Table Merge of Many to one results to multiplied rows

[marbinv3]

Hi Experts,

I am trying to Merge 2 tables with a Many to One relationship.

This is the Many Table (338,427 rows):

While this is the one table (2468 rows [no duplicates for the ID]): 

When merging the tables using Left Outer, it give a complete match based on PowerBI estimates but rows are multiplied to 5.4 million rows. I am using the "Many" table as main table. Can anyone please help me?

[parry2k]

@marbinv3 that makes sense. Glad you figured it out. It is very hard to reply to such posts without looking at the data. Good luck!

[marbinv3 · Accepted solution]

This has been resolved. 

The first table was a result of an SQL query which was also a joint table. The merge with the secondary table was connecting to the mediating table resulting to multiplication of rows. Thanks!

[parry2k]

@marbinv3 if I understood your question correctly, you are doing merge in power query and if you are doing merge on correct columns I don't expect the number of rows to increase. Surely missing something here. Can you share pbix file with sample data, remove sensitive information before sharing. 

[lbendlin]

Help with what?  You are asking for a cartesian product (left join, no less) so that's what you are getting. 

If you want a smaller result then use less data, or aggregate / filter earlier.

Or - don't do the merge in Power Query, instead load both tables and connect them in the Vertipaq data model