Teradata 16.20 might return wrong Query Results

This is just a short warning when you are upgrading to Teradata 16.20.

We recently upgraded from Teradata 15.10 to 16.20 and detected that some of our reporting queries returned with each execution a different result set. Sometimes the result set was correct, sometimes wrong.

After analyzing a little bit I found out that it’s related to Incremental Planning and Execution (IPE). Seems that something can go wrong with the execution plan when this feature is active. I will further investigate and give you an update if I can find out more about this issue. It’s quite possible that there is already a patch available. Any input is appreciated.

Since I turned this feature off, the result set is always correct (I am adding below query band as a pre-SQL to each Microstrategy report until this issue is fixed):

SET QUERY_BAND = ‘DynamicPlan=OFF;’ FOR SESSION;

I think this information might be useful for some of you experiencing this problem.

 Explanatory note: I just want to save you valuable time in case you experience this issue and have yet no solution. It’s definitely not meant to talk down Teradata.