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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 an opaque data type
Creating an opaque data type
Create the internal structure in C
Data type size

Data type size

To save space in the database, lay out internal structures as compactly as possible. The database server stores values in their internal representation, so any internal structure with padding between entries consumes unnecessary space.

The INTERNALLENGTH keyword of the CREATE OPAQUE TYPE statement supplies the final size of the internal structure. This keyword provides the following two ways to specify the size:

Specify the actual size, in bytes, of the internal structure to define a fixed-length opaque data type.
Specify the VARIABLE keyword to define a varying-length opaque data type.