关于字符串转换的问题

Question

SQL> select to_number('0A','XX') from dual;TO_NUMBER('0A','XX')
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                  10SQL>

Answer 1

二进制转为10进制SQL> SELECT BIN_TO_NUM(1,0,1,0) FROM DUAL;BIN_TO_NUM(1,0,1,0)
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                 10SQL> SELECT BIN_TO_NUM(1,0,1,1) FROM DUAL;BIN_TO_NUM(1,0,1,1)
-------------------
                 11
十进制与十六进制转换
TO_CHAR(100,'XXXX')=64; TO_CHAR(255,'XXXX')=FF ; TO_CHAR(1000,'XXXX')=3E8
TO_NUMBER('64','XXXX')=100; TO_NUMBER('FF','XXXX')=255