March 17, 2008

How To Return Random Records From A Table

Let us see how to return random 'n' records from a table

-- SAMPLE SCRIPT

CREATE TABLE #Customers (id integer, cname varchar(20), pincode int)

-- INSERT SAMPLE RECORDS

INSERT INTO #Customers VALUES (1, 'Jack',45454 )
INSERT INTO #Customers VALUES (2, 'Jill', 43453)
INSERT INTO #Customers VALUES (3, 'Tom', 43453)
INSERT INTO #Customers VALUES (4, 'Kathy', 223434)
INSERT INTO #Customers VALUES (5, 'David', 65443)
INSERT INTO #Customers VALUES (6, 'Kathy', 456556)
INSERT INTO #Customers VALUES (7, 'Kim', 65443)

-- Return 3 random records from the #Customers table

SELECT TOP 3 cname,pincode FROM #Customers ORDER BY NEWID()

So what happens over here is that the NEWID() is used to generate a unique value of type uniqueidentifier. So ordering the results by this ID every time gives us random rows. Cool!!


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

1 comment:

Bill Jameson -- RaceTrac Atlanta said...

This is cool. Thanks