Question

these are the variables i am passing to some method where i need to write some sql query like

string cmd = @"select *
from students_tbl
where
     course_id=@courseId and branch_id=in(+" branchId "+)
and passout_year>=@passoutYear
and current_backlog>=@currentBacklog
and gender=@gender
and eGap<=@eGap
and first_year_percent>=@firstyearPercent
and second_year_percent>=@seconYearPercent
and third_year_percent>=@thirdyearPercent";

and so on but problem is that few of these parameters are optional means for those variable
there value is null so i don’t want to include those parameter in query
so how should i eliminate those null variable i am not getting how should i write query to solve this issue

those parameter are random nothing fix when they will be null because hey are optional
so how should i write query by using only not null parameter

Answer 1

Just add an is null check before your comparison, which will short-circuit if the input parameter value is null, e.g.:

where (@currentBacklog is null or current_backlog >= @currentBacklog)