TN AppSvr128 Maintenance of the A2ALMDB Events Table
This tech note from InSource provides instruction on the maintenance of the alarm database events table.
- Author: Rich Brooks
- Published: 05/18/2015
- Applies to: System Platform release 2014R2 and higher
Application Server includes a built in alarm database named A2ALMDB. It is created as part of the product installation. Alarm database logging is setup by default to log alarms and events to this database. The InTouch Alarm Provider needs to be enabled in the Platform, and the Storage to Historian needs to be enabled in the Application Engine for the logging to be initialized.
Click on Galaxy from the ArchestrA IDE menu to select Configure - Alarms and Events Configuration. The overall galaxy level settings for event logging are configured here.
The System, Application, and User events are historized by default. You may turn this logging off by unchecking the corresponding checkbox if required.
Wonderware does have an Alarm DB Purge/Archive utility accessed from the Start Button - Program Files - Wonderware - InTouch folder. It is recommended to run this utility on a regular basis to keep the A2ALMDB database to a manageable size.
The Purge/Archive Utility may fail to run if the events table grows too large. It is sometime necessary to truncate the data in the events table to clean up thousands or millions of unneeded events. Run the following SQL statement from SQL Server Management Studio to see how many events are currently in the table.
SELECT count(*) FROM Events
Then run the following SQL statement to permanently delete all events from the table.
TRUNCATE TABLE Events
Run the select statement again to verify the events table is emply.