Re: Fwd: Re: Can I search for an array in csf? - Mailing list pgsql-sql

On Mon, 21 Oct 2002, Vernon Wu wrote:

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>
>
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> Hi, Richard,
>
> Thanks for your response and see below.
>
> 10/21/2002 3:13:57 AM, Richard Huxton <dev@archonet.com> wrote:
>
> >On Friday 18 Oct 2002 1:58 pm, Vernon Wu wrote:
> >> One field of a table stores an array of characters in a string fromat as
> >> "a,b,c,d". Is anyway to apply a select statement without using stored
> >> procedure?
> >>
> >> Thanks for your input.
> >
> >Not really,  and I can't think any way of accessing an index on this either.
> >Are you sure you wanted the characters stored this way? Even if the overhead
> >of a separate table isn't woth it, you might want to look into arrays and the
> >intarray stuff in contrib/
> >
>
> The reason I use this format for an array is that the array is dynamic. I have quite few cases of this type of
situation.The
 
> maximize length in some cases is known, is unknown in others. I have learnt the comment separated format is one way
> to solve the problem. Someone also suggested to store the array as an object. I am not sure whether it works or not.
> The application is written in Java, by the way.
>
> I have taken a look at intarray by searching on the postgres.org web site as well as in google. (I use cypwin and
unable
> to find the contrib directory). My impression is it isn't a standard SQL data type. And its element is integer only.
>
> It is my first time doing DB table design. Any helps will be gracfully appreciated.

Well some comments, since i have done a lot of work with
arrays, postgresql and java.

Arrays are supported by the postgresql jdbc driver just fine.
Arrays can be of any valid builtin or user defined type.
Postgresql Arrays along with intarray package are ideal for
doing small set manipulations, where the design fits
the natural model of your data (e.g. storing the factors
of a polynomial formula).
It would be nice if you had yourself a crash course on
relational db design.
Also i would advise you compiling and running postgres
on a unix system.
Note that in order to compile the intarray package
you need to have the sources installed.

>
> Thanks,
>
> Vernon
>
>
>
> >--
> >  Richard Huxton
> >
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