QGIS – Creating New Layer from Selection

qgisquery-layerselect-by-attributeselect-by-location

Is it possible to create layers from selection in QGIS? I am using QGIS 1.7.4-Wroclaw.

To make it easier for others to see this, here are some pics. I used QGIS 2.0.1-Dufour.

Selecting
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Saving
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Adding
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Best Answer

After making a selection in a layer, right click on it and choose save selection as.

Update for QGIS 3.2 Bonn as of 2018

As this is the accepted answer and the way of doing this has evolved somewhat, beginners might find this answer incomplete, so:

After making a selection in a layer, right click on it and choose "Export" > "Save Selected Feature As..."

which is actually just a nice redundancy, because it takes you to the same mask as clicking "Save Feature As...", but it already checks the box "Save only selected features"

Related Solutions

[GIS] Show alternating contour lines

If you have a contour lines layer with associated elevation attribute, you can query the contour lines in reference to the elevation values. More in detail, you could define a rule-based style in Vector properties --> Style in order to query the elevation values you are interested in.

For instance, suppose you have contour lines with equidistance 5 m and you want to show only contour lines with equidistance 10 m. A possible query in a rule-based style could be:

"elev" % 10 = 0

Only the contour lines which match this expression (elev value which ends with 0) will be filtered and consequently shown. Instead, contour lines with elev value which ends with 5 will be hidden (but they are always there).

QGIS – How to Select Features Intersecting Another Layer’s Selection

VirtualLayers possibly to the first world problem rescue; this is a nice solution if you can express your polygon selection with some condition (I use an id <some_id> as an example here):

Layer -> Add Layer -> Add/Edit Virtual Layer...
Import -> both your WFS layers when loaded
(you can try adding the service directly via Add -> select WFS as provider and paste in the URL, but it keeps on throwing errors for me on QGIS 2.18)

and then type

SELECT pts.*
FROM <point_layer> AS pts,
     <polygon_layer> AS plg
WHERE plg.<id_column> = <some_id>
  AND ST_Intersects(pts.geometry, plg.geometry);

into the Query field.

If you want to manually select features:

Edit -> Copy Features
Edit -> Past Features As -> Temporary Scratch Layer...

and continue with your usual workflow from there
(you could of course use that layer in the above query to get the intersecting points into a virtual layer; just omit plg.<id_column> = <some_id> AND in above query and replace <polygon_layer> with the name of the scratch layer).

Best Answer

Update for QGIS 3.2 Bonn as of 2018

Related Solutions

[GIS] Show alternating contour lines

QGIS – How to Select Features Intersecting Another Layer’s Selection

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