OK, I still have a way to go in learning about data compression
in SQL Server 2008 but one thing that I do know is that nothing
is free. So, the trade-off will be performance (i.e. CPU) v.
space. And, that’s not really a new trade-off wrt to
compression. Sometimes that trade-off has other benefits that
still minimize the overall cost (for example, backup compression
compresses in-memory and before it goes to disk… this actually
makes the overall backup process faster because the actual
backup written to disk is smaller). However, if we’re talking
about data and data access, then we need to think more about how
the data is going to be used as well as the impact on
performance. I can definitely think of many reasons to compress
older (and read-mostly, if not read-only) data (mostly due to
volume) but depending on the queries and the impact to
uncompress it (based on the volume of data being accessed), I’m
going to do a lot of testing before I compress high
performance/OLTP data. To help estimate the savings on