Measures - some basic questions

Hey Experts,

I have a BEx Query that has a measure which includes SUMCT. This application isnt avalible to make a Universe.

So in my opinion the only solution is to create the measure in universe designer.

After I created a new measure I noticed that the SQL Editor isnt on hand. Is the editor not avalible because I work with SAP elements that have predifined table structures?

In the Select section I made a reference on my measure. This works fine.

<EXPRESSION>(@Select(Measure\Name)</EXPRESSION>

But when I want to make a calculation I get errors that the definition isnt correct.

Do somebody know how I can make for e.g. measure / sum(measure) *100 or sth. like that?

Regards

Jan