In case of layers with UUID data type (database Postgresql) when you edit a feature, for example moving a point without edit any attribute, when you save the edits, the content of the UUID field is set to NULL (even if you do not change that specific attribute)
In case of layers with UUID data type (database Postgresql) when you edit a feature, for example moving a point without edit any attribute, when you save the edits, the content of the UUID field is set to NULL (even if you do not change that specific attribute)