Database Maintenance

Oracle 10g provides many tools for proactively identifying and fixing potential performance and management problems in the database. At the core of the monitoring system is the Automatic Workload Repository (AWR), which uses the MMON background process to gather statistics from the SGA and store them in a collection of tables owned by the user SYSMAN.Following each AWR statistics collection interval, the Automatic Database Diagnostic Monitoring (ADDM) feature examines the newly gathered statistics and compares them with the two previous AWR statistics to establish baselines in an attempt to identify poorly performing components of the database. The ADDM then summarizes these findings on the EM Database Control main and Performance screens. Using these screens, you can identify and examine the SQL statements that are contributing the most to DB Time. You can further explore the opportunities for improving the performance or manageability of your database using the EM Database Control advisors, which include the SQL Tuning Advisor, SQL Access Advisor, Memory Advisor, Mean Time To Recover Advisor, Segment Advisor, and Undo Management Advisor.