First, identify if that's the actual performance bottleneck in the query. More likely, there are issues with the way the query is written, with indexing (missing indexes, indexes with poorly chosen leading edges, non-covering indexes, etc.), with index/table fragmentation, and so on.
Yeah, I'll have to look into this more detailed. The annoying thing here is, that with Dynamics NAV queries we have almost no chance to write the query in a better way - NAV automatically "translates" its native programming language into SQL ...
For now I have porposed/prepared an index rebuild on that table to make sure fragmentation is not an issue here ...
As soon as I got the QEP I'll share it here.
Thanks a bunch so far!
Jörg A. Stryk
MVP - MS Dynamics NAV