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I know how to get the geometry (x,y) into attribute fields with the calculator, but I can't figure out how to update the geometry from values contained in attributes.

I am trying Field Calculator > Update existing field > , but I can't find how to assign my "x" and "y" fields to the actual feature geometry.

I don't want to manually drag each point with the vertex editor, or type in each coordinate. I have to update many points.

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Assuming you have chosen <geometry> field in the Update existing field drop down list, the expression you need would be:

geom_from_wkt('POINT('||"x"||' '||"y"||')')
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  • Awesome - I would never have figured out the || by myself... Thank you for the quick response. – Benoit_W Jun 8 '18 at 4:28
  • Great! Thanks @Benoit_W :) You would have found out that sooner or later. – Kazuhito Jun 8 '18 at 12:48
  • The syntax is actually quite misleading. Here is the correct one with example coordinates: geom_from_wkt('POINT('||'31.797788'||' '||'30.729471'||')') Notice the single quotes. Using double quotes in QGIS 2/3 will cause an error as it mistakens the x and y values as field names. – 15Step Jan 24 '19 at 12:50
  • @15Step This syntax is reading values from "x" and "y" fields, such field names were set by OP. – Kazuhito Jan 24 '19 at 13:17
  • I misunderstood the question, sorry about that! I think the comment could still be useful for updating numerical coordinates in the <geometry> field. – 15Step Jan 24 '19 at 14:24

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