doc.Index.index.uda.jdbc.st

The Single-Tier JDBC Drivers are a single component installed on a data-consuming machine - depending on the architecture in which the driver is deployed, either a client such as a desktop, a workstation or an application-server machine. No components need be installed on the database server.

The OpenLink? Single-Tier suite, being installed only on client machines, is ideal for a variety of situations: if you only have one or a small number of machines on which you want to access data (e.g. you''re a home user, or deploying in application-server architecture), then you don''t need to install anything on the server machine, just the client. To the developer writing an application, there is no requirement to know on which server it resides: you can write your application for any environment, regardless of where it will end.

There are also performance benefits gained by employing this single solution, which in some cases exceeds that provided by the native drivers. Being able to integrate your solution simply into your organization with its plethora of internal and disparate systems means your RoI? increases significantly.

These drivers are built by implementing the JDBC data-access interface specifications using a database-vendor-provided Call Level Interface (CLI). Thus, the capabilities and architecture of the CLI significantly affect the functional outcome of a driver.

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JDBC, and any other data-access drivers for that matter, are developed using the call-level interface (CLI) of the respective databases that they support. These call level interfaces take the following forms:

• Type A - C-based dynamic SQL interface that inextricably includes client and server networking components
  
• Type B - C-based remote procedure calls (RPC) interface to the wire-protocol of the underlying database. This is a client-only interface that communicates directly with the remote database server. These interfaces aren’t typically available to third-party developers. To date the Open Source projects such as FreeTDS? , MySQL? , PostgreSQL? , and Interbase are the only publicly accessible and freely available versions of such interfaces.
  
• Type C - Generic bridges: these are JDBC drivers that act as implementation proxies, such that bridging can be achieved in the manner depicted in the matrix below:
  OpenLink? provides Single-Tier Drivers built using the Type A, B, and C call-level interfaces formats, depending on what is publicly available to third-party developers by the vendors of the respective database engines.

Please view your respective Data Access Mechanism for more information.