QGIS Virtual Layers: mix them all data!

Abstract

A new feature landed recently in QGIS : Virtual layers. Virtual Layers are database views over existing QGIS (vector) layers. These layers can be built by the use of the powerful SQL language and then allow for advanced uses in a consistent manner : joins between different layers, including spatial joins, subset selection, type conversion, on-the-fly attribute and geometry generation, etc. The following operations are now supported in QGIS : you can create a new virtual layer through the “New layer” menu; you can open a saved virtual layer through the “Add layer” menu; a virtual layer can be created out of a layer selection by right click in the context menu; If you want to filter a layer that has “joins”, it will propose to copy it to a virtual layer and In DBManager, there is a new entry “virtual layers” where you can use an SQL query to setup a virtual layer. This presentation will explain the concepts and show the current available features provided by this implementation