cancel
Showing results for
Did you mean:

Find everything you need to get certified on Fabric—skills challenges, live sessions, exam prep, role guidance, and more. Get started

Resolver I

## Which dax statement is more efficient?

Dear users.

I was wondering, while building a piece of DAX, if i could improve it or not. Below is a formula i use to calculate the sales in period 1, starting at P1 start and ending at P1 end.

`P1 Sales = CALCULATE([Sales];DATESBETWEEN(DateTable[Dates];[P1 start];[P1 end]))`

The second argument might lead to a table of e.g. 365 rows, if i have P1 start at Januari 1st, and P1 end at December 31st.

As i know the sales table ALWAYS ONLY has sales at the 1st of the month, i thought, why not have the second argument filtered?

Sales is a table of 500k rows by the way.

`P1 Sales* = CALCULATE([Sales];filter(DATESBETWEEN(DateTable[Datum];[P1 start];[P1 end]);day(DateTable[Datum])=1))`

or:

`P1 Sales* = CALCULATE([Sales];DATESBETWEEN(DateTable[Datum];[P1 start];[P1 end]);day(DateTable[Datum])=1)`

So this way i pass as filter to CALCULATE only 12 days, namely the 1st day of every month.

Would this speed matters up? Or is this hypothetical BS and do i just creat more overhead? 😛

1 ACCEPTED SOLUTION
Microsoft Employee

@denpries,

In your original post, the P1 Sales* will be more efficient than P1 Sales, and it executes faster than P1 Sales. The DAX Greg_Deckler provides will spend more time to execute comparing with your original measures.

You can use SQL Server Profiler to check the query duration and DAX query plan for these measures and verify the whole process. There are some blogs for your reference.
https://insightsquest.com/2017/05/07/profiler-trace-for-power-bi-desktop/

Regards,
Lydia

Community Support Team _ Lydia Zhang
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.
5 REPLIES 5
Super User

Perhaps:

```P1 Sales =
VAR tmpDates = FILTER(FILTER(DateTable,DAY([Dates])=1),[Dates]>=[P1 start] && [Dates]<=[P1 end)
RETURN SUMX(tmpDates,[Sales])```

Become an expert!: Enterprise DNA
External Tools: MSHGQM
Latest book!:
Power BI Cookbook Third Edition (Color)

DAX is easy, CALCULATE makes DAX hard...
Resolver I

@Greg_Deckler that also works, yes. If i understand it correctly you filter from the dates table all applicable rows (so basically 1 per month) and then sumx evaluates the [sales] for every row of that table and adds it together.

What i dont understand yet, and try to know why, if this approach is more efficient then the other.

Resolver I

Microsoft Employee

@denpries,

In your original post, the P1 Sales* will be more efficient than P1 Sales, and it executes faster than P1 Sales. The DAX Greg_Deckler provides will spend more time to execute comparing with your original measures.

You can use SQL Server Profiler to check the query duration and DAX query plan for these measures and verify the whole process. There are some blogs for your reference.
https://insightsquest.com/2017/05/07/profiler-trace-for-power-bi-desktop/

Regards,
Lydia

Community Support Team _ Lydia Zhang
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.
Resolver I

Announcements

#### Europe’s largest Microsoft Fabric Community Conference

Join the community in Stockholm for expert Microsoft Fabric learning including a very exciting keynote from Arun Ulag, Corporate Vice President, Azure Data.

#### Power BI Monthly Update - August 2024

Check out the August 2024 Power BI update to learn about new features.

#### Microsoft Fabric & AI Learning Hackathon

Learn from experts, get hands-on experience, and win awesome prizes.

#### Fabric Community Update - September 2024

Find out what's new and trending in the Fabric Community.

Top Solution Authors
Top Kudoed Authors