Table in Oracle database set PRIMARY KEY auto-increment

There is no self-increment field in Oracle, which can be implemented indirectly via sequence + trigger, Sqlplus login in cmd and run directly. It usually takes a few steps:

1 Creating a data sheet

CreateTable test_increase (
            userid number (10)  primarykey,   /* primary key, automatically add */
           username  varchar2 20            );

2 Creating an auto-grow sequence

CREATESEQUENCE testincrease_sequence
INCREMENTBy1--Add a few each time
STARTWith 1      --  count starting from 1   
     nomaxvalue        --  does not set the maximum value   
      Nocycle          --  has been accumulating, does not cycle   
      cache 10

3 Creating a Trigger

CREATE TRIGGER test_increase before
Insert on Test_increase for each ROW
Begin
Select testincrease_sequence.nextval into: New.userid from dual;

end;

4 Submit

Commit

5 Testing

Execute the following statement repeatedly:

INSERT INTO test_increase (Username) values('Test')

6 View Insert Results:

UserID username

1 Test
2 Test
3 Test
4 test
5 test
6 test
7 Test
8 test
9 test

Turn:http://blog.163.com/[email protected]/blog/static/165190577201082910371842/

Table in Oracle database set PRIMARY KEY auto-increment