Is it possible to perform spatial join in PostGIS and keep all features?

Question

I am attempting to create an employment change map using a hex grid. I have individual establishment data as points with attached employment figures. When I ran the spatial join using the postGIS extension in QGIS 2.6 it returns all of the hexes where the join is true, as expected. But for cartographic sake I would like the whole net return where I could symbolize the null cells myself and not just have them drop out.

Is there a way to do this through postGIS similar to the return all features option in ArcMap's spatial join? My sample code right now.

--view joining employment data to hexagon grid
   CREATE VIEW food_employment_2yr_hex AS
SELECT a.gid AS gid, sum(b.avgemp) AS Emp_2010, sum(c.avgemp) AS Emp_2012,   a.geom AS geom
    FROM hex_grid_pdx_nad83 a, qcew_2010_nad83 b, 
    qcew_2012_nad83 c
    WHERE ST_Within(b.geom, a.geom) AND ST_Within(c.geom,a.geom)
    GROUP BY a.gid;