Oracle触发器实现主键自增效果

CREATE TABLE testUser ( id NUMBER ( 11 ) primary key, name VARCHAR ( 50 ) );

CREATE sequence seq_testUser minvalue 1 maxvalue 99999999 START WITH 1 INCREMENT BY 1 nocache ORDER;

CREATE 
	OR REPLACE TRIGGER trg_seq_testUser BEFORE INSERT ON testUser FOR EACH ROW
BEGIN
	SELECT
		seq_testUser.nextval INTO : new.id 
	FROM
		dual;
	
END;

insert into testUser(username) values('强哥0');
insert into testUser(username) values('强哥1');
insert into testUser(username) values('强哥2');

select * from testUser