Forum Discussion
relationship - direct query / import mode
In case we are doomed to use DQ and not the Vertipaq than pushing as much as possible to the source in DQ is always the best option, and optimize everything you can there. In DQ you don't use the Vertipaq storage engine of Power BI rather the storage engine of the data source, and in Power BI you only use the FE, which is 1 threaded, so best to go and optimize whatever you can in the data source (queries, indexes etc) and just let the Power BI be the visualization layer.
Hope that helps.
12 Replies
Hi alexng
Yes, it is called a composite model
See https://docs.microsoft.com/en-us/power-bi/transform-model/desktop-composite-models
I am a unpaid Power BI volunteer. Please click the thumbs up if you like me trying to helping you and click solved if it fixes your pronlem.If one table is in Dual and one is in Import - and of course the granularity is not m:m - than both relatioships exist simultaneously and the engine will use the one he fits best. It's reasonable to assume that if you will run a query that only consist of table that has a version in Import (Dual or Import) it will use the regular relationship. The only reason I'm not saying 100% is becasue there is no documentation on that. You can test your specific scenario and queries to verify.
Hope that answered your question.speedramps SpartaBI, thanks for your reply
I found that, in this case, regular relationship only apply to when
Fact table: Import
Dim table: Dual mode
(* : 1)
Im seeking a way to achieve the opposite because I want to import a large Dimtable connect to my fact table(direct mode). Thanks
Anonymous
Why don't make the dim Dual? If the fact is dual and you query something on both of them, than better if the dim will also be Dual. In this scenario you will have a regular relationship between both of them. WDYT?because I need the real-time data from Fact table(Direct Query)
old data from a Dim table, which is quite huge.
If I make the Fact table as Direct Query and Dim table as Dual mode, it seems that everytime when I update the report, the data from Dim table is linking to real-time data, which cannot help the performance. So i am trying to see if any way I can fetch only the import data from Dim table.
