RAISING AN EVENT WHEN DATABASE TABLE UPDATES

hi all,

i want to raise an event when database table updates.For eg : if a price of a material has been changed then i have to raise an event and run the abap program in back ground.i know transaction SM62 to create event, i dont know about transaction SM64. please give me the procedure how to solve this problem. i dont know work flow. please give me a sample code how to raise event.

thanka and regards

suresh