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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.
LockingThe database server uses locks, which can affect concurrency and performance. You can monitor and administer locks.
Locks with the SELECT statementThe type and duration of locks that the database server places depend on the isolation level set in the application, the database mode (logging, nonlogging, or ANSI,) and on whether the SELECT statement is within an update cursor. These locks can affect overall performance because they affect concurrency.
Locking nonlogging tablesThe database server does not place page or row locks on a nonlogging table when you use the table within a transaction. However, you can lock nonlogging tables to prevent concurrency problems when other users are modifying a nonlogging table

Locking nonlogging tables

The database server does not place page or row locks on a nonlogging table when you use the table within a transaction. However, you can lock nonlogging tables to prevent concurrency problems when other users are modifying a nonlogging table

Use one of the following methods to prevent concurrency problems when other users are modifying a nonlogging table:

Lock the table in exclusive mode for the whole transaction.
Use Repeatable Read isolation level for the whole transaction.

Important: Nonlogging raw tables are intended for fast loading of data. You should change the table to STANDARD before you use it in a transaction or modify the data within it.