I've had a look at the meeting minutes on confluence and I'm not entirely sure where "in-Butler catalog joins" is mentioned. Is this talking about datasets stored in multiple tables?

I suspect that this was a reference to “joining with reference catalog through butler”. But that meeting was years ago, and the Butler has been comprehensively redesigned since then; I see no value in keeping this ticket open.

I don't mind closing it but the minutes suggest this item was distinct from reference catalogs since reference catalogs were mentioned for DM-6658.