gistfile1.rb

    params[:page] ||= 1
	params[:order] ||= 'date'
	
	conditions = [""]
	
	if !params[:date_since].nil? and !params[:date_since].empty?
	  conditions[0] += "? < date AND "
	  conditions += [params[:date_since]]
	end
	
	if !params[:date_until].nil? and !params[:date_until].empty?
	  conditions[0] += "? < date AND "
	  conditions += [params[:date_until]]
	end
	
	if !params[:name].nil? and !params[:name].empty?
	  conditions[0] += "employees.name LIKE ? AND "
	  conditions += [params[:name]]
	end
	
	if !params[:serial_number].nil? and !params[:serial_number].empty?
	  conditions[0] += "cards.serial_number = ? AND "
	  conditions += [params[:serial_number]]
	end
	
	conditions[0] += "TRUE"