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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™.
Write support functions
Perform bulk copies
Import and export support functions
Export support function

Export support function

The export function takes as an argument the internal structure for the opaque type and a structure that holds the bulk-copy format of the external representation of the opaque type.

If you do not provide an export support function, the database server uses the output support function to export text data.

For C language support, the following function signature is for an export support function of an opaque data type whose internal structure is ll_longlong_t:

mi_impexp * ll_longlong_export(ll_long_t *intrnl_bcopy_format);

The ll_longlong_export() function is a cast function from the ll_longlong_t internal structure to the IMPEXP data type. It must be registered as an explicit cast function with the CREATE EXPLICIT CAST statement. For more information about cast functions, see Create casts for opaque data types.