Manipulating data from tables i various ways?

[janero]

I am a superclumsy programmer i .net so far, and i need tips!
I made this function to get «saldo» :

Shared Function HentSaldo(ByVal saldo As Double) As Double
Dim cnn1 As New ADODB.Connection()
Dim rst1 As New ADODB.Recordset()
cnn1.Open("Provider=Microsoft.Jet.OLEDB.4.0;Data _ Source=C:\VB\Proj.mdb;")
'open recorset for rows
Dim str1 As String = "Select Sum(Debit),Sum(Kredit) From Balanse"

With rst1
.ActiveConnection = cnn1
.Open(str1, , _
ADODB.CursorTYpeEnum.adOpenForwardOnly, _
ADODB.LockTypeEnum.adLockReadOnly)
End With
Dim s_debit As Double
Dim s_kredit As Double
Dim s_saldo As Double
Do Until rst1.EOF
s_debit = CDbl(rst1("Debit").Value)
s_kredit = CDbl(rst1("Kredit").Value)
s_saldo = s_debit - s_kredit
rst1.MoveNext()
Loop

Return s_saldo
End Function

And this function return either nothing or errormessage om the connection.
And i have tryed to use classes, eks:

Public Sub getKredit()

Dim conn As New OleDb.OleDbConnection(connstr)
Dim kreditdap As New OleDb.OleDbDataAdapter("Select Kredit from_ SumKreditDebit", conn)
conn.Open()
kreditdap.Fill(dsKredit, "SumKreditDebit")
conn.Dispose()
dsKredit.Dispose()
conn.Close()

End Sub

This (SumKreditDebit) is a query and give me nothing in return when i call it.
Do anyone have som examples in how to take values in tables an manipulate then in a simple way?

[kenobewan]

Your query returns nothing as you haven't given it enough information, like an ID... Here is an article that may help:
Server-Side Data Access

[janero]

Your query returns nothing as you haven't given it enough information, like an ID... Here is an article that may help:
Server-Side Data Access

This i should know...Thank you for your help:-)