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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.
Fragmentation guidelinesOne of the most frequent causes of poor performance in relational database systems is contention for data that resides on a single I/O device. Proper fragmentation of high-use tables can significantly reduce I/O contention. These topics discuss the performance considerations that are involved when you use table fragmentation.
Improve the performance of operations that attach and detach fragmentsWhen you use ALTER FRAGMENT ATTACH and DETACH statements to add or remove a large amount of data in a very large table, you can take steps to improve the performance of the ATTACH and DETACH operations.
Improving ALTER FRAGMENT DETACH performanceYou can improve the performance of ALTER FRAGMENT DETACH statements by formulating appropriate distribution schemes for your table and index fragments and by eliminating the index build during the execution of ALTER FRAGMENT DETACH statements.

Improving ALTER FRAGMENT DETACH performance

You can improve the performance of ALTER FRAGMENT DETACH statements by formulating appropriate distribution schemes for your table and index fragments and by eliminating the index build during the execution of ALTER FRAGMENT DETACH statements.

To eliminate the index build during execution of the ALTER FRAGMENT DETACH statement, use one of the following fragmentation strategies:

Fragment the index in the same way as the table.
Fragment the index with the same distribution scheme as the table.

Important: Only logging databases can benefit from the performance improvements for the ALTER FRAGMENT DETACH statement. Without logging, the database server works with multiple copies of the same table to ensure recoverability of the data when a failure occurs. This requirement prevents reuse of the existing index fragments.