SQL Server Stored Procedure select - sql

Question

I can't figure out how to set the values if Power, ChangeRate, and Type are null. I still want it to return rest of the values even if those are not in the database.
ALTER PROCEDURE dbo.up_getTestData
(#Chip int)
AS
DECLARE #Type char(2), #ChangeRate real, #Power bit
SELECT #Type = Type
FROM Spectrum
WHERE ChipID = #Chip
IF(#Type is null)
//SET #Type = 'NA'
//or Go to the bottom statement ??
SELECT #ChangeRate = ChangeRate
FROM TempCycle
WHERE ChipID = #Chip
IF(#ChangeRate is null)
//Go to the bottom statement ??
//SET #ChangeRate = '0.0'
SELECT #Power = Power
FROM TempCycle
WHERE ChipID = #Chip
IF(#Power is null)
// I want it to still go the bottom statement. I put just return
// but that's not right since it wouldn't return anything than??
// or I did SET #Power = 'false'
ELSE
SELECT
Chips.Chip_ID AS ChipID,
Chip_Number, Test_Module.ModuleTypeID,
Test_Module.PID, Test_Module.Component1, Test_Module.Component2,
Test_Module.Parameter1, Test_Module.Parameter2, Test_Module.Parameter3,
Test_Module.Parameter4, Test_Module.Parameter5,
Test_Module.Parameter6, Spectrum.Type, TempCycle.Power, TempCycle.ChangeRate
FROM
Chips
INNER JOIN
Test_Module ON Chips.Chip_Number = Test_Module.Module_Name
INNER JOIN
Spectrum ON Test_Module.ModuleSpec_TestID = Spectrum.TestID
INNER JOIN
TempCycle ON Test_Module.ModuleTemp_TestID = TempCycle.TestID
WHERE
Chip_ID = #Chip
RETURN

Answer 1

I think all you need is coalesce (or ISNULL):
SELECT
Chips.Chip_ID AS ChipID,
Chip_Number,
Test_Module.ModuleTypeID,
Test_Module.PID,
Test_Module.Component1,
Test_Module.Component2,
Test_Module.Parameter1,
Test_Module.Parameter2,
Test_Module.Parameter3,
Test_Module.Parameter4,
Test_Module.Parameter5,
Test_Module.Parameter6,
coalesce(Spectrum.Type, 'NA') as Type,
coalesce(TempCycle.Power, 'false') as Power,
coalesce(TempCycle.ChangeRate, '0.0') as ChangeRate
FROM
Chips INNER JOIN Test_Module
ON Chips.Chip_Number = Test_Module.Module_Name
LEFT OUTER JOIN Spectrum
ON Test_Module.ModuleSpec_TestID = Spectrum.TestID
LEFT OUTER JOIN TempCycle
ON Test_Module.ModuleTemp_TestID = TempCycle.TestID
WHERE
Chip_ID = #Chip