Re: PostgreSQL Inheritance and column mapping

On 03/10/2014 05:54, Jim Nasby wrote:
> On 10/2/14, 9:00 AM, Tom Lane wrote:
>> Achilleas Mantzios <achill@matrix.gatewaynet.com> writes:
>>> Was there ever any discussion.thought about being able to follow a non-strict by name
>>> column mapping between inherited tables and father tables?
>> No.  You could use a view with UNION ALL perhaps.
> FWIW, I've had some less than stellar results with that (admittedly, back on 8.4).
>
> The other thing you could do is something like:
>
> ALTER TABLE invoice_document RENAME TO invoice_document_raw;
> ALTER TABLE invoice_document_raw RENAME invoice_no TO doc_no;
> CREATE VIEW invoice_document AS
>     SELECT ...
>         , doc_no AS invoice_no
>         , ...
>     FROM invoice_document_raw
> ;
>
> If you make that view writable then no one needs to know that you renamed the column in the underlying table.

That is a brilliant idea, thank you!
One problem is that the tables are a part of a 100-node replication system base on a heavily hacked
version of DBMirror, over a non-TCPIP Satellite network. That would require rewriting rules
and deploying this across the remote nodes.
I would be afraid to run the ALTER TABLE ... RENAME TO command in this system.
So, we could just bite the bullet and get our team rewrite all programs.

--
Achilleas Mantzios
Head of IT DEV
IT DEPT
Dynacom Tankers Mgmt