Paul White (@SQL_kiwi) talks about a regression in the optimizer's handling of aggregates against partitioned tables when moving from SQL Server 2005 to SQL Server 2008+.
Paul White (@SQL_Kiwi) continues his discussion about optimization and how recognizing transformations can help you make better decisions about potential query re-writes.
SentryOne's Aaron Bertrand (@AaronBertrand) discusses a few additional places to get information useful for decisions about creating new indexes that are suggested as "missing" by various tools.
Aaron Bertrand (@AaronBertrand) talks about a subtle way that ad hoc queries can interfere with SQL Server performance by taking up more space in the plan cache than they really need.
Aaron Bertrand (@AaronBertrand) of SQL Sentry discusses a couple of advantages and a hefty list of limitations with filtered indexes in SQL Server 2008 and above, with links to no less than 36 Connect items!
SQLskills' Joe Sack (@josephsack) walks us through an interesting scenario where we might blame a query performance issue on parameter sniffing or bad statistics, when it actually turns out that a check constraint is the best solution to keep the optimizer honest.
Paul White (@SQL_Kiwi) makes some great points about limitations in SQL Server's optimizer, and things you need to watch out for, when it comes to filtered indexes.
Jonathan Kehayias (@SQLPoolBoy) of SQLskills.com evaluates the performance impact of query_post_execution_showplan and explains why you need to be very careful about using it in a production environment.
