I may be missing something obvious here, but I cannot figure it out. In my attribute table under the area_ft_su column, I have a bunch of NULL entries. I want to change those NULL entries to zero without having to manually change each one. The output preview looks correct, but when I click "Ok", nothing happens. Nothing is updated. Am I missing something or is my syntax wrong?

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  • 4
    You can't check whether a value is NULL using =. <something> = NULL will always return NULL, which is interpreted as FALSE in your WHEN statement. Replace WHEN "area_ft_su" = NULL with WHEN "area_ft_su" IS NULL, and it should work
    – Jake
    Commented Oct 29, 2020 at 20:36
  • @Jake Thank you, that is what I was looking for!
    – Binx
    Commented Nov 3, 2020 at 23:18

1 Answer 1


Sort your column of data. Select all the null values by starting at the first null value row and click the left most area, then scroll to the bottom of the table, use shift-select to select all the rows with null values. Use update an existing field and select area_ft_su. Add the "area_ft_su" = 0 as a field to the expression. Hit OK. Save your edits.

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