Trying to compare two dates cant figure out what im doing wrong.

I may not be grasping the whole concept. (I know nothing of DAX or PQ.)

I created a Table in CURRENT DATA and array entered this formula in D3. Your formula above suggests you want to work with Tables. If you aren’t familiar with array-entered formulas array enter means the formula must be committed from edit mode by simultaneously pressing and holding down Ctrl and Shift while hitting Enter.

Formula:

Please Login or Register  to view this content.

If you have thousands of rows this may not be practical. If you are not aware of it array formulas are resource hungry. Too many of them will slow your workbook.

If you encounter problems with this formula are you open to helper columns? They can be hidden or put out of view (to the right?).

Row\Col	A	B	C	D	E	F	G	H
1	CURRENT DATA				WANT TO SEE
2	Date	Source	Revenue	Column1	Date	Source	Revenue	Yesterdays Revenue
3	7/31/2017	home depot	50	100	7/31/2017	home depot	50	100
4	7/30/2017	home depot	100	null	7/30/2017	home depot	100	null
5	7/31/2017	macys	100	50	7/31/2017	macys	100	50
6	7/30/2017	macys	50	null	7/30/2017	macys	50	null

Millions?

I hesitate to suggest this. It is all I have.

Not sure how this is going to work. You can try it. It is non array and looks at all 1,048,576 rows. Even with the very limited data in your workbook it took a little over one second to calculate. In D3

Formula:

Please Login or Register  to view this content.

With that much data to crunch I am not sure what else I can offer.

Row\Col	A	B	C	D	E	F	G	H
1	CURRENT DATA				WANT TO SEE
2	Date	Source	Revenue	Yesterdays	Date	Source	Revenue	Yesterdays Revenue
3	7/31/2017	home depot	50	100	7/31/2017	home depot	50	100
4	7/30/2017	home depot	100	null	7/30/2017	home depot	100	null
5	7/31/2017	macys	100	50	7/31/2017	macys	100	50
6	7/30/2017	macys	50	null	7/30/2017	macys	50	null

I over complicated this.

Try

Formula:

Please Login or Register  to view this content.