The fastest way to create a join between two tables containing a UUID and dates

[Anonymous]

Hello!

I'm looking for the fastest way to to create a join (with M) between two tables containing a UUID and dates

I have a table A containing more than 1M rows

And a table B containing more than 1M rows

With "Table.NestedJoin" it takes a long time.

I  read about a technique with "Table.Join" instead of "Table.NestedJoin" but I can't get it to work.

= Table.NestedJoin(#"step1", {"sharing_flow_id"}, #"table B", {"sharing_flow_id"}, "table B", JoinKind.RightOuter),

Thanks!

[ImkeF · Accepted solution]

Hello @Anonymous ,
the syntax for the Table.Join formula would be this:
Table.Join(#"step1", {"sharing_flow_id"}, #"table B", {"sharing_flow_id"}, JoinKind.RightOuter),

If one of the joining columns has unique values in it, you can speed up the process immensly by creating a KeyColumn like described here: 
Chris Webb's BI Blog: Improving The Performance Of Aggregation After A Merge In Power BI And Excel Power Query/Get&Transform Chris Webb's BI Blog (crossjoin.co.uk)

You can find more performance tips here, btw:
Speed/Performance aspects – The BIccountant

[Anonymous]

Thanks a lot 

I also found this article very interesting!

https://exceleratorbi.com.au/replace-guids-with-a-surrogate-key-for-better-performance/