changing data of datagrid in run time

hello everybody
i have a problem in changing the data displayed in datagrid and i have use the following code for this purpose but it doesn't work:
dim SQL as string
SQL = " SELECT * FROM Tablename WHERE no = 12 "
ADODC1.Recordsource = SQL
ADODC1.Refresh
The code above deals with a table ,and this table is a part of a database with three tables connected together by relationships.
I am asking if the relationships are making a problem or what?
If anyone can help me as faster as possible i'll be very greateful