如何在MYSQL中从客户处获取特定名称？

我创建以下表格：

create table customers
(
        ID             varchar(9),
        name           varchar(15),  

CONSTRAINT pk_id PRIMARY KEY (ID)
);


create table living_places
(
        code     varchar(7),
        ID      varchar(9),

CONSTRAINT pk_code PRIMARY KEY (code)
);

create table policies
(
        code_policy         varchar(7),
        code_living_place       varchar(7),

CONSTRAINT pk_code_policy PRIMARY KEY (code_policy)
);

create table accidents
(
        code_accident         varchar(7),
        code_policy       varchar(7),

CONSTRAINT pk_code_accident PRIMARY KEY (code_accident)
);

我插入了以下日期：

insert into customers(ID, name) 
values('fx1','Louis');
insert into customers(ID, name) 
values('fx2','Peter');
insert into customers(ID, name) 
values('fx3','Alice');

insert into living_places(code, ID) 
values('001','fx1');
insert into living_places(code, ID) 
values('002','fx2');
insert into living_places(code, ID) 
values('003','fx1');
insert into living_places(code, ID) 
values('004','fx3');

insert into policies(code_policy, code_living_place) 
values('p1','001');
insert into policies(code_policy, code_living_place) 
values('p2','002');
insert into policies(code_policy, code_living_place) 
values('p3','003');

insert into accidents(code_accident, code_policy) 
values('A1','p1');
insert into accidents(code_accident, code_policy) 
values('A2','p2');

问题是：如何选择保险单中没有发生事故的客户

我的问题是，当我试图使用“notin”时。如果“Louis”表中至少有一个策略为“意外”，则查询将显示“Louis”，而不应显示“Louis”

我的问题是：

create or replace view view as
select code from living_places v where code not in (
  select distinct a.code_living_place  from 
    policies as a inner join accidents as c 
    on a.code_policy = c.code_policy 
);

select name from customers where ID in (select ID from living_places where code in (select code from view where code in (select code_living_place from policies)));

MySQL返回我：

+-------+
| name  |
+-------+
| Louis |
+-------+

---

不在和内部联接中使用

select name from customers 
where customers.id not in (select living_places.id 
        from living_places
        inner join policies on policies.code_living_place = living_places.code
        inner join accidents on accidents.code_policy =  policies.code_policy);

---

如果子查询返回空值，

不在

中，可能会让许多用户感到惊讶。我的建议是要么使用

不存在

，要么确保子查询不返回任何空值。为什么要使用那些奇怪的id列数据类型？整数怎么了？

select name from customers 
where customers.id not in (select living_places.id 
        from living_places
        inner join policies on policies.code_living_place = living_places.code
        inner join accidents on accidents.code_policy =  policies.code_policy);