Scopes when running with spfile

oracle> export ORACLE_SID=ssss

oracle> sqlplus / as sysdba

SQL> startup

SQL> select name,open_mode,log_mode from V$database;

SQL> select instance_name,status from V$instance;

SQL> show parameter undo_

SQL> desc V$parameter

SQL> select name,value,issys_modifiable from V$parameter where name='undo_retention';

                If the issys_mod is true/immediate then its "dynamic parameter".

                If issys_mod is false, it means that its a static parameter.

SQL> show parameter spfile

SQL> show parameter pfile

SQL> alter system set undo_retention=1000 scope=both;

                If we wont specify the scope for dynamic parameter when running with spfile, it take "both" by default.

                "both" means it is applicable for current and future instance.

SQL> show parameter undo_

SQL> show parameter memory_

SQL> select name,value,issys_modifiable from V$parameter where name="memory_max_target";

                If issys_mod is false, it means that its a static parameter.

SQL> alter system set memory_max_target=900m scope=spfile;

SQL> show parameter memory_

SQL> shut immediate

SQL> startup

                We need to shut and start the database to see the effect of changed static parameter if the database is running with spfile.

SQL> show parameter memory_