模糊查询 like ‘%/_% escape ‘/’’ 把‘/’定义为转义符 topN查询(rownum) select * from (select 字段 from 表 order by 排序字段) where rownum <= n rownum只能是小于等于”<=”n. 如果想实现大于等于,或者between,则如下代码: select * from (select rownum mynum, 字段 from表) where mynum >= 2 and mynum <=4