We have performed a project running on ORACLE DB 11G / APEX 5.1.3 on the server where ORACLE 12.2C / APEX 18.1 is installed,
but an error occurred in the select of the table containing XMLType.
The error content is "Error Stack: ORA - 00904:" SYS "." ANYDATA "." CONVERTXMLTYPE ": Invalid identifier.
If you look at the problem table in the APEX browser data display, the same error is still displayed, but if you select it with the APEXsql command, it will display correctly.
When selecting a table containing XMLType in the APEX browser and APEX application
"Error Stack: ORA - 00904:" SYS "." ANYDATA "." CONVERTXMLTYPE ": Invalid identifier."
The APEX version is 18.1.