Database Health Check List

Daily Checks
Alert Log
Jobs ( DBMS_JOBS, Scheduler, CronJobs )
Invalid_Objects
Grid Control Alerts
AWR Report
DashBoard
Backup successful
Standby lag is ok

Weekly Check
All the above daily
Dashboards Enhancement
Bad Queries evaluated with explain plan
Daily checks are automated
Job logs are being monitored for success/failurs
Dashboard updated and email is sent and enhanced

Monthly Check
All daily/weekly checks
Password file up to date
Any Oracle issues have updated SR

Quarterly Check
Oracle patches are reviewed
Database DB and APP diagrams are up to date