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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.
Uses for a B-tree indexA B-tree index is good for a query that retrieves a range of data values. If the data to be indexed has a logical sequence to which the concepts of less than, greater than, and equal apply, the generic B-tree index is a useful way to index your data.

Uses for a B-tree index

A B-tree index is good for a query that retrieves a range of data values. If the data to be indexed has a logical sequence to which the concepts of less than, greater than, and equal apply, the generic B-tree index is a useful way to index your data.

Initially, the generic B-tree index supports the relational operators (<,<=,=,>=,>) on all built-in data types and orders the data in lexicographical sequence.

The optimizer considers whether to use the B-tree index to execute a query if you define a generic B-tree index on:

Columns used to join two tables
Columns that are filters for a query
Columns in an ORDER BY or GROUP BY clause
Results of functions that are filters for a query