Thread: Materialized Views

Materialized Views

From
Michael Riess
Date:
Hi,

I've been reading an interesting article which compared different
database systems, focusing on materialized views. I was wondering how
the postgresql developers feel about this feature ... is it planned to
implement materialized views any time soon? They would greatly improve
both performance and readability (and thus maintainability) of my code.

In particular I'm interested in a view which materializes whenever
queried, and is invalidated as soon as underlying data is changed.

Mike

Re: Materialized Views

From
Frank Wiles
Date:
On Mon, 16 Jan 2006 15:36:53 +0100
Michael Riess <mlriess@gmx.de> wrote:

> Hi,
>
> I've been reading an interesting article which compared different
> database systems, focusing on materialized views. I was wondering how
> the postgresql developers feel about this feature ... is it planned
> to implement materialized views any time soon? They would greatly
> improve both performance and readability (and thus maintainability)
> of my code.
>
> In particular I'm interested in a view which materializes whenever
> queried, and is invalidated as soon as underlying data is changed.

  You can already build materialized views in PostgreSQL, but you
  end up doing the "heavy lifting" yourself with triggers. You put
  insert/update/delete triggers on the underlying tables of your
  view that "do the right thing" in your materialized view table.

  I wrote a blog entry about this recently,
  http://revsys.com/blog/archive/9, where I used a very simple
  materialized view to achieve the performance I needed. It has links
  to the relevant documentation you'll need however to build triggers
  for a more complex situation.

  Hope this helps!

 ---------------------------------
   Frank Wiles <frank@wiles.org>
   http://www.wiles.org
 ---------------------------------


Re: Materialized Views

From
Date:
hi mike

> In particular I'm interested in a view which materializes whenever
> queried, and is invalidated as soon as underlying data is changed.

from the german pgsql list earlier last week:

http://jonathangardner.net/PostgreSQL/materialized_views/matviews.html

this seems to be pretty much what you want (except you'll have to update
everything yourself). would be really nice if pgsql supports this "in-house"

cheers,
thomas



Re: Materialized Views

From
Michael Riess
Date:
Thanks!

Of course I know that I can build materialized views with triggers, but
so far I've avoided using triggers altogether ... I would really
appreciate something like "create view foo (select * from b) materialize
on query".

But I'll look into your blog entry, thanks again!

Mike
> On Mon, 16 Jan 2006 15:36:53 +0100
> Michael Riess <mlriess@gmx.de> wrote:
>
>> Hi,
>>
>> I've been reading an interesting article which compared different
>> database systems, focusing on materialized views. I was wondering how
>> the postgresql developers feel about this feature ... is it planned
>> to implement materialized views any time soon? They would greatly
>> improve both performance and readability (and thus maintainability)
>> of my code.
>>
>> In particular I'm interested in a view which materializes whenever
>> queried, and is invalidated as soon as underlying data is changed.
>
>   You can already build materialized views in PostgreSQL, but you
>   end up doing the "heavy lifting" yourself with triggers. You put
>   insert/update/delete triggers on the underlying tables of your
>   view that "do the right thing" in your materialized view table.
>
>   I wrote a blog entry about this recently,
>   http://revsys.com/blog/archive/9, where I used a very simple
>   materialized view to achieve the performance I needed. It has links
>   to the relevant documentation you'll need however to build triggers
>   for a more complex situation.
>
>   Hope this helps!
>
>  ---------------------------------
>    Frank Wiles <frank@wiles.org>
>    http://www.wiles.org
>  ---------------------------------
>
>
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