March 04, 2008

Passing parameter to the TOP clause

The TOP clause in SQL Server 2005 has been enhanced. You can now specify an expression as the number definition in the TOP clause. This makes your TOP clause dynamic as you can pass the number value in a variable and use that variable in the TOP clause of your T-Sql query

Sample Usage:


DECLARE @TopVar AS int
SET @TopVar = 20


SELECT TOP(@TopVar)
CustomerID,CompanyName, ContactName
FROM Northwind.dbo.Customers


About The Author

Suprotim Agarwal, ASP.NET Architecture MVP works as an Architect Consultant and provides consultancy on how to design and develop Web applications.

Suprotim is also the founder and primary contributor to DevCurry, DotNetCurry and SQLServerCurry. He has also written an EBook 51 Recipes using jQuery with ASP.NET Controls.

Follow him on twitter @suprotimagarwal

6 comments:

Anonymous said...

it is very good.It solve my problem.

Anonymous said...

Have you had any luck using this in a VS2005 report?

Suprotim Agarwal said...

I do not think that should be any problem. Are you facing one?

Anonymous said...

I am attempting to use this in VS2005 writing a Reporting Services report.

However, I am receiving the error "The number of rows in a TOP clause must be an integer".

The parameter within the report is set as an integer. It seems VS is sending the parameter value as something other than an integer?

Christophe Vanderhaeghen said...

It's indeed a clean and easy solution, but there is a catch: it works really slow and for larger tables you'll notice significant performance-loss!

My 2 cents

Praveen said...

For SQL SERVER 2000, there is workaround and please take a look at it here.
http://praveenbattula.blogspot.com/2011/01/using-variables-in-top-clause-in-t-sql.html