问一个10进制转16进制的问题

[spland]

用to_char(1,'XXXXXX')不符合我现在的要求
比如to_char(255,'XXXXXX')结果是FF,但length是6
我想要length也是2，不知道怎么实现

[waterfirer]

to_char(255,'XXXXXX')结果是FF,但length是6？
是7吧
to_char(255,'XX')结果是FF,但length是3

[heyixiang]

SQL> select length(trim(to_char(255,'XXXXXX'))) from dual;

LENGTH(TRIM(TO_CHAR(255,'XXXXX
------------------------------
2

SQL> select length(trim(to_char(255,'XX'))) from dual;

LENGTH(TRIM(TO_CHAR(255,'XX'))
------------------------------
2

SQL> select length(trim(to_char(15,'XX'))) from dual;

LENGTH(TRIM(TO_CHAR(15,'XX')))
------------------------------
1

[heyixiang]

SQL> select length(to_char(16,'XXXXXX')) from dual;

LENGTH(TO_CHAR(16,'XXXXXX'))
----------------------------
7