lastnonempty & role playing date dimension

Hello,

I'm just curious if in case of a role-playing date dimention it's possible to somehow tell SSAS to use only one role for LastNonEmpty aggregate?

Like we have a fact table with a few date related members - such as TransactionDate, DateOpened, DateClosed etc.

All measures in this fact table are set to aggregate as LastNonEmpty & everything works just fine as long as only TransactionDate is linked to dimDate.

If any other dates are linked then LastNonEmpty doesn't work properly anymore & we get unpredictable results.

So if it possible to set ONLY TransactionDate to be used as LastNonEmpty & for all other dates just aggregate as sum?

Thanks!

It is always only ONE role-playing time dimension. The problem is, you cannot control which one it is. Sorry, but there is no way to tell directly to SSAS which one. You can keep reordering the cube dimensions in AMO until SSAS picks the right one. After that, if the order doesn't change - it will always use the same one (it is stable algorithm w.r.t. order of dimensions).|||

Cool - thanks for the answer - at least there's a way!

Now - AMO stands for Analysis Management Objects so how do I reorder cube dimensions in AMO?

Is the order in AMO the same as the order in which dimensions are displayed in the dimension usage section of VS?

I'm kind of confused how to move them?

|||If you look at the XML behind Create Cube DDL (or Alter Cube DDL) - the order of cube dimensions there is the one I am talking about.|||

I see what you mean...

so by "reordering the cube dimensions in AMO until SSAS picks the right one" - do you mean reordering just role playing date dimensions or ALL dimensions? I have 5 date related and a LOT more other dimensions so without some further guidance it's not clear to me how to handle all the possible combinations?

BTW is it a coincidence or a rule that the order in XML is the same as the order in which dimensions are displayed in 'dimension usage' pane of VS? Appears to be that way...

|||

> do you mean reordering just role playing date dimensions or ALL dimensions?

Reordering just the cube dimensions which are marked as Time within measure group. So it your case - it would be reordering 5 dimensions. There are really only 5 combinations here - just pick the dimension you want to do LastNonEmpty by and move it to the first, second, etc places. The rest doesn't matter.

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Could you please be a bit more specific as the XML file is rather large (20+K lines) & there's way to many places where dimensions are mentioned - one where they're defined, one where the relationships between measures & dimensions are defined - I moved things around there with no effect, third place is where aggregations are defined like:

<Aggregation>

<ID>Aggregation 5</ID>

....

<Dimension>

<CubeDimensionID>Maturity Date</CubeDimensionID>

</Dimension>

but there's so many of these so where exactly do I change the definition for the settings to apply?

Thanks!

|||Look for <MeasureGroups> tag. Then locate <MeasureGroup> tag which mathes your measure group. Then skip over <Measures> collection and go to <Dimensions> collection. This is where you should do reordering.|||

cool - thanks - I got it working!