Ok here's an admission. Table Calculations sometimes confuse the heck out of me. However I've developed a few little tricks I use to make life easier. Here's one I utilised in my latest Tableau Public viz.
Lets say you've been using the cool new Rank feature in Tableau 8.1 on loads of fields, but then you want to filter your data and NOT have the ranks recalculate. What do you do? There are probably many ways to skin this cat, however here's the one I used. It may not be the 'best' way, but I like it. As usual I'm going to use Superstore Sales data to demonstrate.
First I'm ranking all countries by four fields:
Ok good, and I've sorted by the rank of Discount to make the order clear. Now I tidy things up a bit and add a quick filter on country:
Now you see I've de-selected a few countries, and they have disappeared from the view, but the rank has re-calculated. That's expected behaviour, but in my case I didn't want the ranks to recalculate. So here's what I do to fix the rankings (I think of this like doing a copy and paste values in Excel when you want to stop the formulas from calculating).
First, put everything back in the filter.
Then hit CTRL+C
Open a new worksheet
and bingo I now have a new hard-coded data set from the clipboard!
This data set includes only four fields:
Measure Names - Rank of Discount, Rank of Profit, Rank of Sales, Rank of Shipping Cost
Measure Values - the original 'hard-coded' ranks for each
Number of Records
So now when I filter out countries, the countries disappear from the view but the ranks stay as they were:
and then this can be easily brought into a dashboard along with the main data set by using data blending on country.
And all's well that ends well.