原文链接:http://www.javaarch.net/jiagoushi/703.htm
各个数据库获取随机列的语法
MySQL
SELECT column FROM table ORDER BY RAND() LIMIT 10
Oracle
SELECT column FROM( SELECT column FROM table ORDER BY dbms_random.value ) WHERE rownum <= 10
PostgreSQL
SELECT column FROM table ORDER BY RANDOM() LIMIT 10
SQL Server
SELECT TOP 10 column FROM table ORDER BY NEWID()