Constraints on a XMLTYPE table

Question

Hi,
Has anyone been able to construct constraints on a XMLTYPE table as shown on page 5-52 of the XDB Developers
guide.
Whatever I try I get errors:
create table poc_wip2 of xmltype
element "http://www.derwent.co.uk/wpi.xsd#WPI"
(unique(XMLDATA.WPI_TYPE.BibPt2645_T.co))
(unique(XMLDATA.WPI_TYPE.BibPt2645_T.co))
ERROR at line 3:
ORA-00922: missing or invalid option
create table poc_wip2 p of xmltype
element "http://www.derwent.co.uk/wpi.xsd#WPI"
(unique(extract(value(p),/WPI/BibPt@co')))
create table poc_wip2 p of xmltype
ERROR at line 1:
ORA-00922: missing or invalid option
What I would like to be able to do is to define a primary key constraint based on three attribute values. Is this possible
using XMLTYPE?
Thanks
Pete

Answer 1

Peter
Remember that the attribute names generated from the Schema are case sensitive bu SQL is not. You will have to use something like XMLDATA.WPI_TYPE."BibPt2645_T"."co" in the constraint definition
It may be easier to create the table via registerSchema and then alter the constraint onto the table..
EG.
alter table purchaseorder
add constraint REFERENCE_IS_UNIQUE
unique (xmldata."Reference")
alter table purchaseorder
add constraint USER_IS_VALID
foreign key (xmldata."User") references SCOTT.emp(ename)
create trigger VALIDATE_PURCHASEORDER
before insert on purchaseorder
for each row
declare
XMLDATA xmltype;
begin
XMLDATA := :new.sys_nc_rowinfo$;
xmltype.schemavalidate(XMLDATA);
end;
--quit
The reason for this is that if you want to keep a table created from a schema in_sync with the resource view you need to call
dbms_xdbz.enableHierarchy(SCHEMA,TABLE) after creating the table..