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From:Graeme B. Davis Date:August 2 1999 5:13pm
Subject:Re: Any way to be faster?
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What would be the best way to determine the difference (hh:mm:ss) between
two datetimes?

I do something like
(unix_timestamp(issuestop)-unix_timestamp(issuestart))/3600 to get the
hours -- but would much rather get something like hh:mm:ss

any ideas?

thanks,
graeme

----- Original Message -----
From: Richard M. Neswold <rneswold@stripped>
To: Chai-Hup Chen <hup@stripped>
Cc: <mysql@stripped>
Sent: Thursday, June 17, 1999 1:04 PM
Subject: Re: Any way to be faster?


> On Thu, 17 Jun 1999, Chai-Hup Chen wrote:
>
> >   Any way to let unix_timestamp()-unix_timestamp(thetime) be faster?
> >   I have already index on thetime (timestamp(14)), but the response time
> > is still too slow. Any help will be appreciated. Thanks.
> >
> > select count(*) from Books;
> > +----------+
> > | count(*) |
> > +----------+
> > |   150749 |
> > +----------+
> > 1 row in set (0.00 sec)
> >
> > select count(*) from Books where
unix_timestamp()-unix_timestamp(thetime) > 1;
> > +----------+
> > | count(*) |
> > +----------+
> > |   150774 |
> > +----------+
> > 1 row in set (10.90 sec)
>
> Try to get the field-dependant portion out of the calculation. In other
> words, compare the field with a constant. What does this give you?
>
>    select count(*) from Books
>       where unix_timestamp() - 1 > unix_timestamp(thetime);
>
>   Rich
>
>  ========================================================================
>   Richard Neswold                                 |     rneswold@stripped
>   Home Page   'http://www.mcs.net/~rneswold/'     |
>   PGP Key     'finger rneswold@stripped'           |
>
>
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Thread
Any way to be faster?Chai-Hup Chen17 Jun
  • Re: Any way to be faster?Richard M. Neswold17 Jun
    • Re: Any way to be faster?Graeme B. Davis17 Jun
      • Re: Any way to be faster?Cooper Vertz17 Jun
    • Web-based queries on large-ish tablesJason Brooke6 Jul
      • Re: Web-based queries on large-ish tablesJames Rogers6 Jul
    • Re: Web-based queries on large-ish tablesMatt Duggan6 Jul
      • Re: Web-based queries on large-ish tablesJames Rogers6 Jul
    • Re: Web-based queries on large-ish tablesT├Ánu Samuel6 Jul
    • Re: Web-based queries on large-ish tablesMatt Duggan6 Jul