The SELECT TOP N query always return exactly N records, and arbitrarily drops any record that have the same value as the last record in the group. To see what this means in practice, execute the following query against the Pubs database in SQL Server 7.0:

SELECT TOP 5 price, title FROM titles ORDER BY price DESC

The last title (it should be “The Busy Executive’s Database Guide”) has a price tag of $19.99. The Titles table, however, contains two more books with the same price, but they are ignored by the TOP clause. To see them you must add the WITH TIES clause, as in:

SELECT TOP 5 WITH TIES price, title FROM titles ORDER BY price DESC

The same rule applies to the TOP N PERCENT clause. Try executing the following query with and without the WITH TIES clause:

SELECT TOP 25 PERCENT WITH TIES price, title FROM titles ORDER BY price DESC