如何根据颜色ID确定图像类型

Question

我有一个表并希望使用COLORID为具有相同ID的记录填充ImageType_page。

条件：

• 如果任何页＃具有相同ID的具有COLORID = 1，SET ImageType_page =对所有页＃同一ID
• 如果内TIFF任何页＃与同样的ID有COLORID = 2，SET ImageType_page = TIFF，JPEG对于同一ID

这里内的所有页＃是我的表：

Page#  | ID | PageColor  | COLORID | ImageType_page 
AT000001 | 1 | Black & White |  1  | 
AT000002 | 1 | Color   |  2  | 
AT000003 | 2 | Color   |  2  | 
AT000004 | 2 | Black & White |  1  | 
AT000005 | 3 | Black & White |  1  | 
AT000006 | 3 | Black & White |  1  | 

个

结果应该是：

Page# | ID | PageColor  | COLORID | ImageType_page 

AT000001 | 1 | Black & White |  1  | TIFF-JPEG 
AT000002 | 1 | Color   |  2  | TIFF-JPEG 
AT000003 | 2 | Color   |  2  | TIFF-JPEG 
AT000004 | 2 | Black & White |  1  | TIFF-JPEG 
AT000005 | 3 | Black & White |  1  | TIFF 
AT000006 | 3 | Black & White |  1  | TIFF 

下面是一些代码，我写了不起作用。任何帮助将不胜感激。

update dbo.tblPage 
set [IMAGE TYPE_page] = 'TIFF-JPEG' 
Where [COLORID] = 2 

update td 
set [IMAGE TYPE_page] = (select [IMAGE TYPE_page] FROM tblPAGE td2 where td2.id = td.ID) 
from tblPAGE td 
where (COLORID = 1) 

Answer 1

一种方法是让所有有ColorID = 2的ID，并加入到在更新：

with cte as 
(
    select distinct id from tblPage where colorid = 2 
) 
update tbl 
set imagetype = CASE WHEN cte.id IS NOT NULL THEN 'TIFF-JPEG' ELSE 'TIFF' END 
from tblPage tbl 
left join cte on cte.id = tbl.id 

另外，您可以按ID，并查找最大ColorID：

with cte as 
(
    select id, max(colorid) as maxcolorid 
    from tblPage 
    group by id 
) 
update tbl 
set imagetype = CASE cte.maxcolorid WHEN 2 THEN 'TIFF-JPEG' ELSE 'TIFF' END 
from tblPage tbl 
inner join cte on cte.id = tbl.id