1. base64 的解密函数
select utl_raw.cast_to_varchar2(utl_encode.base64_decode(utl_raw.cast_to_raw(‘dGVzdA==‘))) from dual
2. base64 的加密函数
select utl_raw.cast_to_varchar2(utl_encode.base64_encode(utl_raw.cast_to_raw(‘test‘))) from dual
原文：http://www.cnblogs.com/princessd8251/p/4844584.html