Re: SQL - Updates with joins

["Steve Richter" <stephenrichter@xxxxxxxxx>]

On 4/4/06, Hauser, Birgitta <Birgitta.Hauser@xxxxxxxxxxx> wrote:
> Hi Michael,
>
> joined logical files are not updateable, either.
>
> And you never should use a DDS-described logcial file in an SQL-statement.
> All SQL-statements where DDS described logical files are specified get
> rerouted to the old (classic) Query Engine (CQE).
> Not only the advantages of the new (SQL) Query Engine (SQE) cannot be
> exploited, this rerouting may cost up to 10-15% performance.
>
> With release V5R4M0 (or even with some PTFs in release V5R3M0) instead of
> triggers can be used to update SQL views that join several tables.
> Without registering an instead of trigger for the view, an update of the
> view will fail.
>
> In the following article you'll find a nice example:
> Perform the Impossible: Update a Multi-Table View using INSTEAD OF Triggers
> http://www.itjungle.com/fhg/fhg030806-story01.html
>

another helpful post Birgitta!  I did not know about INSTEAD OF
triggers.  Care to explain recursive queries in one or two sentences?
:)  ( just joking. my mind is not very receptive to sql syntax. )

thanks,

-Steve