ERROR: ORA-19025: EXTRACTVALUE returns... after a deleteXML command.

Question

Hi
My Oracle details are:
Oracle Database 11g Release 11.2.0.2.0 - 64bit Production
PL/SQL Release 11.2.0.2.0 - Production
CORE 11.2.0.2.0 Production
TNS for Solaris: Version 11.2.0.2.0 - Production
NLSRTL Version 11.2.0.2.0 - Production
I'm getting the following error:
ERROR:
ORA-19025: EXTRACTVALUE returns value of only one node
when I try and select the content of a row after I have performed an deleteXML command on a node from with in the xml content.
This process can reproduced the error.
CREATE TABLE test OF XMLType xmltype STORE as BINARY XML;
INSERT INTO test VALUES (XmlType('<product_details id="1"><product id="21"><name>test1</name><code>123</code></product><product id="20"><name>test2</name><code>456</code></product></product_details>'));Select the xml content...
SELECT extract(OBJECT_VALUE, '/product_details[@id=1]') "Xml" FROM test WHERE XMLEXISTS('/product_details[@id=1]' PASSING OBJECT_VALUE);
<product_details id="1">
  <product id="21">
    <name>test1</name>
    <code>123</code>
  </product>
  <product id="20">
    <name>test2</name>
    <code>456</code>
  </product>
</product_details>then delete the product node with id = 21 from the xml content...
UPDATE test SET OBJECT_VALUE = deleteXML(OBJECT_VALUE, '/product_details[@id=1]/product[@id=21]')  WHERE XMLEXISTS('/product_details[@id=1]' PASSING OBJECT_VALUE);
1 row updated.The same select now produces the following error:
SELECT extract(OBJECT_VALUE, '/product_details[@id=1]') "Xml" FROM test WHERE XMLEXISTS('/product_details[@id=1]' PASSING OBJECT_VALUE);
ERROR:
ORA-19025: EXTRACTVALUE returns value of only one node
no rows selectedThe current content of the test table is:
SELECT * FROM test;
<product_details id="1">
  <product id="20">
    <name>test2</name>
    <code>456</code>
  </product>
</product_details>I would now expect the select statement:
SELECT extract(OBJECT_VALUE, '/product_details[@id=1]') "Xml" FROM test WHERE XMLEXISTS('/product_details[@id=1]' PASSING OBJECT_VALUE);
to return:
<product_details id="1">
  <product id="20">
    <name>test2</name>
    <code>456</code>
  </product>
</product_details>Can anyone tell me why this select is not returning any rows and an error message?
Having done some more research around this problem, it would seem that deleting the last node first ie the node with the product id of 20 does not cause the error!
eg running the following deleteXML works as I would expect:
UPDATE test SET OBJECT_VALUE = deleteXML(OBJECT_VALUE, '/product_details[@id=1]/product[@id=20]')  WHERE XMLEXISTS('/product_details[@id=1]' PASSING OBJECT_VALUE);
1 row updated.then running...
SELECT extract(OBJECT_VALUE, '/product_details[@id=1]') "Xml" FROM test WHERE XMLEXISTS('/product_details[@id=1]' PASSING OBJECT_VALUE);
<product_details id="1">
  <product id="21">
    <name>test1</name>
    <code>123</code>
  </product>
</product_details>returns what I would expect.
Many thanks
Edited by: Baseman on 20-Apr-2011 16:55
Edited by: Baseman on 20-Apr-2011 17:00

Answer 1

I tried it myself and found something very strange. It seems when using xmltype with binary storage, that oracle isnt able to read xmldata, the same way that it reads using clob storage.
Here is what I get if I use clob storage:
CREATE TABLE test_clob OF XMLType xmltype STORE as CLOB;
INSERT INTO test_clob VALUES (XmlType('<product_details id="1"><product id="21"><name>test1</name><code>123</code></product><product id="20"><name>test2</name><code>456</code></product></product_details>'));
UPDATE test_clob SET OBJECT_VALUE = deleteXML(OBJECT_VALUE, '/product_details[@id=1]/product[@id=21]') 
WHERE XMLEXISTS('/product_details[@id=1]' PASSING OBJECT_VALUE);
SELECT extract(OBJECT_VALUE, '/product_details[@id=1]') "Xml"
FROM test_clob WHERE XMLEXISTS('/product_details[@id=1]' PASSING OBJECT_VALUE);
-- works fine and prints out:
<product_details id="1"><product id="20"><name>test2</name><code>456</code></product></product_details>
SELECT t.*, x.*
,extract(value(x), '/product_details/@id') id
FROM test_clob t, table (xmlsequence(extract(t.object_value,'/product_details'))) xThe last select statement prints out the "id" as "1" which we expected.
But if I use the same select statement in your example on a table test like this:
SELECT t.*, x.column_value
,extract(value(x), '/product_details/@id') id
FROM test t, table (xmlsequence(extract(t.object_value,'/product_details'))) xit prints out:
120
<name>test2</name>
<code>456</code>It seem it printed out the "id" from product_details, plus "id" from "product" plus all the data of the element product.
Edited by: Romci on 3.5.2011 13:16