Where statement with variables

From: Phil (Phil_at_discussions.microsoft.com)
Date: 01/31/05 

Date: Mon, 31 Jan 2005 01:21:02 -0800

Hi All,

Just a quick question for anyone, I have a stored procedure that uses a lot
of variables in a where statement, the only problem with this is it's very
slow, I am just listing them something like this

WHERE
AND (tblSurvey.disposal_method = @disposalRoute OR @disposalRoute = 'null')
AND (tblSurvey.air_conditioning = @airCon OR @airCon = 'null')
AND (tblSurvey.documentation = @documentation OR @documentation = 'null')

is there a better way of writting this statement to speed it up.

Thanks for your help.

Regards Phil