Glossary

aging

Delete cache instances from the cache tables of a cache group after a specified period of time (time-based) or when a specified level of database usage is reached (LRU).

asynchronous writethrough (AWT) cache group

A cache group in which committed updates on TimesTen cache tables are automatically and asynchronously propagated to the cached Oracle tables. The commit on the TimesTen database occurs asynchronously from the commit on the Oracle database.

automatic refresh

Committed updates on cached Oracle tables are automatically refreshed to the TimesTen cache tables.

autorefresh cache group

A read-only cache group or a user managed cache group that uses the AUTOREFRESH MODE INCREMENTAL cache group attribute.

bidirectional transmit

Propagate committed updates on TimesTen cache tables to the cached Oracle tables, and refresh committed updates on cached Oracle tables to the TimesTen cache tables.

cache administration user

Oracle user that creates and maintains Oracle objects that store information used to manage cache grids and enforce predefined behaviors of particular cache group types.

cache agent

A TimesTen process that processes cache group operations, such as automatic refresh, loading a cache group, and passing through statements to the Oracle database for execution.

cache group

Defines the data from the Oracle tables to cache in a TimesTen database. A cache group can cache all or a subset of a single Oracle table or a set of related Oracle tables. If multiple Oracle tables are cached, each cache table (except for the root table) must reference another cache table in the cache group through foreign key constraints.

cache grid

A set of distributed grid members consisting of TimesTen in-memory databases that work together to cache data from a single Oracle database and guarantee cache coherence among the TimesTen databases.

cache group primary key

The primary key of the cache group's root table.

cache instance

A specific row of data identified by the primary key in the cache group's root table. If there are multiple tables in the cache group, the cache instance consists of the set of rows in the child tables associated by foreign key relationships with the row in the root table.

cache manager user

TimesTen user that performs cache grid and cache group operations such as creating and configuring a cache grid, and creating cache groups.

cache table

The root table or a child table in a cache group.

cache table users

TimesTen users who own cache tables.

child table

A cache table that has a foreign key reference to either the primary key of the root table or another child table that either directly or indirectly references the root table. The table hierarchy in your cache group can designate child tables to be parents of other child tables. No cache table can be a child to more than one parent in the cache group.

dynamic cache group

A cache group category for which data in its cache tables can be loaded on demand, manually loaded or automatically loaded.

dynamic load

The transfer of data into the local grid member from Oracle tables when a query cannot be satisfied with data in the cache grid members.

explicitly loaded cache group

A cache group category for which data in its cache tables are manually or automatically loaded.

flush

To manually propagate committed inserts or updates on TimesTen cache tables in a user managed cache group to the cached Oracle tables.

global cache group

A cache group classification where data in its cache tables are shared across multiple TimesTen databases within a cache grid.

grid data transfer

Transfer of the cache instance from remote grid members to the local grid member in response to a query that cannot be satisfied by data in the cache tables on the local grid member.

grid member

A component of a cache grid consisting of either a standalone TimesTen database or an active standby pair.

grid node

A TimesTen database of a grid member that is either a standalone database, or the active database or standby database of an active standby pair.

load

Copy new cache instances from the cached Oracle tables to the TimesTen cache tables. Cache instances that are already exist in the cache tables are not updated or deleted.

local cache group

A cache group classification where data in its cache tables are not shared across multiple TimesTen databases even if the databases are members of the same cache grid.

Oracle schema users

Oracle users who own Oracle tables to be cached in a TimesTen database.

Oracle timesten user

Oracle user who owns Oracle tables that store information about cache grids.

propagate

Transmit committed updates on TimesTen cache tables to the cached Oracle tables.

read-only cache group

A cache group in which committed updates on cached Oracle tables are automatically refreshed to the TimesTen cache tables. You cannot update cache tables directly in a read-only cache group.

refresh

For an explicitly loaded cache group, unload and then load the cache group.

For a dynamic cache group, replace existing cache instances in the cache tables with the most current data from the cached Oracle tables.

replication

The process of maintaining duplicate copies of data in multiple databases.

replication agent

Replication at each master and subscriber TimesTen database is controlled by a replication agent process. The replication agent on the master database reads the transaction log records and transmits any committed updates on replicated elements to the replication agent on the subscriber database. The replication agent on the subscriber database then applies the updates to its database.

For an AWT cache group, the replication agent transmits committed updates on its cache tables to the cached Oracle tables.

root table

The parent table in the cache group that does not reference any other table in the cache group through a foreign key constraint. The primary key of the root table is the primary key of the cache group.

synchronous writethrough (SWT) cache group

A cache group in which committed updates on TimesTen cache tables are automatically and synchronously propagated to the cached Oracle tables. When an application commits a transaction, it is committed on Oracle before it is committed on TimesTen.

system managed cache group

System managed cache groups enforce predefined behaviors. The types of system managed cache groups are read-only, synchronous writethrough and asynchronous writethrough.

TT_CACHE_ADMIN_ROLE role

Role granted to the cache administration user that defines privileges on the Oracle tables owned by the timesten user which store information about cache grids.

user managed cache group

A cache group that implements customized behavior such as bidirectional transmit.

unload

Delete cache instances from a cache table. The rows in the cached Oracle tables are not affected.