July 2006 - Posts

• UPDATE STATISTICS undocumented options

  If you read the Books Online page describing the UPDATE STATISTICS command, you will see that there are some undocumented options. UPDATE STATISTICS table | view [ { { index | statistics_name } | ( { index |statistics_name } [ ,...n ] ) } ] [ WITH [ [ Read More... Posted Friday, July 21, 2006 4:08 PM by QueryOptTeam | 9 Comments

• Hints for DML queries

  Not everyone knows that query level hints (like loop join) will impact the entirety of a DML query plan. This includes foreign key validation and indexed view maintenance. Let us look at an example with two tables involved in a foreign key constraint. Read More... Posted Friday, July 14, 2006 4:30 PM by QueryOptTeam | 3 Comments

• Non updating updates

  A question we are frequently asked is what happens when an update statement assigns a column to its same current value. For example, use tempdb go create table t(i int, cc as i + 1) create index t_cc on t(cc) go insert into t values(1) go update t set Read More... Posted Friday, July 07, 2006 2:45 PM by QueryOptTeam | 5 Comments Attachment(s): Profiles.png