I'm trying to create a join between two tables in Tableau Prep. One table only has two fields, User ID and Sales Channel. The other table has many more fields but also contains User ID's. I tried to create a left and/ or inner join to populate the larger table with the sales channel field. When I try to do this, I'm met with a large number of nulls and sales channel is only populated for the number of rows in the smaller table. How can I get Sales Channel to populate all of the rows based on the User ID criteria? (User ID is contained in every row of the large file)
@Lawson Medlen
Hi, I am understanding correctly: Does you user table (user id, sales channel) have all users in Sales Table?
If this is the case, and you are sure, every user id is in both tables, then the problem has to do with the Tableau Prep Interface. Basically, to speed up flow building, Prep samples data, so you may find that the join results shown in the UI seems to be not correct.
However, my recommendation, is that after the join, you add and output step (to a hyper or a published data source) and check the number of rows from Tableau Desktop (connecting to the published data source or hyper file).
If this post resolves the question, would you be so kind to "Select as Best"?. This will help other users find the same answer/resolution and help community keep track of answered questions. Thank you.
Regards,
Diego Martinez
Tableau Visionary and Forums Ambassador
