Support for Applications

Programming environment

Applications for OLAP Services are developed in Java using the OLAP API, as explained in Chapter 2. You cannot run Windows C++, HTML, or Java applications that were developed for use with Express Server.

Programs developed in the Express SPL can be modified using the OLAP Worksheet and executed by the OLAP API. These programs may need to be revised to remove SPL commands that are no longer available.

Communications

OLAP Services uses CORBA communications for its Java applications. Communications through SNAPI and Express Web Agent are no longer available. Session sharing is not supported.

OLAP Worksheet uses XCA for communication with the analytic workspace. However, XCA is not supported for user-developed applications and may produce unexpected results.

Access to relational data

An OLAP service has a child-to-parent relationship with an Oracle relational database. An OLAP Services session is always connected to the database. You do not open a connection with the database as a separate or optional step.

You can retrieve data from the relational database in the following ways:

• The OLAP API uses the analytic workspace as a temporary or transient cache during a session. Selection and manipulation of the data is done entirely in the relational database before the data is fetched into a workspace. At the end of a session, the workspace is discarded.

• The OLAP DML's SQL command fetches data into dimensions and variables for further manipulation. At the end of a session, this persistent analytic workspace can be saved or discarded.

ODBC is not available, and thus access to third-party databases is not available through OLAP Services.

Oracle Express Relational Access Administrator and Oracle Express Relational Access Manager are not available in OLAP Services.

Express SPL

Numerous changes have been made to the Express Stored Procedure Language (now called the OLAP Data Manipulation Language). Support in the following areas has been added to the OLAP DML to provide compatibility with the RDBMS:

• Parallel aggregate

• Globalization Technology options

• Byte manipulation functions

• Data conversion functions

• New data types

Support in the following areas has been dropped:

• EXTCALL

• ODBC

• SNAPI

• XCA

• Operating system commands

For comprehensive lists of new, obsolete, and significantly revised commands, open OLAP DML Help and click List of Changes on the Contents page.

Metadata

In OLAP Services, the database administrator defines multidimensional objects and associated metadata in the relational database using the OLAP Management tool of Oracle Enterprise Manager, as described in Chapter 4.

The OLAP Worksheet allows DBAs to create objects in the analytic workspace by issuing DML commands. For the OLAP API to access these objects, the appropriate Express Common Metadata (ECM) must be defined.

Oracle Express Administrator is not available in OLAP Services, and the Oracle Express Objects metadata that it generated is not used by the OLAP API.