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Extending HCL OneDB™Beyond standard relational database objects, HCL OneDB™ can be extended to handle specialized data types, access methods, routines, and other objects. HCL OneDB™ includes many built-in extensions that are fully integrated in the database server. HCL OneDB™ also provides DataBlade® modules, which are packages of extended database objects for a particular purpose and that are installed separately from the database server. Alternatively, you can create your own user-defined objects for HCL OneDB™.
Creating extensionsYou can create user-defined data types, routines, access methods, and other database objects to suit your needs. You can use application programming interfaces to write user-defined routines and applications that access data in HCL OneDB™ databases.
User-Defined Routines and Data Types Developer's GuideThe HCL OneDB™ User-Defined Routines and Data Types Developer's Guide describes how to define new data types and enable user-defined routines (UDRs) to extend HCL OneDB™.
Create user-defined aggregates
Manage aggregates
Parallel execution of aggregates

Parallel execution of aggregates

In aggregate-only queries, the database server can break the computation of the aggregate into several pieces and compute each piece in parallel. The database server then uses the COMBINE function to combine the partial results from all pieces in a single result value. The database server uses the optimizer to decide when and how to parallelize an aggregate. This action is transparent to the user.

In queries that are not exclusively aggregate, the database server can still compute multiple aggregate results in parallel. In such cases, the database server computes each aggregate result sequentially (without using the COMBINE function).

For more information about parallelization and optimization, refer to the HCL OneDB™ Performance Guide.