case when then else end 能用在条件判断上么比如select * from app a where --在这加case when 可以么?select * from app a where case when a.id = 1 then a.name = '22' else a.name = '33'
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![case when then else end 能用在条件判断上么比如select * from app a where --在这加case when 可以么?select * from app a where case when a.id = 1 then a.name = '22' else a.name = '33'](/uploads/image/z/3684647-47-7.jpg?t=case+when+then+else+end+%E8%83%BD%E7%94%A8%E5%9C%A8%E6%9D%A1%E4%BB%B6%E5%88%A4%E6%96%AD%E4%B8%8A%E4%B9%88%E6%AF%94%E5%A6%82select+%2A+from+app+a+where+--%E5%9C%A8%E8%BF%99%E5%8A%A0case+when+%E5%8F%AF%E4%BB%A5%E4%B9%88%3Fselect+%2A+from+app+a+where+case+when+a.id+%3D+1+then+a.name+%3D+%2722%27+else+a.name+%3D+%2733%27)
case when then else end 能用在条件判断上么比如select * from app a where --在这加case when 可以么?select * from app a where case when a.id = 1 then a.name = '22' else a.name = '33'
case when then else end 能用在条件判断上么
比如
select * from app a where --在这加case when 可以么?
select * from app a where case when a.id = 1 then a.name = '22' else a.name = '33'
case when then else end 能用在条件判断上么比如select * from app a where --在这加case when 可以么?select * from app a where case when a.id = 1 then a.name = '22' else a.name = '33'
可以!
where expression
但是expression 必须是返回布尔值的表达式
--------------------------------------
比如
SELECT [OrderID]
,[CustomerID]
,[EmployeeID]
,[OrderDate]
,[RequiredDate]
,[ShippedDate]
,[ShipVia]
,[Freight]
,[ShipName]
,[ShipAddress]
,[ShipCity]
,[ShipRegion]
,[ShipPostalCode]
,[ShipCountry]
FROM [Northwind].[dbo].[Orders] where case when [CustomerID]='VINET' then [EmployeeID] end >1