1
比方說,我有一個名爲MyAssembly
的程序集,其類別MyClass
有一個MyFunction(long timestamp)
方法(它將datetime作爲字符串以YYYY-MM-DD HH24:mm:ss
的格式返回)。如果我創建一個腳本這樣的工作:即使參數相同(連續),函數是否會被多次調用?
@outputData =
SELECT MyAssembly.MyClass.MyFunction(t1.timestamp).Substring(0,4) AS Year
,MyAssembly.MyClass.MyFunction(t1.timestamp).Substring(...) AS Month
,MyAssembly.MyClass.MyFunction(t1.timestamp).Substring(...) AS Day
,MyAssembly.MyClass.MyFunction(t1.timestamp).Substring(...) AS Hour
,MyAssembly.MyClass.MyFunction(t1.timestamp).Substring(...) AS Minute
,MyAssembly.MyClass.MyFunction(t1.timestamp).Substring(...) AS Second
FROM @queryInput AS t1
會在功能被多次調用或將系統是「聰明」,足以把它只有一次,使用返回值的其他列?如果不是,我有什麼選擇?