There's lot's of threads on this topic, please be sure to search going forward as there's lot's of good information already covered - https://community.tableau.com/search.jspa?q=join+duplicate
Thanks for your help, Data blend is the way to resolve the issues, but I have not been able to find the information about data blending for data in same data sources.When I was trying with my same data, it can be done with one primary data source (Store) and with secondary data (Tue) but I am not sure how can add/link the tertiary (Wed),,,so on?
I'm not suggesting you use blending at all actually. In the linked support page, you'll see they outline a suggested method using a calculated field;
Create a calculated field that removes the duplicate values: You can create a calculation that divides the sum of the field being duplicated by the number of instances of the field that is causing the duplication.
For example, the Salary values are being duplicated by the number of instances of Employee ID for Wilson, Henry. In this case, in the view replace Salary with a calculated field that uses the following formula:
SUM ([Salary])/ COUNT ([Employee ID]).
You said in your original post you tried something similar but the numbers were still 'incorrect' - can you provide a more isolated example?
Below the solution I received from Tableau Support Team and it works with using a left join and adding one more key to join tables
found that the field 'servicetype' has been over counted in the underlying data after joining these tables. In order to resolve this issue, it will require to add 'servicetype' to join field, currently the join field used is only Store Id, needs to add 'Servicetype' to join field for table 'Wed' and 'Tue'
Seems I joined tables incorrectly.
Much appreciated your help.