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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.
DataBlade® Developers KitThe DataBlade® Developers Kit (DBDK) guides contain information about the tools you can use to develop and package DataBlade® modules, which extend the functionality of HCL OneDB™ databases.
DataBlade® Developers Kit User's GuideThe HCL OneDB™ DataBlade® Developers Kit Users Guide describes how to use OneDB® DataBlade® Developers Kit (DBDK) tools to develop and package DataBlade® modules.
Debugging and testing DataBlade® modules on UNIX™This section describes how to debug and perform functional tests for DataBlade® modules written in C for HCL OneDB™ on UNIX™.
The shared object fileA DataBlade® module exists in the HCL OneDB™ database server as a shared object. The shared object file is loaded into the database server the first time one of its routines is executed after the database server is started. The shared object file is unloaded every time the database server is stopped.
Symbols in shared object filesUndefined symbols in a shared object file are resolved in the database server when the file is loaded. If a symbol is missing, the load fails on the first execution of the user-defined routine, and a message is written in the server log file.

Symbols in shared object files

Undefined symbols in a shared object file are resolved in the database server when the file is loaded. If a symbol is missing, the load fails on the first execution of the user-defined routine, and a message is written in the server log file.

You cannot resolve undefined symbols in a shared object file by using definitions in another shared object file.

A symbol defined in a shared object file on the database server behaves in one of two ways:

If the symbol referenced in the shared object file is in the same source file that references it, the debugger accesses the symbol in the shared object file.
If the shared object file includes more than one source file and there is a cross-file symbol reference, the symbol is resolved in the database server. These symbols are listed as unresolved when you link the shared object file.

Important: Although most of the unresolved symbols listed when you link the DataBlade® module shared object file are resolved when the database server loads the shared object, check for mistyped symbols; these symbols are not resolved.