Query failed after insert

Question

Hi everybody
I'm using Oracle 11g Release 11.2.0.3.0.
I have created this table (the schema also) :
CREATE TABLE DATA_XML (
NOUVEAUX_CODES_DATA XMLTYPE)
XMLTYPE NOUVEAUX_CODES_DATA STORE AS BINARY XML
XMLSCHEMA "chgt_codes_clients.xsd" ELEMENT "codes_clients"
DISALLOW NONSCHEMA;
I have inserted this row :
update snf_xml set nouveaux_codes_data = XMLType('<codes_clients><modif><ancien_code>TOTO - 000</ancien_code><nouveau_code>UNTEL - 000</nouveau_code><date>2008-07-23</date> <user>P.DUPONT</user><commentaire>PREMIER CHANGEMENT</commentaire></modif></codes_clients>');
No problem
I make this query :
select XMLQuery('for $i in /codes_clients/modif where $i/user="P.DUPONT" return <ok>{$i/date}</ok>'
passing nouveaux_codes_data returning content) DATE_MODIF from data_xml;
No problem, data is returned
I insert a new record, like this :
update snf_xml set nouveaux_codes_data = XMLQuery('copy $p := .modify (for $i in $p/codes_clients return insert node <modif><ancien_code>UNTEL - 000</ancien_code><nouveau_code>MACHIN - 000</nouveau_code><date>2008-07-23</date><user>J.DURAND</user><commentaire>DEUXIEME CHANGEMENT</commentaire></modif> into $i) return $p' passing nouveaux_codes_data returning content)
No problem
But the query : select XMLQuery('for $i in /codes_clients/modif where $i/user="J.DURAND" return <ok>{$i/date}</ok>'
passing nouveaux_codes_data returning content) DATE_MODIF from data_xml;
failed, no result
But the first query is still OK.
Where is the problem ?
Thanks in advance

Answer 1

Sounds like "déjà-vu", unfortunately...
This is not the first time we see bugs related to fragment insertion in schema-based documents.
I can reproduce the problem now :
begin
  dbms_xmlschema.registerSchema(
    schemaURL => 'chgt_codes_clients.xsd'
  , schemaDoc => '<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="codes_clients" type="modif_code"/>
<xs:complexType name="modif_code">
<xs:sequence>
<xs:element name="modif" type="new_code" maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>
<xs:complexType name="new_code">
<xs:sequence>
<xs:element name="ancien_code" type="xs:string"/>
<xs:element name="nouveau_code" type="xs:string"/>
<xs:element name="date" type="xs:date"/>
<xs:element name="user" type="xs:string"/>
<xs:element name="commentaire" type="xs:string"/>
</xs:sequence>
</xs:complexType>
</xs:schema>'
  , local => true
  , genTypes => false
  , genTables => false
  , enableHierarchy => dbms_xmlschema.ENABLE_HIERARCHY_NONE
  , options => dbms_xmlschema.REGISTER_BINARYXML
end;
CREATE TABLE DATA_XML of xmltype
XMLSCHEMA "chgt_codes_clients.xsd" ELEMENT "codes_clients" ;
insert into data_xml
values (
  xmlparse(document
  '<codes_clients>
  <modif>
    <ancien_code>TOTO - 000</ancien_code>
    <nouveau_code>UNTEL - 000</nouveau_code>
    <date>2008-07-23</date>
    <user>P.DUPONT</user>
    <commentaire>PREMIER CHANGEMENT</commentaire>
  </modif>
</codes_clients>')
commit;
SQL> alter session set nls_date_format = "DD/MM/YYYY";
Session altered.
SQL> select XMLCast(
  2           XMLQuery(
  3             'for $i in /codes_clients/modif
  4              where $i/user="P.DUPONT"
  5              return $i/date'
  6             passing object_value
  7             returning content
  8           )
  9           as date
10         ) DATE_MODIF
11  from data_xml;
DATE_MODIF
23/07/2008
SQL> update data_xml
  2  set object_value =
  3      XMLQuery(
  4        'copy $p := .
  5         modify (
  6           insert node $modif into $p/codes_clients
  7         )
  8         return $p'
  9        passing object_value
10              , xmlparse(content
11  '<modif>
12    <ancien_code>UNTEL - 000</ancien_code>
13    <nouveau_code>MACHIN - 000</nouveau_code>
14    <date>2013-04-25</date>
15    <user>J.DURAND</user>
16    <commentaire>DEUXIEME CHANGEMENT</commentaire>
17  </modif>') as "modif"
18        returning content
19      )
20  ;
1 row updated.
SQL> select XMLCast(
  2           XMLQuery(
  3             'for $i in /codes_clients/modif
  4              where $i/user="J.DURAND"
  5              return $i/date'
  6             passing object_value
  7             returning content
  8           )
  9           as date
10         ) DATE_MODIF
11  from data_xml;
DATE_MODIF
----------Checking the serialized document shows that the new item is really there :
SQL> set long 5000
SQL> set pages 100
SQL> select xmlserialize(document object_value) from data_xml ;
XMLSERIALIZE(DOCUMENTOBJECT_VALUE)
<codes_clients>
  <modif>
    <ancien_code>TOTO - 000</ancien_code>
    <nouveau_code>UNTEL - 000</nouveau_code>
    <date>2008-07-23</date>
    <user>P.DUPONT</user>
    <commentaire>PREMIER CHANGEMENT</commentaire>
  </modif>
  <modif>
    <ancien_code>UNTEL - 000</ancien_code>
    <nouveau_code>MACHIN - 000</nouveau_code>
    <date>2013-04-25</date>
    <user>J.DURAND</user>
    <commentaire>DEUXIEME CHANGEMENT</commentaire>
  </modif>
</codes_clients>Workaround : disable XQuery DML rewrite...
It'll prevent Oracle from using a piecewise update on the underlying storage. I suppose you won't see the difference on small docs.
SQL> roll;
Rollback complete.
SQL> update /*+ no_xml_dml_rewrite */
  2         data_xml
  3  set object_value =
  4      XMLQuery(
  5        'copy $p := .
  6         modify (
  7           insert node $modif into $p/codes_clients
  8         )
  9         return $p'
10        passing object_value
11              , xmlparse(content
12  '<modif>
13    <ancien_code>UNTEL - 000</ancien_code>
14    <nouveau_code>MACHIN - 000</nouveau_code>
15    <date>2013-04-25</date>
16    <user>J.DURAND</user>
17    <commentaire>DEUXIEME CHANGEMENT</commentaire>
18  </modif>') as "modif"
19        returning content
20      )
21  ;
1 row updated.
SQL> select XMLCast(
  2           XMLQuery(
  3             'for $i in /codes_clients/modif
  4              where $i/user="J.DURAND"
  5              return $i/date'
  6             passing object_value
  7             returning content
  8           )
  9           as date
10         ) DATE_MODIF
11  from data_xml;
DATE_MODIF
25/04/2013