sql多表行转列、级联行转列示例代码

现有两表a，b

a表存储商品点击日志，b表存储商品

要求显示当天所有商品点击量列表并附带总数并按天排序

declare @sql varchar(2000)
set @sql='select convert(varchar(100), a.[time], 23) as 时间,count(b.title) as 总数'
select @sql =@sql+ ',sum(case b.title when '''+title+''' then 1 else 0 end) as '+'['+title+']'
from (select distinct title from b) as b
set @sql=@sql+' from a as a left join b as b on a.aid=b.aid
group by convert(varchar(100), a.[time], 23) order by convert(varchar(100), a.[time], 23) desc'
exec(@sql)

显示结果

时间	总数	商品1	商品2	商品3
2013-11-11	5	1	0	4
2013-11-10	13	2	11	1