Create a primary key auto-increment table in Oracle

1. Create a table

 
Create TableTest_increase (useridNumber(10)Not Null Primary Key,/*Primary Key, automatically added*/UsernameVarchar2(20));
 

2,Create auto-increment Sequence

 CreateSequence testincrease_sequence IncrementBy 1--Add a fewStartWith 1--Count from 1Nomaxvalue--If the maximum value is not set, set the maximum value to maxvalue 9999.Nocycle--Always accumulate, not loopCache10;
 

3,Create a trigger

Create TriggerTest_increase beforeInsert OnTest_increaseForEach row/*Checks whether each row is triggered.*/BeginSelectTestincrease_sequence.nextvalInto: New. useridFromDual;End;//*Exit sqlplus row Edit*/
 

4. Submit

Commit ; 5. Test

 
Insert IntoTest_increase (username)Values('Test');
 

From: http://www.cnblogs.com/lizhishugen/archive/2012/11/29/2794692.html