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_Emil_'s avatar
_Emil_
Advocate II
9 years ago

Getting Random Duplicates after Merge and Expand

I'm using Merge (left outer) on two fields with Expand column, my right side is unique (Check with SQL including case sensitive collation).   Before I expand I don't get duplicates, after I expand ...
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v-huizhn-msft's avatar
v-huizhn-msft
Microsoft Employee
9 years ago

Hi _Emil_,

The date in left side have duplicate, right? If it is, I try to reproduce the scenario, please review the following.

The first table is left side table, the second is right side table which is unique.



I merge(left outer) on two tickets, and result as the screenshot below.



From the result, I get duplicates after expand. This is because there are duplicates, the value in right site must matches them.

If you have any other issue, please feel free to ask.


Best Regards,
Angelia

  • _Emil_'s avatar
    _Emil_
    Advocate II
    9 years ago

    Hi Angelia,

     

    Let me clarify, using your example you have 5 rows on left side, and you get 5 rows as final result, in my case I get 5+ rows, even when right side is unique.

     

    So my output is like this:

    1. D, D

    2. D, D

    3. C, C

    4. E, E

    5. E, E <-- duplicated

    6. F, NULL

     

    and if I refresh data my duplication would be different like this:

    1. D, D

    2. D, D

    3. C, C

    4. C, C <-- duplicated

    5. E, E 

    6. F, NULL

     

    I have this beheviour on several different merges now, in all cases right side is unique, so I don't expect to get more rows on left side, but I do. 

     

     

    If I take my duplicated row and filter my left side (1 unique row) than I no longer get the duplication, and if I was doing something wrong (which is possible) I would expect it to be there duplicated.

     

    I'll try to play with it a bit more to see if I can narrow down the issue.

     

    Regards

    Emil

    • v-huizhn-msft's avatar
      v-huizhn-msft
      Microsoft Employee
      9 years ago

      Hi _Emil_，

      For your requriement, it should change dynamically. We are unable to achieve your expected result. Thanks for your understanding.

       

      Best Regards,
      Angelia

      • _Emil_'s avatar
        _Emil_
        Advocate II
        9 years ago

        Thanks, it seems to happen only with larger volume of data, and affects only very small % of rows, but appears with almost every merge I use that uses different logic, columns (no issues with SQL Left join).

         

        I'll try to narrow it down and see if it is something on my side that I'm misunderstanding. 

         

        Regards

        Emil