Question

我想使用case语句在一个表中更新一列但多行。这是更新声明：

UPDATE UDSDiagnosisGroups
SET UDSDiagnosisCategoryID = 
    CASE WHEN LineDisplay IN ('1-2', '3', '4', '4a', '4b') THEN (SELECT UDSDiagnosisCategoryID 
                                                                 FROM UDSDiagnosisCategories
                                                                 WHERE UDSDiagnosisCategory = 'Selected Infectious and Parasitic Diseases') 
         WHEN LineDisplay IN ('5', '6') THEN (SELECT UDSDiagnosisCategoryID 
                                              FROM UDSDiagnosisCategories
                                              WHERE UDSDiagnosisCategory = 'Selected Diseases of the Respiratory System')
         WHEN LineDisplay IN ('7', '8', '9', '10', '11', '12', '13', '14', '14a') THEN (SELECT UDSDiagnosisCategoryID 
                                                                                        FROM UDSDiagnosisCategories
                                                                                        WHERE UDSDiagnosisCategory = 'Selected Other Medical Conditions')
         WHEN LineDisplay IN ('15', '16', '17') THEN (SELECT UDSDiagnosisCategoryID 
                                                      FROM UDSDiagnosisCategories
                                                      WHERE UDSDiagnosisCategory = ' Selected Childhood Conditions (limited to ages 0 through 17)')
         WHEN LineDisplay IN ('18', '19', '19a', '20a', '20b', '20c', '20d') THEN (SELECT UDSDiagnosisCategoryID 
                                                                                   FROM UDSDiagnosisCategories
                                                                                   WHERE UDSDiagnosisCategory = 'Selected Mental Health and Substance Abuse Conditions')
    END                                           
FROM UDSDiagnosisGroups
WHERE UDSDiagnosisCategoryID IS NULL

问题是UDSDiagnosisGroups表中只更新了一行。更新的行是LineDisplay值1-2的行。所有其他值仍为NULL。

我哪里错了？它在我看来，我正在按照我找到的示例，但只更新了一行，而不是表中的所有行。

Answer 1

我建议将您的代码更改为类似的内容，它会更具可读性

array = array[0];

然后您可以播放case而不是case来查看UPDATE UDSDiagnosisGroups SET UDSDiagnosisCategoryID = d.UDSDiagnosisCategoryID from UDSDiagnosisGroups as g inner join UDSDiagnosisCategories as d on d.UDSDiagnosisCategory = case when g.LineDisplay in ('1-2', '3', '4', '4a', '4b') then 'Selected Infectious and Parasitic Diseases' when g.LineDisplay in ('5', '6') then 'Selected Diseases of the Respiratory System' when g.LineDisplay in ('7', '8', '9', '10', '11', '12', '13', '14', '14a') then 'Selected Other Medical Conditions' when g.LineDisplay in ('15', '16', '17') then ' Selected Childhood Conditions (limited to ages 0 through 17)' when g.LineDisplay in ('18', '19', '19a', '20a', '20b', '20c', '20d') then 'Selected Mental Health and Substance Abuse Conditions' where g.UDSDiagnosisCategoryID is null返回的行是否有效。你可能会有一些错别字。没有数据就很难说清楚。

Answer 2

可能是你的列值为空而不是空。使用 ISNULL 并重试

UPDATE UDSDiagnosisGroups
SET UDSDiagnosisCategoryID = 
    CASE WHEN LineDisplay IN ('1-2', '3', '4', '4a', '4b') THEN (SELECT UDSDiagnosisCategoryID 
                                                                 FROM UDSDiagnosisCategories
                                                                 WHERE UDSDiagnosisCategory = 'Selected Infectious and Parasitic Diseases') 
         WHEN LineDisplay IN ('5', '6') THEN (SELECT UDSDiagnosisCategoryID 
                                              FROM UDSDiagnosisCategories
                                              WHERE UDSDiagnosisCategory = 'Selected Diseases of the Respiratory System')
         WHEN LineDisplay IN ('7', '8', '9', '10', '11', '12', '13', '14', '14a') THEN (SELECT UDSDiagnosisCategoryID 
                                                                                        FROM UDSDiagnosisCategories
                                                                                        WHERE UDSDiagnosisCategory = 'Selected Other Medical Conditions')
         WHEN LineDisplay IN ('15', '16', '17') THEN (SELECT UDSDiagnosisCategoryID 
                                                      FROM UDSDiagnosisCategories
                                                      WHERE UDSDiagnosisCategory = ' Selected Childhood Conditions (limited to ages 0 through 17)')
         WHEN LineDisplay IN ('18', '19', '19a', '20a', '20b', '20c', '20d') THEN (SELECT UDSDiagnosisCategoryID 
                                                                                   FROM UDSDiagnosisCategories
                                                                                   WHERE UDSDiagnosisCategory = 'Selected Mental Health and Substance Abuse Conditions')
    END                                           
FROM UDSDiagnosisGroups
WHERE ISNULL(UDSDiagnosisCategoryID,'') = ''

使用case语句更新多行只更新1行

2 个答案: