Re: pytanie o operatory porównania

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#183519

From: Filip Rembiałkowski
Date: Tue, 21 Jul 2009 08:34

46 lines
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On 20 Lip, 20:19, hubert depesz lubaczewski <dep...@depesz.com> wrote:
> On 2009-07-20, Filip Rembiałkowski <plk.zu...@gmail.com> wrote:
>
>
>
> > trzeba uważać z liczbami. w mysql sprawa jest śliska:
> > mysql> select 123 > 'ala';
> > +-------------+
> >| 123 > 'ala' |
> > +-------------+
> >|           1 |
> > +-------------+
> > 1 row in set, 1 warning (0,00 sec)
>
> > mysql> select  'ala' < 123;
> > +-------------+
> >| 'ala' < 123 |
> > +-------------+
> >|           1 |
> > +-------------+
> > 1 row in set, 1 warning (0,00 sec)
> > (mysql 5.0.
> > jak widać zwraca zupełnie sprzeczne wyniki dla pozornie takich samych
> > porównań.
>
> ekhem? gdzie to sprzeczność wyników?
>
echhhh zakręciłem się - nie o to mi chodziło....

mysql> select  'ala' < 123;
+-------------+
| 'ala' < 123 |
+-------------+
|           1 |
+-------------+
1 row in set, 1 warning (0,00 sec)

(ten 1 warning to pewnie ostrzeżenie o rzutowaniu)

mysql> select  'ala' < '123';
+---------------+
| 'ala' < '123' |
+---------------+
|             0 |
+---------------+
1 row in set (0,00 sec)

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From: Filip Rembiałkowski <plk.zuber@gmail.com>
Newsgroups: pl.comp.bazy-danych
Subject: Re: pytanie o operatory porównania
Date: Tue, 21 Jul 2009 01:34:58 -0700 (PDT)
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