Question

我正在尝试使用以下代码根据join语句运行不同的CASE查询。

因此，如果customer CLI等于84422881，我希望它根据[Extenstion]字段加入，如果条件不满足，则ELSE则加入在[Customer CLI]

use VoiceflexBilling

CASE WHEN [dbo].[MARU15_OWH07579_Calls].[CustomerCLI] = '84422881' THEN

UPDATE [dbo].[MARU15_OWH07579_Calls] 
SET [dbo].[MARU15_OWH07579_Calls].[CustomerLookup] = CLIMapping.[customer id] 
FROM [BillingReferenceData].[dbo].[CLIMapping] 
INNER JOIN [VoiceflexBilling].[dbo].[MARU15_OWH07579_Calls] 
on [VoiceflexBilling].[dbo].[MARU15_OWH07579_Calls].[Extension] = [BillingReferenceData].[dbo].[CLIMapping].[CLI]

ELSE

UPDATE [dbo].[MARU15_OWH07579_Calls] 
SET [dbo].[MARU15_OWH07579_Calls].[CustomerLookup] = CLIMapping.[customer id] 
FROM [BillingReferenceData].[dbo].[CLIMapping] 
INNER JOIN [VoiceflexBilling].[dbo].[MARU15_OWH07579_Calls] 
on [VoiceflexBilling].[dbo].[MARU15_OWH07579_Calls].[CustomerCLI] = [BillingReferenceData].[dbo].[CLIMapping].[CLI]

END

目前我收到以下错误：

消息156，级别15，状态1，行3关键字附近的语法不正确＆＃39; CASE＆＃39 ;.消息156，级别15，状态1，行11附近的语法不正确关键字＆＃39; ELSE＆＃39;。消息102，级别15，状态1，行19语法不正确靠近＆＃39; END＆＃39;。

任何人都可以帮助使用正确的语法吗？

谢谢，

Answer 1

对您的查询提出一些意见。首先，case是表达式，而不是控制流。所以，它属于查询。其次，您可以使用“常规”逻辑进行此查询。第三，表别名会使查询更容易编写和阅读：

UPDATE c 
SET c.[CustomerLookup] = CLIMapping.[customer id] 
FROM [VoiceflexBilling].[dbo].[MARU15_OWH07579_Calls] cm
     [BillingReferenceData].[dbo].[CLIMapping] c INNER JOIN
     on (c.[CustomerCLI] = '84422881' AND c.[Extension] = cm.[CLI]) or
        (c.[CustomerCLI] <> '84422881' AND c.[CustomerCLI] = cm.[CLI])

Answer 2

您可以使用case中的join condition声明：

UPDATE [dbo].[MARU15_OWH07579_Calls] 
SET [dbo].[MARU15_OWH07579_Calls].[CustomerLookup] = CLIMapping.[customer id] 
FROM [BillingReferenceData].[dbo].[CLIMapping] 
INNER JOIN [VoiceflexBilling].[dbo].[MARU15_OWH07579_Calls] 
ON [BillingReferenceData].[dbo].[CLIMapping].[CLI] = 
 CASE WHEN [dbo].[MARU15_OWH07579_Calls].[CustomerCLI] = '84422881' 
                 THEN [VoiceflexBilling].[dbo].[MARU15_OWH07579_Calls].[Extension]
      ELSE [VoiceflexBilling].[dbo].[MARU15_OWH07579_Calls].[CustomerCLI] 
 END

Answer 3

案例必须出现在查询中。对于您的场景，我建议您编写代码如下:(我需要实现循环迭代所有记录，在这种情况下，您需要稍微修改一下这段代码）

DECLARE @p varchar(100)
SET @p=(SELECT TOP 1 [dbo].[MARU15_OWH07579_Calls].[CustomerCLI] FROM [dbo].[MARU15_OWH07579_Calls])
IF @p = '84422881'
   UPDATE [dbo].[MARU15_OWH07579_Calls] 
   SET [dbo].[MARU15_OWH07579_Calls].[CustomerLookup] = CLIMapping.[customer id] 
   FROM [BillingReferenceData].[dbo].[CLIMapping] 
   INNER JOIN [VoiceflexBilling].[dbo].[MARU15_OWH07579_Calls] 
   on [VoiceflexBilling].[dbo].[MARU15_OWH07579_Calls].[Extension] =[BillingReferenceData].[dbo].[CLIMapping].[CLI]

ELSE
   UPDATE [dbo].[MARU15_OWH07579_Calls] 
   SET [dbo].[MARU15_OWH07579_Calls].[CustomerLookup] = CLIMapping.[customer id] 
   FROM [BillingReferenceData].[dbo].[CLIMapping] 
   INNER JOIN [VoiceflexBilling].[dbo].[MARU15_OWH07579_Calls] 
   on [VoiceflexBilling].[dbo].[MARU15_OWH07579_Calls].[CustomerCLI] = [BillingReferenceData].[dbo].[CLIMapping].[CLI]

基于案例查询的不同连接/更新

3 个答案: