Thanks all for your replies !
I realised I was not clear in my first post.
I'm not trying to ''batch rename'' fields, as supposed by 6233638.
I'm trying to define categories with an IfElse() expression.
Example:
I have this single album Feel by Ty Segall. Using the RateYourMusic website genre structure, I tag this album with the following genres:
Neo-Psychedelia
Indie Rock
Starting from the first level (Main Genre) in the genre structure, the whole ''genre lineage'' for this album would be:
Rock -> Psychedelic Rock; Alternative Rock -> Neo-Psychedelia; Indie Rock.
It's a simple 3 level case.
In my library, I use the standard field [Genre] to assign last level genres to my albums. I also use a custom [Main Genre] field to assign first level genres to my albums.
So, in this case, these fields would have the following values:
[Main Genre] = Rock
[Genre] = Neo-Psychedelia; Indie Rock
I don't use any other fields for intermediate level genres (it's already crazy enough...).
So, I would like to create a view to drill through the genre levels, using the IfElse() function or any other method.
In an attempt to create such a view, I would use the following expression to retrieve the second level genre from the [Genre] field:
IfElse(IsEqual([Genre], Neo-Psychedelia, 8, Psychedelic Rock, IsEqual([Genre], Indie Rock, 8, Alternative Rock)
For that Ty Segall album, both statements in the IfElse() function are true, but only the first one is catched by MC.
So, this album only appears under Psychedelic Rock, while it should also appear under Alternative Rock (as shown in the attached picture).
So it's probably an IfElse() limitation...
I will try the solutions proposed in this thread and report back.
Thanks again !