Storage parameters can be set for database tables (transparent tables, table pools, table clusters). These parameters affect the way in which tables are handled in the database. For example, the storage parameter defines the tablespace in which the table should be created in the database and the size to be selected for the table extents.
The existing storage parameters and the particular settings that are allowed depend on the database system in use. To find out which parameters can be set in your database system, please consult the system documentation for your database system.
Which Storage Parameters are Effective for a Table?
When a table is activated for the first time, the storage parameters for the table are computed from the technical settings of the table (if there are no technical settings, the default values of the database system are used) and the table is created in the database with these storage parameters.
If the table is deleted from the database and created again at a later time (for example due to a table
conversion), the storage parameters to be used are defined in a fixed hierarchy.If there are user-defined storage parameters, these are used. If there are no user-defined storage parameters, the valid parameters used previously in the database are used. If there are no such parameters either (for example if the table was previously a pooled or cluster table that was converted to a transparent table by conversion), the storage parameters are computed from the technical settings. If there are no technical settings for the table either, the default values of the database system are used.
If the technical settings of a table that already exists in the database are changed and activated, the valid storage parameters for the table in the database are not changed. In this case you have to change the valid storage parameters manually with the database utility.
Displaying and Maintaining the Storage Parameters
In the database utility, go to the table maintenance screen. You can display the storage parameters that are currently valid for the table and its indexes with Storage parameters.
The parameters displayed here depend on the database system used. You can find information about the meaning of the displayed parameters by selecting the parameter and pressing F1.
You can change some storage parameters directly. Choose . You can now enter values for the changeable parameters. Make your changes and choose Apply. The changed settings are now active in the database.
For example, if you change the extent size directly, the next table
The tablespace in which the table lies cannot be changed directly. Such a change requires that you delete the table in the old tablespace and create a new one in the new tablespace.
With Techn. setting you can display which storage parameters would be computed from the current values of the technical settings.
You can also explicitly define which storage parameters should be used next time the table or an index of the table is created. For example, this can be necessary if you changed the technical settings of the table and want to make sure that these changed settings are used when the table is
converted.Proceed as follows:
If you create the table again in the database (e.g. during a conversion), the parameters you entered will be used.
See also:
Technical Settings Oracle Database Storage Parameters in the ABAP Dictionary Informix Database Storage Parameters in the ABAP Dictionary