sql - 使用 case 语句更新字段

Question

对于以下查询结果中的以下人物，UniqueIDSuffix 值应使用前导 0 填充，字符长度 = 6。UniqueIDSuffix 修改后，UniqueID 值应通过 UniqueIDPrefix + UniqueIDSuffix = UniqueID 更新为字符长度 = 9

select * from cph..cppat (nolock) where 
UniqueIDPrefix is not null and 
UniqueIDPrefix <> 'VIS' and len(UniqueIDSuffix) < 6

按 UniqueIDPrefix asc 排序

我的声明是：

SET UniqueIDsuffix  =
        (CASE
           WHEN UniqueIDsuffix = 3 THEN '000' + UniqueIDsuffix  ELSE
           When UniqueIDsuffix = 4 THEN '00' + UniqueIDsuffix ELSE
           WHEN UniqueIDsuffix = 5 Then '0' + UniqueIDsuffix ELSE
           WHEN UniqueIDsuffix = 6 THEN UniqueIDsuffix ELSE
           )
where UniqueIDPrefix is not null and UniqueIDPrefix <> 'VIS' 
and len(UniqueIDSuffix) < 6

Answer 1

您缺少更新语句。. . 你有无关的else陈述。. . 并且您缺少len()比较中的功能：

update cph..cppat
    SET UniqueIDsuffix  =
            (CASE WHEN len(UniqueIDsuffix) = 3 THEN '000' + UniqueIDsuffix 
                  When len(UniqueIDsuffix) = 4 THEN '00' + UniqueIDsuffix 
                  WHEN len(UniqueIDsuffix) = 5 Then '0' + UniqueIDsuffix 
                  WHEN len(UniqueIDsuffix) = 6 THEN UniqueIDsuffix 
            )
    where UniqueIDPrefix is not null and UniqueIDPrefix <> 'VIS' and len(UniqueIDSuffix) < 6

顺便说一句，您可以更简单地表示为：

update cph..cppat
    SET UniqueIDsuffix  = right('0000000'+UniqueIDSuffix, 6)
    where UniqueIDPrefix is not null and UniqueIDPrefix <> 'VIS' and len(UniqueIDSuffix) < 6