One-to-one using a primary-key and foreign-key relationship : Primary Key « Table « Oracle PL/SQL Tutorial

SQL>
SQL>
SQL> CREATE TABLE Office
  2     (office_id        VARCHAR2(10) NOT NULL,
  3      building_name    VARCHAR2(20),
  4      PRIMARY KEY (office_id));

Table created.

SQL>
SQL> CREATE TABLE Programmer
  2     (lect_id    VARCHAR2(10) NOT NULL,
  3      lect_name  VARCHAR2(20),
  4      office_id  VARCHAR2(10),
  5      PRIMARY KEY (lect_id),
  6      FOREIGN KEY (office_id) REFERENCES Office (office_id)
  7      ON DELETE CASCADE);

Table created.

SQL>
SQL> drop table Office cascade constraints;

Table dropped.

SQL> drop table Programmer cascade constraints;

Table dropped.

6.15.Primary Key
	6.15.1.	Create a table with primary key, VARCHAR type column and date type column with default value
	6.15.2.	Alter table to insert primary key
	6.15.3.	Use combined column as the primary key
	6.15.4.	Try to add two primary keys to one table
	6.15.5.	All columns as primary key
	6.15.6.	One to many using a primary-key and foreign-key relationship
	6.15.7.	One-to-one using a primary-key and foreign-key relationship
	6.15.8.	Use three columns as primary key