Data Access Objects (DAO) is designed primarily for use with local and ISAM (Indexed Sequential Access Method) data sources created through applications such as Microsoft Access, Microsoft FoxPro, and Borland dBASE. Although DAO can be used to connect to ODBC data sources, RDO and ADO provide more powerful options for such data. However, DAO is the oldest of the three technologies, giving it the advantage of being familiar to many Visual Basic programmers. As a result, DAO is also frequently found in existing applications, and applications created with older versions of Visual Basic.
If you are adding the Report Designer Component to a Visual Basic application that already uses DAO, or if you are connecting to a local data source such as an Access or dBASE file, you should consider using DAO to design your reports. Experienced Visual Basic programmers who are familiar with the DAO object model may also want to stick with a known technology. However, if you are working with ODBC or other remote data sources, RDO and ADO may be a better solution.
Once you design your report in the Report Designer Component, information about the connection to your DAO data source is stored with the report, and cannot be accessed directly. However, you can change the data displayed by a report by changing the data source at runtime using the SetDataSource method. A DAO Recordset object may be passed to the report through this method. Keep in mind, though, the Recordset must have fields identical to those in the original data source used at design time.
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