Single Row Object Type:

Single Row Object types are object types which are defined for specific columns and can contain singular value only such as other datatypes. They are created as objects that are additionally embedded as a datatype to a column.

Example

CREATE OR REPLACE TYPE user_date AS OBJECT# define a single row object#

(

day      number(2),

month number(2),

year     number(2)

);

CREATE OR REPLACE TYPE user_name AS OBJECT# define a single row object#  

(

fname varchar2(20),

mname varchar2(20),

lname varchar2(20)

);

CREATE TABLE employee_data

(

empno number(3),

ename  user_name,

dob      user_date,

salary   number(9,2)

);

The employee_data table is a relational table with an object type defining one of its columns. Objects which occupy columns of the relational table are known as COLUMN OBJECTS (EMBEDDED OBJECTS).