Display query results in Combobox2 based on the selected value of Combobox1

Hi,
I have two comboboxes,say cb1 and cb2. cb1 has 3 values,say dept1,dept2,dept3. When the value of cb1 changes,I want to retrieve values from oracle database based on the value of dept1, i.e,if I select dept1,i need to get 'select name from table1 where dept="dept1". If the selected value was dept2,then the query should be like this,'select name from table1 where dept="dept2".Then,cb2 should display all the names resulting from query.How can I do this in an asp page. Pls help. I am very new to classic asp and vbscript