Keeping Oracle database in Read-Write Mode-Oracle 9i

This is useful for keeping  9i oracle DR databases in read-write mode

SQL>
SQL> alter database recover managed standby database cancel;
Database altered.
SQL> shut immediate
ORA-01109: database not open

Database dismounted.
ORACLE instance shut down.
SQL> startup nomount
ORACLE instance started.
Total System Global Area 6347169792 bytes
Fixed Size                  2240016 bytes
Variable Size            2550137328 bytes
Database Buffers         3758096384 bytes
Redo Buffers               36696064 bytes
SQL> alter database mount standby database;
Database altered.
SQL>
SQL> alter system set DB_RECOVERY_FILE_DEST_SIZE=100G scope=both;
System altered.
SQL>
SQL> alter system set DB_RECOVERY_FILE_DEST='/DR_ARCHIVE/LESB_FLASH'
SQL> scope=both;
System altered.
SQL>
SQL> alter system set db_flashback_retention_target=2880;
System altered.
SQL>
SQL> create restore point before_open_standby guarantee flashback
SQL> database;
Restore point created.
SQL>
SQL>
SQL> alter database activate standby database;
Database altered.
SQL>
SQL> shut immediate
ORA-01109: database not open

Database dismounted.
ORACLE instance shut down.
SQL>
SQL> startup
ORACLE instance started.
Total System Global Area 6347169792 bytes
Fixed Size                  2240016 bytes
Variable Size            2550137328 bytes
Database Buffers         3758096384 bytes
Redo Buffers               36696064 bytes
Database mounted.
Database opened.
SQL>
SQL> select name,open_mode from v$database;
NAME      OPEN_MODE
--------- --------------------
TEST      READ WRITE
SQL>
SQL> @test_defer.sql
Error accessing PRODUCT_USER_PROFILE
Warning:  Product user profile information not loaded!
You may need to run PUPBLD.SQL as SYSTEM Connected.
System altered.
SQL> exit