mysql取差集、交集、并集

mysql取差集、交集、并集
 
博客分类： Mysql数据库
 
需求：从两个不同的结果集（一个是子集，一个是父集），字段为电话号码phone_number,找出父集中缺少的电话号码，以明确用户身份。
结合网上资料，整理sql如下： 
 
//mysql取差集 
 
Java代码  收藏代码
select num FROM
(  
 
select u.code_sn as id,u.phone_number as num from t1 b
left join t2 u
on b.from_user=u.code_sn
where b.to_account='' and b.json_info like '%09月份%'  
 
union all  
 
select u.code_sn as id,u.phone_number as num from t3 o
left join t2 u
on o.buyer_code_sn=u.code_sn
where o.seller_account_code_sn='' and o.json_info like '%09月份%'   
 
)t3
group by num having count(num)=1  
 
//mysql取交集 
 
Java代码  收藏代码
select num FROM
(  
 
select u.code_sn as id,u.phone_number as num from t1 b
left join t2 u
on b.from_user=u.code_sn
where b.to_account='' and b.json_info like '%09月份%'  
 
union all  
 
select u.code_sn as id,u.phone_number as num from t1 o
left join t2 u
on o.buyer_code_sn=u.code_sn
where o.seller_account_code_sn='' and o.json_info like '%09月份%'   
 
)t3
group by num having count(num)=2  
 
//mysql取并集 
 
Java代码  收藏代码
select num FROM
(  
 
select u.code_sn as id,u.phone_number as num from t1 b
left join t2 u
on b.from_user=u.code_sn
where b.to_account='' and b.json_info like '%09月份%'  
 
union all  
 
select u.code_sn as id,u.phone_number as num from t1 o
left join t2 u
on o.buyer_code_sn=u.code_sn
where o.seller_account_code_sn='' and o.json_info like '%09月份%'   
 
)t3