Configuring Cache Isolation at the Project Level

If you plan to use isolated sessions ("Cache Isolation"), you must configure descriptors as isolated for any object that you want confined to an isolated session cache.

Configuring a descriptor to be isolated means that TopLink will not store the object in the shared session cache and the object will not be shared across client sessions. This means that each client will have their own object read directly from the database. Objects in an isolated client session cache can reference objects in their parent server session's shared session cache, but no objects in the shared session cache can reference objects in an isolated client session cache. Isolation is required when using Oracle Database Virtual Private Database (VPD) support or database user-based read security. Isolation can also be used if caching is not desired across client sessions.

Table 22-12 summarizes which projects support cache isolation configuration.

Table 22-13 Project Support for Cache Isolation Configuration

Descriptor	Using TopLink Workbench	Using Java
Relational Projects
EIS Projects
XML Projects

The cache isolation options you configure at the project level apply globally to all descriptors. Use this section to define global options for a TopLink project.

You can override the project-level configuration by defining cache isolation options at the descriptor level. For information, see "Configuring Cache Isolation at the Descriptor Level".

Note: When using TopLink Workbench, changing the project's default cache isolation option does not affect descriptors that already exist in the project; only newly added descriptors ar affected.

Using TopLink Workbench

To specify the cache isolation options, use this procedure:

1. Select the project object in the Navigator.

2. Select the Defaults tab in the Editor. The Defaults tab appears.

   Figure 22-11 Defaults Tab, Isolation Options

   
   Description of "Figure 22-11 Defaults Tab, Isolation Options"
   
   

Use the Isolation list to choose one of the following:

• Isolated–if you want all objects confined to an isolated client session cache. For more information, see "Cache Isolation".

• Shared–if you want all objects visible in the shared session cache (default).