Showing posts with label effect. Show all posts
Showing posts with label effect. Show all posts

Thursday, March 22, 2012

Distinct Function

Hi All,

I have used Distinct function in my mdx query to remove duplicate
values.

I want to know what performance effect it will have on execution of
query.

With large volume of data query is taking more time to execute with
Distinct function. If we remove it it is taking less time.

Any inputs is appreciated.

Raghu

Depends on the query, but usually it has no effect on the performance. Distinct function doesn't look at cell values - it dedups tuples from the set. And if it is placed on the axis of SELECT query, then before getting cell values, the AS engine performs Distinct internally anyway. So it would be interesting to see your exact scenario to understand why you see performance difference.