Re:

From: Jean-Luc Lachance <jllachan(at)nsd(dot)ca>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: Dan Langille <dan(at)langille(dot)org>, pgsql-sql(at)postgresql(dot)org
Subject: Re:
Date: 2003-09-29 14:04:08
Message-ID: 3F783BD8.48101D85@nsd.ca
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Wouldn't:

insert into r
select count(*)
from users
where date( lastlogin) > current_date - MaxDays * interval '' 1 day''
group by date( lastlogin);

be more efficient?

Tom Lane wrote:
>
> Dan Langille <dan(at)langille(dot)org> writes:
> > WHERE lastlogin between current_date - interval \''' ||
> > quote_literal(i - 1) || '' days\'
> > AND current_date - interval \''' ||
> > quote_literal(i) || '' days\''';
>
> IIRC, quote_literal() puts single quotes around its result. So you have
> too many quotes there. Given that you know i is an integer, you don't
> really need quote_literal for it. Actually, you don't need EXECUTE
> here at all. Why not just
>
> FOR i IN 1..MaxDays LOOP
> SELECT count(*)
> INTO r
> FROM users
> WHERE lastlogin between current_date - (i-1) * interval ''1 day''
> AND current_date - i * interval ''1 day'';
> RETURN NEXT r;
> END LOOP;
>
> regards, tom lane
>
> ---------------------------(end of broadcast)---------------------------
> TIP 7: don't forget to increase your free space map settings

In response to

  • Re: at 2003-09-28 19:45:22 from Tom Lane

Responses

  • Re: at 2003-09-29 14:03:19 from Dan Langille
  • Re: at 2003-09-29 21:19:04 from Dan Langille

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