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phoen08
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Replace Oracle hex values

I'm having an issue with hex values being stored in an oracle database.   The fields containing the hex values appear to be null whenever I search for null values in the database.   The oracle data is being written to an XML file.  However, when I try to validate the XML, I receive the following error:

', hexadecimal value 0x0C, is an invalid character

Is there anyway to identify and replace hex characters in oracle?  I would like to fix this in my stored procedure before the data is accessed by the .net application.  

Thanks
Oracle Database.NET Programming

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slightwv (䄆 Netminder)

8/22/2022 - Mon
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slightwv (䄆 Netminder)

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gatorvip

0x0C is form feed (\f)

http://en.wikipedia.org/wiki/ASCII#ASCII_control_characters

As slightwv says, "space" includes a form feed character
http://psoug.org/reference/regexp.html
phoen08

ASKER
The replace function slightwv provided works great but I'm afraid I may need to trap all invalid hex characters.  I'm thinking about writing a method in .NET to remove all invalid characters from the XML file before they are validated.  

I'm not sure why the column containing the hex OC value returns null when I peform a select query.  When the column value is written to the XML file it contains the hex values and also valid text
slightwv (䄆 Netminder)

>>sure why the column containing the hex OC value returns null when I peform a select query.

What makes you think it is retuning 'null'?   Displaying a non-printable character on the screen might 'appear' to be null but the database has a value for that column.

>>but I'm afraid I may need to trap all invalid hex characters.

You can tweak the function to replace everything EXCEPT a list of  'valid' chacters but you need to define what is 'valid'.

There are a few other character classes similar to SPACE that might work for you.
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James Murphy
phoen08

ASKER
>>What makes you think it is retuning 'null'?   Displaying a non-printable character on the screen might 'appear' to be null but the database has a value for that column.

I tested the value for null on the oracle side.  I know the value is returning null because I used the NVL fuction to replace null with 0.  Also used a select query to find the column that "is null".
slightwv (䄆 Netminder)

If it is stored as a true 'null' in oracle, then something else is adding the HEX value.

It is impossible for "nvl(column,0)" to return a 0 if the column contains a '0C'.  Either impossible or a pretty huge bug in your version of Oracle.