2个表联合查询的问题，需要统计B表的列数，大大们帮忙啊
现有2个表：
A表：
id c_name
1 a客户
2 b客户
3 c客户
====================
B表(customer_id就是a表的id)：
id customer_id project_type
1 1 JH
2 1 HT
3 1 FW
4 1 HT
5 2 JH
......
====================================
现需要做联合查询，得出类似与下面的数据列
客户名称 JH HT FW 合计
a客户 1个 2个 1个 4个
b客户 1个 0个 0个 1个
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也就是说不单单是要统计客户的 project_type 数量，而且还要得出每个类型（已固定只有三种类型）的具体数量 ，这个sql应该怎么写？？请大大门赐教啊~~~~~~~~~~~~~~~~~~~~~~~~
[解决办法]
select a.c_name,
sum(if(project_type='JH',1,0)) AS JH,
sum(if(project_type='HT',1,0)) AS HT,
sum(if(project_type='FW',1,0)) AS FW,
COUNT(*) AS 合计
from a inner join b on a.id=b.customer_id
group by a.c_name
[解决办法]
select a.c_name, sum(if(project_type='JH',1,0)) as JH, sum(if(project_type='HT',1,0)) as HT, sum(if(project_type='FW',1,0)) as FW, count(*) as 合计from a , bwhere a.id=b.customer_idgroup by a.c_name
