Re: slow update

am Mon, dem 19.05.2008, um 23:56:27 -0600 mailte kevin kempter folgendes:
> Hi all;
>
> I have a query that does this:
>
> update tab_x set (inactive_dt, last_update_dt) =
> ((select run_dt from current_run_date), (select run_dt from
> current_run_date))
> where
> cust_id::text || loc_id::text in
> (select cust_id::text || loc_id::text from summary_tab);
>
>
> The current_run_date table has only 1 row in it
> the summary_tab table has 0 rows and the tab_x had 450,000 rows
>
> The update takes 45min even though there is no rows to update.
> I have a compound index (cust_id, loc_id) on both tables (summary_tab
> and tab_x)
>
> How can I speed this up ?

Please show us more details, for instance the data-types for cust_id and
loc_id. Wild guess: these columns are INT-Values and you have an Index.
Okay, but in the quere there is a CAST to TEXT -> Index not used.

Verfify this with EXPLAIN.

Andreas
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Andreas Kretschmer
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