A cache-conscious MapReduce star join algorithm was presented. each column of fact table was separately stored. and dimension table was divided into several column families according to dimension hierarchy. Fact table foreign key column and corresponding dimension table was co-location storage. https://www.roneverhart.com/MagnaFlow-2000-Dodge-Dakota-California-Grade-CARB-Compliant-Direct-Fit-Catalytic-Converter/