4. Importent views - sayanbhattacharya1234/Oracle_DBA GitHub Wiki
Views in database
1. Info about all tables in the DB.
2. Column details for all tables.
3. Index details.
4. Space usage by segments (very important).
5. Extent-level storage details.
6. All datafiles in the database.
7. Temporary datafiles.
8. Free space in tablespaces.
9. All tablespaces in DB.
10. Instance details.
11. Database details (name, mode, etc.).
12. Active sessions (top view for monitoring).
13. Background/user process info.
14. SQL statements in shared pool.
15. Wait events.
16. Locking info.
17. Temp tablespace usage.
18. Memory usage (SGA/PGA).
19. OS-related stats.
20. All users with details.
21. List of roles.
22. System privileges.
23. Object & column privileges.
24. Which roles are granted to users.
25. Profile definitions.
26. Tablespace quotas for users.
27. Archive log details.
28. Redo logfile info.
29. Log switch history.
30. RMAN backup sets.
31. Datafile status (very useful).
32. Files needing recovery.
33. FRA usage.
34. RMAN command history.
35. Disk group info.
36. Disk-level info.
37. ASM-managed files.
38. DB instances connected to ASM.
39. Queryable alert log.
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40. Critical alerts.
41. Audit records.
42. Resource usage limits.
43. Undo usage.
44. AWR historical views.
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