Oracle: How do I convert hex to decimal in Oracle SQL?

Question

How do I convert hexadecimal to decimal (and back again) using Oracle SQL?

Answer 1

Starting in Oracle8i, the TO_CHAR and TO_NUMBER functions can handle conversions from base 10 (decimal) to base 16 (hexadecimal) and back again:

SQL> select to_char(123,'XX') to_hex, 
2    to_number('7B','XX') from_hex   
3   from dual  
4  /   
TO_     FROM_HEX
------  -----------------
7B     123

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