Re: [SQL] Plpgsql Language Feature?

Lists: pgsql-sql
From: David Hartwig <daveh(at)insightdist(dot)com>
To: pgsql-sql <pgsql-sql(at)postgreSQL(dot)org>
Subject: Plpgsql Language Feature?
Date: 1999-02-11 22:29:27
Message-ID: 36C359C7.60932427@insightdist.com
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Lists: pgsql-sql

In the context of a plpgsql script is a possible to access the number of
rows effected by an UPDATE or DELETE statement? It could be used to
simplify, and probably improve performance on, many scripts. I would
like to do something like:

update foo set bar = bar + new.amount where key = new.key;

if ROWS_UPDATED > 0 then
-- This would be less likely to occur
insert into foo (key, bar) values (new.key, new.bar);
end if;

Otherwise I must construct an additional SELECTstatement to see if the
row exists. Something like:

select 1 from foo where key = new.key;

if found then
update foo set bar = bar + new.amount where key = new.key;
else
insert into foo (key, bar) values (new.key, new.bar);
end if;

Might this be a worth while feature if it does not now exist?

TIA.


From: jwieck(at)debis(dot)com (Jan Wieck)
To: daveh(at)insightdist(dot)com (David Hartwig)
Cc: pgsql-sql(at)postgreSQL(dot)org
Subject: Re: [SQL] Plpgsql Language Feature?
Date: 1999-02-12 01:08:47
Message-ID: m10B768-000EBRC@orion.SAPserv.Hamburg.dsh.de
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Lists: pgsql-sql

> In the context of a plpgsql script is a possible to access the number of
> rows effected by an UPDATE or DELETE statement? It could be used to
> simplify, and probably improve performance on, many scripts. I would
> like to do something like:
>
> update foo set bar = bar + new.amount where key = new.key;
>
> if ROWS_UPDATED > 0 then
> -- This would be less likely to occur
> insert into foo (key, bar) values (new.key, new.bar);
> end if;

Yes, I think this would be a nice feature. Will take a look
if I can add it before v6.5 BETA starts.

Jan

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