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RenataOG30s's avatar
RenataOG30s
Frequent Visitor
4 years ago

Merge queries issue.

Hello folks,

 

Why would a left outer join reduce the number of rows?
 
Thanks in advance.
R
Need Help

4 Replies

  • amitchandak's avatar
    amitchandak
    Super User
    4 years ago

    RenataOG30s , left should not reduce rows. Unless the join column has null/blank value on the left side.

     

    Can you share sample data ?

  • v-easonf-msft's avatar
    v-easonf-msft
    Community Support
    4 years ago

    Hi, RenataOG30s 

    Which table do you compare the result table with, the first table or the second table?

     

    Best Regards,
    Community Support Team _ Eason

    • RenataOG30s's avatar
      RenataOG30s
      Frequent Visitor
      4 years ago

      1st table is my main table, and I want to bring the matches from the second table.

      • v-easonf-msft's avatar
        v-easonf-msft
        Community Support
        4 years ago

        Hi, RenataOG30s 

        It's really weird. When using left outer join, all data in the first table will be retained. 

        Can you show relevant screenshots? Have you checked the missing rows in 1st table？

         

        Best Regards,
        Community Support Team _ Eason