2 Replies Latest reply on May 10, 2013 4:08 AM by giles.somers

    How to avoid losing blank data when joining?

    giles.somers

      Hi

       

      I have a data set that I plan to update every so often.

      As part of the project, I want to join in list that I've generated separately.

       

       

      Say it's like this:

      Name:     Car:     Car colour:  

      Bob         Rover     Red

      Jane        Lotus     Black

      Peter       Mini       Blue

      David       VX         Red

       

      and I'm adding in my separate column using Name to join

       

      Name:     Car:     Car colour:   Age:

      Bob         Rover     Red           4

      Jane        Lotus     Black         7

      Peter       Mini       Blue           2

      David       VX         Red           11

       

      the trouble is, every now and again, a new name will be added to the list and I wont know what initially

      Name:     Car:     Car colour:  

      Bob         Rover     Red

      Jane        Lotus     Black

      Peter       Mini       Blue

      David       VX         Red

      Lisa         Austin    White

       

      My join sheet will only be

      Bob          4

      Jane         7

      Peter        2

      David       11

       

      So when I join it in to bring in age, any new names that I've not generated age for will be lost

       

      In other words, is there a way to 'join' data that will leave lines blank/null if it cant find a match rather than in effect filter them out??

       

      I have tried using IIF(ISNULL(... to turn the nulls into a value, but join looks back at the original blanks.

      I'm hoping it's possible to have Tableau join where a match is available and leave lines where not rather than remove them - or is there a way to set added tables to show all of this filtered out blank non-matching data?

       

      Thanks in advance for any help