1 Reply Latest reply on Nov 26, 2016 6:48 PM by Bora Beran

    Able to inner join, left join, right join but not outer join!!

    Sunil Sharma

      Hi All,

       

      I am a beginner in Tableau, I have connected tableau to My SQL database. I am able to perform a left join, right join, inner join but not outer join and I am unable to figure out the reasoning behind this.

      1. I have checked the data types  for the fields I am joining on they are same.

      2. I am not using custom SQL.Capture.JPG

       

      Thanks

      Sunil

        • 1. Re: Able to inner join, left join, right join but not outer join!!
          Bora Beran

          I don't think that MySQL supports full outer join. But you can do this by yourself in custom SQL using two joins and a UNION.

           

          A full outer join keeps all the records from both tables and it is equivalent of combining results from a left outer join and a right outer join then getting rid of the duplicates.

           

          So something like this

           

          select TableX.ID, ColA, ColB from TableX right join TableY on TableX.ID = TableY.ID

          UNION

          Select TableY.ID, ColC, ColD from TableY right join TableX on TableX.ID = TableY.ID

           

          Union will get rid of the duplicates for you.

           

          I hope this helps.

           

          I am not sure why this option is offered in the UI.

           

          Bora