Microsoft Host Data Replicator is a companion product to Microsoft SNA Server and is used for high-performance replication of data between IBM DB2 and Microsoft SQL Server computers.
Whether the enterprise uses an AS/400, an RS/6000, or a mainframe system, Microsoft Host Data Replicator (HDR) will help you implement emerging technology solutions for Internet and intranet publishing, electronic commerce, data warehousing, or data mining. Microsoft (HDR) directly enables these solutions through efficient, bidirectional snapshot replication of data between Microsoft SQL Server and multiplatform DB2 databases.
One way data replication is frequently used for decision support. Typically, these applications do not need the most up-to-date information. For example, when studying monthly or annual business trends, it usually isn't essential to have data that is current to the second. Also, record-by-record access to data on IBM hosts must compete with production data processing. Therefore, it is often useful to transfer a database to a local machine, reducing the burden on the production host system. After transferring a copy of the host data to SQL Server in Windows NT, analysts can read the data many times on their local systems without affecting host processing.
Another critical use of host data replication is data warehousing. Often, production data processing systems do not store in DB2 historical data that may be valuable for trend analysis and similar decision-support applications. One solution is to schedule regular Host Data Replicator replications from DB2 to SQL Server to accumulate needed historical data. Over time, this replication creates a data warehouse that is valuable for many kinds of analysis.
In many cases, applications on local machines may only need a subset of data from a given database. Host Data Replicator provides convenient dialog boxes that let users select parts of the database to replicate. Users may limit the transfer of data to particular rows or particular columns, or both. For example, an analyst may wish to look at sales data only for the July and August and would select only the rows of the database corresponding to these months. Similarly, an analyst may wish to look only at sales of a particular product and would select only the columns of the database corresponding to this product.
Once selected, the database subset in SQL Server is easier to manage and use than the huge database superset in DB2. Most analysts running decision-support applications understand and appreciate the value of so called "subsetting" and use the technique frequently.
Subsetting is valuable for production data processing applications, as well. For example, a desktop sales application might use Host Data Replicator to download every day a subset of the company’s price list. The application might need prices of only certain products (vertical subsetting) and only current pricing (horizontal subsetting).
Microsoft Host Data Replicator provides ease of use and comprehensive administration by providing advanced tools for easy system setup and centralized graphical administration of all replication functions, including filtering, scheduling, and gathering statistics. The following information provides a short explanation of some of the most frequently used utilities and system features.