QGIS: Becoming a GIS Power User

Using the QspatiaLite plugin

Sometimes, you may not need to load a whole layer into QGIS, but only some subset of it, or perform some calculations on the fly. In such situations, the ability to run complex SQL queries and display their results in QGIS will be very useful.

This recipe shows you how to execute SQL code with the QspatiaLite plugin and load data in QGIS.

Getting ready

To follow this recipe, you need to create connection to the cookbook.db database created in the Loading vector layers into SpatiaLite recipe in Chapter 1, Data Input and Output. Alternatively, you can use your own SpatiaLite database, but be aware that you might have to alter some of the following SQL statements to match your tables.

Additionally, install the QspatiaLite ...