Normally when you you open the Field Explorer / Database Fields, you see the tables and you know where exactly it came from the source(SQL).  However, there is this "combined" table listed done by my pre-decesssor (the table name is called something like "table1 PLUS table2"), I thought I could find this on the original source, but I could not find it.  This is odd, so there must be something to be learnt. 

 

Does anyone know how this is done? In this combined table, there is some field that exists but I could not find these data on the orignal table (before they were combined) I am using version 8.5.

 

Thanks!