Обсуждение: CONSTRAINT name With Domain As Check

   I define a table, Permits, that includes a column for type.

   Permit_Type is a domain with permissible names:

CREATE DOMAIN Permit_Type
   as TEXT
   CHECK (value in ('Environmental', 'Health', 'Safety', 'Occupancy'));

   Can I name that domain check within the Permits table as follows?

CREATE TABLE Permits (
   ...
   type Permit_Type
     CONSTRAINT invalid_permit_type
   ...
);

   If not, does the constraint name belong in the domain definition?

Rich

--
Richard B. Shepard, Ph.D.               |    The Environmental Permitting
Applied Ecosystem Services, Inc.        |          Accelerator(TM)
<http://www.appl-ecosys.com>     Voice: 503-667-4517      Fax: 503-667-8863

Rich Shepard <rshepard@appl-ecosys.com> writes:
>    I define a table, Permits, that includes a column for type.
>    Permit_Type is a domain with permissible names:

> CREATE DOMAIN Permit_Type
>    as TEXT
>    CHECK (value in ('Environmental', 'Health', 'Safety', 'Occupancy'));

>    Can I name that domain check within the Permits table as follows?

> CREATE TABLE Permits (
>    ...
>    type Permit_Type
>      CONSTRAINT invalid_permit_type
>    ...
> );

Um, what are you trying to do that's different from declaring a column
of the table as being of type Permit_Type?

            regards, tom lane

On Sun, 29 Apr 2007, Tom Lane wrote:

> Um, what are you trying to do that's different from declaring a column of
> the table as being of type Permit_Type?

Tom,

   Nothing. After further consideration I decided that the domain was
unnecessary and the table column with a CHECK() constraint the more
appropriate approach.

Thanks,

Rich

--
Richard B. Shepard, Ph.D.               |    The Environmental Permitting
Applied Ecosystem Services, Inc.        |          Accelerator(TM)
<http://www.appl-ecosys.com>     Voice: 503-667-4517      Fax: 503-667-8863