked fine.
Code example:
="Market(s): " + IIF(Parameters!P_MA.Count = Sum(Fields!ParameterLevel.Value, "P_MA_Param"), "All", Join(Parameters!P_MA.Label, ", "))
We were able to work around using a variable:
="Market(s): " + IIF(Parameters!P_MA.Count = Variables!MarketAll.Value, "All", Join(Parameters!P_MA.Label, ", "))
But if we need to update all reports for this bug, it becomes an issue. Were there some regressions that got missed when building this new release? Looking at the change log, there isn't a lot of changes to the RDL/Paginated reports, so it is surprising to find so many breaking issues.
Thanks Ben for the update, we are actively looking into the issue and hope to have a fix soon. To your question around changes there we changes that do impact RDL reports however most of the them were infrastructure related.
- Awesome.
If there are any log files, or stack trace files, that I can send let me know. More than willing to help out troubleshoot. 
Is this a general issue. In other words: the "Lookup" functions don't work at all in this PBRIS March 2018 release.
My customer has some 15 reports using this kind of functionality.
Hard to say.
I have many reports that use lookup. Some of them have no issues. Some of them have issues. I can't exactly tell what causes the #Error, but it seems like if the lookup is used in conjunction with anything else, it fails.
Best thing I can say to do is test it out. Install the update on a test instance, and load up your RDL files. Initialy, our plan was to spot check reports, since it didn't seem like there was any real changes around RDL reports in this release. But seeing as how we have found these breaking issues, we are going through the process of evaluating all 180 reports we have on our system.
BenMackin Thank you for your feedback. We used the "Lookup" function to display the data in conjuction with other data sources data, and used in the sorting of the tables/matrices as well. Both sorting and display caused issues in all our reports.
mgmeyer We decided to rollback to the October 2017 version, which wasn't a simple uninstall of the March version, and a re-install of the October version. It seemed that the "ReportServer" database scheme was changed as well by the "March version" because the PBIRS/SSRS service couldn't connect to the "ReportServer" database anymore. After a restore of the "ReportServer" database with a back-up just before the upgrade everything was working again.
- Could you confirm that the "March version" indeed applied some changes to the "ReportServer" database scheme.
- When will a patch be available for the reported issues so far?
BR Frank