Tuesday, October 19, 2010

What should you know more about NOLOCK?

As you may know already, NOLOCK is used in some queries to avoid, SQL Server to acquire shared locks on the records being red. The main reason to use nolock is to eliminate the performance overhead, especially for large data sets, due to shared locks. Though you have the gain in performance wise, it also gives you dirty records (uncommitted data).

This article explains another behavior of nolock.
Let’s create a sample table with test data to illustrate the behavior.

Sunday, October 17, 2010

Shortcut to view tables

As a DBA I need to see the list of tables available in a particular database frequently. Traditionally, this can be done by traversing through the object explorer. This may be the popular method among GUI lovers. But for me it is a pain. I hope it is the same for most of the DBAs.

How to interpret Disk Latency

I was analyzing IO stats in one of our SQL Servers and noticed that IO latency (Read / Write) are very high. As a rule of thumb, we know tha...