Thread: Using constraint exclusion with 2 floats

Hi everyone,
Is there an easy way (that I maybe missed) to use constraint exclusion with 2 floats ?
Must I find an extension the temporal extension which create a new type with 2 timestamp or can I usethe && operator with 2 fields ?

Thank you

On Wed, Oct 12, 2011 at 10:16 AM, Julien Rouhaud <rjuju123@gmail.com> wrote:
> Hi everyone,
> Is there an easy way (that I maybe missed) to use constraint exclusion with
> 2 floats ?
> Must I find an extension the temporal extension which create a new type with
> 2 timestamp or can I usethe && operator with 2 fields ?

There's nothing in constraint exclusion that depends upon specific datatypes.

Let us know if you find a problem with floats.

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

Thank you for your answer.

I'm sorry I really didn't explained well my problem :/

For example if I have a table test like this :
CREATE TABLE test (min real not null, max real not null, desc character varying not null);

and I want a constraint exclusion to make sure the range min/max doens't overlap

I can't write ALTER TABLE test add constraint test_exclude EXCLUDE USING btree ((min,max) WITH &&)

I saw the extension temporal gives a new type PERIOD and has operators like &&, but only for timestamp, so I'm wondering if I must code something something similar or if there's is an easier way

On Wed, Oct 12, 2011 at 10:40 PM, Julien Rouhaud <rjuju123@gmail.com> wrote:
> Thank you for your answer.
>
> I'm sorry I really didn't explained well my problem :/
>
> For example if I have a table test like this :
> CREATE TABLE test (min real not null, max real not null, desc character
> varying not null);
>
> and I want a constraint exclusion to make sure the range min/max doens't
> overlap
>
> I can't write ALTER TABLE test add constraint test_exclude EXCLUDE USING
> btree ((min,max) WITH &&)
>
> I saw the extension temporal gives a new type PERIOD and has operators like
> &&, but only for timestamp, so I'm wondering if I must code something
> something similar or if there's is an easier way

You've confused "exclusion constraints" with "constraint exclusion",
which does seem easy to do.

"Exclusion constraints" are not limited to a single datatype either,
so you should be able to find a solution.

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