Forum Discussion
RELATED function does not work - is dual/import mode an issue or a "limited" relationship?
frittzy see below from the documenation on RELATED() and limited relationships. It appears that your hunch that this is due to using a dual-mode/composite model is correct.
https://docs.microsoft.com/en-us/dax/related-function-dax
https://docs.microsoft.com/en-us/power-bi/transform-model/desktop-relationships-understand#limited-relationships
Wow, my bad Anonymous... I read that article before I posted, then revisisted since I clearly missed something, and then missed it again. I'm still becoming 'fluent' in PBI language. I was reading 'cross source group' as different sources (sql, orcale, etc.), not different models (which I shoudl have known is what Composite meant). <sigh>
Anyway, that's a good question. My tables are going to be <20,000 records per table, which I'll have 6-7 "dual" mode tables now. Now my mind is going to "when should I use DQ/dual vs. Import"? I've researched that a bit and only with with Dual so working on PBI Desktop was faster. Considering I have the gateway running just fine, what should I be considering then when thinking about which model modes I'm using.
frittzy
My recommendation (and the recommendation I frequently see offered as "best practice") is that DirectQuery should be a last resort, to be used only when absolutely necessary (for instance if true "real-time" data is needed, or tables are so large that Import is not an option). Modeling issues aside, a report using DirectQuery is almost always going to be slower than one only in Import mode, because the source data needs to be queried every time a visual needs to be refreshed.
I would recommend taking a look at the "Benefits...", "Limitations", and "Import considerations" sections of the DirectQuery documentation.
https://docs.microsoft.com/en-us/power-bi/connect-data/desktop-use-directquery#benefits-of-using-directquery
I would always default to using Import mode only, unless there is a really good reason not to...