The X/Open DTP model of transaction processing differs substantially from the traditional Sybase model. The traditional Sybase TP environment is connection oriented. Programs set up connections directly between the application program and Adaptive Server using connection management SQL statements. In the XA Interface environment, the XA Interface, using LRMs, sets up connections for the application.
Table 3-1 summarizes the differences.
Traditional TP model |
X/Open DTP model |
|---|---|
There is one or more transaction per client/server connection. |
There is no notion of connections. Components communicate through interfaces. |
Transactions are usually local, with each transaction confined to a single Adaptive Server. |
Transactions are global. They span resource managers. The work done within a transaction is accomplished using more than one resource manager. |
Each Adaptive Server is responsible for the recovery of the data it contains. |
The transaction manager is responsible for recovering the data stored in all of the resource managers. |
