Showing posts with label Assume referential integraty. Show all posts
Showing posts with label Assume referential integraty. Show all posts

Tuesday, 19 May 2015

what is Assume referential integraty?

In Database terms every row in fact table will contain a combination row in dimension table. Using this method only we build Primary and Forieng Keys for joining 2 tables.

The same option is even available in table under File Menu --> Data --> Assume Referential Intergrity.

If you unable this option for a .tds then tableau intelligently queries the tables and reduces the query retrieval time.


By selecting Assume Referential Integrity, you tell Tableau that the joined tables have referential integrity.
 
In other words, you are confirming that the fact table will always have a matching row in the Dimension table. 


Because that is true, Tableau doesn't need any information from the Dimension table in order to return these results. 


When you drag any fact column (Ex:AmountSales) field into the view, Tableau can simplify the query just with Fact Column.