Range partition by a virtual column derived from XMLTYPE

Question

I want to create table and partition it by interval partion (range partition) on a virtual column which is derived from XMLTYPE i get ora-14513 error.
create table dicom_archive_virtual
id integer not null primary key,
parent_id integer, -- where this image is created from
dcm_filename varchar2(60), -- DICOM image file name from import
description varchar2(100), -- description of the image
dicom orddicom, -- DICOM data
image ordimage, -- DICOM data in JPEG format
thumb ordimage, -- DICOM data in JPEG thumbnail
metadata xmltype, -- user customized metadata
isAnonymous integer, -- accessible flag for the research role.
study_date date as
(to_date(substr(extractValue(metadata,'//DATE/text()'),1,10),'yyyy-mm-dd')) virtual)
PARTITION BY RANGE (study_date)
INTERVAL(NUMTOYMINTERVAL(1, 'MONTH'))
( PARTITION p_2005 VALUES LESS THAN (TO_DATE('1-1-2006', 'DD-MM-YYYY')),
PARTITION p_2006 VALUES LESS THAN (TO_DATE('1-1-2007', 'DD-MM-YYYY')),
PARTITION p_2007 VALUES LESS THAN (TO_DATE('1-1-2008', 'DD-MM-YYYY'))
Study_date is a virtual colum which is derived from the column metadata which is of type XMLTYPE,so when i partition on this virtual column i get the follwoing error
SQL Error: ORA-14513: partitioning column may not be of object datatype
So i want to know whether this is not possible or there is any other alternative to achieve this.

Answer 1

I want to create table and partition it by interval partion (range partition) on a virtual column which is derived from XMLTYPE Congratulations on trying to fit as many cutting edge techniques into a single line as possible.
So i want to know whether this is not possible ...The error message is pretty unequivocal.
...or there is any other alternative to achieve this.What you could try is materializing the virtual column, i.e. adding an actual date column which you populate with that code in the insert and update triggers. Inelegant but then complexity often is.
Cheers, APC
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