Category: Starting SQL

Mostoftentimes

There is a good solution to alleviating parameter sniffing. Ones I commonly use are:

• Temp tables
• Changing indexes
• Dynamic SQL

There isn’t really a good place to put a temp table in this stored proc, though I did blog …

Down And Out

There are lots of different ways that parameter sniffing can manifest in both the operators chosen, the order of operators chosen, and the resources acquired by a query when a plan is compiled. At least in my …

Pick A Database, Any Database

Alright, maybe not any database. Let’s stick with SQL Server. That’s the devil we know.

At some point in your life, you’re going to construct a query that takes user input, and that input is …

Nothing, Nothing, Nothing

Aside from the obvious perils of SQL Injection, parameterizing queries can be helpful in other ways.

Not to downplay SQL Injection at all, it’s just that fixing code is only one part of the equation. Vendor …

Parameter Positive

There are many good reasons to parameterize a query, but there are also trade-offs. There’s no such thing as a free parameter, as they say.

In this post, we’re going to discuss what is and isn’t a parameter, …

Put On

There are lots of things that can be fine in one query plan, and horrible in another.

Likewise, a query plan might be great for one set of parameters, and terrible for another. That’s called parameter sniffing, and …

Mild Best Wishes

Microsoft has chosen some odd things to warn us about in query plans. For estimated and cached plans, I totally understand some of the limitations.

Though the DMVs for queries associated with query plans (both in the …

Oh look, XML

One of my favorite pieces of SQL Server documentation is the XML schema for query plans.

Whenever I’ve needed to figure something out to query the plan cache, or when I’ve been looking for stuff that …

Well, well, well

So you’re that odd soul who has been listening to rumors about table variables. Perhaps things about them only being in memory, or that they’re okay to use if you only put less than some arbitrary number …

Hot To Trot

Most of the time when the optimizer thinks an index will make a big enough difference, it’ll tell you.

Sure, it’s not perfect, but it can get you where you’re going fast enough. If you’re relying on …