Hi Suresh

Very interesting article, thank you. I wanted to clarify one point though. You talk about query performance improvement which, of course, is the holy grail with database applications, especially when performance starts slowing down with increased data volumes etc. However, you are also looking at table space optimisation and it appears to me that your article demonstrates the space saving more than performance optimisation.

I realise that you say query performance is improved due to faster joins with higher row density, but you don't show any evidence of that and your simple row count query took longer due to compression. So for optimum query performance would you recommend trying to achieve higher density without compression (by optimising datatypes etc.)?

Best wishes

John