Triggers in Workspace Manager

Question

I've got some problems with the workspace manager and triggers in 10g:
If you have a trigger defined on a table and you version this table, ORACLE will create 3 "instead of"-triggers on the view representing the table.
The "content" of the trigger will be created in a wm$ procedure.
My question is: How can I change my trigger without unversioning the table?
As an example, consider the following two tables:
-- Create Data Table
CREATE TABLE MY_TABLE
     X_ID NUMBER(28) NOT NULL,
     V_TEXT VARCHAR2(200),
     V_COMMENT VARCHAR2(4000)
-- The Table's PK
ALTER TABLE MY_TABLE ADD CONSTRAINT PK_MY_TABLE
     PRIMARY KEY (X_ID)
USING INDEX;
-- Create Registry Table
CREATE TABLE MY_REGISTRY_TABLE
     X_ID NUMBER(28) NOT NULL,
     V_OLD_TEXT VARCHAR2(200),
     V_OLD_COMMENT VARCHAR2(4000),
     V_NEW_TEXT VARCHAR2(200),
     V_NEW_COMMENT VARCHAR2(4000),
     D_WHEN DATE NOT NULL
Now, we create a trigger that automatically registers the changes made on MY_TABLE:
-- Create Trigger
CREATE OR REPLACE TRIGGER TR_MY_TABLE
AFTER INSERT OR UPDATE OR DELETE ON MY_TABLE
FOR EACH ROW
BEGIN
     INSERT INTO MY_REGISTRY_TABLE(
          X_ID
          ,V_OLD_TEXT
          ,V_OLD_COMMENT
          ,V_NEW_TEXT
          ,V_NEW_COMMENT
          ,D_WHEN
     VALUES (
          NVL(:old.X_ID, :new.X_ID)
          ,:old.V_TEXT
          ,:old.V_COMMENT
          ,:new.V_TEXT
          ,:new.V_COMMENT
          ,sysdate
END TR_MY_TABLE;
Now, we decide to version MY_TABLE.
exec dbms_wm.enableversioning('MY_TABLE');
This turns MY_TABLE into 2 data tables and a collection of views.
The trigger has changed as well. The original trigger has disappeared, and there are 3 "INSTEAD OF"-triggers on the view MY_TABLE:
OVM_Delete_102
OVM_Insert_102
OVM_Update_102
These three triggers in the end call a system generated procedure:
wm$proc_udt_187
If I try to change this procedure, the system won't let me do that.
So, my question is, how can I change my trigger on MY_TABLE without unversioning the table?

Answer 1

Hi,
The 3 instead of triggers are created regardless of whether the table contained a user defined trigger or not. They are primarily used to implement the DML, but are used for other things as well as you noted. To change the definition of the trigger, you would need to use the Workspace Manager DDL procedure. See section 1.8 of the user guide. Essentially, you execute dbms_wm.beginDDL on the table, update the trigger on the <table_name>LTS table that is created (the trigger will have the original name that you gave it), then execute dbmswm.commitDDL.
Regards,
Ben