QGIS adding or removing values in the style tab (layer properties)

Question

I'm new to QGIS and have recently been testing the software as my org plan to migrate from ArcGIS to QGIS in the near future. I often use the 'Add values', 'Remove values' and the group values feature in ArcGIS (Symobology¬ Categories¬ Unique Values) to display Symbology for selected values. Is it possible to do this in QGIS? With categorized selected in the style menu the only options I can see is to add or delete. Any assistance would be greatly appreciated!

Thanks

Answer 1

It is not quite as straight-forward as in ArcGIS to group values. The symbology rules actually have options that are more powerful than ArcGIS, as you can have Rule-Based Symbology.

In the Layer Properties window, on the Style tab, change the pull-down from Categorized, to Rule-Based. That will change the window to show different classes with Rules and Labels.

Once in this window, you can add different Rule Classes with the "Add Button"

This window lets you define the Label for the Class, and then enter the filter, which is essentially an SQL query on your layer. click the "..." button to bring up the query builder.

Define your filters here, querying the values you want based on one or multiple attributes.

As I said, it is not as simple as selecting classes in ArcGIS and grouping them together, but I think it is ultimately more powerful.