Tips, Tricks, and Advice from the SQL Server Query Optimization Team

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...

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...

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...