If your application requires access to a relational database on the mainframe, you can use the Microsoft Host Data Replicator (HDR) to copy relational data between the mainframe database and the SQL Server database.
HDR can move data in either direction between a server and a mainframe. You can configure it to perform these data copies at scheduled intervals, or on demand. If an organization already uses IBM's DB2 database technology and Microsoft SQL Server, you can use the Host Data Replicator in a data warehousing application to move data rapidly between the distributed SQL Server database and DB2 for large applications or specific queries. You can also use it to transfer data from DB2 to online SQL server repositories for Web applications or to upload data from the SQL Server to a mainframe database.
HDR is designed to support several DB2 database configurations, including:
The primary advantage of using the Host Data Replicator to support mainframe relational database access is that it's very fast when compared to direct access using an ODBC driver. A disadvantage is that you must use additional hardware and software to configure the replication server.
For More Information For more information on using an ODBC driver to access a mainframe relational database, see Accessing a Mainframe Database Using ODBC in this chapter.
HDR provides an important architectural option for your enterprise application. The following topics will acquaint you with HDR and how it works.
| Section | Description |
| An Overview of the Host Data Replicator Architecture | Describes how HDR fits into a SQL Server and mainframe database architecture. |
| Using HDR Snapshot Replication | Describes how HDR copies data to and from the mainframe relational database. |
| Working with Host Data Replication | Explains how to customize data replication using various HDR features and configuration options. |
| Types of Applications That Benefit from HDR | Defines some typical applications that should use HDR. |