ctl,
/u03/oracle/whse2/ctrlwhse3.ctl'
scope=spfile;
The other possible values for SCOPE in the alter system command are MEMORY and BOTH.
Specifying either one of these for SCOPE returns an error, because the CONTROL_FILES
parameter cannot be changed for the running instance, only for the next restart of the instance.
Therefore, only the SPFILE is changed.
In either case, the next step is to shut down the database. Copy the control file to the new
destinations, as specified in CONTROL_FILES, and restart the database. You can always verify
the names and locations of the control files by looking in one of the data dictionary views:
select value from v$spparameter where name='control_files';
This query will return one row for each multiplexed copy of the control file. In addition, the
view V$CONTROLFILE contains one row for each copy of the control file along with its status.
Redo Log Files
Redo log files are multiplexed by changing a set of redo log files into a redo log file group. In a
default Oracle installation, a set of three redo log files is created. As you learned in the previous
section on redo log files, after each log file is filled, it starts filling the next in sequence. After the
third is filled, the first one is reused. To change the set of three redo log files to a group, we can
add one or more identical files as a companion to each of the existing redo log files. After the
groups are created, the redo log entries are concurrently written to the group of redo log files.
Pages:
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108