Cache Refreshing

The PageTimeout setting determines how long Microsoft Jet waits before checking to see if other users have made changes to the database. If changes have been made, Microsoft Jet refreshes the data in its cache.

Note Refreshing data in the cache is equivalent to pressing F9 while viewing a table or query in Microsoft Access, or using the Refresh method in DAO code.

The default PageTimeout setting is 5,000 milliseconds. Decreasing this setting increases the amount of time spent reading from the disk, thus impairing performance, but can make the data available to the user more current. In Microsoft Access 97, the setting in the Refresh Interval box on the Advanced tab of the Options dialog box (Tools menu) overrides the PageTimeout setting.

Tip You can override the PageTimeout setting and refresh the Microsoft Jet cache by using the dbRefreshCache argument of the Idle method in DAO code. This allows users to see other users’ changes immediately. For more information on the Idle method, see “Programmatically Refreshing the Microsoft Jet Cache” later in this chapter.