DataMirror Transformation Moves Toward ODBC

• 09/23/1998

In the past, DataMirror chairman and CEO Nigel Stokes has advocated the use of the APIs that are included in relational database management systems, saying they allowed faster replication of the databases into other formats. He had said that using ODBC for replication and transformation resulted in significant performance lags.

With the recent upgrade of DataMirror’s Transformation Server for Microsoft SQL Server to version 4.1.10, however, ODBC takes center stage.

For one thing, newly added ODBC support allows Transformation Server to refresh SQL Server databases to six ODBC-compliant database managers that hadn’t been available before: Microsoft Access, Sybase Adaptive Server, Sybase SQL Anywhere, Oracle NT Version 7.3, Informix and DB2/NT. All the newly supported databases are targets only, meaning that they can only take data from SQL Server; they can’t send any data back. Previous versions of Transformation Server concentrated on two-way data exchange. The current version continues to support two-way exchange with DB2 on AS/400, another SQL Server on Windows NT, Oracle on Unix or Sybase on Unix.

"A lot of existing customers who were using SQL Server noted a need to replicate data to Microsoft Access and to Informix and to DB2 [on Windows NT] in particular, and the rest just fell into place because it was a relatively straightforward implementation for us using ODBC," says Jason Weir, a DataMirror spokesman.

The upgrade also relies more heavily on ODBC for the two-way transformations between SQL Server databases, says James Pitts, DataMirror product developer for the SQL Server version.

The shift was made for two main reasons, Pitts says. One is that ODBC performance has improved, and the other is that Microsoft Corp. is rapidly moving away from DB-Library, the native API that DataMirror relied on heavily in previous versions of the product. "The end of last year, mid-last year, we started thinking about moving in that direction. We also felt pressure from Microsoft. They were starting to drop support for DB-Library. You don’t want to be caught too offsides," Pitts says.

That said, DataMirror has taken the DLL programs from DB-Library that worked well and embedded them into its own software to improve the fast refresh support, Pitts says. And DataMirror still works exclusively with native APIs in the Transformation Server family products for platforms other than Windows NT.

Janelle Hill, research director for strategic data management service with Gartner Group (Stamford, Conn.), says DataMirror is, for the most part, maintaining its identity as a company that uses native APIs to improve performance. "They are talking natively too," she says. "I think all they’ve done is used a more portable interface to broaden the number of sources they can support."

Hill says one of the most promising databases DataMirror chose to support with the target upgrade was Sybase SQL Anywhere from Sybase Inc. (Emeryville, Calif. www.sybase.com). "SQL Anywhere is one of the few highlights of Sybase these days in that it’s very often used as a mobile database," she says. "If I can replicate data to my mobile users, that’s a good thing."

DataMirror, however, lags behind some of the 25 to 30 other small companies in the market because of the limitations of its data transformation tools, Hill says. "Out of the box they only provide about 20 prebuilt routines. Most of the competition provides hundreds if not thousands. Ardent [Software Inc. (Westboro, Mass., www.ardentsoftware.com)] and Informatica [Corp. (Menlo Park, Calif., www.informatica.com)] have in the range of 1,000 right out of the box," she says.