今天需要实现一个随机取出表里的数据一部分数据，发现通过sample来实现即方便效率又高，在此记录一下：
select * from emp4 sample(1) where rownum <10;【0.06s】select * from (select * from emp4 order by dbms_random.random) where rownum < 10;【0.7s】
来自 “ ITPUB博客 ” ，链接：https://blog.itpub.net/10130206/viewspace-659613/ ，如需转载，请注明出处，否则将追究法律责任。
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