有表T1,结构如下:
A B
a1 0
a1 NULL
a2 NULL
a2 NULLselect A,count(B) from T1
where B=0
group by A
本想得到如下结果:
a1 1
a2 0
但不如意,只得到a1 1的结果,不知道怎么样才能得到想要的结果?
A B
a1 0
a1 NULL
a2 NULL
a2 NULLselect A,count(B) from T1
where B=0
group by A
本想得到如下结果:
a1 1
a2 0
但不如意,只得到a1 1的结果,不知道怎么样才能得到想要的结果?
解决方案 »
- SetScrollInfo在MDI窗体不生效?
- 请教会点vb的,怎样能把这个vb的代码翻译成delphi的,谢谢了
- Delphi的MD5函数加密后有没有是这种结果的?
- strtohex函数问题。大侠们请进
- 我将TLabel改了一下,生成了dpk,安装的时候也没什么不对,但在标签栏上就是看不到,请问如何解决?
- Kaersoft软件基地,很多DELPHI参考程序,需要东西的快去下载!
- 关于 bulid compile 的问题
- 帮忙呀~~~~~~~~~~~~~~~~~~~~~~我狂给分呀~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- 关于票据打印。急!!!!
- 新手,仍旧是新手.
- 折磨多日!苦等!如何检查远程IP主机的某个服务端口是否开放?
- excel中新增一个工作表
Where IsNull(B, 0)=0
Group by A
select A,count(B) from T1 group by A
a1 1
a2 0
呢?
Where IsNull(B, 0)=0
Group by A//如果B是null就把它转换为0
From T1
Left Join (
Select A, Count(B) As B2
From T1
Where B=0
Group by A ) As T2
On T1.A=T2.A
Order By T1.A
From (Select A From T1 Group by A) As T2
Left Join (Select A, Count(A) As A1
From T1 Where B=0 Group By A) As T3
On T2.A=T3.A
Order by T2.A