Oracle creates a table that automatically adds a primary key

Oracle creates a table that automatically adds a primary key // creates a table
Create Table T (Pk Number Primary Key, name varchar2 (20 ));

// Create a sequence
Create sequence t_seq
Increment by 1
Start with 1 maxvalue 999999999;

// Create a trigger
Create trigger t_trigger before insert on T for each row
Begin
Select t_seq.nextval into: New. PK from dual; // or (New. PK = t_seq.nextval)
End;

// Insert record
Insert into T (name) values ('A ');

Http://www.cnblogs.com/skl99/archive/2009/01/06/1370450.html