Update Statistics task has been referenced many times in previous chapters, and now it's time to investigate exactly what it does and how it works. When the
Update Statistics task is run, it executes the
UPDATE STATISTICS command against all of the tables in the databases you select, bringing up to date all index and column statistics.
As discussed in Chapter 7, the
Rebuild Index task automatically updates statistics and so you should not run the
Update Statistics task after running the
Rebuild Index task. To do so would, at best, be a waste of server resources and could, if you choose the incorrect configuration options for the
Update Statistics task, actually degrade the quality of the statistics available ...