Optimize Property Example (VB)

This example demonstrates the Field object's dynamic Optimize property. The zip field of the Authors table in the Pubs database is not indexed. Setting the Optimize property to True on the zip field authorizes ADO to build an index that improves the performance of the Find method.

Public Sub Main()  
    On Error GoTo ErrorHandler  

    'To integrate this code  
    'replace the data source and initial catalog values  
    'in the connection string.  

    ' Declare the recordset and connection variables.  
    Dim Cnxn As ADODB.Connection  
    Dim rstAuthors As ADODB.Recordset  
    Dim strCnxn As String  
    Dim strSQLAuthors As String  

     ' Open connection.  
    strCnxn = "Provider='sqloledb';Data Source='MySqlServer';" & _  
        "Initial Catalog='Pubs';Integrated Security='SSPI';"  
    Set Cnxn = New ADODB.Connection  
    Cnxn.Open strCnxn  

     ' open recordset client-side to enable index creation.  
    Set rstAuthors = New ADODB.Recordset  
    rstAuthors.CursorLocation = adUseClient  
    strSQLAuthors = "SELECT * FROM Authors"  
    rstAuthors.Open strSQLAuthors, Cnxn, adOpenStatic, adLockReadOnly, adCmdText  
     ' Create the index.  
    rstAuthors!zip.Properties("Optimize") = True  
     ' Find Akiko Yokomoto  
    rstAuthors.Find "zip = '94595'"  

     ' Show results.  
    Debug.Print rstAuthors!au_fname & " " & rstAuthors!au_lname & " " & _  
             rstAuthors!address & " " & rstAuthors!city & " " & rstAuthors!State  
    rstAuthors!zip.Properties("Optimize") = False  'Delete the index.  

    ' Clean up.  
    Set rstAuthors = Nothing  
    Set Cnxn = Nothing  
    Exit Sub  

    ' clean up  
    If Not rstAuthors Is Nothing Then  
        If rstAuthors.State = adStateOpen Then rstAuthors.Close  
    End If  
    Set rstAuthors = 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  

See Also

Field Object
Optimize Property-Dynamic (ADO)