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I have a shapefile with more than 180,000 rows. Whenever I want to apply the field calculator (e.g. for $id or $area), QGIS crashes (waiting to respond). My PC has 32GB RAM.

Any idea what I can do?

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    When I faced with this problem I started use SpatiaLite database. There you could make same result in 1-2 minutes. If it interesting I might explain step by step all process.
    – krvrd
    Commented Mar 8, 2018 at 17:43
  • Can you share the file? I suspect there's some corruption here and would like to investigate
    – ndawson
    Commented Mar 8, 2018 at 21:36
  • I would like to but unfortunately I am not allowed to share the file.
    – Stücke
    Commented Mar 9, 2018 at 8:05

4 Answers 4

Reset to default
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Use the field calculator from the main window.

Adding/deleting columns with attribute tables open is super-slow.

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  • Actually to be a bit more precise: close the attribute table while running the calculator on large datasets.
    – Matthias Kuhn
    Commented Mar 9, 2018 at 14:28
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This may well be a matter of patience. I've used the field calculator ($x and $y) on points layers with over 10 million features. Using a 16BG RAM PC, I also get the apparent crash of 'waiting to respond', but it still goes onward, and does provide results after a while (in my case, after a couple of hours).

I've used a SpatiaLite format, which runs much quicker than the CSV format that this data was originally in.

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I came across the correct answer! Don't use the attribute table but rather use the field calculator directly from the main window. Worked well forme! Took only a minute or so. Solved, thanks!

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If you haven't already, I would create a spatial index for the file.

This may help.

enter image description here

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  • I've tried to create a SpatiaLite index but that doesn't change anything. Is there a prefered file format for large field calculations? Should I use QGIS 2.X or QGIS 3.X?
    – Stücke
    Commented Mar 9, 2018 at 8:06
  • This answer walks you through adding a spatial index to your existing shapefile. It's a completely different process from converting your shapefile into a SpatiaLite database.
    – csk
    Commented Mar 9, 2018 at 18:18

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