Make a T-SQL Query Sleep for a certain amount of time

At times, in test scenarios, you may want to emulate that a transaction or a T-SQL query takes ‘x’ amount of time. Well that is possible (although not with precision) in SQL Server (2005/2008) using the WAITFOR command.

Here’s an example of delaying query execution till a specified time interval has elapsed – let us say 10 seconds

USE Northwind
WAITFOR DELAY '00:00:10';
SELECT LASTNAME, FIRSTNAME FROM Employees;

OUTPUT

As you can see, we used the WAITFOR statement with a DELAY option to delay code execution for 10 seconds.

There are a couple of things you should note about the WAITFOR statement

- WAITFOR does not accept date values, only time values are allowed

- In some scenarios, the delay specified by you may not exactly the same as the delay caused by WAITFOR

About The Author

Suprotim Agarwal, MCSD, MCAD, MCDBA, MCSE, is the founder of DotNetCurry, DNC Magazine for Developers, SQLServerCurry and DevCurry. He has also authored a couple of books 51 Recipes using jQuery with ASP.NET Controls and a new one recently at The Absolutely Awesome jQuery CookBook.

Suprotim has received the prestigous Microsoft MVP award for nine times in a row now. In a professional capacity, he is the CEO of A2Z Knowledge Visuals Pvt Ltd, a digital group that represents premium web sites and digital publications comprising of Professional web, windows, mobile and cloud developers, technical managers, and architects.

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