As discussed in Chapter 31, “Understanding Query Optimization,” SQL Server updates index statistics automatically as data is changed in a table. In some environments, excessive auto-updating of statistics can affect system performance while the statistics are being updated. SQL Profiler can be used to monitor auto-updating of statistics as well as automatic statistics creation.
To monitor auto-updating of statistics, you create a trace and include the
AutoStats event from the
Performance event category. Then you select the
Object ID columns. When the
AutoStats event is captured, the
Integer Data column contains the number of statistics updated for a given table, the