Collecting Statistics
Statistics about tables, columns and indexes are a critical component in producing good query plans. This session will examine the differences between random AMP sampling, full statistics collection, and USING SAMPLE collection, and will share details about how each of these 3 approaches works internally. Statistics histograms, their uses and limitations, will be explored. You'll get some insights into collecting statistics on multiple columns, on indexes, on and on the system-derived column PARTITION. Statistics extrapolation will be touched on briefly, and the session will wrap up with some general recommendations for collection statistics.
Training by
DebraH
01 Apr 2011