Re: 7.3.4 on Linux: UPDATE .. foo=foo+1 degrades massivly over time

On Wed, Apr 21, 2004 at 14:55:51 -0700,
  Dann Corbit <DCorbit@connx.com> wrote:
>
> Shouldn't the Database server be the entity that decides when vacuum is
> needed?

At least in simple cases it should. That is what the auto vacuum project
is trying to do.

> Also, I should be able to do an update on every row in a database table
> without causing severe problems.  Every other database system I know of
> does not have this problem.

You can do this in postgres without causing too much trouble.

The problem at the beginning of this thread was caused by updating
a one row table thousands of times which can cause problems if
you don't vacuum.

> If I have a million row table with a column called is_current, and I do
> this:
> UPDATE tname SET is_current = 0;
> Horrible things happen.

Like what? At worst you will double the disk space used by this table.
That isn't great, but it surely isn't horrible under normal circumstances.

> Just an idea:
> Why not recognize that more rows will be modified than the row setting
> can support and actually break the command into batches internally?

This doesn't make sense. There is no limit on the number of rows that
can be modified at once.