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StayInSync Property Example (VB)

This example demonstrates how the StayInSync property facilitates accessing rows in a hierarchical Recordset.

The outer loop displays each author's first and last name, state, and identification. The appended Recordset for each row is retrieved from the Fields collection and automatically assigned to rstTitleAuthor by the StayInSync property whenever the parent Recordset moves to a new row. The inner loop displays four fields from each row in the appended recordset.

'BeginStayInSyncVB  
Public Sub Main()  
    On Error GoTo ErrorHandler  
  
    Dim Cnxn As ADODB.Connection  
    Dim rst As ADODB.Recordset  
    Dim rstTitleAuthor As New ADODB.Recordset  
    Dim strCnxn As String  
  
    ' Open the connection with Data Shape attributes  
    Set Cnxn = New ADODB.Connection  
    strCnxn = "Provider=MSDataShape;Data Provider='sqloledb';Data Source='MySqlServer';" & _  
        "Initial Catalog='Pubs';Integrated Security='SSPI';"  
    Cnxn.Open strCnxn  
  
    ' Create a recordset  
    Set rst = New ADODB.Recordset  
    rst.StayInSync = True  
    rst.Open "SHAPE {select * from Authors} " & _  
                   "APPEND ( { select * from titleauthor} AS chapTitleAuthor " & _  
                   "RELATE au_id TO au_id) ", Cnxn, , , adCmdText  
  
    Set rstTitleAuthor = rst("chapTitleAuthor").Value  
    Do Until rst.EOF  
        Debug.Print rst!au_fname & " " & rst!au_lname & " " & _  
                   rst!State & " " & rst!au_id  
  
        Do Until rstTitleAuthor.EOF  
            Debug.Print rstTitleAuthor(0) & " " & rstTitleAuthor(1) & " " & _  
                   rstTitleAuthor(2) & " " & rstTitleAuthor(3)  
            rstTitleAuthor.MoveNext  
        Loop  
  
        rst.MoveNext  
    Loop  
  
    ' Clean up  
    rst.Close  
    Cnxn.Close  
    Set rst = Nothing  
    Set Cnxn = Nothing  
    Exit Sub  
  
ErrorHandler:  
    ' Clean up  
    If Not rst Is Nothing Then  
        If rst.State = adStateOpen Then rst.Close  
    End If  
    Set rst = Nothing  
  
    If Not Cnxn Is Nothing Then  
        If Cnxn.State = adStateOpen Then Cnxn.Close  
    End If  
    Set Cnxn = Nothing  
  
    If Err <> 0 Then  
        MsgBox Err.Source & "-->" & Err.Description, , "Error"  
    End If  
End Sub  
'EndStayInSyncVB  

See Also

Fields Collection (ADO)
Recordset Object (ADO)
StayInSync Property