Paul White (@SQL_Kiwi) is an independent SQL Server technical consultant with 20 years experience, specializing in performance tuning the SQL Server Core Engine, and is well known for his expertise in execution plans, the query processor, and the query optimizer. Currently living in New Zealand, Paul writes the SQL Server internals blog Page Free Space.
Over the years, Paul has worked internationally on a number of high-volume critical systems where ultimate performance and reliability were the primary goals. A SQL Server MVP since 2011, he contributes regularly to a range of web sites and forums, including Database Administrators Stack Exchange. Paul has also spoken at a variety of user groups and community events such as SQL Saturdays and the annual SQL Pass Summit.
With detailed information and his uncanny knack for explaining technical concepts very well, Paul White (@SQL_Kiwi) concludes his series on ACID, transactions, and isolation levels in SQL Server with a great read on READ UNCOMMITTED.
Paul White (@SQL_Kiwi) looks at a couple of cases where – even though T-SQL is supposed to be a declarative language, and any query that uses the same logic and same semantics should ultimately lead to the same plan and comparable performance – rewriting queries can change the plan in dramatic ways.