i exclude records having userid null if there @ least 1 record has value in it.
if exists (select * @mysavedsearches userid not null) select ssm.* xyztable ssm join @mysavedsearches mysearches on ssm.uniqueid = mysearches.uniqueid , mysearches.userid not null else select ssm.* xyztable ssm join @mysavedsearches mysearches on ssm.uniqueid = mysearches.uniqueid with above query able desired result, somehow feel it's not correct way.
get count variable , check inside where:
declare @cnt int select @cnt = count(*) @mysavedsearches userid not null select ssm.* xyztable ssm join @mysavedsearches mysearches on ssm.uniqueid = mysearches.uniqueid , ((@cnt > 0 , mysearches.userid not null) or (@cnt = 0)) 