Cursor loops; How to perform something at start/end of loop 1 time only?

I've got the following in one of my Oracle procedures, I'm using it to generate XML

  -- v_client_addons is set to '' to avoid null error
  OPEN C_CLIENT_ADDONS;
  LOOP
    FETCH C_CLIENT_ADDONS INTO CLIENT_ADDONS;
    EXIT WHEN C_CLIENT_ADDONS%NOTFOUND;
    BEGIN
      v_client_addons := v_client_addons || CLIENT_ADDONS.XML_DATA;
    END;
  END LOOP;
  CLOSE C_CLIENT_ADDONS;

  -- Do something later with v_client_addons

The loop should go through my cursor and pick out all of the XML values to display, such as :

<add-on name="some addon"/>
<add-on name="another addon"/>

What I would like to achieve is to have an XML start/end tag inside this loop, so I would have the following output

<addons>
   <add-on name="some addon"/>
   <add-on name="another addon"/>
</addons>

How can I d开发者_开发百科o this without having the <addons> tag after every line? If there are no addons in the cursor (cursor is empty), then I would like to skip this part enitrely

check the length of v_client_addons. If it is greater than 0, you actually appened something. Then create you parent tag with its children, else just ignore it.

How about using SQL to generate the entire XML, instead of looping over a cursor?

SELECT XMLELEMENT("addons", XMLAGG(C.XML_DATA)) INTO v_client_addons 
FROM CLIENT_ADDON_TABLE C;