Filter Delegate Intermediate - This not that (1)

If you're not familiar with the basics of filter delegate, please refer to this article before continuing reading.

When you setup filter delegate, you can choose between "EQUAL TO" and "DIFFERENT FROM" -but what if you did both?

That gives you some great opportunities which has also been described in this blogpost by David Hollinworth. 

In this setup, the left-hand side table is setup with filter delegate on EQUAL TO customer, while the middle table is setup to DIFFERENT FROM customer.

That means that if you drill on e.g. Mens Hat in table on the left-hand side, you get a full list of all the customers who bought a Mens Hat on the right hand side.
(notice by the way that the middle table has been set to ignore filters on customers)

When you drill on Mens Scarf in the middle table, the list on the right-hand side shrinks significantly as you can see below:

Why is that? 

Well if you imagine that the first drill (from the left-hand side table) found a list of customers A, B and C and delegated those as a filter, the list on the right-hand side will now show customers A, B and C, because the effective filter is EQUAL to A, B or C.

Then you drill on the Middle table and it delegates a list of A and B (who bought the Scarf).
The delegated filter is DIFFERENT FROM A and B.

Now the "sum" of those 2 filters will end up being C.

So we end up with a list of those who bought Product A but DIDN'T buy Product B.

This could be your classic up-sale situation - someone came with a Mens Hat, and the salesperson was supposed to try and upsell Men's Scarf - but in some cases failed to do so.

There are many other scenarios - as the referenced blogpost mentions - basically it's a question of who did this but not that.

Will it be the same if we switch the sequence of the drills?

Well actually not as you can see from the screenshot below.

And it makes sense if you think about it. If we follow the explanation above, it would look like this:

First we say EQUAL TO A or B and then we say DIFFERENT from A, B and C

The "sum" of that is - well nothing.

Notice the nice touch, that the Empty result message for the right-most table has been set up to write:

All who bought Product A also bought Product B (100% SUCCES!!!)