vb6 - Retrieve next AutoNumber for Access table

Question

I have a table in Microsoft Access/JET that has an AutoNumber field that's set incrementally which serves as the table's primary key. I need to know what the value of the primary key will be for the next inserted record, but I need to know the value before the record is inserted. Using SELECT MAX([ID]) + 1 FROM [TableName]; will not work because records are routinely deleted from the end of the table. (Inserting a new record just to figure out the value is not an option either.)

I know that this is easily done in MySQL by using the SHOW TABLE STATUS command. Is there anything that will let me do this exact same thing for Access/JET using ADO, DAO, VB6 or any other available tools?

Answer 1

You can use ADOX (Microsoft ADO Extensions for DDL and Security) to determine your autonumber field's current "Seed" value.

Public Function NextAutonumber(ByVal pTable As String, _
        ByVal pAutonumField As String) As Long

    Dim cat As Object
    Set cat = CreateObject("ADOX.Catalog")
    Set cat.ActiveConnection = CurrentProject.Connection
    NextAutonumber = cat.Tables(pTable).Columns(pAutonumField).Properties("Seed")
    Set cat = Nothing
End Function

Note this approach could give the wrong result in a multi-user situation ... if another user can sneak an INSERT in between the time you retrieve the next autonumber and you actually do your INSERT. If it's critical, you could verify whether you got the value you expected by checking SELECT @@Identity after the INSERT.