Data, data everywhere, looking for a link

Data, data everywhere, looking for a link – Microsoft’s Open Database Connectivity standard

Janet Butler

Organizing shifting from mainframe environments to client/server networks do so for various reasons. One is to better get data in the hands of end users. However, client/server, by nature, generates disparate databases. For IS, that means new headaches when end users want to be able to access them all from their desktops.

Ideally, “the fewer databases you have, the better,” said Peter Kastner, group vice president of Aberdeen Group Inc., Boston. But in the real world, he said, companies are forced to provide access to multiple databases because they house critical information. “Tying together different databases is a necessary evil,” he said.

Kastner and others maintain that standards remain the best hope for a strong link between multivendor, DBMSs. The industry will take a major step toward such standardization when Microsoft’s Open Database. Connectivity (ODBC) becomes fully compliant with X/Open’s latest Call-level Interface (CLI) specifications some time near year end. The original CIA, spec was released in 1991 by the SQL Access Group (SAG), a vendor consortium now under the X/Open umbrella.

The SAG CLI, said Dean Adams, manager of X/Open’s database technology program, is the “preferred method of [database] access.” The first two versions of ODBC were based on the original SAG CLI. ODBC 3.0 , announced in February and due for release in September, will be aligned with an updated X/Open CLI. Observers also expect Version 3.0 to comply with new Ansi/ISO CLI specifications. Microsoft will incorporate ODBC 3.0 into its OLE (Object Linking and Embedding) architecture.

Kastner calls ODBC the “unsung hero of 1995.” ODBC is already a de facto standard, growing far beyond Microsoft’s original plan to come up with a Windows-only specification. It functions as a standard interface between the server and the client application to provide access to databases with different SQL dialects. Once ODBC complies fully with the X/Open specification, support for the technology should grow rapidly.

In 1994 Microsoft licensed the ODBC specifications to Visigenic Software Inc., San Mateo, Calif., to develop versions for non-Microsoft operating systems. So far Visigenic has made ODBC drivers available on Macintosh and Unix platforms. The Visigenic ODBC product line comprises the ODBC Software Developers’ Kit, ODBC Driver Set, and ODBC Test Suites.

Microsoft is also working closely with Intersol Inc., Rockville, Md., whose DataDirect technology has been licensed by more than 60 applications vendors to add support for multiple database systems.

Bert Simonis, senior director of mainframe integration technologies at Oracle Corp., Redwood Shores, Calif., predicts ODBC will gather momentum over the next year as it gains performance and functionality. Oracle, he said, “will ride that wave.”

Oracle licenses ODBC technology from Visigenic to embed in its Transparent Gateway product. Oracle also licenses Intersolv’s DataDirect drivers for access to CA-OpenIngres from Computer Associates International Inc., Islandia, N.Y., Informix from Informix Software lnc., Menlo Park, Calif., and SQL Server from Sybase Inc., Emeryville, Calif.

IBM has likewise jumped on the ODBC bandwagon, signing an agreement with Visigenic to jointly develop drivers for the DB2 relational database family. IBM’s ODBC drivers will provide access to DB2 running on MVS, VM, VSE, OS/400, OS/2 and AIX platforms. Visigenic will bundle the DB2 drivers in its AIX, OS/2 and Windows ODBC Driver Set products.

When asked about Microsoft’s reputation for giving less than full attention to standards processes, X/Open’s Adams said Microsoft is “no sloucher on this one.” In fact, he said, Microsoft has been very active in developing the new CLI specification.

As to claims that ODBC has mediocre performance, Aberdeen’s Kastner said that was true of the first version. However, he said, ODBC 2.0 performance is within 5% of native database connection. Improvements are due in part to enhancements in the driver manager.

At Oracle, they found that ODBC performed well when they looked at it on Unix, said Simonis. They did not run it on Windows, which is where most users have reported performance problems.

IBM, with its Distributed Relational Database Architecture (DRDA), has set its sights on earning an X/Open blessing as well. George Zagelow, product manager for data warehousing solutions at IBM’s database development lab in Santa Teresa, Calif., said DRDA is a way to “leverage the strength of DB2 MVS as a data source.” There’s “symmetry in offering DRDA to reach interesting data sources like Oracle and Sybase,” he said.

By offering DRDA to X/Open for branding, IBM hopes to encourage vendors who are uncomfortable with DRDA because they view it as an IBM-centric solution. With a standards body running the show, said Zagelow, DRDA will have a better chance of being viewed as “neutral.” IBM supports an X/Open approval of ODBC as the database client interface standard, with DRDA as the server interface.

IBM’s effort to establish DRDA as a server standard may take a bit longer than company officials would like. X/Open must first determine what DRDA has to offer, and whether the rest of the database community is interested, said X/Open’s Adams.

“When X/Open takes on specifications, anyone should be able to pick up the specs [and have] everything they need for independent implementation. If it’s not there, it’s an issue for X/Open,” he said.

X/Open was involved in Remote Data Access (RDA), an application-level protocol through which different servers and clients could exchange transactions. However, said Adams, RDA became tainted with the ISO mark.” When ISO failed in its competition with TCP/IP over protocol specifications, RDA lost support.

What’s the vendor interest in providing products that support DRDA? Thus far, said Adams, there have been “more intentions announced than products in the [DRDA] marketplace.” And most of those involve connections to IBM mainframe databases, he said.


Standards bodies aren’t the only organizations working to ensure links between disparate databases. Several leading database vendors, looking to connect compentive databases, joined forces last year to create the New, Information Industry Cooperative Endeavor (NIICE) consortium. This group, supported by X/Open, includes database players Sybase, Computer Associates and Microsoft, as well as IBM unit Lotus Development Corp., Cambridge, Mass., and Novell Inc., Orem, Utah. Oracle was invited to join but declined, calling any potential effort put forth by NIICE “a redundancy” of X/Open’s work.

According to Paul Tanner, a business development manager at X/Open, NIICE was started to address user demands that various products work together The, problem, said Tanner, is that the release process for various database products is asynchronous. Though products are advertised as integrated, features in new releases may cause interoperability problems.

NIICE members will not be working together on APIs or other technologies. Rather, they will concentrate on establishing procedures to share technical information before new versions are released.,

The work by X/Open and NIICE is on the right track, but many companies can’t wait for standards to evolve before linking their databases. Solutions vary. Some turn to proprietary gateways from DBMS vendors. Others look to third-party gateways such as InfoHub and InfoPump from Trinzic Corp., Redwood City, Calif., Data Manager from Prism Solutions Inc., Sunnyvale, Calif., and EDA/SQL from Information Builders Inc., New York City.

Broadly, gateways take a generic SQL call from the, client to the database engine, where it’s translated. They provide RPC-like connection between applications and relational and nonrelational databases. The gateway approach, according to the Meta Group, Stamford, Conn., is adequate for simple client/server implementations.

Meta breaks the various gateway products on the market into three categories. Proprietary gateways include Oracle’s Procedural Gateway, Sybase’s Open Server and IBM’s DDCS/2. Open, or ODBC-based gateways include Sybase’s Omni Server and Enterprise Connect, IBI’s EDA/SQL, Trinzic’s InfoHub, Gupta’s DB Gateway, and Cross Access’ Cross Access Data Delivery System. Pass-through gateways include Independence Technologies’ DAL, TechGnosis’ PC-Seque Link and Intersolv’s Q+E Lib.

The solutions from the relational database vendors, said Aberdeen’s Kastner, are more sophisticated than some third-party offerings because they’re likely to be used in settings where data synchronization is mandatory. These products include Sybase’s Enterprise Connect gateway, CA’s Ingres gateways for accessing IMS and Vsam, and Oracle’s Open Gateway line, he said.

The Open Gateway family of products, said Oracle’s Simonis, includes procedural gateways that allow remote procedure calls (RPC) to be executed at a remote site, and transparent gateways for writing Oracle SQL against other databases.

Ship-to-Shore Access

The U.S. Navy is using Oracle’s Transparent Gateway to connect Sybase databases with Oracle databases, said Scott Hendrickson, senior software analyst with FGM Inc., Herndon, Va., a systems integrator that works with the Navy’s Command and Control Systems unit. The Command Center runs Oracle, while Navy ships run Sybase.

Hendrickson said they need to connect what he called “readiness” data – the status of personnel and resources, for example – stored in Oracle databases, with “intelligence” data stored in Sybase on various ships. The onshore Command Center uses an HP-UX-based server that runs Oracle 7.0.15.

To use Oracle Transparent Gateway to link the Oracle and Sybase databases, FGM engineers took Oracle’s normal database structures and put them on the Unix-based Sun box where Sybase and the gateway server reside. The purpose, said Hendrickson, was to test the gateway to see if data access to both Oracle and Sybase appeared transparent to users.

Hendrickson said Transparent Gateway’s performance is satisfactory. The middleware, he said, will ease application development burdens because ship personnel will be able to access existing applications, rather than duplicate them for ship use.

Another middleware product is IBM’s DataJoiner, which enables access to multivendor data sources, said Jeff Jones, IBM’s brand manager of data application and database systems management tools. These sources include DB2, Sybase and Oracle databases. The product can link databases running on OS/2, Windows, DOS, AIX, HP-UX and Sun Solaris.

DataJoiner joins data from disparate databases through a single SQL statement using a single interface. According to Jones, DataJoiner features include transparency, a heterogeneous join capability, and support for ODBC and CLI.

Siemens Energy and Automation, a manufacturer of electronic components in Alpharetta, Ga., turned to DataJoiner when it began its foray into client/server, said Raymond Lee, a database administrator. Siemens, primarily an MVS shop prior to its migration to client/server, chose Sybase as the database for its decision support and customer service systems. These systems require access to customer and order entry information, as well as to legacy edit tables on the IBM ES 9000 mainframe.

The firm runs Sybase on an AIX-based RS/6000 server over TCP/IP. End users have PCs and laptops.

When looking for a way to link the mainframe’s DB2 database with Sybase, Siemens evaluated DataJoiner, as well as Sybase’s own gateway products and those of Platinium Technology Inc., Oakbrook Terrace, Ill. Company officials chose DataJoiner because they liked IBM’s support and the lower projected cost, said Lee. Siemens is also implementing IBM’s DataPropagator Relational copy management tool for propagating data from DB2 to Sybase.

Despite it moves into new environments, Siemens plans to keep the mainframe and DB2 to run order entry systems. And, said Lee, they are not tied to Sybase. They are examining Oracle and other DB2 products for decision support data.

The biggest problem thus far, said Lee, involves convention disparities between Sybase and DataJoiner – Sybase uses 32-character names, while DataJoiner uses 18-character names. Siemens has resolved the issue for now by using MVS DB2 standard 18-character names. Installing the gateway was also a challenge, he said, due to client/server complexities compounded by mixed networks and operating systems.

So far, DataJoiner performance has been satisfactory, said Lee. However, Siemens is not yet in production with its new client/server systems. “When 100 users are pounding [the applications], we’ll see,” said Lee.

Rules Don’t Always Apply

For its part, Zeneca Pharmaceuticals, Wilmington, Del., uses the Ingres gateway to DB2 to connect its CA-Openlngres database with DB2 on its IBM mainframe. Zeneca uses DB2 and IMS as repositories for clinical, sales and financial data, said Mary Ann Mclntyre, a database consultant for the company.

The OpenIngres database runs on a Digital VAX, and handles transactions for various scientific and commercial systems. Zeneca installed the Ingres gateway to provide access to sales order data on DB2. With Zeneca’s previous approach to getting this data, said McIntyre, it took nearly a weck to turn reports around. The Ingres gateway has improved the turnaround to one day, she said.

On the client side, Zeneca has moved away from terminal emulation mode and has standardized on Microsoft Windows. ODBC provides end users with access to the Ingres database. Zeneca decided to go with ODBC based on Microsoft’s dominance on the desktop and its compliance with the SAG CLI.

Zeneca also uses CA-Open-Ingres/Star, a distributed database manager, and CA-OpenIngres/Net, a network gateway. Zeneca’s PCs connect through ODBC and Ingres/Net to Ingres/Star, which contains the pointers to DB2.

For application development, Zeneca uses Visual Basic, and Intersolv’s DataDirect Developer’s Toolkit and DataDirect MultiLink/VB. The DataDirect toolkit encapsulates the ODBC API. MultiLink/VB lets developers create ODBC-compliant Visual Basic applications.

Mclntyre likes the flexibility ODBC affords. “If you change data storage from DB2 to Oracle, there’s not much change to the application. You switch ODBC drivers from DB2 to Oracle and make sure your application follows the rules of Oracle, if they differ in any way from DB2.”

As for performance, Mclntyre warns that different databases behave, well, differently. Vendors, she said, have different ways of applying the relational model. “Don’t assume that if something works in Oracle, Ingres or Sybase that it’s also true for DB2 – the rules of any one database don’t apply to all,” she said.

“You pay big response time for poor application design in client/server,” Mclntyre continued. If the application does not utilize its back-end databases properly, she said, performance will suffer.

Performance isn’t the only issue users face when using middleware to get at multiple data sources. Lack of scalability and interoperability with legacy applications are oft-cited complaints as well. Still, say analysts, middleware will continue to gain importance as IS organizations demand open architectures. Many say ODBC-compliant applications will go a long way toward addressing database connectivity issues.

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