Tom Zíka

I'm still sticking around, but since everyone is leaving Twitter, you can find me on Slack dbatools.io/slack and LinkedIn linkedin.com/in/tomas-zika/

Today in SQL Server things that have been hilariously broken for 16 years: If you 'force' a plan (using any method, including Plan Guides, Query Store, and Automatic Plan Correction) the resulting plan will have its query_hash overwitten by the query_plan_hash. In other words, both plan hash and query plan hash will be given the query plan hash value. The real query hash value is simply lost 🤦‍♂️ This will break anything you have that uses query_hash for any purpose, including scripts and tools. Example repro: 1. Create a table 2. Select from it 3. Capture the XML showplan for the select 4. Run the select again with the XML in a USE PLAN hint Online demo at dbfiddle.uk/ASmaZcJ- In that example, the resulting plan contains: QueryHash="0x10D77A8E4F35F994" QueryPlanHash="0x10D77A8E4F35F994" Notice the identical hashes. This bug affects SQL Server 2008 to 2022 CU16 inclusive. Until Microsoft fix this (and backport it to 2008 🤣) any plans subject to 'forcing' will have an incorrect query hash🥳 Note: Only guided plan search is affected. Supplying individual query hints (except USE PLAN of course) in a plan guide (or via an equivalent feature) does not provoke this misbehaviour.

@British_Airways so you take the money for the seat reservation, assign me completely different seats, and then ghost me for two months (and counting) when I request a refund?

I had to get this off my chest Blog post: Why is fn_xe_file_target_read_file the worst SQL function? straightforwardsql.com/posts/why-is-f…

Having some recursive fun with DMVs Blog post: Finding nested references straightforwardsql.com/posts/finding-…

@erikdarlingdata Even a blank Czech?

i will autograph anything you hand me 😂

My #tsql2sday entry. Blog post: Database CI/CD Basics (T-SQL Tuesday #177) straightforwardsql.com/posts/database…

My plan backfired

Very niche blog post --- Blog post: Service Broker Blocking straightforwardsql.com/posts/service-…

📬 The Decline in Microsoft SQL Server Support: Why Your Business Deserves Better, And How I Can Help: ift.tt/gY1Wv9J 📬

Currently reading: Why are Columnstore Key Lookups Bad – Forrest Shares Stuff (forrestmcdaniel.com)

My personal preferences, tips and tricks when setting up SSMS Blog post: My Toolbox - SSMS straightforwardsql.com/posts/my-toolb…

New blog post: Everything's a case statement! I was having a fun discussion in the SQL Server slack community about how things like IIF, COALESCE, etc are just syntactic sugar for CASE statements. So I thought I'd throw together a blog post about it... chadbaldwin.net/2024/07/30/eve…

Great question and even better answer dba.stackexchange.com/questions/3412…

I had another idea for a SQL movie poster parody today.

It's been a little over 2 years since my last blog post. I finally got around to throwing one together after some encouragement from a few people on the SQL Server Community Slack. chadbaldwin.net/2024/07/09/fun…

Lack of planning on your part does not justify moving to the cloud on my part.