日期:2014-05-17  浏览次数:20819 次

extend用法
请问:我想在一可变数组最后加一个元素 "ball ",   用extend应该怎么写啊?
exists怎么用?

------解决方案--------------------
1.Never used extend before. Below method is OK.
select CONCAT(RTRIM( 'aa ', ' ' ' '), 'ball ') from dual
2. Simple sample for exists method.
select ID from tablename
where exists( select id from tablename where id > 10)