Re: Performance on writable views

Enrico Weigelt wrote:
> I'm often using writable views as interfaces to clients, so
> they only see "virtual" objects and never have to cope with
> the actual storage, ie. to give some client an totally
> denormalized view of certain things, containing only those
> information required for certain kind of operations.
>
> This method is nice for creating easy and robust client
> interfaces - internal schema changes are not visible to
> the client. In situations when many, many clients - often
> coded/maintained by different people - have to access an
> database which is still under development (typical for
> many inhouse applications), it helps to circument interface
> instabilities.
>
> Now I've got the strange feeling that this makes updates
> slow, since it always has to run the whole view query to
> fetch an record to be updated (ie. to get OLD.*).

There is some overhead in rewriting the query, but it shouldn't be
significantly slower than issuing the statements behind the view
directly. I wouldn't worry about it, unless you have concrete evidence
that it's causing problems.

--
  Heikki Linnakangas
  EnterpriseDB   http://www.enterprisedb.com