hi,
The query i had posted earlier-
select distinct mh.code,rubrica from multimedia_header mh, members_log ml
where ml.member = 43
and mh.date > ml.date
still doesnt execute as i want...The above query runs but returns a
resultset which includes a record within the same hour.. i.e. to say that if
there is a difference of a day or more, the query runs fine but doesnt take
into account the hours and minutes.. how can I rectify this??
thnx,
sands
-----Original Message-----
From: Jeremy Zawodny [mailto:jzawodn@stripped]
Sent: quarta-feira, 8 de Maio de 2002 6:25
To: David McInnis
Cc: Sandeep Murphy; mysql@stripped
Subject: Re: dates
On Tue, May 07, 2002 at 01:10:46PM -0700, David McInnis wrote:
>
> I would suggest doing "member = 43 and mh.date > ml.date" since
> there could potentially be more records that meet the second
> criteria. I always try to optimize my queries to narrow my
> recordset as small as possible before I apply any other criteria.
That's good for human readability, but a good optimizer shouldn't
care.
> That said, MySQL may do this sort of optimization internally. (I
> would be curious to know from more seasoned MySQL gurus if this is
> the case).
It is the case. Next time you're messing with one of your queries,
run it through "EXPLAIN <query>" and see what is says. Then change
the order of stuff in the WHERE clause and try again. You should see
the same output. If you don't, report it as a bug. :-)
Jeremy
--
Jeremy D. Zawodny, <jzawodn@stripped>
Technical Yahoo - Yahoo Finance
Desk: (408) 349-7878 Fax: (408) 349-5454 Cell: (408) 685-5936
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