merge queries vs merge queries as new

[bbbt123]

Hello,

I have 2 databases, both with 1.5 millions rows. I have merged them as new table and I have disabled "enable load" in the two original tables. if I had merged them without creating a new one, would my database be "lighter"? or having disabled the load in the original tables will make the overall file lighter anyway?

Thank you in advance

[zoloturu · Accepted solution]

Hi @bbbt123 ,

You think right - disable load of two source tables will make file lighter. There is another option which can provide similar or even a little bit better result. The logic is to put all code to one query. 

In more details. Go to your new query which is a merge of two other. Let's name them Table1 and Table2. Both secondary queries have some PowerQuery code behind, move it to the main query as below:

let
   Table1 = let ... in ... ,
   
   Table2 = let ... in ... ,
   
   Result = Table.Combine({Table1, Table2})
in
   Result

Regards,
Ruslan Zolotukhin (zoloturu)
BI Engineer at Akvelon Inc. / Kharkiv Power BI User Group Leader / DAX & Power BI Trainer
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[PBILover]

HI @bbbt123 , @Adamtall ,  @zoloturu

I have similar situation. @bbbt123  which approach did you you use? 

[Adamtall]

Hi,

The refresh need to check both tables, so the load will take the same time.

but when it have refreshed the PBI file will only save the rows from the one table that have "enable load".

So the file will be lighter with disabled "enable load" on the orginal tables.

But if you merge with one of the 2 tables and disabled "enable load" on the not merged table it will be same as above.

But I think its more clean to have groups Extract/Transform/Load stages in the datamodel. 

So the extract has only raw data and in transform in this case has the merge "as a new table".

This will help others too understand the datamodel faster and work on the same model.

/Adam