One report for multiple users simultaneously

[aj1973]

Hi Community,

I have 2 questions regarding performance of a report in the service that is being used simultaneously from up to 20 users at the same time. The connection mode of this report is a Direct Query mode to 4 tables (from avarage to big).

Questions:

1. How is the performance of the report especially when there is a change in the Tables at the time of manipulating it?
2. If there is a performance issue would it be better to create a View out of the 4 Tables in the Database and then use Direct Query mode to connect to that View?

I know that this is something that needs to be tested that's why I am wondering if someone has done it already.

Thanks in advance.

[lbendlin]

The usual database locking rules apply. Table locks, row locks, optimistic vs pessimistic locking etc.

[lbendlin]

All you do is add another layer between the user and the data source.

[aj1973]

It sounds like you took me to another level of discussion.

All I care about is how the report would act when 20 users are visualizing it at the same time. I know for Import mode wouldn't be a problem but I wonder for DQ when the data source is updating at the same time 

[lbendlin · Accepted solution]

If you use Direct query then all optimizations need to be done at the data source.  Index maintenance, statistics up to date etc.  You will also want to tell the db owners to expect many concurrent connections.

Using Views will not improve things, it will likely make it worse.

If, however, you switch to Import Mode then all these problems go away magically as the data is cached in the Power BI service and it doesn't really matter any more how many users are looking at it.

[aj1973]

@lbendlin 

Using views will likely make it worse! What do you mean? Like how worse if I still use DQ to connect to that view?