The MEH database has a complex data model. I can see there is data available in FMH_V_DATA, but its difficult to read. Let me elaborate
Let's say over the SFM UI, under User Variable Segments. I have a Customer Segment(V00), this segment has 10 user variables. Now, I want to find the value of these variables for a transaction that sits in TDR(Transaction Data Repository) database. Normally, I'd use the Explore tab but it has a lot of limitations, including the limit of number of visible transactions and the manual addition of columns.
I can see the MEH database has tables named FMH_l00_DATA_0 etc. but all these tables are empty. Only FMH_V_DATA seems to be populated.