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I am using QGIS 2.14 and am working with two layers: a layer of US Census Blocks and a layer of information on internet providers within each block. The internet provider layer is a CSV flat file, and the census block layer is a shapefile from the US Census TIGER site. I'd like to be able to create a unified layer of internet providers with information on each so I can, say, click "Verizon" and see everywhere Verizon offers service, or select just those blocks where the minimum speeds are in excess of X.
I understand I can't do a simple Join because it only joins one row of the CSV to each census block. I have set up a Relation in the Project Properties, which reflects the data structure I want, but I can't figure out how to make it just display in the map as a new layer.
I also tried creating a new layer by joining the CSV to the census block layer, but QGIS complained it wasn't a valid shapefile.