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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 casts
Create a user-defined cast

Create a user-defined cast

You create a user-defined cast with the CREATE CAST statement, which registers the cast in the syscasts system catalog table. The person who registers a cast with CREATE CAST owns the cast.

For information about the syntax of the CREATE CAST statement, refer to the HCL OneDB™ Guide to SQL: Syntax. For a general discussion of using casts, refer to the HCL OneDB Database Design and Implementation Guide.

The CREATE CAST statement provides the following information about the cast to the database server:

The kind of user-defined cast to create
The cast mechanism that the database server is to use to perform the data conversion
The direction of the cast
The CREATE CAST statement specifies the source and target data types to determine the direction of the cast. For full data conversion between two data types, you must define one cast in each direction of the conversion.