When the creation process is complete, connect to the database using SQL*Plus, iSQL*Plus, or Enterprise Manager to ensure proper installation of all the options and components.
Select Configure Database Options in the DBCA Operations screen .
If the database is not started, the DBCA starts it automatically. You must connect to the database as a user with DBA authority.
Now, you can add options that were not included earlier.
In the Operations screen, choose Delete A Database and click Next to open the Database screen. The DBCA lists all the databases available for deletion. If you click Finish, the DBCA removes all files on the disk associated with this database you have chosen. If you are using Windows, the DBCA also removes the service associated with the database.
Connect to SQL*Plus as an administrator with either SYSOPER or SYSDBA privileges.
/u01/app/oracle>sqlplus sys/oracle as sysdba
Once connected, you need to put the database in MOUNT mode.
Issue the following command if the database is not running:
Next, issue the following command:
This command deletes all the files associated with the database. If you are using raw disk devices, the special files created for these devices are not deleted.
DBCA can store and use XML-based templates to create your Oracle database. Saving a definition of your database in a template format makes it easier to perform various tasks.
For example, you can copy a preexisting template to modify new database definitions. The template definition is normally stored in the $ORACLE_HOME/assistants/dbca/templates directory on Unix and in the %ORACLE_HOME%\assistants\dbca\templates directory on Windows systems.
The DBCA can use two types of templates: seed and nonseed.
Seed templates are template definitions that contain database definition information and the actual datafiles and redo log files. The advantage of a seed template is that the DBCA makes a copy of the datafiles and redo logs included in the definition file. These prebuilt datafiles include all schema information, which makes for a faster database creation process. The seed templates carry a .dbc extension. The associated predefined redo logs and datafiles are stored as files having a .djf extension. When you use a seed template, you can change the database name, the datafile locations, the number of control files and redo log groups, and the initialization parameters.
Nonseed templates contain custom-defined database definitions. Unlike seed templates, they do not come with preconfigured datafiles and redo logs. Nonseed templates carry a .dbt extension.
When you connect to the DBCA, select Manage Templates in the Operations screen and click Next to open the Template Management screen.
Three template creation options are available
|From An Existing Template||Creates a new template definition from a preexisting template. This allows you to modify a variety of template settings, including parameters and datafile storage characteristics.|
|From An Existing Database (Structure Only)||Creates a new template based on the structural Characteristics of an existing database. The datafiles are created from scratch and will not include data from the original database. Choose this option when you want a database that is structurally like another database but does not contain any data. The database that you are copying from can reside anywhere in your network.|
|From An Existing Database (Structure As Well As Data)||Creates a new template based on the structural characteristics of an existing database. The datafiles and all corresponding user data are included in the new database. Choose this option when you want an exact copy of an existing database. The database you are copying must reside on the same physical server as the new database you are creating.|
The parameter file can be either a plain text file (PFILE) or a binary parameter file (SPFILE).
Default location where Oracle searches to find the PFILE and SPFILE parameter files is $ORACLE_HOME/dbs on Unix systems and %ORACLE_HOME%/database on Windows systems. Oracle uses a specific file location hierarchy to locate first SPFILE, then PFILE.
A different parameter file location can be specified and Oracle searches for this file when the above locations fail to start the database.
Changes to Initialization Parameter file can be made either manually or using EM Database Control.
Using EM: navigate to the Administration menu. In the Instance section, modifications to initialization parameters can be made.
The Initialization Parameters screen in EM Database Control has two tabs: Current and SPFile. The Current tab displays all the currently active settings for initialization parameters for the database instance.
Parameters marked Dynamic can be modified and this modification immediately affects the currently running instance without stopping the database. The changes you make from the Current tab are not permanent, so the next time the database is stopped and restarted, the settings will assume their original values.
If SPFILE is used, SPFile tab is visible. The changes made using SPFile tab are persistent across database startups and shutdowns because the changes are saved to the SPFILE definition.
Changes can be applied to SPFILE or to both SPFILE as well as currently running instance. Based on the selected option, a set of forms are presented: If template from an existing database is selected, you need to connect to the database so that the DBCA can obtain information about the database. Connect to the database as a user with DBA credentials to perform this task.
If From an existing template is selected, the template can be configured the template by following a series of screens that are similar to those used to create a database.
These screens allow you to configure the various aspects of the template, including initialization parameters and datafile and redo log locations.
Deleting Template Definitions :
In the Operations screen , click Manage Templates.
Template Management screen is presented. Select the option Delete A Database Template. Then choose the template to delete. When you remove the template, the DBCA removes the XML file from the system.