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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 GuideThese topics describe how to define new data types and enable user-defined routines (UDRs) to extend HCL OneDB™.The 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™.
Improve UDR performance
Extend UPDATE STATISTICS

Extend UPDATE STATISTICS

The UPDATE STATISTICS statement collects statistics about the data in your database. The optimizer uses these statistics to determine the best path for an SQL statement.

For SQL statements that use UDTs, the optimizer can call custom selectivity and cost functions. (For more information about creating selectivity and cost functions, refer to Optimize functions in SQL statements.) Selectivity and cost functions might need to use statistics about the nature of the data in a column. When you create the statcollect() function that collects statistics for a UDT, the database server executes this function automatically when a user runs the UPDATE STATISTICS statement with the MEDIUM or HIGH keyword.