PL/SQL SELECT *
FROM (
SELECT *
FROM mytable
ORDER BY
dbms_random.value
)
WHERE rownum <= 1000 http://www.orafaq.com/wiki/SQL_FAQ#Can_one_retrieve_only_the_Nth_row_from_a_table.3F
http://www.orafaq.com/wiki/SQL_FAQ#Can_one_retrieve_only_rows_X_to_Y_from_a_table.3F