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sql - Select a random sample of results from a query result

This question asks about getting a random(ish) sample of records on SQL Server and the answer was to use TABLESAMPLE. Is there an equivalent in Oracle 10?

If there isn't, is there a standard way to get a random sample of results from a query set? For example how can one get 1,000 random rows from a query that will return millions normally?

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SELECT  *
FROM    (
        SELECT  *
        FROM    mytable
        ORDER BY
                dbms_random.value
        )
WHERE rownum <= 1000

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