Question

I looking for a way to dynamicly add a filter to my statment without using dynamic SQL.

I want to select all computers from a table, but when I pass a computer id to the sp, I want to get only this computer.

Actually I try this on

DECLARE @ComputerFilter AS INT
DECLARE @ComputerID AS INT

SELECT Computername 
FROM   Computer
WHERE  (ComputerID = @ComputerID) OR (@ComputerFilter IS NULL))

But this is 100 times slow then this statment and tooks as long as SELECT * FROM Computer

SELECT Computername 
FROM   Computer
WHERE  ComputerID = @ComputerID

Is there a way to speed this statment up or is there any other way to solve this problem with one select und without dynamic sql?

Answer 1

DECLARE @ComputerID AS INT

SET @ComputerID  = null -- fro all null or just id for one

SELECT Computername 
FROM   Computer
WHERE  ComputerID = ISNULL( @ComputerID, ComputerID  )

When you dont need