Re: Use of the LIMIT clause ?

From: Spy <spy(at)joystick(dot)fr>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, pgsql-admin(at)postgresql(dot)org
Subject: Re: Use of the LIMIT clause ?
Date: 2001-03-13 01:31:06
Message-ID: 3AAD785A.2DAEDCE@joystick.fr
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Tom Lane a écrit :
>
> Richard Bayet <bayet(at)enseirb(dot)fr> writes:
> > I did knew about this, but the author goes further about the "limit
> > N,P", which allows someone to get only results between the Nth and Pth
> > lines of the whole result...
>
> Is that actually how MySQL interprets two parameters? We treat them
> as count and offset respectively, which definition I thought was the
> same as MySQL's.

Well, it looks like the web site I read the piece of information from
was mistaking...
But MySQL's syntax is different, as found on
http://www.mysql.com/doc/S/E/SELECT.html :
"SELECT [STRAIGHT_JOIN] [SQL_SMALL_RESULT] [SQL_BIG_RESULT]
[SQL_BUFFER_RESULT]
[...]
[LIMIT [offset,] rows]"

>
> > I tried this with psql, but couldn't get anything but parse errors.
>
> Works for me:
>
> regression=# select unique1 from tenk1 limit 10;
> unique1
> ---------
> 8800
> 1891
> 3420
> 9850
> 7164
> 8009
> 5057
> 6701
> 4321
> 3043
> (10 rows)
>
> regression=# select unique1 from tenk1 limit 3,5;
> unique1
> ---------
> 8009
> 5057
> 6701
> (3 rows)
>
> regression=#
>
> What PG version are you running?

I'm using v.7.0.2, and the above examples worked for me :)
When I tried using the LIMIT clause the first times, to obtain the same
results, I would have tried "select unique1 from tenk1 limit 5,8", ie
"limit start, stop"
Then I would have got :
unique1
---------
4321
3043
(2 rows)

What I tried and didn't work was the same as "select unique1 from tenk1
limit 5,10" (in my mind, getting the five last rows)...

Thanks for your help

>
> regards, tom lane
>
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