On 21 Oct 2009, at 11:34pm, Sylvain Pointeau wrote:
> if your "book" contains all lines (a,b,c,t,d)and you create an index
> on
> (a,b,c,t)
I assume you meant to add ',d'in there.
> then your index is as fat as your book, isn't it?
Yes. And it still isn't as useful for any SELECT that doesn
On Thu, Oct 22, 2009 at 12:34:26AM +0200, Sylvain Pointeau wrote:
> if your "book" contains all lines (a,b,c,t,d)and you create an index on
> (a,b,c,t)
>
> then your index is as fat as your book, isn't it?
Depends on the size of d.
Also, if you add a constraint declaring t, a, b, and c (you want
if your "book" contains all lines (a,b,c,t,d)and you create an index on
(a,b,c,t)
then your index is as fat as your book, isn't it?
cheers,
Sylvain
On Wed, Oct 21, 2009 at 11:52 PM, Simon Slavin wrote:
>
> On 21 Oct 2009, at 9:19pm, Sylvain Pointeau wrote:
>
> > Thank you for your answers.
> >
On 21 Oct 2009, at 9:19pm, Sylvain Pointeau wrote:
> Thank you for your answers.
> knowing that I have a table T (a,b,c,d,t)
> where d is a value
> a,b,c some dimensions
> and t the time
>
> where I need to make a subset with a "group by" like
>
> select a,b,c,sum(d)
> from T
> where t>x1 and t g
the individual transactions you avoid, which makes a huge
> difference.
>
> John
>
> -Original Message-
> From: sqlite-users-boun...@sqlite.org
> [mailto:sqlite-users-boun...@sqlite.org] On Behalf Of Pavel Ivanov
> Sent: Tuesday, October 20, 2009 2:47 PM
> To: General Discussio
you avoid, which makes a huge
difference.
John
-Original Message-
From: sqlite-users-boun...@sqlite.org
[mailto:sqlite-users-boun...@sqlite.org] On Behalf Of Pavel Ivanov
Sent: Tuesday, October 20, 2009 2:47 PM
To: General Discussion of SQLite Database
Subject: Re: [sqlite] index for a g
e more btree than that, increase the size, or split across
> several transactions.
>
> John
>
> -Original Message-
> From: sqlite-users-boun...@sqlite.org
> [mailto:sqlite-users-boun...@sqlite.org] On Behalf Of Pavel Ivanov
> Sent: Tuesday, October 20, 2009 7:35 AM
&
Sent: Tuesday, October 20, 2009 7:35 AM
To: General Discussion of SQLite Database
Subject: Re: [sqlite] index for a group by
> please could you let me know which index could be better or faster?
For this particular query index on (t,a,b,c) or even on (t,a,b,c,d)
would be better and cause the q
> please could you let me know which index could be better or faster?
For this particular query index on (t,a,b,c) or even on (t,a,b,c,d)
would be better and cause the query to execute faster (of course if by
conditions t>x1 and t also do you know by chance how to speed up the index creation?
The
hello,
I have a table T (a,b,c,d,t)
where c is a value
a,b,c some dimensions
and t the time
I need to make a subset with a "group by"
like
select a,b,c,sum(d)
from T
where t>x1 and thttp://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
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