Question

我在SQL Server 2012中有2个数据库我正在尝试创建一个触发器来将表从一个数据库更新到第二个数据库中的表，该表将包含任务的历史记录我正在“尝试”在更新语句中使用CASE表达式，但我不断收到错误的语法错误：'='附近的语法不正确这是触发器：

USE [Employees]
GO

SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TRIGGER [dbo].[trigger_task_list]
ON [dbo].[Employee_Timesheets]
FOR INSERT, UPDATE
AS
BEGIN
SET EMPID = CASE WHEN EMPID = 2  THEN 'Carol'     
             WHEN EMPID = 3  THEN 'Joan'          
             WHEN EMPID = 4  THEN 'Jess'         
             WHEN EMPID = 5  THEN 'Linda'        
             WHEN EMPID = 6  THEN 'Tanya'     
             WHEN EMPID = 7  THEN 'Sarah'        ELSE EMPID END

SET TaskNo = CASE WHEN TaskNo = 10 THEN 'Prepare Invoices' 
              WHEN TaskNo = 20 THEN 'Log Invoices'             
              WHEN TaskNo = 30 THEN 'Print Invoices'       
              WHEN TaskNo = 40 THEN 'Run Reports' ELSE TaskNo END

SET NOCOUNT ON

INSERT INTO employeedashboard.dbo.task_list_history (emp_id,dep_id,task_id,date_time)

SELECT EMPID AS emp_id, department as dep_id, (SELECT TaskNo FROM Employee_Timesheets WHERE TaskNo = 20) AS task_id, GETDATE() AS date_time

FROM inserted 

END

任何建议解决此问题/优化查询我真的很感激

Answer 1

我认为你要做的是这样的事情：

INSERT INTO employeedashboard.dbo.task_list_history (emp_id,dep_id,task_id,date_time)

SELECT 
    CASE WHEN EMPID = 2  THEN 'Carol'     
       WHEN EMPID = 3  THEN 'Joan'          
       WHEN EMPID = 4  THEN 'Jess'         
       WHEN EMPID = 5  THEN 'Linda'        
       WHEN EMPID = 6  THEN 'Tanya'     
       WHEN EMPID = 7  THEN 'Sarah'        
       ELSE EMPID 
    END AS emp_id
    , department as dep_id
    , TaskNo = 
       CASE WHEN TaskNo = 10 THEN 'Prepare Invoices' 
          WHEN TaskNo = 20 THEN 'Log Invoices'             
          WHEN TaskNo = 30 THEN 'Print Invoices'       
          WHEN TaskNo = 40 THEN 'Run Reports' 
          ELSE TaskNo 
    END AS task_id
    , GETDATE() AS date_time
FROM inserted

请注意，这是未经测试的，纯粹基于我对您认为您尝试做的事情的解释......

但是，我同意戈登的观点。不是在这里编写case语句，而是将这些值存储在您加入的查找表中。这将确保您可以在将来轻松添加或删除值，而无需更改代码。

TRIGGER中的SQL CASE

1 个答案: