sql server 一对多统计数量

Answer 1

数据

我这里叫a,b,c了，跟你表1，2，3是对应的

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create table a(uid int,name varchar(10))

insert into a values (1,'张一')

insert into a values (2,'张二')

 

 

create table b (uid int,type1 varchar(1))

insert into b values (1,'a')

insert into b values (1,'b')

insert into b values (1,'c')

insert into b values (2,'b')

insert into b values (2,'c')

 

 

 

create table c(uid int,type2 varchar(1))

insert into c values (1,'a')

insert into c values (2,'b')

insert into c values (2,'c')

运行

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select t1.uid,t2.c1,t3.c2 from a t1

left join 

(select uid,count(*) c1 from b group by uid) t2 on t1.uid=t2.uid

left join 

(select uid,count(*) c2 from c group by uid) t3 on t1.uid=t3.uid

 

结果