I'm using QGIS 3.10.2 A Coruna. I translated a dwg/Pdf Plan into GIS where I harmonized every object in regard to topology and correct geometry. The map represents a development plan of a project we are working on. In this development plan we have different categories: buildings, streets, park area/open space, estates. At first, I had a seperate layer for each categorie, until I realized that everytime a change is made in the plan, It is important to check all the other layers and make sure, that topology is still intact. I found this to be a hassle. So, I decided to put all categories in one layer, that way any changes that occur, will only effect one and one layer only. However, I have a lot of attributes that need to be implemented in the layer, the problem ist, that some attributes only apply to some categories and not others, and some attributes apply to all categories. For example: The attribute "Name" applies to all categories, but the attribute "use" is only for buildings, where I have predifined values. My attribute table to growing rapidly and my capacity of keeping track of which attribute is set for which category is decreasing. For my collegues I often have to export only one category, and if I always manually delete unecessary attributes, mistakes are bound to happen. My question: Is there a possibility in QGIS to only show/export the relevant attribute without me having to do so manually every time I want to look at my data?

I have also considered trying out a database-solution like Postgis, but I'm new to this, so I'm not really sure how I would organise it there either.

I'm using QGIS 3.10.2 A Coruna.

I translated a DWG/PDF Plan into GIS where I harmonized every object in regard to topology and correct geometry. The map represents a development plan of a project we are working on. In this development plan we have different categories: buildings, streets, park area/open space, estates.

At first, I had a seperate layer for each categorie, until I realized that everytime a change is made in the plan, It is important to check all the other layers and make sure, that topology is still intact. I found this to be a hassle. So, I decided to put all categories in one layer, that way any changes that occur, will only effect one and one layer only.

However, I have a lot of attributes that need to be implemented in the layer, the problem ist, that some attributes only apply to some categories and not others, and some attributes apply to all categories. For example: The attribute "Name" applies to all categories, but the attribute "use" is only for buildings, where I have predifined values.

My attribute table to growing rapidly and my capacity of keeping track of which attribute is set for which category is decreasing. For my collegues I often have to export only one category, and if I always manually delete unecessary attributes, mistakes are bound to happen. 

Is there a possibility in QGIS to only show/export the relevant attribute without me having to do so manually every time I want to look at my data?

I have also considered trying out a database-solution like PostGIS, but I'm new to this, so I'm not really sure how I would organise it there either.