How to fire Trigger

dear friends
i have one table in sql. so i want to perform a one action that if i use select * from my_tablename .so 
 that query should be printed in gridview . (that i knw how to do). but the problem is once the column 
printed in gridview . that time automaticlly one extera column should be added in that gridview containg  CHECKBOXES. and once i check that checkbox
and press a button click . that checkbox row should be added in new table.(using trigger)
plz help me