21Jan 2019 by Grant Fritchey 1 Comment

Get Your Learn On

PASS, SQL Server
There is one truth that I can say about technology with an absolute certainty: It's going to change. Get your learn on! Technology is going to be shifting under your feet, constantly. Even if all you ever do is work with SQL Server, on premises, on hardware, without VMs, containers, clouds or any of that foofaraw, things are going to change. Dealing With Change What's the best way to deal with change? Get your learn on! Learning all the new stuff is absolutely necessary. It's unavoidable. Even if you're not running SQL Server 2019 in production today (and very few of you should be as I write this because it's still in preview) because you're still on SQL Server 2005 (and, by the way, support ended in April of 2016,…
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11Dec 2017 by Grant Fritchey 2 Comments

Execution Plan Metrics and Units of Measure

SQL Server, SQL Server 2016, SQL Server 2017
Have you ever looked at the properties inside an execution plan and wondered what the units of measure were? I know I have. I also get the question pretty frequently about all sorts of properties. What does EstimatedAvailableMemoryGrant display it's units in anyway? For that matter, what the heck is an EstimatedAvailableMemoryGrant? Showplan Schema and Units of Measure The answer to those questions and a whole lot more is pretty easy to find. You just have to look to the ShowPlan Schema. Microsoft has all the schema's published, going back to 2005. The next time you're faced with a question such as, what are the units of measure of the MemoryGrantInfo: Or, what the heck is SerialDesiredMemory and why is it exactly matching RequestedMemory, you just have to go and…
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12Dec 2016 by Grant Fritchey 7 Comments

OPTIMIZE FOR Hints When Parameter Sniffing is Turned Off

Azure, SQL Server, SQL Server 2016, T-SQL
While presenting recently and talking about dealing with bad Parameter Sniffing, I got the question; what happens to OPTIMIZE FOR hints when parameter sniffing is disabled? This is my favorite kind of question because the answer is simple: I don't know. Parameter Sniffing For those who don't know, parameter sniffing is when SQL Server uses the precise values passed into a query as a parameter (this means stored procedures or prepared statements) to generate an execution plan from the statistics using the value from the parameter. Most of the time, parameter sniffing is either helping you, or is not hurting you. Sometimes, parameter sniffing turns bad and hurts you quite severely. Usually, but not always, this is because you either have severely skewed data (some data is very different than the rest, lots…
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