I have been using SSRS2010 for a long time and only just decided to move to MS 2019 technology, so no changes to the rdl files just a new SSRS server. The first thing I noticed was the sort order in Tablix's was essentially in reverse order in some cases. I can run the same report in SSRS2010 and SSRS2019 pointing to the same 2019 SS database and the SSRS2010 sort order is same as the proc but the SSRS2019 is not the same order and in fact in reverse order in some scenarios in part. For example, if my data produced by the stored procedure was:
| Who | Fruit | How Many |
|---|---|---|
| Bob | Apple | 1 |
| John | Apple | 1 |
| John | Apple | 2 |
Then my report would display:
| Who | Fruit | How Many |
|---|---|---|
| Bob | Apple | 1 |
| John | Apple | 2 |
| John | Apple | 1 |
So even if my report dataset stored proc sorted on Who and not "How Many" it sorted "How Many" in reverse order. So essentially where my data had duplicates it sorted the duplicates in reverse order. In this example purely made up say there were 2 John's and I forgot to add the surname. In the real world it could be 2 corporate contacts of the same type so there is essentially no data loss in the report just a different order in presentation.
Is this a known issue. I know the workaround is to sort on more fields in the proc or sort in the tablix itself but why is this happening is there anything I can do like some default behaviour on the SSRS server I can twiggle with.