How to save a virtual layer (from a filtered join) with features from original layer in QGIS?

Question

To be specific, I have a shapefile on census block groups (CBGs) in Georgia, but I only want to use those in Atlanta's commuting zone (CZ).

However, commuting zone is not a field in the census shapefile, so I join the layer with a different table that links CBG IDs to CZs. If I want to filter this layer, I am prompted to define a virtual layer, which I duly do.

Yet when I save that virtual layer (showing all the original fields, and CZ, and only for CZ=141, which is Atlanta) the shapefile is empty, thus the geography is lost somewhere along the line.

What is the proper way to do this?

I am on QGIS 2.18.2.

Answer 1

Instead of filtering the layer, make a Select By Attributes query, and when you go save it, mark the box that reads "Save only selected features".