有clients和lead_sources俩表。mysql数据库。

lead_sources表结构类似：

clients表中的lead_source_id是外键。现在要统计某时间段内client内每种lead_source所占百分比

select a.L_name, ROUND((a.L_sub_count*1.0/b.total_count*100),1) as perTotal,a.L_sub_count, b.total_countfrom(SELECT LeadSource.name as L_name, count(*) as L_sub_countFROM clients as Client,lead_sources as LeadSourcewhere     Client.lead_source_id = LeadSource.id     and LENGTH(Client.lead_source_id) > 0    and Client.created_date BETWEEN '2012-09-01' AND '2012-11-01'GROUP BY LeadSource.`name`order by L_sub_count desc)  a,(select count(*) as Total_count FROM clients as Client,lead_sources as LeadSource where         Client.lead_source_id = LeadSource.id     and LENGTH(Client.lead_source_id) > 0    and Client.created_date BETWEEN '2012-09-01' AND '2012-11-01') b;

这个SQL有三个select，所以看成三部分，我的理解，后两个是构造虚表和字段。目的就是用于第一个select的查询。

结果类似：