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Modifying Important Properties of a Data Access Page
Just as a form or report has properties, so does a data access page. Many of the properties are similar to those of forms and reports. This section discusses the most important properties.To modify the properties of a data access page, you must first make sure that you select the page. The easiest way to select the page is to click its title bar. Among the most important properties of a data access page are its data properties. These appear in Figure 26.25, and the most important properties are discussed here.
Figure 26.25. The data properties of a data access page allow you to control the behavior of the data underlying the data access page.
The ConnectionFile Property
The ConnectionFile property designates the name of the Office Database Connection (.odc) file or the Microsoft Data Link (.udl) file that connects a data access page to its data source. Using an ODC or UDL file, you can easily modify the source of the data underlying a data access page without having to make changes to the page itself.To enter the ConnectionFile property, click the ellipsis within the property. The Select Data Source dialog box appears (see Figure 26.26). Here you can select an existing ODC or UDL file, or create a new file.
Figure 26.26. The Select Data Source dialog box allows you to select an existing ODC or UDL file, or to create a new one.
To create a new file, follow these steps:
Figure 26.27. The Data Connection Wizard walks you through the steps to create an ODC file.
Figure 26.28. The Data Link Properties dialog box allows you to choose a data provider.
Figure 26.29. The Data Connection Wizard connects to the database and shows you all tables and queries contained in the database.
Figure 26.30. The Data Connection Wizard prompts you to name the ODC file. You can also enter a description to assist people when selecting an existing ODC file.
The ConnectionString Property
The ConnectionString property sets an ActiveX Data Objects (ADO) connection string to be used to connect to a database. The string contains all information required to connect to the data source underlying the page.
The DataEntry Property
Another important property is the DataEntry property. By default, the DataEntry property is False. This means that, when the data access page is viewed from within Microsoft Access or within a browser, all records in the underlying data source are available. When changed to True, records can be added, but existing data cannot be seen (see Figure 26.31).
Figure 26.31. The DataEntry property allows you to specify whether existing records are available.
The MaxRecords Property
The MaxRecords property allows you to designate the number of records that a connection sends to the local computer. If you do not set this property properly, extremely large volumes of data can travel over the Internet or over an intranet to the user's browser. This can cause severe performance problems. It is therefore a good idea to set this number to the maximum number of records that you feel are appropriate for a user to retrieve.
The RecordsetType Property
You can set the RecordsetType property to dscUpdatableSnapshot or to dscSnapshot. With dscUpdatableSnapshot the data in the resulting data access page can be edited. If you select dscSnapshot, the data is rendered view-only.
The UseRemoteProvider Property
The UseRemoteProvider property determines whether the data source control uses the Microsoft Remote Data Services provider for data connections. This property can be set to True only for pages that are read from a Microsoft Internet Information Server (IIS) using an HTTP or HTTPS (secure) address. When used, the Microsoft Remote Data Services provider fetches data by passing the HTTP or HTTPS request to Microsoft IIS. IIS makes the OLE DB connection to the database.
