How to update DB2 table with a join?

Question

I have two tables and I want to update by joining them. I am using DB2 V9.7.

ORDER_APPROVALS

ORDER_ID    CREATED_BY_ID   CREATED_BY         


        

Answer 1

I think you need to use a derived table to accomplish this:

update order_attributes
set value = (
  select
  created_by_name
  from(    
    select
    created_by_name,
    oa.order_id
    from
    order_approvals oa
    left outer join order_attributes ot
    on oa.order_id = ot.order_id
    AND OT.ATTRIBUTE_ID = 123 
    and OT.ORDER_ID in 
      (select ORDER_ID from ORDER_APPROVALS where PROCESS_DT is NULL)
    ) ORDERS
 WHERE orders.order_id = order_attributes.order_Id
    )