cancel
Showing results for 
Search instead for 
Did you mean: 

Fabric is Generally Available. Browse Fabric Presentations. Work towards your Fabric certification with the Cloud Skills Challenge.

Reply
Anonymous
Not applicable

Referenced table or GROUPBY table

Hi all,

 

I have a scenerio whereby I have a Master table (MasterCodes) with a list of codes organised by Identifier TYPE (Catalogue/SubCat/Format etc). Currently I split this table into 10 individual tables, referencing the Master table, to create a table for each Identifier.

e.g.

let
Query = MasterCodes,
TYPE = Table.SelectRows(Query, each ([Identifier] = "SubCat"))
in
TYPE

 

My model is getting quite large and PBI takes ages to respond, so I'm trying different ways to improve.

 

Is the above method the best way, or should I create a dax table with GROUPBY? What performance benefits would I get from either?

e.g.

Table_SubCat = FILTER(GROUPBY(MasterCodes, MasterCodes[Identifier], MasterCodes[Code], MasterCodes[Description]), MasterCodes[Identifier] = "SubCat")
Table_Format = FILTER(GROUPBY(MasterCodes, MasterCodes[Identifier], MasterCodes[Code], MasterCodes[Description]), MasterCodes[Identifier] = "Format")
 
The splitting of the tables is required for references.
I have a table called Panel, which has various fields relating to different Codes, (Catalogue, SubCat, Format etc). Since I can't have a filter on a relationship in the model I need to have them in different tables.
 
Screenshot_5.png
 
The original SQL would have looked like this:
 
from Panels p
left outer join MasterCodes ms1 on ms1.Code = p.FormatCode and ms1.Identifier= 'Format'
left outer join MasterCodes ms2 on ms2.Code = p.SubCatCode and ms2.Identifier= 'SubCat'
 
 
 
4 REPLIES 4
v-yingjl
Community Support
Community Support

Hi @Anonymous ,

If you've fixed the issue on your own please kindly share your solution. If the above posts help, please kindly mark it as a solution to help others find it more quickly. Thanks!


Best Regards,
Yingjie Li

v-yingjl
Community Support
Community Support

Hi @Anonymous ,

I prefer you to use Table.selectrows() in power query:

  1. Power query statement cleans the undering data of your model, although it could take a long time if your model is very large, you can get a succinct data table and use it to create another tables and visuals by dax easily.
  2. Dax query statement only process surface data of your model. For example, if your model is very large without any filter, it will fully load into power bi and dax will calculate all of your data based on your model. If you use groupby to create other tables, it could take such a longer time than power query.

In conclusion, if your model is very large, using power query to clean data in advance is better than using dax directly, although both of them can get the same result finally.

 

You can also refer these articles about differences between dax and power query in details:

  1. Do You Know the Differences Between M and DAX in Power BI? 
  2. M or DAX? That is the Question! 

Best Regards,
Yingjie Li

If this post helps then please consider Accept it as the solution to help the other members find it more quickly.

Pragati11
Super User
Super User

Hi @Anonymous ,

 

First thing, why you are creating multiple tables for different TYPE from your master table?

What kind of visualisations you are trying to achieve using these individual tables?

 

Please answer above in order to understand what you are trying to acive in these tables.

 

Thanks,

Pragati

Best Regards,

Pragati Jain


MVP logo


LinkedIn | Twitter | Blog YouTube 

Did I answer your question? Mark my post as a solution! This will help others on the forum!

Appreciate your Kudos!!

Proud to be a Super User!!

Anonymous
Not applicable

I've updated the original post

Helpful resources

Announcements
PBI November 2023 Update Carousel

Power BI Monthly Update - November 2023

Check out the November 2023 Power BI update to learn about new features.

Community News

Fabric Community News unified experience

Read the latest Fabric Community announcements, including updates on Power BI, Synapse, Data Factory and Data Activator.

Dashboard in a day with date

Exclusive opportunity for Women!

Join us for a free, hands-on Microsoft workshop led by women trainers for women where you will learn how to build a Dashboard in a Day!

Power BI Fabric Summit Carousel

The largest Power BI and Fabric virtual conference

130+ sessions, 130+ speakers, Product managers, MVPs, and experts. All about Power BI and Fabric. Attend online or watch the recordings.

Top Solution Authors
Top Kudoed Authors