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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™.
Extend an operator class
Operator classes
Secondary-access methods
Generic B-tree index

Generic B-tree index

In traditional relational database systems, the B-tree access method handles only built-in data types and therefore can compare only two keys of built-in data types. The B-tree index is useful for a query that retrieves a range of data values. To support UDTs, the database server provides an extended version of a B-tree, the generic B-tree index.

The database server uses the generic B-tree index as the built-in secondary-access method. This secondary-access method is registered in the sysams system catalog table with the name btree. When you use the CREATE INDEX statement (without the USING clause) to create an index, the database server creates a generic B-tree index. The following statement creates a B-tree index on the zipcode column of the customer table:

CREATE INDEX zip_ix ON customer (zipcode)

For more information, see the CREATE INDEX statement in the HCL OneDB™ Guide to SQL: Syntax.