Note: spatial selection only works with database layers, not with files. If you want perform spatial queries please import the files into the database first. Also, make sure that multigeometry type is exploded into the geometry.

Spatial selection allows you to create database queries for layers that reside in the database. This tool allows you to select any database feature from any database layer in your Map View.

You can select features by attributes or by location depending on what do you need.

Basic spatial selection is performed in the following way (use the pictures above and below for reference):

  1. Click the Feature tab.
  2. Select Spatial Selection.

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Example 1. Select polygons that have id attribute less then 1800:

  1. Select table from the dropdown list.
  2. spatial3

  3. Select column from the dropdown list.
  4. spatial5

  5. Write condition “i.e. <1800".
  6. Click Select.
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  8. Click Clear selection.

Example 2. Select lines within the polygons:

  1. Click ST_Within() or write it into the Condition bar.
  2. spatial21

  3. Select line layer and geometry column (wkb_geometry).
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  5. Click “+” button to add another table.
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  7. Select polygon layer and geometry column (wkb_geometry).
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  9. Click Select button.
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  11. Click Clear selection.

Click here to see more examples.