How to change Data type of Grid column at runtime..??

Hi ,

I have taken a "Grid" control,and i have pass a query "Select itemcode Qunatity,linetotal From PDN1" in the ExecuteQuery

method of Grid it displaying the data,

but the problem is i want to change the Datatype of this column from "FLOAT" to "db_Quantity" according to the SAP standerd

of decimal places(like 2 or 3 decimal place which the customer maintain) after executing Query.

How can we achieve this please guide me what to do...

Thanks

Sandesh