Creating an Updateable View with Key Preservable Tables

Question

Hello everyone,
I'm trying to create a view of two tables that I have in order to perform an instead of trigger on said view. The table structures for the tables I am using are as follows:
Project Tasks Table
TASK_ID  (Primary Key)
TASK_NAME
TASK_DUE_DATE
Task Assignments Table
ASSIGNMENT_ID (Primary Key)
TASK_ID (Foreign Key)
USER_ID
ASSET_ID
Given that, I'd like to create a view of a left outer join of the tables, so that every task is shown, regardless of whether or not it is assigned to someone. I've successfully created the view, which can be seen here:
select
P.TASK_ID,
P.TASK_DUE_DATE,
P.TASK_NAME,
TA.ASSET_ID,
TA.USER_ID
from PROJECT_TASKS P
     left outer join PROJECT_TASK_ASSIGNMENTS TA
    on P.PROJECT_TASKS.TASK_ID = TA.PROJECT_TASK_ASSIGNMENTS.TASK_ID;
I have also created a trigger on this view, to update both tables on an insert to the view. However, I cannot execute the trigger as when I check if the columns are user updateable, it shows NO for all of them. Is there any way I can create a view on these tables that allows for every column to be UPDATEABLE, INSERTABLE and DELETABLE?

Answer 1

Hi,
If you're writing an INSTEAD OF trigger, then it doesn't matter if anything in the view is updateable, insertable, deleteable or whatnotable.  Do all DML operations directly on the base tables.
If you have problems, then post a complete test script that the peope who want to help you can run to re-create the problem and test their ideas.  Include CREATE TABLE and INSERT statements for you base tabels, the CREATE VIEW statement (if not exactly what you already posted), your best attempt at a CREATE TRIGGER statement, and some code that tests it.  Explain what results you want from that test (that is, what the tables should contain after it finishes.)
Start small and take baby steps.  Start with a trigger that, say, only DELETEs.  When we get that working, then we can change iot to handle INSERTs.