QGIS Quick Tip - Spatial Query

To do a spatial query to find a certain feature within a distance of another you can use a combination of attribute and spatial selections.

If any distance is involved, your data must be projected!

If you use unprojected data (like WGS-84), your distance must also be in unprojected units (degree). Distance in degrees are not uniform in east-west and north-south, so if you choose this method your buffers will look like ovals and not circles.

If you want to use Imperial measurements, you need to convert it to metric first. However, if you have data with coordinates in feet, yard or miles, that might also work. The given distance assumes the same unit of measurement as the data coordinate system.

You can probably create a modell or tool to do most of these steps for you, but in order to explain all the steps everything is included in the video (even if it moves quickly at times).

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