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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
Extending an existing operator class
Reasons for extending btree_ops

Reasons for extending btree_ops

The strategy functions of btree_ops are the relational operations that end users can use in expressions. (For a list of the relational operators, see B-tree strategy functions.) The generic B-tree index handles only the built-in data types. When you write relational-operator functions that handle a new UDT, you extend the generic B-tree so that it can handle the UDT in a column or a user-defined function. To create B-tree indexes on columns or functions of the new data type, you must write new relational-operator functions that can handle the new data type.

In the relational-operator functions, you determine the following behavior of a B-tree index:

What single value does the B-tree secondary-access method use to order the index?
For a particular UDT, the relational-operator functions must compare two values of this data type for the data type to be stored in the B-tree index.
In what order does the B-tree index sort the values?
For a particular UDT, the relational-operator functions must determine what constitutes an ordered sequence of the values.

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