My suggestion is to use a calculated field - either an IF or a CASE statement to do this. In any case, you're going to have to deal with manual updates at some point when something new appears in the data, even when there is new stuff in the source.
Are you working with a live source, or an extract of live data? If you're working with an extract, you could just alias the items in Excel and then bring them into Tableau, and you'd already have what you need.
I don't think it's a problem to use calculated field.
On the other hand, allowing multiple name into one alias will bring much much bigger trouble, when we input unexpected same arias.
That's quite difficult to track when that happens.
If you're working with an extract, you could just alias the items in Excel and then bring them into Tableau, and you'd already have what you need.
Could anyone elaborate for me on the statement above. If I am working with an extract, can I take that extract into Excel to perform further manipulations, and then bring that data back into Tableau? What then happens when the original source data changes and I need to refresh my extract?
I was referring to extract in the general sense - not a Tableau extract, but data from another source. As far as I know, you can't really take data from a Tableau extract and re-work it in Excel (well, not without extracting the .twbx and pulling the data out of the source, and it won't be in the same format that the original data was in).