[Qgis-user] Running intersection with PostGIS overlay layer without local recreation of index?

[chris hermansen]

Johannes and list.


On Wed, Apr 16, 2025, 07:35 Johannes Kröger (WhereGroup) via QGIS-User <
qgis-user at lists.osgeo.org> wrote:

> Workaround, that works well in my specific data and use case:
>
> My input layer only covers small and local parts of the full coverage of
> the big PostGIS layer. Because of this I could switch the overlay input
> for the intersection from the PostGIS layer to a query layer that
> filters the PostGIS layer against the convex hull of the input layer
> with ST_Intersects. Now only a small fraction of the features will be
> fetched and the complexity depends mostly on the spatial distribution of
> the input data, not the overlay layer.
>
> Works very well so far and vastly faster.
>
> I still feel like I am overlooking something very basic though :o)
>

A question  - did you try both layers in PostGIS?

>
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