Is it possible... - Mailing list pgsql-general

From Uwe C. Schroeder
Subject Is it possible...
Date
Msg-id 200408240847.43584.uwe@oss4u.com
Whole thread Raw
Responses Re: Is it possible...
Re: Is it possible...
List pgsql-general
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1


Hi all,

I wasn't able to get a usable answer by googling: Is there a way to create a
view on a table that converts rows to columns ?
Example:
I have a table

create table blah (
    id int4 serial,
    parentid int4,
    pname varchar(64),
    pvalue varchar(128)
);

which is basically a classic key/value pair. Parentid is a field defining that
certain rows belong to the same entity, i.e.:

1  1  'firstkey' 'firstvalue'
2  1  'secondkey' 'secondvalue'
...
...
10 2 'firstkey' 'firstvalue'
...

All the "parents" have the same set of keys - guaranteed.
I'd need to convert this into a table which has the  keynames as columns and
one row per "parentid", i.e.:

parentid firstkey     secondkey
1            firstvalue  secondvalue
2            firstvalue  secondvalue


I hate the idea of writing code that really creates and fills a table,
particularly since the original table has a lot of rows.

Is the above doable with a view?
Any pointers will be appreciated.

Thanks

    UC

- --
Open Source Solutions 4U, LLC    2570 Fleetwood Drive
Phone:  +1 650 872 2425        San Bruno, CA 94066
Cell:   +1 650 302 2405        United States
Fax:    +1 650 872 2417
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.3 (GNU/Linux)

iD8DBQFBK2MfjqGXBvRToM4RAt/dAKCcBaDVMvfP9fIJDy6qFh8euRfnJwCfY8HH
hqjmfHNjzTjZ71jdhjv4cIU=
=TfAU
-----END PGP SIGNATURE-----


pgsql-general by date:

Previous
From: mike
Date:
Subject: Re: Invalid input for integer on VIEW
Next
From: Gaetano Mendola
Date:
Subject: Re: No connection to a PG 8.0 Beta 1 win32 server