Use int as column type : int « SQL Data Types « Oracle PL/SQL Tutorial

1. Oracle PL/SQL Tutorial
2. SQL Data Types
3. int

SQL>
SQL>
SQL> create table t3
  2  (  x int primary key,
  3     y varchar2(25),
  4     z date
  5  )
  6  organization index
  7  overflow INCLUDING y;

Table created.

SQL>
SQL>
SQL> drop table t3;

Table dropped.

SQL>