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AdministeringIn addition to administering the database server, you can tune performance, replicate data, and archive data.
System administrationThese topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL OneDB™ database servers.
Performance GuideThe HCL OneDB™ Performance Guide describes how to configure and operate your HCL OneDB™ database server to improve overall system throughput and to improve the performance of SQL queries.
Indexes and index performance considerationsHCL OneDB™ provides several types of indexes. Some performance issues are associated with indexes.
Indexes on user-defined data typesYou can define your own data types and the functions that operate on these data types. You can define indexes on some kinds of user-defined data types.
Defining indexes for user-defined data typesAs with built-in data types, you might improve the response time for a query when you define indexes for new data types.
B-tree secondary-access method HCL OneDB™ provides the generic B-tree index for columns in database tables. In traditional relational database systems, the B-tree access method handles only built-in data types and therefore it can only compare two keys of built-in data types. The generic B-tree index is an extended version of a B-tree that HCL OneDB™ provides to support user-defined data types.
Extending a generic B-tree indexInitially, the generic B-tree can index data that is one of the built-in data types, and it orders the data in lexicographical sequence. However, you can extend a generic B-tree for some other data types.

Extending a generic B-tree index

Initially, the generic B-tree can index data that is one of the built-in data types, and it orders the data in lexicographical sequence. However, you can extend a generic B-tree for some other data types.

You can extend a generic B-tree to support columns and functions on the following data types:

User-defined data types (opaque and distinct data types) that you want the B-tree index to support
In this case, you must extend the default operator class of the generic B-tree index.
Built-in data types that you want to order in a different sequence from the lexicographical sequence that the generic B-tree index uses
In this case, you must define a different operator class from the default generic B-tree index.

An operator class is the set of functions (operators) that are associated with a nontraditional B-tree index. For more details on operator classes, see Choosing operator classes for indexes.