oracle函数之：translate

今天在阅读一份document的时候发现了一个函数：translate
先看看语法及其介绍吧。

TRANSLATE(char, from, to)
Returns Char with all occurrences of each character in From replaced by its corresponding characte r in To.
Characters in Char that are not in From are not replaced.

示例
SQL> select translate('asdfasdfaaa','a','#') from dual;
TRANSLATE('ASDFASDFAAA','A','#
------------------------------
#sdf#sdf###
SQL> select translate('asdfasdfaaa','ad','#') from dual;
TRANSLATE('ASDFASDFAAA','AD','
------------------------------
#sf#sf###
SQL> select translate('asdfasdfaaa','da','#') from dual;
TRANSLATE('ASDFASDFAAA','DA','
------------------------------
s#fs#f
SQL>

有点看不太明白，在一开始的时候，特别是第2、3个，摸了1、2分钟才搞明白。其实也挺简单的，就是replace的超集罢了，注意第2、3个参数就好了，重点就在这。