Attribute data quality is important. Setting ranges or value maps greatly helps in preventing errors. For years now you can set these with Attributes Form settings in QGIS. This is a style setting and is only applicable if you have hat style applied to your data layer in QGIS or saved in a QGIS project.
When you collaborate with others on the dataset and someone else is editing the data without using the same style or project, you might get data quality issues.
For GeoPackages a new feature called Field Domains has become available. This allows you to create a Range or Coded Value list on the database level and apply this to fields in any vectorlayer within the GeoPackage. This means you can collaborate on editing data without the use of layer styling or a project and still have the benefits of a more robust way of editing values.
Implementation of the GeoPackage Field Domain feature in QGIS is still in development.

In this talk I will go in to some pro’s and con’s of both methods, needed improvements and I explore some possible future use cases for Field Domains that are not (yet) implemented in GeoPackages and in QGIS.