Managing program variable space
For each client connection to a server, PowerBuilder maintains
a separate client session. Each client session
on the server has its own program variable space.
Scope rules
The scope rules for variable
and object data in a distributed application are essentially the
same as in a nondistributed application. Therefore, a global variable
initialized in a client session will retain its value on subsequent
calls to the server, and instance data for objects persist until
the instance data is destroyed.
Shared objects
To share data
between client applications, you can include some code in the server
application to enable one or more user objects to be shared. By
using shared objects, you can:
- Provide convenient
access to common data that would otherwise need to be retrieved
separately by each client connection - Reduce the number of database accesses, allowing
the database server to be available for other processing - Maintain state information in Internet applications
that use Web.PB
For more information about sharing objects
in a server application, see Chapter 27, “Building a Distributed PowerBuilder
Server”.
Other ways to share data
You can also use the following facilities to share data:
- A persistent storage
facility, such as a database or file system - Object Linking and Embedding (OLE)