In general the "best" algorithm seems dependent on specific usage patterns. A different angle is to study or sample actual usage patterns and automatically adju

In general the "best" algorithm seems dependent on specific usage patterns. A different angle is to study or sample actual usage patterns and automatically adjust the structure/algorithm based on that. The indexes can be readjusted during off/slow hours. (If you don't have off hours, then such a system may not be the best fit.)