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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.
Create DataBlade® objects by using BladeSmithUse BladeSmith to create DataBlade® modules.
Create DataBlade® module objectsBladeSmith uses wizards to create and edit objects.
Create data typesYou can create extended data types in BladeSmith. In addition, you must define qualified built-in data types before you can use them in a BladeSmith project.
Opaque data typeAn opaque data type is a C structure or C++/ActiveX class. The database server does not interpret the contents of the structure. Instead, it calls support routines that you provide to manipulate the structure.
Maximum sizeIf you create a variable-length opaque data type, specify the maximum allocated length of that data type. The database server does not allow an opaque data type to grow beyond its maximum length.

Maximum size

If you create a variable-length opaque data type, specify the maximum allocated length of that data type. The database server does not allow an opaque data type to grow beyond its maximum length.

If you choose to specify a maximum length, the maximum value is 32,767 bytes. This value, however, is the maximum size of a row in a database table. Therefore, if your opaque data type is 32,767 bytes, you cannot have any other columns in your table.