Oracle没有设置主键auto increment 的功能,需要自己白那些序列和触发器实现主键自动递增。
Oracle没有设置主键auto increment 的功能,需要自己白那些序列和触发器实现主键自动递增。
示例:
创建表menu:
create table menu( menuId number(10) not null primary key,
name varchar2(40) not null,
id_parent number(10) not null,
url varchar2(300) null);
创建序列menu_autoinc_seq:
create sequence menu_autoinc_seq
minvalue 1
maxvalue 99999999
start with 1
increment by 1
nocycle
nocache
order;
创建触发器menu_autoinc_tg:
create or replace trigger menu_autoinc_tg
before insert on menu for each row
begin
select menu_autoinc_seq.nextval into :new.menuId from dual;
end menu_autoinc_tg;
其中end语句可以写成end;
在Command window进行创建数据库对象的时候,如果使用到了多行语句,,可在结束后另起一行输入/
测试:
insert into menu values('','个人事务',0,'indi.php');
insert into menu values('','公共事务',0,'public.php');

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