Unable to use the values returned by a PL/SQL stored procedure in a XSQL page

Question

Hi,
I've been messing around with XML and XSQL in particular. I was trying to write a xsql page to display a report with account totals...I have the following .xsql which calls a PL/SQL stored procedure :
<?xml version="1.0"?>
<xsql:query connection="pfcdm" xmlns:xsql="urn:oracle-xsql">
<xsql:set-session-param name="zasset_total" value="100">
<xsql:dml connection="pfcdm">
rraman.sp_vw_id(zasset_total,zinvm_total,zmkt_val);
</xsql:dml>
</xsql:set-session-param>
select 'Asset total is {@zasset_total}' as "ASSET_TOTAL" from dual
</xsql:query>
My procedure sp_vw_id returns the values that it should. But, I am not sure how to declare variables within a page, and to output the return values. There is very scanty documentation on the usage of <xsql:dml> or <xsql:ref-cursor-function>.
Any response would be greatly appreciated.
Thanks,
Raja

Answer 1

Here is the example from the Oracle9i (complete rewrite) of the XSQL Chapter in our Oracle documentation.
Question
I using <xsql:dml> to call a stored procedure which has one OUT parameter, but I was not able to see any results. The executed code results in the following statement:
<xsql-status action="xsql:dml" rows="0"/>
Answer
You cannot set parameter values by binding them in the position of OUT variables in this release using <xsql:dml>. Only IN parameters are supported for binding. You can create a wrapper procedure that constructs XML elements using the HTP package and then your XSQL page can invoke the wrapper procedure using <xsql:include-owa> instead.
For an example, suppose you had the following procedure:
CREATE OR REPLACE PROCEDURE addmult(arg1 NUMBER,
arg2 NUMBER,
sumval OUT NUMBER,
prodval OUT NUMBER) IS
BEGIN
sumval := arg1 + arg2;
prodval := arg1 * arg2;
END;You could write the following procedure to "wrap" it, taking all of the IN arguments that the procedure above expects, and then "encoding" the OUT values as a little XML datagram that you print to the OWA page buffer:
CREATE OR REPLACE PROCEDURE addmultwrapper(arg1 NUMBER, arg2 NUMBER) IS
sumval NUMBER;
prodval NUMBER;
xml VARCHAR2(2000);
BEGIN
-- Call the procedure with OUT values
addmult(arg1,arg2,sumval,prodval);
-- Then produce XML that encodes the OUT values
xml := '<addmult>'&#0124; &#0124;
'<sum>'&#0124; &#0124;sumval&#0124; &#0124;'</sum>'&#0124; &#0124;
'<product>'&#0124; &#0124;prodval&#0124; &#0124;'</product>'&#0124; &#0124;
'</addmult>';
-- Print the XML result to the OWA page buffer for return
HTP.P(xml);
END;This way, you can build an XSQL page like this that calls the wrapper procedure:
<page connection="demo" xmlns:xsql="urn:oracle-xsql">
<xsql:include-owa bind-params="arg1 arg2">
BEGIN addmultwrapper(?,?); END;
</xsql:include-owa>
</page>This allows a request like:
http://yourserver.com/addmult.xsql?arg1=30&arg2=45
to return an XML datagram that reflects the OUT values like this:
<page> <addmult><sum>75</sum><product>1350</product></addmult>
</page>