The following example shows some ways to use abstract datatype methods in a SQL script, including:

• Initializing a new event message structure with the Initialize method

  Important: You must call the Initialize method before you can perform any further manipulation on a new WF_EVENT_T object.

• Initializing a CLOB locator

• Writing a text variable into a CLOB variable

• Setting the content attributes of the event message structure with the Content method

• Setting the address attributes of the event message structure with the Address method

The example code is from the script wfevtenq.sql, which enqueues an event message on a queue using an override agent. See: Wfevtenq.sql.

declare
l_overrideagent varchar2(30) := '&overrideagent';
l_overridesystem varchar2(30) := '&overridesystem';
l_fromagent varchar2(30) := '&fromagent';
l_fromsystem varchar2(30) := '&fromsystem';
l_toagent varchar2(30) := '&toagent';
l_tosystem varchar2(30) := '&tosystem';
l_eventname varchar2(100) := '&eventname';
l_eventkey varchar2(100) := '&eventkey';
l_msg varchar2(200) := '&message';
l_clob clob;
l_overrideagent_t wf_agent_t;
l_toagent_t wf_agent_t;
l_fromagent_t wf_agent_t;
l_event_t wf_event_t;

begin

  /*You must call wf_event_t.initialize before you can manipulate
    a new wf_event_t object.*/
  wf_event_t.initialize(l_event_t);
  l_overrideagent_t := wf_agent_t(l_overrideagent, l_overridesystem);
  l_toagent_t := wf_agent_t(l_toagent, l_tosystem);
  l_fromagent_t := wf_agent_t(l_fromagent, l_fromsystem);

  if l_msg is null then
    l_event_t.Content(l_eventname, l_eventkey, null);
  else
    dbms_lob.createtemporary(l_clob, FALSE, DBMS_LOB.CALL);
    dbms_lob.write(l_clob, length(l_msg), 1, l_msg);
    l_event_t.Content(l_eventname, l_eventkey, l_clob);
  end if;

  l_event_t.Address(l_fromagent_t, l_toagent_t, 50, sysdate);

  wf_event.enqueue(l_event_t, l_overrideagent_t);

end;