A file format that uses HTML and XML to store the connection information. You can view or edit the contents of the file in any text editor.
A standard file format provided by Microsoft Data Links to create file-persistent OLE DB data source object definitions.
Benefits of using a connection file
Using a connection file simplifies the task of deploying related data access pages. Pages that connect to a common data source can share a single connection file. If you move or copy the data source, instead of updating the ConnectionString property of each dependent page, you only need to edit the connection information in the connection file to make the pages point to the right location or database.
Linking a page to a connection file
When creating a data access page, you can choose whether you want to link the page to a connection file or simply use a connection file without creating a link. You can also choose whether you want to use an existing connection file or create a new one.
Linking to a connection file When you establish a link between the connection file and a page, the page's ConnectionFile property is set to the name of the file. Each time you open the page, Access will read the connection file, extract the connection information, and set the ConnectionString property of the page.
Using a connection file without creating a link When creating a page, you can use the contents of a connection file to set the ConnectionString property of the page, but choose not to create a link between the page and the connection file.
Changing the connection information of a page
When a connection file is used Either change the ConnectionFile property of the page to point to a different connection file, or edit the connection file in a text editor. If you choose to edit the connection file, remember that all other pages that use the connection file will also be affected by the changes you make. If you edit the ConnectionString property of a page that is linked to a connection file, the link will be broken and the ConnectionFile property will be set to null.
When a connection file is not used Either create a link between the page and a connection file by setting the ConnectionFile property, or edit the ConnectionString property. When you create a link, Access will automatically set the ConnectionString property based on the contents of the connection file.