I used the format that you sent to me:

prm=cmdInsert.Parameters.Add("@Key",ds.Tables("a").Columns("Key"))

But I encounter an error:

---> Index (zero based) must be greter than or equal to zero and less than the size of the argument list.

I think the this error was caused by the column("Key"). Because in this column thier are many rows record involved. Remember that i used data grid..