TABLESAMPLE SYSTEM (1000 ROWS)
Explanation:
Update line 3 to get the following:
SELECT *
FROM Customers
TABLESAMPLE SYSTEM (1000 ROWS)
The TABLESAMPLE clause limits the number of rows returned from a table in the FROM clause to a sample number orPERCENT of rows.
Syntax: TABLESAMPLE [SYSTEM] (sample_number [ PERCENT | ROWS ] )
References: https://technet.microsoft.com/en-us/library/ms189108(v=sql.105).aspx