mnesia query

Sebastian Bello <>
Wed Aug 3 22:03:16 CEST 2005


No ideas?
    Sebastian-
----- Original Message -----
From: "Sebastian Bello" <>
To: <>
Sent: Friday, July 22, 2005 2:04 PM
Subject: Re: mnesia query


> I've done some test with indexes and am a bit confused.
> I've ran the same query using select, index_read and QLC and performance
> seems to follow that same order(faster to slower). I noted that
performance
> depedends on the number of records associated to the value of the index
> searched. There's surely something I'm missing here. My questions would
be:
> 1. shouldn't performance be better for index_read and QLC than select
(since
> an index is beeing used)?
> 2. when using QLC, should indexes be used explicitly (or just write a
normal
> list comprehension query)?
> 3. depending on 2, how can I use two indexes with QLC?
> 4. just to be sure, should a search through two indexes be always faster
> than using just one?
>
> I saw some old questions regarding this point, but didn't get a clear idea
> about it.
> Thanks,
>     Sebastian-
>
> ----- Original Message -----
> From: "Ulf Wiger" <>
> To: "Sebastian Bello" <>;
<>
> Sent: Sunday, July 17, 2005 11:19 AM
> Subject: Re: mnesia query
>
>
> > Den 2005-07-17 15:26:43 skrev Sebastian Bello <>:
> >
> > > But is it possible to use mnesia:index_match_object() with two
indexes?
> > >     Sebastian-
> >
> > No. You specify exactly _one_ index that index_match_object() is to use.
> >
> > /Uffe
> >
> >
>
>
>





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