XMLAgg function

Question

Hi, I try to generate a XML with SQL. My sql sentence is following:
SELECT xmlelement("RAIZ", xmlelement("DATOS",
                    XMLAgg( xmlelement("GRUPO",
                    xmlattributes( G.VDESCRIPCION AS "NOMBRE" ),
                    XMLAgg( xmlelement("OPCION",
                    xmlattributes(O.VDESCRIPCION AS "NOMBRE", O.VFUNCION AS "URLO"),
                         XMLAgg(xmlelement("SUB",xmlattributes(S.VDESCRIPCION AS "NOMBRE", S.VFUNCION AS "URLO") )))) )     )) )
FROM AX_MENUPUNTO O, AX_MENUPUNTO S,
( SELECT *
FROM AX_MENUPUNTO
WHERE VCODPUNMENUPADRE IS NULL ) G
WHERE G.VCODPUNMENU = O.VCODPUNMENUPADRE (+)
AND O.VCODPUNMENU = S.VCODPUNMENUPADRE (+)
GROUP BY G.VCODPUNMENU, O.VCODPUNMENU, S.VCODPUNMENU,
G.VDESCRIPCION, O.VDESCRIPCION, S.VDESCRIPCION
When I post the XMLAgg function IN BOLD, appear me a message that says that is enougth deep level for XMLAgg.
Can anybody help me please??
Regards.

Answer 1

Hi,
This is my suggestion - use PL/SQL to slowly build up your XML Document. It's neat & helps to logically build your solution. Here's a sample :-
CREATE OR REPLACE FUNCTION GET_XML_DOCUMENT
RETURN XMLTYPE
AS
     ln_xml_retval     XMLTYPE;
     ln_sql_code     NUMBER;
BEGIN
     BEGIN
     SELECT
          XMLAGG(
               XMLELEMENT(
                        "SUB",
                         XMLATTRIBUTES(
                                      S.VDESCRIPCION AS "NOMBRE",
                                      S.VFUNCION AS "URLO"
        INTO
          ln_xml_retval
     FROM
          AX_MENUPUNTO S;
     EXCEPTION
          WHEN OTHERS THEN
               ln_sql_code:=SQLCODE;
               SELECT XMLELEMENT(ERROR,ln_sql_code) INTO ln_xml_retval FROM DUAL;
               RETURN ln_xml_retval;
     END;
     RETURN ln_xml_retval;
END GET_XML_DOCUMENT;Now, I can use my function like this :-
SELECT GET_XML_DOCUMENT FROM DUAL;I inserted these values into the Table:-
INSERT INTO AX_MENUPUNTO VALUES( 'A','A','A','A' );
INSERT INTO AX_MENUPUNTO VALUES( 'B','B','B','B' );
INSERT INTO AX_MENUPUNTO VALUES( 'C','C','C','C' );
COMMIT;And, this is what I get :-
SQL> SET LONG 1000;
SQL> SELECT GET_XML_DOCUMENT FROM DUAL;
GET_XML_DOCUMENT
<SUB NOMBRE="A" URLO="A"></SUB><SUB NOMBRE="B" URLO="B"></SUB><SUB NOMBRE="C" UR
LO="C"></SUB>This way, you can work up bits of your logic and assemble them together. Youc an also resue some of the functions in other functions... ( I usually work with XML this way - again, it's my personal choice...)...
I am still trying out your big Select statement in my Function - I'll let you know if I find something interesting. You might want to try the same.....
Regards,
Sandeep