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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.
Choosing operator classes for indexesFor most situations, use the default operators that are defined for a secondary-access method. However, when you want to order the data in a different sequence or provide index support for a user-defined data type, you must extend an operator class.
Operator classesAn operator class is a set of function names that is associated with a secondary-access method. These functions allow the secondary-access method to store and search for values of a particular data type.
Default operator classesEach secondary-access method has a default operator class associated with it. By default, the CREATE INDEX statement associates the default operator class with an index.

Default operator classes

Each secondary-access method has a default operator class associated with it. By default, the CREATE INDEX statement associates the default operator class with an index.

For example, the following CREATE INDEX statement creates a B-tree index on the postalcode column and automatically associates the default B-tree operator class with this column:

CREATE INDEX postal_ix ON customer(postalcode)

For more information about how to specify a new default operator class for an index, see User-defined operator classes.