LAG / LEAD function misses the last iteration

Pritesh
Pritesh ⚪️
in Beastmode & Analytics

Hi experts!

I'm using the lead / lag function in beast mode to find out the last row from each group of index rows simply by comparing the value of primary key of next/previous. It works accurately except it misses the last / first group (last when using lead and first when using lag).

Here's my beast mode code:

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And, here's my data table and result of the calculated field...

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If you see it correctly punches '1' for the group Canada, but misses for US. If I use the lag function, it punches value for US but misses for Canada.

One way I could think of is to punch '1' by default for the last row, but I couldn't found the way to use WHEN and identify the last row - if you could help me with that, it would be great.

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Currently, I'm using a sloppy workaround of using both 😋 (see below) - it works but I want to do it much cleaner way.

Current workaround:

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Best Answer

Answers

  • Pritesh
    Pritesh ⚪️

    Also, if there's only one group, then lead/lag doesn't work at all!!

    So, in that case, I just want to punch '1' for the last row. Is there a way to use CASE..WHEN..END to punch a value for the last row? something like...

    CASE

    WHEN CURRENT_ROW() = LAST_ROW() THEN 1

    END

    ==================================================================

    Using MAX & FIXED BY works in general, see below...

    image.png
    image.png


    ... but when I apply filter on that calculated field to show only latest row, it picks the first row with blank version irrespectively. Ideally it should have filtered the row with version "2022-11-08-0014", however, it picks the row with blank version irrespectively. I even tried to sort the versions with descending order but doesn't work...

    image.png


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