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Showplan Operator of the Week – BookMark/Key Lookup

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Analyzing I/O Characteristics and Sizing Storage Systems for SQL Server Database Applications

Understanding how to analyze the characteristics of I/O patterns in the Microsoft® SQL Server® data management software and how they relate to a physical storage configuration is useful in determining deployment requirements for any given workload. A well-performing I/O subsystem is a critical component of any SQL Server application. I/O subsystems should be sized in the same manner as other hardware components such as memory and CPU. As workloads increase it is common to increase the number of CPUs and increase the amount of memory. Increasing disk resources is often necessary to achieve the right performance, even if there is already enough capacity to hold the data.

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Question of the Day

Running SQLCMD II

I run this command to start SQLCMD:

sqlcmd -S localhost -E -c "proceed"
At the prompt, I type this (the 1> and 2> are prompts):
1> select @@version
2> go
What happens?

See possible answers