QGIS Tips and Tricks: How to Filter or Display Certain Features
On QGIS Composer how to filter the atlas coverage layer using a project variable (rather than just a value)? - Geographic Information Systems Stack Exchange
Expressions
Attribute table in QGIS – MkrGeo
Attribute table in QGIS – MkrGeo
QGIS 3.2: Drive Down Lists aka Value Relation Widget - North River Geographic Systems Inc