1. I would like to know the most efficient way to do this as well. Brian?
I did it recently to set the [DSP] field using;
If(math( Isequal([Media Type], Audio, 1) & Isequal([File Type], flac, 1) ), HDPlayer, Player)
See context over here:
https://yabb.jriver.com/interact/index.php/topic,118926.msg822852.html#msg822852So you would use something like
math( Isequal([a], 0, 1) & Isequal(c, 1, 1) )
as a test condition. But there must be a better way. I couldn't get anything else to work though.
EDIT: Oh wait, this is just a Search isn't it, not using the Expression language, as in my example for tag on import. In that case, just the following will work;
[a]=0 [c]=1
But I'm pretty sure your original will work as well;
[a]=0 AND [c]=1
It's described under "Grouping and Combining" in this article:
https://wiki.jriver.com/index.php/Search_Language2. [Disc #]=[]
You can learn some of these things by setting up the condition in any "Set rules for file display" dialogue, and then clicking the "Import/Export" button. That will show the long form of the condition.
So "Disc #" "is" "" (a blank field) converts to [Disc #]=[]