D2 and D4 are materialized (join) views. D3 and D5
are added for completeness since we don’t use them in any
of the seven queries. They are included so that we can
answer arbitrary queries on this schema as is true for the
product schemas.
On the commercial row-store DBMS, we used the
common relational schema given above with a collection
of system-specific tuning parameters. We also used
system-specific tuning parameters for the commercial
column-store DBMS. Although we believe we chose
good values for the commercial systems, obviously, we
cannot guarantee they are optimal.
The following table indicates the performance that we
observed. All measurements are in seconds and are taken
on a dedicated machine.