Which default-values for Oracle-settings are necessary when using RDB-archiving?
When an Oracle installation is made the parameters are set to the default-settings.
Some of these parameters have to be modified when using RDB-archiving for WinCC OA.
-- parameters initial_size and next_size
The inital_size defines the size for a tablespace when it is created. If the predefined tablespace is not sufficient the tablespace will be extend with the size defined in the parameter next_size.
The minimum-value for an archive-set in WinCC OA is 500MB and can be modified to the requirements of your project.
When the size for the archive-set is defined you have to set the initial_size to the same value, at least to value of 500MB. We suggest to set the next_size-parameter to 64MB.
The settings have to be made in the RDB_config.sql-file:
define initial_size = '500M'
define next_size = '64M'
The default-values are
define initial_size = 12M
define next_size = 10M
-- number of "online" tablespaces
The default value for the number of "online" tablespaces is 200. This values has to be modified according to the settings in your project. The required value can be calculated with the following rule. The archive groups are defined at RDB-settings:
number of "online" tablespaces for archive group 1 +
number of "online" tablespaces for archive group 2 +
number of "online" tablespaces for archive group 3 +
....
number of "online" tablespaces for archive group n +
reserve
= total number of "online" tablespaces
The current setting for the number of "online" tablespaces can be read with the following command:
select value from v$parameter where name = 'db_files';
To modify the parameter you have to call the command:
alter system set db_files=<total number of "online" tablespaces> scope=spfile;
E.g.: modify the parameter to 1000 "online" tablespaces
alter system set db_files=1000 scope=spfile;
When the settings have been modified you have to restart the Oracle database to apply the settings.