https://straightforwardsql.com/categories/deep-dive/ Recent content in Deep Dive on StraightforwardSQL Hugo -- gohugo.io en-us Fri, 09 Aug 2024 16:09:14 +0200 https://straightforwardsql.com/posts/service-broker-blocking/ Fri, 09 Aug 2024 16:09:14 +0200 https://straightforwardsql.com/posts/service-broker-blocking/ I was paged for a blocking chain where the lead blocker had a transaction name I'd never seen: CSbRollbackHandlerTask::DisableQ. Here is how I reproduced it and why the blocked process report refuses to help. https://straightforwardsql.com/posts/async-stats-update-causing-blocking/ Sun, 16 Jun 2024 20:00:27 +0200 https://straightforwardsql.com/posts/async-stats-update-causing-blocking/ An index rebuild quietly blocked an async stats update, and the whole server started timing out. Here is the lock-partitioning repro and the SQL Server 2022 fix. https://straightforwardsql.com/posts/are-abort_after_wait-victims-logged/ Sat, 18 May 2024 21:10:20 +0200 https://straightforwardsql.com/posts/are-abort_after_wait-victims-logged/ Does ALTER INDEX REBUILD with WAIT_AT_LOW_PRIORITY log its victims in the error log the same way KILL does? Let's find out. https://straightforwardsql.com/posts/scary-scalar-functions-your-environment/ Sun, 02 Oct 2022 20:40:04 +0200 https://straightforwardsql.com/posts/scary-scalar-functions-your-environment/ You've learned why Scalar UDFs are slow and how to remove them. The last question: where do you even start? Here's how I triage them across a whole environment. https://straightforwardsql.com/posts/scary-scalar-functions-the-cure/ Sun, 24 Jul 2022 11:45:04 +0200 https://straightforwardsql.com/posts/scary-scalar-functions-the-cure/ Nuke them from orbit, or inline them. The practical ways to neutralize Scalar UDF performance pain, from a free SCHEMABINDING win to a full ITVF rewrite. https://straightforwardsql.com/posts/scary-scalar-functions-performance/ Sat, 02 Jul 2022 14:21:57 +0200 https://straightforwardsql.com/posts/scary-scalar-functions-performance/ A Scalar function that does literally nothing still runs over 20 times slower. Here is the proof, measured four different ways. https://straightforwardsql.com/posts/scary-scalar-functions-parallelism/ Tue, 21 Jun 2022 13:21:35 +0200 https://straightforwardsql.com/posts/scary-scalar-functions-parallelism/ Consultants hate me for this one weird trick. Because I'll be uncovering all the mess Scalar functions can cause in a series of articles. https://straightforwardsql.com/posts/new-extended-events-in-sql-server-2022/ Tue, 24 May 2022 18:33:05 +0200 https://straightforwardsql.com/posts/new-extended-events-in-sql-server-2022/ SQL Server 2022's CTP has dropped. I diffed its Extended Events against 2019 and pulled out the few new ones worth a look. https://straightforwardsql.com/posts/keep-plan-demystified/ Thu, 07 Apr 2022 18:56:37 +0100 https://straightforwardsql.com/posts/keep-plan-demystified/ Ever wondered what the KEEP PLAN hint actually does? The docs are vague, so I tested it against every recompilation threshold to find out. https://straightforwardsql.com/posts/query-store-default-settings/ Thu, 23 Sep 2021 22:03:31 +0200 https://straightforwardsql.com/posts/query-store-default-settings/ Query Store comes with default settings - but are they what the documentation says? Let's find out using a simple Extended Events session.