2. SQL> alter database open read write;
    3. alter database open read write
    4. *
    5. ERROR at line 1:
    6. ORA-16003: standby database is restricted to read-only access
    9. SQL> shutdown immediate;
    10. ORA-01109: database not open
    13. Database dismounted.
    14. ORACLE instance shut down.
    15. SQL> startup nomount;
    16. ORACLE instance started.
    18. Total System Global Area 3221222464 bytes
    19. Fixed Size            8901696 bytes
    20. Variable Size          771751936 bytes
    21. Database Buffers     2432696320 bytes
    22. Redo Buffers            7872512 bytes
    23. SQL>  alter database mount standby database;
    25. Database altered.
    27. SQL> alter database activate standby database;
    29. Database altered.
    31. SQL>  shutdown immediate;
    32. ORA-01109: database not open
    35. Database dismounted.
    36. ORACLE instance shut down.
    37. SQL> startup open;
    38. ORACLE instance started.
    40. Total System Global Area 3221222464 bytes
    41. Fixed Size            8901696 bytes
    42. Variable Size          771751936 bytes
    43. Database Buffers     2432696320 bytes
    44. Redo Buffers            7872512 bytes
    45. Database mounted.
    46. Database opened.
    47. SQL>  select open_mode from v$database;
    49. OPEN_MODE
    50. --------------------
    51. READ WRITE
    53. SQL>