ตอนที่ 16 : การสร้าง Function บน Server Database (SQL Server : Function)

CREATE FUNCTION <Inline_Function_Name, sysname, FunctionName> 
(	
	-- Add the parameters for the function here
	<@param1, sysname, @p1> <Data_Type_For_Param1, , int>, 
	<@param2, sysname, @p2> <Data_Type_For_Param2, , char>
)
RETURNS Data_Type
AS
BEGIN
	-- Add the Return data
	RETURN Variable
END

CREATE FUNCTION GetDiffAmount 
(	
	@pAmount1 DECIMAL(18,2),
	@pAmount2 DECIMAL(18,2)
)
	RETURNS DECIMAL(18,2) 
AS BEGIN
	DECLARE @diffAmt DECIMAL(18,2)

	SET @diffAmt = @pAmount1 - @pAmount2
		
	RETURN @diffAmt
END

SELECT dbo.GetDiffAmount(2000, 500) As DiffAmt

SELECT *, dbo.getDiffAmount(BUDGET,USED) AS DiffAmount FROM CUSTOMER