Not every key lookup needs fixing. Rank statements by reads, find the lookups with XQuery, then test the smallest index change on one call.
SQL SERVER – Using MAXDOP 1 for Single Processor Query – SQL in Sixty Seconds #008 – Video
Some queries run best on one CPU. In this sixty second video I show how to restrict such a query to a single processor with OPTION (MAXDOP 1).
Computed Column UDFs: Why Every Query on the Table Goes Serial
A computed column that calls a scalar function can block parallel plans for queries that never read it. Here is how to spot it and test a fix.
SQL SERVER – Table Variables and Transactions – SQL in Sixty Seconds #007 – Video
Many developers expect a rollback to undo changes in a table variable. This sixty second video on table variables and transactions shows it does not.
Why a Second Log File Does Not Make Anything Faster
Adding a second log file feels like a speed fix, but it is only a spare room. Here is how to watch it work and how to retire it.
Why a Clustered Index Does Not Guarantee Order Without ORDER BY
Explain order without ORDER BY through parallel scans, NOLOCK allocation scans, alternate indexes, shared scans, and the explicit sort fix.
SQL SERVER – Finding Shortest Distance between Two Shapes using Spatial Data Classes – Ramsetu or Adam’s Bridge
Using ShortestLineTo in SQL Server spatial data classes, I find the shortest distance between two shapes, with a fun Ramsetu, or Adam’s Bridge, example.