Thanks Kevin,
This one initially added about 10sec to the run but I added a HASH
index on the alias field and its now about 5 sec average runtime, a net
improvement.
Shawn
On Sun, 02 Sep 2007 10:49:09 -0500 "Kevin Grittner"
<Kevin.Grittner@xxxxxxxxxxxx> wrote:
> >>> On Sat, Sep 1, 2007 at 12:29 PM, in message
> <20070901102947.0c0a50a3@xxxxxxxxxxxxxxxxxxxxxx>, Shawn
> <postgres@xxxxxxxxxxxxxxx> wrote:
> > update shawns_data set alias = null;
> > Even after VACUUM this simple line takes 35 sec to complete.
>
> Would any rows already have a null alias when you run this?
>
> If so, try adding 'where alias is not null' to the query.
>
> -Kevin
>
>
>
>
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