How to prevent database bloat after you use Data Access Objects (DAO)

Article translations Article translations
Article ID: 289562 - View products that this article applies to.
This article was previously published under Q289562
Moderate: Requires basic macro, coding, and interoperability skills.

This article applies only to a Microsoft Access database (.mdb).

For a Microsoft Access 2000 version of this article, see 209847.
For a Microsoft Access 97 version of this article, see 186311.
Expand all | Collapse all

SYMPTOMS

A Microsoft Access database has begun to bloat (or grow rapidly in size) after you implement Data Access Objects (DAO) to open a recordset.

CAUSE

If you do not release a recordset's memory each time that you loop through the recordset code, DAO may recompile, using more memory and increasing the size of the database.

RESOLUTION

To avoid consuming unnecessary resources and increasing database size, use the Close method of the Recordset object to explicitly close the recordset's memory when you no longer need the recordset.

If the database has increased in size because you did not use the Close method of the Recordset object, you can reduce the size of the database by running the Compact and Repair utility (on the Tools menu).

MORE INFORMATION

When you create a Recordset (or a QueryDef) object in code, explicitly close the object when you are finished. Microsoft Access automatically closes Recordset and QueryDef objects under most circumstances. However, if you explicitly close the object in your code, you can avoid occasional instances when the object remains open. The following steps show you how to use DAO to close a Recordset or QueryDef object.
  1. Start Microsoft Access.
  2. Open the sample database Northwind.mdb.

    NOTE: The sample code in this article uses Microsoft Data Access Objects. For this code to run properly, you must reference the Microsoft DAO 3.6 Object Library. To do so, click References on the Tools menu in the Visual Basic Editor, and make sure that the Microsoft DAO 3.6 Object Library check box is selected.

  3. Copy the following code to a new module. The following sample code opens and closes a Recordset and a QueryDef object, and displays both Recordset and QueryDef information within message boxes.
    Option Compare Database
    Option Explicit
    
    Sub subCloseObjects()
        Dim db As DAO.Database
        Dim rs As DAO.Recordset
        Dim qd As DAO.QueryDef
    
        Set db = CurrentDb
        Set rs = db.OpenRecordset("Employees", dbOpenTable)
        Set qd = db.QueryDefs("Invoices")
    
        rs.MoveLast    'Move to the last record in the Recordset.
    
        MsgBox "The Employees Recordset is open." & vbCrLf & _
               "The last Employee ID is " & rs![EmployeeID] & "."
        MsgBox "The Invoices query definition is open." & vbCrLf & _
               "The first field in the query is " & qd.Fields(0).Name
    
        'Explicitly close the Recordset and QueryDef objects.
        rs.Close
        qd.Close
    End Sub
    					
  4. Run the subCloseObjects routine.

Properties

Article ID: 289562 - Last Review: April 11, 2007 - Revision: 6.1
APPLIES TO
  • Microsoft Office Access 2007
  • Microsoft Office Access 2003
  • Microsoft Access 2002 Standard Edition
Keywords: 
kbprogramming kbvba kbprb KB289562

Give Feedback

 

Contact us for more help

Contact us for more help
Connect with Answer Desk for expert help.
Get more support from smallbusiness.support.microsoft.com