1. Oracle 9i Lite
Storing the data on the device one of task of middleware component.
For this we going for database component like oracle 9i lite and DB2e

2. What is oracle 9i lite?
Oracle 9i Lite is actually a complete solution for mobile or wireless applications that require the use of a relational database on the mobile client.
It supports Win32, Windows CE, PalmOS, and EPOC database clients, integration with Oracle's Advanced Queuing (AQ) mechanism, data and application synchronization software enterprise.

3. Some features
Oracle's Lite database product includes Oracle Mobile Agents wireless middleware and iConnect synchronization components.
Replacing the confusing amalgam
of servers like Web-To-Go Server, Consolidator Server, Synchronization Server, and so on
All replaced by a common Oracle9i Mobile Server product

4. Oracle9i Lite Relational Database
The Oracle9i Lite relational database supports 100% Java development JDBC
drivers and the database's native support for embedded SQLJ and Java stored procedures
Through ODBC Programming from any development tool like Visual Basic, C++, Delphi are supported

5. Contd…
For Oracle9i Server's object database capabilities, Oracle has included OKAPI (Object Kernel API), callable from any C/C++ application.
Oracle9i Lite also includes an interactive tool named Mobile SQL that is the mobile equivalent of Oracle's venerable SQL*Plus tool.
Mobile SQL accesses both ODBC and OKAPI interfaces, supporting both relational and object query functionality.

6. SQLJ support Java stored procedure or trigger are created using the
CREATE FUNCTION or CREATE PROCEDURE SQL command in Java classes.
The Oracle9i Lite JDBC driver fully supports the JDBC specification and provides additional support for some JDBC 2.0 features, including support for BLOB/CLOB datatypes.
Oracle9i Lite's SQLJ support enables static SQLstatements to be embedded in Java code.

7. Database synchronization
Database synchronization is accomplished through the Mobile Server and Message Generator and Processor (MGP) server- side tools included with Oracle9i Lite.
Mobile Server makes use of a "publish/subscribe" model in which one or more database "publications" can be defined, consisting of a query used to extract data from the database server.
Client-side subscriptions register with the Mobile Server and specify which publications they would like to be synchronized down to the client

8. Contd… Application logic can be built into the sync process through
the binding of PL/SQL stored procedures to publication items.
This entire publish/subscribe framework is managed through the middle-tier Mobile Server product.
Mobile Server can be accessed from a mobile client through the use of the included Java ResourceManager class.
A C-language MobileSync API is provided to support direct client-to-database-server synchronization connections.

9. Administration/Development Tools
The Mobile Server product manages the synchronizationof data to and from the mobile device.
It can also be used to manage the deployment of applications to mobile devices so that the Mobile Server allows a mobile application to be "packaged“ and hosted within the Mobile Server.
This packaging process allows applications and snapshots wrapped together into a single unit so that eachtime client will receive an up-to-date copy of application and that application's data.

10. Why it is used in pc?
Lite feature of Oracle 9i Lite reduces the size of byte code
Then it supports JDBC ,ODBC drivers and OKAPI for mobile applications.
Synchronization of data for mobile device is managed by mobile server product