夫妻表增删改查实例

-- 1..1  crud 插入  
drop table hunsband;
drop table wife;

create table hunsband(
       id number constraint hunsband_id_pk primary key,
       name varchar2(255) constraint hunsband_name_nn not null,
      salary number,
      birthday date
);

create table wife(
       id number constraint wife_id_pk primary key,
       name varchar2(255) constraint wife_name_nn not null,
       salary number,
       birthday date,
       hunsband_id number  references hunsband(id)
);
-- 1..1  插入数据时，尤其是插入外键时，那么一定关联的表中主键列出现过的值
insert into hunsband values(1,'pantf',2000,'1-1月-2020');
insert into hunsband values(2,'mapp',2000,'1-1月-2019');

insert into wife values(1,'taost',3000,'1-1月-2019',1);

insert into wife values(2,'zhangtt',5000,'1-1月-2020',2);

--insert into wife values(3,'matt',5000,'1-1月-2020',3);
-- 更新 
-- 更新没有外键的表
update hunsband set name = 'ddd' where id = 1;
--更新没有外键表的主键
update hunsband set  id = 10 where name = 'mapp';

insert into hunsband(id,name) values(12,'wangzh');
update hunsband set id = 15 where name = 'wangzh';
-- 修改数据时该数据没有被关联 那么就可以修改主键列，如果被关联那么就可以修改非主键列

-- 更新 妻子表   修改外键表并不对对被关联并没有产生任何的影响，可以随意修改
select * from wife;
update wife set id = 18 where name = 'zhangtt';
-- 修改外键一定是要修改成关联的表中主键列存在的值
update wife set hunsband_id = 151 where id = 18;
-- 删除
-- 删除丈夫数据
delete from hunsband where id = 1 ;

-- 删除妻子数据 删除有外键表的数据对关联的表没有影响
delete from wife;
select * from wife;
select * from hunsband;

delete from hunsband;
-- 如果说我非要 直接删除丈夫
-- 从建表的时候就需要指定当关联的主键被删除时候，外键应该进行什么样的操作
-- on delete no action
-- on delete cascade  当被关联表中数据删除时，那么外键数据也级联删除
-- on delete set null 当被关联的表中的数据删除时 外键质控
drop table wife;
drop table hunsband;

create table hunsband(
       id number constraint hunsband_id_pk primary key,
       name varchar2(255) constraint hunsband_name_nn not null,
      salary number,
      birthday date
);

create table wife(
       id number constraint wife_id_pk primary key,
       name varchar2(255) constraint wife_name_nn not null,
       salary number,
       birthday date,
       hunsband_id number references hunsband(id) on delete cascade
);

select * from hunsband;
select * from wife;

insert into hunsband values(1,'pantf',2000,'1-1月-2019');
insert into hunsband values(2,'wangzh',3000,'1-2月-2019');

insert into wife values(1,'taost',2000,'1-1月-2019',1);

delete from hunsband where id = 1;


drop table wife;
drop table hunsband;