2 Replies Latest reply on May 17, 2016 1:05 PM by Nicholas Lewis

    Data Connections: Multiple Parent Tables

    Nicholas Lewis

      Hi All,


      I have an access database that is based around two main parent tables. Those are the personal information tables and the date table (Cannot share too much in terms sending anyone files etc because of confidentiality).


      We have two major parent tables because we needed the personal info to allocate records but, also some events occurred on different dates that there were no other types of events in one table vs the other (most days certain events occurred but on other days when those events didn't happen for some individuals, there were measurements that did happen). The personal info was used to be able to assign a single recognizable name to all tables and events because we are importing data from about 5 different sources and they all aggregate the names differently. Then the master calendar because, we could always have all dates with the master calendar per say and then overlay data regardless of events not occurring on exactly the same day always. This is very easy to reconcile in microsoft access and in our original  excel powerpivot model. However, now I am having trouble with this in Tableau. I have two major tables that I need to relate to each other and overlay but, I cant reconcile the data correctly.


      I'm trying to create the tableau equivalent of having two child tables both capable of left joining to two different parent tables. I need to see how the events leading up to a measurement seem to have influenced that measurement. I'm stuck with only being able to connect them to one parent table ( name/personal info) and having the records show up in the preview box but, they aren't listed correctly. It will show 5 or 6 of the same repeated record with then different values from the other table I'm attempting to connect it with.


      (I'm editing this after posting) - I think a could breakdown would be this: Parent tables are 1) Personal Info 2) Calendar, Child tables are 1) Daily events 2) Measurements. One major hurdle will be this: there are multiple records in the daily events table. There is one record for the FULL day (this is an actual column) and then multiple records breaking down the sub-events that occurred in that day DRILL. This makes it challenging for the overlay unless in the connection I can filter out the sub-events and have only the full day records.


      My most previous attempt was calendar table left joined to both tables for date and then link the name ID between the two tables. However, the proper values do not overlay with the proper names. I have data from one table in the same row as someone from the other table.


      Any help would be greatly appreciated.