XMLELEMENT/ XMLAGG functions

Question

Hi, I have a query to generate an XML output. I have the following questions:
1) I am typecasting the result from this query to a VARCHAR2 and I want to assign the output to a VARCHAR2 variable. Can you please help me with that. When I try to get this into a varchar variable, i get the following error:
declare
x varchar2(6000);
begin
SELECT CAST(xmlelement("itemMaster",
xmlelement("itemNumber",lpad(d.dept_i,3,0)||lpad(d.class_i,2,0)||lpad(d.item_i,4,0)),
xmlelement("itemDesc",NVL(d.ITEM_DESC_T,lpad(d.dept_i,3,0)||lpad(d.class_i,2,0)||lpad(d.item_i,4,0))),
xmlelement("paltSize",p1_test),
xmlelement("stdUOM",p1_test),
xmlelement("sellByDayQty",d.sell_by_day_q),
xmlelement("shflfUOM",p1_test),
xmlelement("minShflfDayQty",d.min_shflf_day_q),
xmlelement("itemCatgCode",NVL(d.dc_item_catg_c,'GM')),
xmlelement("strgTempZoneCode",NVL(d.strg_tmpr_zone_c,'01')),
xmlelement("retailAmt",retl_a),
xmlelement("expireDateFlag",NVL(d.expire_date_f,'N')),
xmlelement("randomWtFlag",NVL(d.rndm_wt_f,'N')),
xmlelement("wetFlag",NVL(d.wet_f,'N')),
xmlelement("areaCode",d.area_c),
xmlelement("vcpQty",d.vcp_q),
xmlelement("sspQty",d.ssp_q),
xmlelement("hndlTypeCode",d.hndl_type_c),
xmlelement("mstrPackTypeCode",d.mstr_pk_type_c),
xmlelement("mstrItemTypeCode",NVL(d.mstr_item_type_c,'00')),
xmlelement("sszCode",d.reg_ssz_excpt_c),
xmlelement("agriFlag",NVL(d.agrl_f,'N')),
xmlelement("itemRankCode",d.item_rank_c),
xmlelement("hazardFlag",NVL(d.hazd_mtrl_f,'N')),
xmlelement("createDate",to_char(d.create_d,'MM-DD-YYYY HH24:MI:SS')),
xmlelement("updateDate",to_char(d.modf_ts,'MM-DD-YYYY HH24:MI:SS')),
xmlelement("actvnDate",to_char(d.actvn_d,'MM-DD-YYYY HH24:MI:SS')),
xmlelement("organicCode",d.ognc_c),
xmlelement("lotCntlFlag",NVL(d.lot_cntl_f,'N')),
xmlelement("flammableFlag",NVL(d.flam_c,'N')),
xmlelement("recordMode",c.action_c),
xmlelement("areaType",p1_test),
xmlelement("uoms",
xmlelement("uom",
xmlelement("prodUOM",p1_test),
xmlelement("ratioDen",p1_test),
xmlelement("consldtRule",p1_test),
xmlelement("unitWtQty",NVL(d.unit_wt_q,1)),
xmlelement("vcpHeightQty",NVL(d.vcp_ht_q,1)),
xmlelement("vcpWidthQty",NVL(d.vcp_wth_q,1)),
xmlelement("vcpLengthQty",NVL(d.vcp_lgth_q,1)),
xmlelement("layerQty",p1_test)
(SELECT xmlelement("aliases",
xmlagg(xmlelement("upcCode",trunc(b.bar_code_i))
ORDER BY b.dept_i,b.class_i,b.item_i
FROM dc_item_bar_code b,
dc_item a
WHERE a.dept_i = b.dept_i
AND a.class_i = b.class_i
AND a.item_i = b.item_i
AND a.dept_i = c.dept_i
AND a.class_i = c.class_i
AND a.item_i = c.item_i
AS VARCHAR2(4000)
) INTO x
FROM dc_item d, item_wm_trigger_w c
WHERE d.dept_i = c.dept_i
AND d.class_i = c.class_i
AND d.item_i = c.item_i;
end;
ERROR at line 1:
ORA-06550: line 49, column 33:
PLS-00306: wrong number or types of arguments in call to 'XMLAGG'
ORA-06550: line 49, column 33:
PL/SQL: ORA-00904: "XMLAGG": invalid identifier
ORA-06550: line 4, column 1:
PL/SQL: SQL Statement ignored
When I run this query without the
declare
begin
select....
into...
end
construct, it's working perfectly fine.
Any help would be greatly appreciated.
Thanks,
Nitin

Answer 1

Is there a valid reason for putting the XMLTYPE result into a VARCHAR variable?
In most cases you can deal with your XML document by keeping it in the XMLTYPE. Should you need it in a "character" type format, then you are better using the .getClobVal() method on the XMLTYPE result to put the results into a CLOB as this will not have the size restriction of a VARCHAR.