ORA-31061: XDB error: special char to escaped char conversion failed.

I encountered this exception while trying to get the XML data for a query while I was using

dbms_xmlgen.getXML function in oracle.

Problem :

I found that one of the varchar columns in my table had invalid xml characters in it , so whenever the query was trying to fetch a record having that column with invalid data oracle was showing me the error as

ORA-31061: XDB error: special char to escaped char conversion failed.

For a list of invalid xml characters please see below

List of invalid XML chars

Solution :

The best solution I can think of is to update that column and remove the invalid xml characters , and make sure by adding a trigger rule that nobody can enter those characters again in any similar field.