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Anonymous
Not applicable

Aggregating a table in Power Query

I have a table that has over 15 million records. When I use Group by feature or do List.Sum function, it takes forever to calculate it. Doing the same in Dataflow just crashes it.

What would be the most effecient way of summing a column in this table or counting rows in the table without using list.sum or related functions?

 

Thanks

3 REPLIES 3
Anonymous
Not applicable

Could we take a peek at your code, and maybe some sample data please?

Anonymous
Not applicable

List.Sum is pretty straightforward, what do these 15M rows look like, and what is the source?

Anonymous
Not applicable

source is sql. 

There's only 4-5 columns. 3 descriptive, 1 date and 1 $ amount. 

I've tried group by in data flow and it takes a lot of time and then it crashes.

on the desktop it takes half hour just to do sum or distinct count of rows.

List.Sum seems straightforward but not sure why it would be such a resource constraint. 

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