How to Update the access table rows with relative rows from another table

Hello Kschuler, Thanks for you comments....
I need to update table rows by another table row by reference same id's (Please go thru my question) and i have the below code to fetch the required values to update those values in another table.

Dim conn123 As New OleDbConnection("My connection string")

Dim Query As String = "SELECT (B.WidrawAmt) AS test FROM CashWidrawReg A INNER JOIN CashWidrawTran B on A.WRegID = B.WRegID WHERE A.WRegID = 15"

Dim Cmd As New OleDbCommand(Query, conn123)

Dim Dr As OleDbDataReader
Dim outPutString As String = ""

conn123.Open()

Dr = Cmd.ExecuteReader
With Dr
If .HasRows = True Then
While .Read
outPutString += .Item(0).ToString & ","
End While
End If
End With
Dr.Close()

Output
10000,500,

And I also update the table using the below query...

Dim conn1 As New OleDbConnection("My Connection String")

Dim query1 As String = "UPDATE CashDepositTran SET CashDepositTran.WidrawAmt = CashDepositTran.WidrawAmt - '" & outPutString & "' WHERE CashDepositTran.CTranID IN (1,2)"

Dim Cmd1 As New OleDbCommand(query1, conn1)
conn1.Open()
With Cmd1
.ExecuteNonQuery()
End With
Cmd1.Dispose()
conn1.Close()

After excuting the UPDATE query its updating by concatenate the output values.

Table: CashDepositTran (Before UPDATE Query)
CTranID | CRegID | CashDepDate | UserID | DepAmt | WidrawAmt
1 | 1 | 09/Mar/2013 | 123 | 10000 | 10000
2 | 1 | 09/Mar/2013 | 123 | 500 | 500

10000500 and updating in each rows as below

Table: CashDepositTran (After UPDATE Query)
CTranID | CRegID | CashDepDate | UserID | DepAmt | WidrawAmt
1 | 1 | 09/Mar/2013 | 123 | 10000 | -9990500
2 | 1 | 09/Mar/2013 | 123 | 500 | -10000000

Here the values are getting concatenate and getting updated.