Forum Discussion
TIP::COPY DATA::SOURCE::TSQL QUERY::LIMITATION
Hello Element115 ,
Thank you for your update and for clarifying your progress.
You’re absolutely right in this case, PARTITION BY NULL isn’t strictly necessary. I included it to intentionally ensure ROW_NUMBER() treats the whole dataset as one partition, keeping the ID sequence continuous. It’s something we often do as a best practice to make the partitioning behavior clear.That said, leaving it out gives you the same result since the query defaults to one partition anyway. So, feel free to skip it, it won’t affect how the query runs.
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Hello Element115 ,
The ROW_NUMBER() function generates unique row numbers, and PARTITION BY groups the data into sections where numbering restarts. To partition by year and month, you should write PARTITION BY YEAR(vis.[DATE]), MONTH(vis.[DATE]) . This creates a new row number sequence for each year-month combination. The ORDER BY vis.[DATE] DESC ensures the latest dates get the first numbers
If this post helps, then please give us Kudos and consider Accept it as a solution to help the other members find it more quickly.
Thank you.
Anonymous Thanks. I do have a follow-up question though. What happens if the lakehouse data sink is partitioned by YEAR, or by YEAR and MONTH?
Do we just change the window function call like so?
ROW_NUMBER() OVER (PARTITION BY YEAR(VIS.[DATE]) AND MONTH(vis.[date]) ORDER BY vis.[DATE] DESC)Hello Element115 ,
The ROW_NUMBER() function generates unique row numbers, and PARTITION BY groups the data into sections where numbering restarts. To partition by year and month, you should write PARTITION BY YEAR(vis.[DATE]), MONTH(vis.[DATE]) . This creates a new row number sequence for each year-month combination. The ORDER BY vis.[DATE] DESC ensures the latest dates get the first numbers
If this post helps, then please give us Kudos and consider Accept it as a solution to help the other members find it more quickly.
Thank you.