Re: Year Only Date Column

[Michael Glaesemann <grzm(at)myrealbox(dot)com>]

On Nov 23, 2004, at 10:16 PM, Jeff Flowers wrote:

> I want to create a date column that contains only the year, such as
> YYYY. Can this done in PostgreSQL? I didn't see this listed in the
> handbook and right now, the only way I can see to do would be to create
> a numeric data field with zero scale and a precision of four.

You could do that, or create a domain that would restrict the date to 
only be, say, CCYY-01-01, which would represent the year. Something 
like:

test=# create domain date_year as date check (Date_trunc('year',value) 
= value);
CREATE DOMAIN
test=# select '1990-01-01'::date_year;
 date_year
------------
 1990-01-01
(1 row)

test=# select '1990-02-01'::date_year;
ERROR:  value for domain date_year violates check constraint 
"date_year_check"

It'll throw an error if you try to enter a date that isn't on January 1 
of that year.

Just an idea.

Michael Glaesemann
grzm myrealbox com