sql server - How to write a sql query for different conditions in where clause on demand? -

i have pass different parameters columns code behind, written 15 gridview binding methods 15 columns, avoid set in query.for example if column 1 pick clause , if column 2 pick clause.so how write this?

here example of how create , run dynamic queries

create procedure sp_search     @param1         int = null,     @param2         int = null begin     declare @query_string nvarchar(4000); set @query_string = 'select * table_name 1 = 1 ';          if(@param1 not null)         begin             set @query_string = @query_string + ' , columnname1 = ' + cast(@param1 varchar);         end          if(@param2 not null)         begin             set @query_string = @query_string + ' , columnname2 = ' + cast(@param2 varchar);         end          exec sys.sp_executesql @query_string; end