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Re: Explanation about for

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From "Frank Millman" <frank@chagford.com>
Subject Re: Explanation about for
Date Tue, 10 Jan 2012 15:39:14 +0200
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"???????? ??????" <nikos.kouras@gmail.com> wrote in message 
news:afd612b7-2366-40be-badf-13c97655f72d@o12g2000vbd.googlegroups.com...
>
> So that means that
>
> for host, hits, agent, date in dataset:
>
> is:
>
> for host, hits, agent, date in  (foo,7,IE6,1/1/11)
>
> and then:
>
> for host, hits, agent, date in  (bar,42,Firefox,2/2/10)
>
> and then:
>
> for host, hits, agent, date in  (baz,4,Chrome,3/3/09)
>
>
> So 'dataset' is one row at each time?
> but we said that 'dataset' represent the whole result set.
> So isnt it wrong iam substituting it with one line per time only?

No. 'for host, hits, agent, date in dataset:' is equivalent to -

for row in dataset:  # iterate over the cursor, return a single row (tuple) 
for each iteration
   host, hits, agent, date = row  # unpack the tuple and assign the elements 
to their own names

For the first iteration, row is the tuple ('foo', 7, 'IE6', '1/1/11')
For the next iteration, row is the tuple ('bar', 42, 'Firefox', '2/2/10')
For the next iteration, row is the tuple ('baz', 4, 'Chrome', '3/3/09')

The original line uses a python technique that combines these two lines into 
one.

HTH

Frank Millman

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Thread

Explanation about for Νικόλαος Κούρας <nikos.kouras@gmail.com> - 2012-01-09 15:23 -0800
  Re: Explanation about for Ian Kelly <ian.g.kelly@gmail.com> - 2012-01-09 16:42 -0700
  Re: Explanation about for Chris Rebert <clp2@rebertia.com> - 2012-01-09 15:58 -0800
  Re: Explanation about for Ian Kelly <ian.g.kelly@gmail.com> - 2012-01-09 18:11 -0700
    Re: Explanation about for Νικόλαος Κούρας <nikos.kouras@gmail.com> - 2012-01-10 01:02 -0800
      Re: Explanation about for Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2012-01-10 11:57 +0100
        Re: Explanation about for Νικόλαος Κούρας <nikos.kouras@gmail.com> - 2012-01-10 03:38 -0800
          Re: Explanation about for Jussi Piitulainen <jpiitula@ling.helsinki.fi> - 2012-01-10 14:52 +0200
        Re: Explanation about for Νικόλαος Κούρας <nikos.kouras@gmail.com> - 2012-01-10 03:37 -0800
          Re: Explanation about for "Frank Millman" <frank@chagford.com> - 2012-01-10 15:39 +0200
          Re: Explanation about for Thomas Rachel <nutznetz-0c1b6768-bfa9-48d5-a470-7603bd3aa915@spamschutz.glglgl.de> - 2012-01-10 16:22 +0100
          Re: Explanation about for RainyDay <andrei.avk@gmail.com> - 2012-01-11 14:39 -0800
      Re: Explanation about for  Nick Dokos <nicholas.dokos@hp.com> - 2012-01-10 10:24 -0500
        Re: Explanation about for Νικόλαος Κούρας <nikos.kouras@gmail.com> - 2012-01-11 14:50 -0800

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