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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 ATTACH performanceYou can take advantage of the performance optimizations for the ALTER FRAGMENT ATTACH statement if your database meets certain requirements.

Improving ALTER FRAGMENT ATTACH performance

You can take advantage of the performance optimizations for the ALTER FRAGMENT ATTACH statement if your database meets certain requirements.

To take advantage of the performance optimization, you must meet all of the following requirements:

Formulate appropriate distribution schemes for your table and index fragments.
Ensure that no data movement occurs between the resultant partitions due to fragment expressions.
Update statistics for all the participating tables.
Make the indexes on the attached tables unique if the index on the surviving table is unique.

Important: Only logging databases can benefit from the performance improvements for the ALTER FRAGMENT ATTACH 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.