I am attempting to do a join in QGIS between a SQL Server Spatial table and a non-spatial table (on a single integer field). I was able to add both successfully and make the join, but the query builder dialog only shows the fields from the spatial table.
I also tried setting a feature filter on the non-spatial table before joining to the spatial table, but that filter was not honored (no error, but no affect on the layer).
QGIS version: 2.12.1-Lyon QGIS code revision: 16760fd
Microsoft SQL Server 2012 - 11.0.2100.60 (X64)
Feb 10 2012 19:39:15
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Enterprise Edition (64-bit) on Windows NT 6.1 <X64> (Build 7601: Service Pack 1) (Hypervisor)