QGIS » QGIS Application

I used to edit subsets when I was using PostGIS layers. Surprisingly that doesn't work for Shapefiles.

As soon as you place a query on a shapefile, it's capabilities drop from 975 to 704, which raises "Provider cannot be opened for editing".

Creating a query also creates an inconsistency in the UI:

Whilst the editing pen is still blue in the toolbar, it's already greyed out in the attributes table. Clicking the pen in the toolbar raises aforementioned error and stalls it in grey. Removing the query doesn't solve this issue. Opening the attributes table again, the pen is blue there.

So it seems, the toolbar's symbol is not up to date.

975 and 704 equal:

[[PyQt]]4.QtCore.QString(u'Add Features, Delete Features, Change Attribute Values, Add Attributes, Create Spatial Index, Fast Access to Features at ID, Change Geometries')

and  

[[PyQt]]4.QtCore.QString(u'Create Spatial Index, Fast Access to Features at ID')