i have a problem and it's hard to explain but don't know the solution for many years,pls help me...

A is viewing database from datagrid.
after that
B inserting a new data to database from different computer.
A still looking datagrid from database before updated.

if he don't click refresh or using timer how can the datagrid automatically refresh the data from database without using button or timer.
i don't like using timer cause it eat resources a lot.

thx
sorry bad english