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How to: Move Through a DAO Recordset

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A Recordset object usually has a current position, most often at a record. When you refer to the fields in a Recordset, you obtain values from the record at the current position, which is known as the current record. However, the current position can also be immediately before the first record in a Recordset or immediately after the last record. In certain circumstances, the current position is undefined.

You can use the following Move methods to loop through the records in a Recordset:

  • The MoveFirst method moves to the first record.

  • The MoveLast method moves to the last record.

  • The MoveNext method moves to the next record.

  • The MovePrevious method moves to the previous record.

  • The Move method moves forward or backward the number of records you specify in its syntax.

You can use each of these methods on table-type, dynaset-type, and snapshot-type Recordset objects. On a forward-only-type Recordset object, you can use only the MoveNext and Move methods. If you use the Move method on a forward-only-type Recordset, the argument specifying the number of rows to move must be a positive integer.

The following code example opens a Recordset object on the Employees table containing all of the records that have a Null value in the ReportsTo field. The function then updates the records to indicate that these employees are temporary employees. For each record in the Recordset, the example changes the Title and Notes fields, and saves the changes with the Update method. It uses the MoveNext method to move to the next record.

Sub UpdateEmployees() 
 
Dim dbsNorthwind As DAO.Database 
Dim rstEmployees As DAO.Recordset 
Dim strSQL As String 
Dim intI As Integer 
 
On Error GoTo ErrorHandler 
 
   Set dbsNorthwind = CurrentDb 
 
   ' Open a recordset on all records from the Employees table that have 
   ' a Null value in the ReportsTo field. 
   strSQL = "SELECT * FROM Employees WHERE ReportsTo IS NULL" 
   Set rstEmployees = dbsNorthwind.OpenRecordset(strSQL, dbOpenDynaset) 
 
   ' If the recordset is empty, exit. 
   If rstEmployees.EOF Then Exit Sub 
 
   intI = 1 
   With rstEmployees 
      Do Until .EOF 
         .Edit 
         ![ReportsTo] = 5 
         ![Title] = "Temporary" 
         ![Notes] = rstEmployees![Notes] & "Temp #" & intI 
         .Update 
         .MoveNext 
         intI = intI + 1 
      Loop 
   End With 
 
   RstEmployees.Close 
   dbsNorthwind.Close 
 
   Set rstEmployees = Nothing 
   Set dbsNorthwind = Nothing 
 
   Exit Sub 
 
ErrorHandler: 
   MsgBox "Error #: " & Err.Number & vbCrLf & vbCrLf & Err.Description 
End Sub

Note

The previous example is provided only for the purposes of illustrating the Update and MoveNext methods. For optimal performance, it is recommended that you perform this bulk operation with a SQL UPDATE query.