Getting The Top Value Per Group In SQL Server: Row Number vs. Cross Apply Performance

Introductions


There are many ways to express queries in SQL. How different rewrites perform will largely be a function of:

  • You not doing anything ridiculous
  • Queries having good indexes in place
  • The optimizer not seeing through your tricks and giving

Using Batch Mode for the “Matching Supply With Demand” Challenge

Itzik Ben-Gan posted an interesting T-SQL challenge on SQL performance dot com. I’m writing up my solution in my own blog post because I have a lot to say and getting code formatting right can be tricky in blog post …

Annoyances When Indexing For Windowing Functions In SQL Server

One Day


I will be able to not care about this sort of thing. But for now, here we are, having to write multiple blogs in a day to cover a potpourri of grievances.

Let’s get right to it!

First, …

An Overlooked Benefit Of Batch Mode For Parallel Query Plans In SQL Server

Make It Count


When queries go parallel, you want them to be fast. Sometimes they are, and it’s great.

Other times they’re slow, and you end up staring helplessly at a repartition streams operator.

Sometimes you can reduce the problem …