Blocked Queries and the Plan Cache

Erik Darling lays out an argument why execution time isn’t always a great measure for finding bad queries:

Most scripts (even ones I’ve worked on!) that look at the plan cache, have had the ability to sort it by different metrics: CPU, reads, writes, duration, etc.

A lot of people are very interested in long running queries — and I am too!

Heck, they’re how I make money. Blogging pays like crap.

But there’s a slight problem with only looking at query duration.

Read on for an example. Erik loses money on every blog post but he makes up for it in volume.

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Batch Mode Normalization

Paul White digs into batch mode normalization and its consequences for performance: I mentioned in the introduction that not all eight-byte data types can fit in 64 bits. This fact is important because many columnstore and batch mode performance optimizations only work with data 64 bits in size. Aggregate pushdown is one of those things. There are […]

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Comparing CAST and CONVERT Performance

Max Vernon runs a performance test of CAST versus CONVERT: This post is a follow-up to my prior post inspecting the performance of PARSE vs CAST & CONVERT, where we see that PARSE is an order of magnitude slower than CONVERT. In this post, we’ll check if there is a similar difference between using CAST or CONVERT. But just to be clear, CONVERT offers […]

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