Extended data types

The extensible data type system allows you to:
  • Define new data types, called extended data types, to extend the data type system
  • Define the behavior of extended data types:
    • The operations that are supported on the extended data types
    • New operator class that supports the extended data type and provides new functionality for a secondary-access method
    • Additional casts to provide data conversions between the extended data types and other data types
    • Functions that collect statistics for the optimizer
You can define the following extended data types:
  • Complex data types
    • Collection types
    • Row types
  • UDTs
    • Opaque data types
    • Distinct data types

The database server stores information about extended data types in the sysxtdtypes and sysxtdtypeauth system catalog tables. For information about these tables, refer to the HCL OneDB™ Guide to SQL: Reference.