Enforcement of Primary Key Constraints

An anonymous PRIMARY KEY constraint on the column ID:

SQL> CREATE TABLE myTable
  2  (ID   NUMBER PRIMARY KEY,
  3   NAME VARCHAR2(20)
  4  );

Table created.

SQL>

Give constraint a name:

SQL> CREATE TABLE myTable
  2  (ID   NUMBER CONSTRAINT ID_PK PRIMARY KEY,
  3   PORT_NAME VARCHAR2(20)
  4  );

Table created.

SQL>