Working implementation of shared scans capable of supporting both single-table scan, and synchronized multi-table scans. Demonstration involves:

1. run simultaneously 5 full-table-scan queries on Object table and demonstrate they all complete in approx the time it takes to do a single pass through the table.
2. run simultaneously 5 full-table-join queries (Object joined with Source) and demonstrate they all complete in approx the time it takes to do a single pass through the Source table plus the Object table.

Scale: 10% of DR1.

Details of shared scans can be found in §8.10 of LDM-135.