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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.
Creating and dropping an index in an online environmentYou can use the CREATE INDEX ONLINE and DROP INDEX ONLINE statements to create and drop an index in an online environment, when the database and its associated tables are continuously available.
Creating attached indexes in an online environmentYou can create attached indexes using the CREATE INDEX ONLINE statement, but the statement only operates when Dirty Read is the transaction isolation level.

Creating attached indexes in an online environment

You can create attached indexes using the CREATE INDEX ONLINE statement, but the statement only operates when Dirty Read is the transaction isolation level.

The index creation takes an exclusive lock on the table and waits for all other concurrent processes scanning the table to quit using the index partitions before creating the attached index. If the table is being read or updated, the CREATE INDEX ONLINE statement waits for the exclusive lock for the duration of the lock mode setting.