Merge queries using left outer (higher number of rows in first table)

[Turquesa]

Help needed! I hava merged two tables using the left outer option and expand (I am unable to use fuzzy match as some columns contain numbers). For some reason I have a higher number of rows in the combined table after performing this merge which leads me to believe that some rows have been duplicated. Any help/thoughts will be highly appreciated!

Thanks in advance!

[v-yilong-msft · Accepted solution]

Hi @Turquesa ,

First of all, I Think you need to ensure that the columns you are using as keys for the merge operation are unique, at least in the left table. 

Also you can manually inspect or use queries to identify if there are multiple matches in the right table for rows in the left table.

Secondly I think you can consider removing duplicate rows from the right table before performing the merge operation. This can be done using the Power Query Editor by selecting the Remove Duplicates option under the Home tab. Maybe this document can help you: Tutorial: Shape and combine data in Power BI Desktop - Power BI | Microsoft Learn

Best Regards

Yilong Zhou

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