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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.

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.

Tip: For more information about the structure of a B-tree index and how to estimate the size of a B-tree index, see Estimating index pages.

HCL OneDB uses the generic B-tree as the built-in secondary-access method. This built-in secondary-access method is registered in the sysams system catalog table with the name btree. When you use the CREATE INDEX statement (without the USING clause) to create an index, the database server creates a generic B-tree index. For more information, see the CREATE INDEX statement in the HCL OneDB Guide to SQL: Syntax.

Tip: HCL OneDB also defines another secondary-access method, the R-tree index. For more information about how to use an R-tree index, see the R-Tree Index User's Guide.