Re: Seeking Equivalent of InterBase Domain

From: DA Morgan <damorgan_at_psoug.org>
Date: Fri, 19 Jan 2007 19:42:54 -0800
Message-ID: <1169264570.640457@bubbleator.drizzle.com>

MRCarver wrote:
> Mark D Powell wrote:

>> MRCarver wrote:
>>>> Well, first off .. InterBase <> Oracle.  Don't try to reverse engineer
>>>> to work like something else.
>>> Not trying to reverse engineer, but simply trying to grasp Oracle's
>>> equivalent to Interbase's "DOMAIN".  A "DOMAIN", such as in Interbase or
>>> in CASE tools like Embarcedero's ERStudio, describe commonly used data
>>> types with certain constraints.  This way you define the constraint
>>> once, then simply bind it to a given field.
>>>> Second, maybe I'm missing something, but it looks like you are wanting
>>>> a boolean data type for a primary key column????  That would mean you
>>>> could only ever have two rows in the table.  I must be missing
>>>> something.
>>>>
>>> Not primary key, just a field having boolean choices.  Other examples of
>>> likely domains are
>>>     "POSTAL_CODE_DOMAIN"
>>>     "GENDER_DOMAIN"
>>>     "ADDRESS_DOMAIN"
>>
>>
>> I haven't seen the term domain used to describe the range of values an
>> attribute can hold in a long time.  I can see some advantages in such a
>> feature.   However, Oracle really does not offer a direct equilivent
>> nor do I think you want to use user types in your tables to provide
>> this functionality.
>>
>> I am of the opinion that objects, like java, belongs in the middle

>
> Mark,
>
> Thanks for your input.
>
> I wasn't really looking for object functionality, but rather a fixed
> field definition. So for example if I defined an address elsewhere, I
> don't have to remember that previously I defined an address as
> VARCHAR(36). Instead I just pick the ADDRESS_DOMAIN.
>
> Regards,
> Monte Carver

Once again Oracle has this capability and has had it since at least version 8.0.6.

Very simply:

SQL> CREATE OR REPLACE TYPE first_name AS OBJECT (

   2 first_name VARCHAR2(25));
   3 /

Type created.

SQL> CREATE OR REPLACE TYPE last_name AS OBJECT (

   2 last_name VARCHAR2(35));
   3 /

Type created.

SQL> CREATE TABLE person (

   2 fname first_name,
   3 lname last_name,
   4 dob DATE);

Table created.

SQL> desc person

  Name                                      Null?    Type
  ----------------------------------------- -------- ----------
  FNAME                                              FIRST_NAME
  LNAME                                              LAST_NAME
  DOB                                                DATE

SQL> I'd be highly inclined not to do it for many reasons but the capability is most certainly in Oracle.

-- 
Daniel A. Morgan
University of Washington
damorgan_at_x.washington.edu
(replace x with u to respond)
Puget Sound Oracle Users Group
www.psoug.org

Received on Fri Jan 19 2007 - 21:42:54 CST