Teradata Database contains a number of log tables that accumulate data, either automatically or after certain features are enabled. Because log data grows over time, you must periodically purge older information to avoid using up permanent space.
| Logs | Description |
|---|---|
| Logs that can be purged manually or using Teradata Viewpoint. See Deleting Old Log Data with Teradata Viewpoint . | |
| Access Log (DBC.AccLogTbl) | Data collected as defined in a BEGIN LOGGING statement, for each privilege check of an attempted user access of a database object. |
DBQ Logs:
|
Data collected during database query logging (DBQL), if DBQL is enabled. |
| Event Log (DBC.EventLog) | Data collected automatically by the system for each user logon event. |
ResUsage Logs:
|
ResUsage tables collect data on system resource usage. You can enable ResUsage data collection and set the collection rate using either:
The collection rate determines how quickly data accumulates and when the logs should be purged. |
| SWEvent Log (DBC.SW_Event_Log) | The system automatically inserts rows in response to software errors and system events, for use by Teradata Customer Service. |
TDWM Logs:
|
Logs for Teradata Viewpoint workload management functions. |
| Logs that must be purged manually purged | |
| In Doubt transaction Log (DBC.InDoubtResLog) | Contains a row for each transaction where completion was in doubt. |
Depending on site requirements, you may need to retain older data long after it should be removed from an active log. If so, you can create backup log tables to store log history and periodically copy data from the active logs to the backup tables. You can also archive copies of the backup tables on tape for long-term reference.