In the QDB, current data point information is stored in the DataHeader and Data_yyyymmdd tables. These two tables provide the information for real-time charts and graphs.
The DataHeader table stores identifying information about the data stream, such as the job ID, computer name, script name, maximum days, current points, and the data legend. Each data stream has a unique identifier, or primary key, which enables the Data_yyyymmdd tables to reference the information.
The Data_yyyymmdd tables store individual data point values, the time each data point was collected, and short and long detail messages associated with data points (if you set jobs to collect data detail).
The amount of data AppManager collects at each interval can quickly grow unmanageable and affect database and console performance. By default, the NetIQ Remove Old Data QDB job runs every day at 2:30 a.m. to remove Data_yyyymmdd tables that are older than the number of days you specify for Remove old data after in the Control Center console options and updates the consoles to reflect removal of the old data. The default data retention period is 30 days. If you specify zero days, the job does not remove any data. For information about setting the console options, see the Control Center User Guide for AppManager, available on the AppManager Documentation page.
If you set the Control Center console options so that the NetIQ Remove Old Data QDB job does not remove data, you should periodically remove information that you no longer need. The database size should not expand indefinitely, or database corruption could occur, making your environment unstable or unusable. Establish a regular backup strategy for saving historical information, or follow a policy of manually removing data after a certain period of time.
NOTE:If a data stream is deleted from the Graph Data tab in the Operator Console, the record is deleted from the DataHeader table. You can set the Remove associated data when jobs are deleted repository preference to delete data from both the Data_yyyymmdd and DataHeader tables when jobs are deleted, no matter how long the information has remained in the tables. For more information about deleting data, see the chapter Managing Data.