SQL KTF Gelir Vergisini Hesaplayan KTF

CREATE FUNCTION FN_GELIRVERGISI (@KMATRAH AS FLOAT,@VMATRAH AS FLOAT)

RETURNS FLOAT AS
BEGIN
DECLARE @SONUC AS FLOAT
DECLARE @DILIM1 AS FLOAT
DECLARE @DILIM2 AS FLOAT
DECLARE @DILIM3 AS FLOAT
DECLARE @DILIM4 AS FLOAT
DECLARE @ORAN1 AS INT
DECLARE @ORAN2 AS INT
DECLARE @ORAN3 AS INT
DECLARE @ORAN4 AS INT
DECLARE @GV1 AS FLOAT
DECLARE @GV2 AS FLOAT
DECLARE @GV3 AS FLOAT
DECLARE @GV4 AS FLOAT
DECLARE @TMATRAH AS FLOAT
DECLARE @SOR AS FLOAT

SET @DILIM1 = 0
SET @DILIM2 = 14800
SET @DILIM3 = 34000
SET @DILIM4 = 120000
SET @ORAN1 =15
SET @ORAN2 =20
SET @ORAN3 =27
SET @ORAN4 =35

SET @TMATRAH = @KMATRAH + @VMATRAH
IF @TMATRAH<=@DILIM2
BEGIN
SET @GV1=@VMATRAH*@ORAN1/100
SET @SONUC=@GV1
RETURN @SONUC
END

IF @TMATRAH>=@DILIM2 AND @TMATRAH<@DILIM3
BEGIN
SET @SOR = (@VMATRAH - (@TMATRAH - @DILIM2))
IF @SOR>0
BEGIN
SET @GV1=(@TMATRAH-@DILIM2)*@ORAN2/100
SET @GV2=@SOR*@ORAN1/100
END
ELSE
BEGIN
SET @GV1=@VMATRAH*@ORAN2/100
SET @GV2 = 0
END
SET @SONUC=@GV1+@GV2
RETURN @SONUC
END

IF @TMATRAH>=@DILIM3 AND @TMATRAH<@DILIM4 AND @KMATRAH<@DILIM2
BEGIN
SET @GV1=(@DILIM2-@KMATRAH)*@ORAN1/100
SET @GV2=(@DILIM3-@DILIM2)*@ORAN2/100
SET @GV3=(@TMATRAH-@DILIM3)*@ORAN3/100
SET @SONUC= @GV1 + @GV2 + @GV3
RETURN @SONUC
END

IF @TMATRAH>=@DILIM3 AND @TMATRAH<@DILIM4 AND @KMATRAH>@DILIM2
BEGIN
SET @SOR=(@VMATRAH-(@TMATRAH-@DILIM3))
IF @SOR>0
BEGIN
SET @GV1 = (@TMATRAH - @DILIM3) * @ORAN3 / 100
SET @GV2 = @SOR * @ORAN2 / 100
END
ELSE
BEGIN
SET @GV1 = @VMATRAH * @ORAN3 / 100
SET @GV2 = 0
END
SET @SONUC= @GV1 + @GV2
RETURN @SONUC
END

IF @TMATRAH>=@DILIM4 AND @KMATRAH<@DILIM2
BEGIN
SET @GV1=(@DILIM2-@KMATRAH)*@ORAN1/100
SET @GV2=(@DILIM3-@DILIM2)*@ORAN2/100
SET @GV3=(@DILIM4-@DILIM3)*@ORAN3/100
SET @GV4=(@TMATRAH-@DILIM4)*@ORAN4/100
SET @SONUC= @GV1 + @GV2 + @GV3+ @GV4
RETURN @SONUC
END

IF @TMATRAH>=@DILIM4 AND @KMATRAH<@DILIM3
BEGIN
SET @GV1=0
SET @GV2=(@DILIM3-@KMATRAH)*@ORAN2/100
SET @GV3=(@DILIM4-@DILIM3)*@ORAN3/100
SET @GV4=(@TMATRAH-@DILIM4)*@ORAN4/100
SET @SONUC= @GV1 + @GV2 + @GV3+ @GV4
RETURN @SONUC
END

IF @TMATRAH>=@DILIM4 AND @KMATRAH<@DILIM4
BEGIN
SET @SOR=(@VMATRAH-(@TMATRAH-@DILIM4))
IF @SOR>0
BEGIN
SET @GV1 = (@TMATRAH - @DILIM4) * @ORAN4 / 100
SET @GV2 = @SOR * @ORAN3 / 100
END
ELSE
BEGIN
SET @GV1 = @VMATRAH * @ORAN4 / 100
SET @GV2 = 0
END
SET @SONUC= @GV1 + @GV2
RETURN @SONUC
END

IF @KMATRAH>=@DILIM4
BEGIN
SET @GV1=@VMATRAH*@ORAN4/100
SET @SONUC=@GV1
RETURN @SONUC
END
RETURN @SONUC
END