Re: VARIANT / ANYTYPE datatype - Mailing list pgsql-hackers

From Eric McKeeth
Subject Re: VARIANT / ANYTYPE datatype
Date
Msg-id BANLkTimpiFyf9kLDrfNFMpAXZVL5_4v80Q@mail.gmail.com
Whole thread Raw
In response to Re: VARIANT / ANYTYPE datatype  (Simon Riggs <simon@2ndQuadrant.com>)
List pgsql-hackers
On Tue, May 10, 2011 at 3:57 PM, Simon Riggs <simon@2ndquadrant.com> wrote:
On Wed, May 4, 2011 at 5:58 PM, Alvaro Herrera <alvherre@alvh.no-ip.org> wrote:

> A customer came to us with this request: a way to store "any" data in a
> column.  We've gone back and forth trying to determine reasonable
> implementation restrictions, safety and useful semantics for them.
> I note that this has been requested in the past:
> http://archives.postgresql.org/pgsql-general/2004-02/msg01266.php

I think its a reasonably common use case.

Would it be possible to do this with a "typed" hstore? Seems easier to
add something there than it would be to add the VARIANT type as
discussed here.


> both Oracle and MS-SQL have it

Do they? What types are they called?

--
 Simon Riggs                   http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services


MS SQL Server calls it's variant type 'sql_variant', but it's limited to a subset of the data types they support. Basically, it can store any numeric type, or any binary or text type with a constrained length. No timestamps, geometry, XML, user-defined types, etc. allowed. So it's not really as much of an "any value" type as it might look on the surface. Don't know any details of Oracle's implementation.

-Eric

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