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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.
Queries and the query optimizerThese topics describe query plans, explain how the database server manages query optimization, and discuss factors that you can use to influence the query plan. These topics also describe performance considerations for SPL routines, the UDR cache, and triggers.
Time costs of a queryYou can adjust a few, but not all, of the response-time effects of actions that the database server performs when processing a query.
In-place ALTER TABLE costsFor certain conditions, the database server uses an in-place alter algorithm to modify each row when you execute an ALTER TABLE statement. After the alter table operation, the database server inserts rows using the latest definition. If your query accesses rows that are not yet converted to the new table definition, you might notice a slight degradation in the performance of your individual query, because the database server reformats each row in memory before it is returned.

In-place ALTER TABLE costs

For certain conditions, the database server uses an in-place alter algorithm to modify each row when you execute an ALTER TABLE statement. After the alter table operation, the database server inserts rows using the latest definition. If your query accesses rows that are not yet converted to the new table definition, you might notice a slight degradation in the performance of your individual query, because the database server reformats each row in memory before it is returned.

For more information about the conditions and performance advantages when an in-place alter occurs, see Altering a table definition.