Execute the following Microsoft SQL Server Transact-SQL (T-SQL) script in Management Studio (SSMS) Query Editor, SQLCMD or other client software to create a huge temporary test table:

use AdventureWorks;

select top 1000000000
ID = identity(int,1,1), ColA = left(a.Name,1),
ColB = left(b.Name, 2), ColC = left(c.Name, 3)
into #testLargeTable
from sys.syscolumns a, sys.syscolumns b, sys.syscolumns c ;