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How can I make a single element of a user type required?
The following is found in Oracle's Documentation to illustrate my question.
CREATE TYPE Person AS OBJECT (
first_name VARCHAR2(15),
last_name VARCHAR2(15),
birthday DATE,
home_address REF Address, -- shared with other Person objects
phone_number VARCHAR2(15))
/
CREATE TABLE department (
dept_name VARCHAR2(20),
manager Person,
location VARCHAR2(20))
/
What would I do if I wanted to manager.make first_name and
manager.last_name required in the
department table?
I found that I can add any constraint other than not null to a specific component.
CREATE TABLE department (
dept_name VARCHAR2(20),
manager Person,
location VARCHAR2(20),
Constraint ATest UNIQUE (manager.first_name, manager.last_name))
/
I realize that 'create table of' will allow 'not null' constraints to
be implemented without hassle
but then I would lose the benefit of inheritance if I had to create a
new data type for
every table.
Thanks in advance for your expert help!
Todd Logan
DBA
toddl_at_farmclub.com
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Received on Thu Jun 29 2000 - 00:00:00 CDT