From: Aaron Bono <postgresql@aranya.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: phillips@weatherbeeta.com.au
Cc: pgsql-sql@postgresql.org
Subject: Re: COPY to table with array columns (Longish)
Date: Mon, 12 Jun 2006 21:58:13 -0500
Message-ID: <bf05e51c0606121958i54a7833bt76bb8756dd41aec1@mail.gmail.com> (raw)
In-Reply-To: <14241.1150158614@sss.pgh.pa.us>
References: <003901c68e7a$4833dab0$9b0014ac@ITPhil>
<14241.1150158614@sss.pgh.pa.us>
I agree with Tom. Personally I cannot think of a time I would use an array
column over a child table. Maybe someone can enlighten me on when an array
column would be a good choice.
What language are you using to do the export if I may ask?
-Aaron
On 6/12/06, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
> "Phillip Smith" <phillips@weatherbeeta.com.au> writes:
> > The whole sys file is variable length records like this - they range =
> > from 1
> > to over 17,000 fields per record.
>
> 17000? I think you really need to rethink your schema. While you could
> theoretically drop 17000 elements into a PG array column, you wouldn't
> like the performance --- it'd be almost unsearchable for instance.
>
> I'd think about two tables, one with a single row for each SYS record
> from the original, and one with one row for each detail item (the
> invoice numbers in this case). With suitable indexes and a foreign key
> constraint, this will perform a lot better than an array-based
> translation.
>
> And no, in neither case will you be able to import that file without
> massaging it first.
>
> regards, tom lane
>
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To: pgsql-sql@postgresql.org
Cc: postgresql@aranya.com, tgl@sss.pgh.pa.us, phillips@weatherbeeta.com.au
Subject: Re: COPY to table with array columns (Longish)
In-Reply-To: <bf05e51c0606121958i54a7833bt76bb8756dd41aec1@mail.gmail.com>
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