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I am using QGIS 3.6.

I'm trying to create a map which labels each parcel according to it's position along the red line, from West to East. I've tried creating a column which uses each features position within the attribute table to do this, however as you can see in the picture, they are not in any sensible order. I normally do this manually, however I have over 3000+ features to edit in that case, it would be good to find an automated solution.

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This answer will number parcels from West to East.

You can create a new layer with the ordered ID

Go the the menu layer / add layer / add-edit virtual layer and enter the following query.

select *, ROW_NUMBER() OVER(ORDER BY ST_MinX(geometry) asc, ST_MinY(geometry) asc) as newID
FROM myLayer

you can replace the layer name (myLayer) with the true name.

The query gets all rows from myLayer then orders each polygon by X and Y and generates a new sequential row number.

To number East to West, you would use st_maxX (to get the eastern most coordinate of each polygon) and you would order the coordinates in descending order (ORDER BY ST_MaxX(geometry) desc, ST_MinY(geometry) asc).

  • This example unfortunately does not work for me in QGIS 3.8.1. And unfortunately I'm too stupid to debug the even more stupid sql-error output: 1 - near "(": syntax error – Bernd V. Sep 14 at 15:04
  • @BerndV. Please provide the complete query you have used. It could be a missing coma or parentheses. If the reported error location doesn't make sense, the trick is to look at the previous statement in the query. PS: don't be too hard on yourself.... not knowing doesn't mean being stupid - else schools would be FULL of stupids – JGH Sep 14 at 15:53
  • I simply copy/pasted the example above. I even renamed my layer to myLayer like in the example. So try yourself with a copy your own code ;) – Bernd V. Sep 14 at 16:21

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