Technical data

Incremental autorefresh becomes full autorefresh
Troubleshooting Oracle In-Memory Database Cache 4-19
■ The TimesTen data store has been destroyed without using the DROP CACHE
GROUP statement.
■ A customer application inadvertently modifies the objects directly in the Oracle
database.
■ A DDL operation occurs on the base table on the Oracle database. This disables the
trigger that controls autorefresh operations.
The cache group needs to be re-created if one of the preceding conditions has
occurred.
Incremental autorefresh becomes full autorefresh
Incremental autorefresh can become full autorefresh if the cache administration user
tablespace becomes full.
This section includes the following topics:
■ Detecting when incremental autorefresh becomes full
■ Understanding the cache administration user tablespace
■ Diagnosing a full cache administration user tablespace
■ Monitoring the usage of the cache administration user's tablespace
■ Considerations when the cache administration user's tablespace is full
Detecting when incremental autorefresh becomes full
You can detect when incremental autorefresh becomes full refresh by several methods:
■ Check for messages in the support log that indicate full autorefresh operations are
occurring. For example:
2007-08-08 08:06:51.35 Warn: ORA: 22119: ora-22119-0015-refresh05652: A full
autorefresh will be performed for Incremental autorefresh table USER1.READTAB
because change log table T_03_55555_L on Oracle has been truncated.
■ Use the ttCacheAutorefreshStatsGet procedure.
– If autorefresh is InProgress for longer than usual, full autorefresh may be
occurring.
– If a much larger number of rows (autoRefNumRows) was autorefreshed than
usual, full autorefresh may have occurred.
Check the support log for messages about full autorefresh.
■ If SNMP traps are enabled, the ttCacheRecoveryAutorefreshTrap SNMP
trap indicates a full autorefresh.
Understanding the cache administration user tablespace
TimesTen strongly recommends creating a separate tablespace for the cache
administration user. This tablespace is used as the cache administration user's default
tablespace. The tablespace contains autorefresh triggers for each Oracle table, change
log tables for each Oracle table, and other objects that TimesTen needs for each cache
administration user. If you do not specify a separate tablespace, then these objects are
placed in the Oracle system tablespace.