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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 for smart large objectsSmart large objects have several unique locking behaviors because their columns are typically much larger than other columns in a table.

Locks for smart large objects

Smart large objects have several unique locking behaviors because their columns are typically much larger than other columns in a table.

This section discusses the following unique behaviors:

Types of locks on smart large objects
Byte-range locking
Lock promotion
Dirty Read isolation level with smart large objects

Types of locks on smart large objects

The database server uses one of the following granularity levels for locking smart large objects:

The sbspace chunk header partition
The smart large object
A byte range of the smart large object

The default locking granularity is at the level of the smart large object. In other words, when you update a smart large object, by default the database server locks the smart large object that is being updated.

Locks on the sbspace chunk header partition only occur when the database server promotes locks on smart large objects. For more information, see Lock promotion.