Seems like I found a solution and I'm pretty sure that the [DelimitedSplitN4K] was the cause of the problem (the catch all query might be a problem later when number...

I've tried all suggested solutions in the mentioned article - but they dosn't seem to have any huge effect on my problem.

tblCase contains 6043 rows and tblCaseOrderLine contains 12589 -...

I actually read the article, and have also added the OPTION recompile to the procedure - but I don't think it has any effect on the performance. The entire procedure...

Because of the Join with tblCaseOrderLines has been removed, I had to rewrite below AND-clause (was left out of the example for simplicity). DelimitedSplitN4K is a Table Valued function that...

Thanks for the suggestions. I've now implemented it, the way you described and it works very well.

Yes, you're right: CaseOrderLine (and other tables) are only used for filtering since loading of the entire case (including orderlines) is handled in code in the middle layer.

I'll try your...