Re: textarray option for file FDW

From: Andrew Dunstan <andrew(at)dunslane(dot)net>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: textarray option for file FDW
Date: 2011-01-15 18:07:59
Message-ID: 4D31E27F.3030600@dunslane.net
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

On 01/15/2011 12:44 PM, Tom Lane wrote:
> Andrew Dunstan<andrew(at)dunslane(dot)net> writes:
>> ... So now I'd like to add a
>> new option to it: "textarray". This option would require that the
>> foreign table have exactly one field, of type text[], and would compose
>> all the field strings read from the file for each record into the array
>> (however many there are).
> Why is this a good thing? It seems like it would accomplish little
> except to defeat the SQL type system entirely.
>
>

We have discussed previously allowing this sort of thing. It's not a new
proposal at all.

My use case is that I have a customer who reads in data like this (using
my patch to allow ragged CSV input, which you previously objected to)
and then performs a sophisticated battery of validity tests on the data
before loading it into its final destination. To do that their
requirement is that we not error out on reading the data, so we load the
data into a table that is all text fields.

In fact, having COPY read in a text array is *your* suggestion:
<http://archives.postgresql.org/pgsql-hackers/2009-09/msg00547.php>.
This is simply a proposal to implement that via FDW, which makes it easy
to avoid any syntax issues.

cheers

andrew

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Magnus Hagander 2011-01-15 18:10:48 pg_basebackup for streaming base backups
Previous Message Noah Misch 2011-01-15 17:53:55 Re: patch: fix performance problems with repated decomprimation of varlena values in plpgsql