Data Access and Transactions

RDO

The Remote Data Objects (RDO) were specifically designed to access remote ODBC relational data sources, and to add a thin object layer to the ODBC application programming interface (API). RDO performance is, in most cases, close to that of the ODBC API.

RDO was specifically designed to deal with remote, intelligent data sources (such as SQL Server or Oracle, as opposed to ISAM databases), so it does not support some of the DAO table-based interfaces or Dynamic Data Exchange (DDE). RDO can execute ordinary table-based queries, but it is especially adept at building and executing queries against stored procedures. It also handles all types of result sets including those generated by multiple result set procedures, those returning output arguments, and those requiring complex input parameters. RDO 2.0 provides a high level of control over remote data sources, so it is not necessary to expose the underlying ODBC handles in order to manipulate the data sources, except in the most unusual cases. It also can create client cursors to manage “disconnected” result sets.

Once again, newer technologies have surpassed older ones. For example, ADO provides equivalent functionality and performance to RDO, with an easier-to-use object model; ADO can also access a much larger variety of data stores.