Lesson Learned #498:Understanding the Role of STATMAN in SQL Server and Its Resource Consumption
Today, I worked on a service request that our customer reported a performance issue and they reported that this query: SELECT StatMan([SC0], [LC0], [SB0000]) FROM (SELECT TOP 100 PERCENT [SC0], [LC0], step_direction([SC0]) over (order by NULL) AS [SB0000] FROM ..] TABLESAMPLE SYSTEM (@samplePercent PERCENT) WITH (READUNCOMMITTED) ) AS _MS_UPDSTATS_TBL_HELPER ORDER BY [SC0], [SB0000] ) AS _MS_UPDSTATS_TBL OPTION (MAXDOP 16, RECOMPILE). I would like to share my lessons learned here.
