Merge

  • Comments posted to this topic are about the item Merge



    Ole Kristian Velstadbråten Bangås - Virinco - Facebook - Twitter

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  • Nice question Kristian! Thanks 🙂

    ~ Lokesh Vij


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  • Great question, thanks!

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  • Good question. I learn something new !!!

    Thanks

    Thanks
    Vinay Kumar
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  • Nice question, thanks

  • Nice question on merge!

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  • Thank you for the question and lesson.

  • Thanks for the question, Ole. Interesting.. (before I knew very little about the merge, but know even little bit more... 🙂 )

    ww; Raghu
    --
    The first and the hardest SQL statement I have wrote- "select * from customers" - and I was happy and felt smart.

  • Good question, learned something I didn't know about Merge and I use it not every day, but at least every other week. 🙂



    --Mark Tassin
    MCITP - SQL Server DBA
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  • Ugh, apparently I really need to use MERGE more often.

    Thanks for the great question!

  • What's Merge got to do with Valentine's Day?? 😉 Just kidding, good question!

  • Great question... learnt something new today..! Thanks for the qotd

    ___________________________________________________________________
    If I can answer a question then anyone can answer it..trying to reverse the logic.. :hehe:

  • Nice question. However, the explanation would have been better if it had pointed out that filters like this can be placed in the when matche/not matched conditions. In this merge statement the when clause should have been when not matched by target and src.RowNo = 1 if the intention was to get only the three rows with RowNo 1.

    In fact even filtering of the target table in the on clause other than with a matching codition between source and target is stated by MS to be bad practice, as it can lead to unexpected results (ie it doesn't necessarily do what you would expect it to do).

    BoL


    It is important to specify only the columns from the target table that are used for matching purposes. That is, specify columns from the target table that are compared to the corresponding column of the source table.

    Tom

  • Terrific and subtle point. You got me. Any "filtering" must be done in the WHEN [NOT] MATCHED AND xxx clause.

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