Common SQL Server Consulting Advice: Enabling An Optimistic Isolation Level

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One of the very first performance problems that developers will run into when using SQL Server is locking, and often deadlocks.

Though deadlocks have their root in (b)locking behavior, not all blocking leads to deadlocks.

Some (b)locking …

Is Read Uncommitted (NOLOCK) An Optimistic Or Pessimistic Isolation Level?

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I ran a Twitter poll recently, because as I was writing another blog post, I wasn’t quite sure how to group uncommitted/nolock between pessimistic or optimistic isolation levels.

Blocking on Columnstore Indexes that RCSI and NOLOCK Don’t Resolve

I recently ran into a production issue where a SELECT query that referenced a NOLOCK-hinted table was hitting a 30 second query timeout. Query store wait stats suggested that the issue was blocking on a table with a nonclustered columnstore …