Tag : optimizer - SentryOne Team Blog

Tag: optimizer

Paul White : UNION ALL Optimization

Paul White : UNION ALL Optimization

Paul White (@SQL_Kiwi) digs into row goals as he explains some interesting and inconsistent behavior with UNION ALL.

Paul White : Cardinality Estimation for a Predicate on a COUNT Expression

Paul White : Cardinality Estimation for a Predicate on a COUNT Expression

Paul White (@SQL_Kiwi) takes you on an optimizer journey, exploring how SQL Server comes up with cardinality estimates for COUNT queries.

Paul White : Changes to a Writable Partition May Fail Unexpectedly

Paul White (@SQL_Kiwi) shows how an update may fail when a partition has some data on a read-only filegroup, and explains several workarounds.

Aaron Bertrand : More showplan improvements? Yes, please!

Aaron Bertrand (@AaronBertrand) highlights a handful of Connect items aimed at improving SQL Server showplan diagnostics and query tuning in general.

Paul White : Internals of the Seven SQL Server Sorts – Part 1

Paul White (@SQL_Kiwi) rolls up his sleeves in his usual way, showing off the debugger several times while explaining the internals of SQL Server sorts.

Statistics – What, why and how (Part 2)

Lori Edwards (@loriedwards) continues her series on SQL Server statistics, explaining how the optimizer uses cardinality estimates.

Statistics – What, why and how (Part 1)

Lori Edwards (@loriedwards) starts a new series on statistics in SQL Server. In her first post, she discusses what they are and how they are created.