ID: Q158937
The information in this article applies to:
Moderate: Requires basic coding, and interoperability skills.
This article describes a technique you can use to start compacting one or more databases automatically at a scheduled time. You create a small database with a table, a form, and a macro. The table stores the names of the databases you want to compact. The form contains a procedure in the Timer event that starts compacting the databases whose names are in the table. The macro opens the form every time you open the database.
This article assumes that you are familiar with Visual Basic for Applications and with creating Microsoft Access applications using the programming tools provided with Microsoft Access. For more information about Visual Basic for Applications, please refer to your version of the "Building Applications with Microsoft Access" manual.
NOTE: Visual Basic for Applications is called Access Basic in Microsoft Access version 2.0. For more information about Access Basic, please refer to the "Building Applications" manual.
The following example uses a Visual Basic procedure to compact one or more databases, and then to close Microsoft Access when it is finished. You cannot compact the database that is running the procedure, nor can you compact any database that you cannot open exclusively. You must have read and write permissions for the folder where the database you are compacting resides, and you need enough disk space in that folder to store the original and the compacted copies of the database.
1. Create a new blank database called Compact.mdb.
2. Create the following new table in Design view:
Table: DBNames
----------------------------------------------------
Field Name: DBID
Data Type: AutoNumber (or Counter in version 2.0)
Field Name: DBFolder
Data Type: Text
Field Size: 255
Field Name: DBName
Data Type: Text
Field Size 255
Table Properties: DBNames
-------------------------
PrimaryKey: DBID
4. Create a new blank form and set the following properties:
Caption: Compact Databases
Default View: Single Form
Scrollbars: Neither
RecordSelectors: No
NavigationButtons: No
OnTimer: [Event Procedure]
TimerInterval: 60000
type the following procedure:
In Microsoft Access 7.0 and 97:
Private Sub Form_Timer()
'==================================================================
'The Timer event runs this code every minute. It compares your
'system time with the StartTime variable. When they match, it
'begins compacting all databases in the DBNames table.
'==================================================================
Dim StartTime As String
' Set this variable for the time you want compacting to begin.
StartTime = "12:00 AM"
' If StartTime is now, open the DBNames table and start compacting
If Format(Now(), "medium time") = Format(StartTime, _
"medium time") Then
Dim RS As Recordset, DB As DATABASE
Dim NewDBName As String, DBName As String
Set DB = CurrentDb()
Set RS = DB.OpenRecordset("DBNames")
On Error Resume Next
RS.MoveFirst
Do Until RS.EOF
DBName = RS("DBFolder") & "\" & RS("DBName")
' Create a new name for the compacted database.
' This example uses the old name plus the current date.
NewDbName = Left(DbName, Len(DbName) - 4)
NewDbName = NewDbName & " " & Format(Date, "MMDDYY") & ".mdb"
DBEngine.CompactDatabase DBName, NewDBName
RS.MoveNext
Loop
' Close the form, and then close Microsoft Access
DoCmd.Close acForm, "CompactDB", acSaveYes
DoCmd.Quit acSaveYes
End If
End Sub
In Microsoft Access 2.0:
NOTE: In the following sample code, an underscore (_) at the end of a
line is used as a line-continuation character. Remove the underscore
from the end of the line when re-creating this code in Access Basic.
Private Sub Form_Timer()
'==================================================================
'The Timer event runs this code every minute. It compares your
'system time with the StartTime variable. When they match, it
'begins compacting all databases in the DBNames table.
'==================================================================
Dim StartTime As String
' Set this variable for the time you want compacting to begin.
StartTime = "12:00 AM"
' If StartTime is now, open the DBNames table and start compacting.
If Format(Now(), "medium time") = Format(StartTime, _
"medium time") Then
Dim RS As Recordset, DB As DATABASE
Dim NewDBName As String, DBName As String
Set DB = CurrentDb()
Set RS = DB.OpenRecordset("DBNames")
On Error Resume Next
RS.MoveFirst
Do Until RS.EOF
DBName = RS("DBFolder") & "\" & RS("DBName")
' Create a new name for the compacted database.
' This example uses the DBID plus the current date, which
' falls within DOS 8.3 file name limits for DBID = 1 to 99.
NewDBName = RS("DBFolder") & "\" & RS("DBID") & Format(Date, _
"MMDDYY") & ".mdb"
DBEngine.CompactDatabase DBName, NewDBName
RS.MoveNext
Loop
' Close the form, and then close Microsoft Access.
DoCmd Close a_Form, "CompactDB"
DoCmd Quit a_Save
End If
End Sub
7. Create a new macro with the following action:
Action
--------
OpenForm
Action Arguments
--------------------
Form Name: CompactDB
View: Form
Data Mode: Read Only
Window Mode: Normal
9. Open the DBNames table and add a record for each database you want to
compact. Type the full path to the database in the DBFolder field, and
the name of the database itself in the DBName field. For example:
DBID DBFolder DBName
---------------------------------------------------
1 C:\MSOffice\Access\Samples Northwind.mdb
2 \\Servername\Access\Sampapps Nwind.mdb
scheduled to start. The AutoExec macro will automatically open the
CompactDB form. Leave Microsoft Access running with this form open.
At the specified time, compacting begins and when the last database is
done, Microsoft Access closes.
For more information about the Timer event or the TimerInterval property, search the Help Index for "Timer event" or "TimerInterval property."
Keywords : kbprg
Version : 2.0 7.0 97
Platform : WINDOWS
Hardware : x86
Issue type : kbhowtoLast Reviewed: November 20, 1998