About Creating an Oracle Database

After you plan your database using some of the guidelines presented in this section, you can create the database with a graphical tool or a SQL command. You typically create a database during Oracle Database software installation. However, you can also create a database after installation. Reasons to create a database after installation are as follows:

• You used Oracle Universal Installer (OUI) to install software only, and did not create a database.
• You want to create another database (and database instance) on the same host computer as an existing Oracle database. In this case, this chapter assumes that the new database uses the same Oracle home as the existing database. You can also create the database in a new Oracle home by running OUI again.
• You want to make a copy of (clone) a database.

Considerations Before Creating the Database

Database creation prepares several operating system files to work together as an Oracle Database. You only need to create a database once, regardless of how many data files it has or how many instances access it. You can create a database to erase information in an existing database and create a new database with the same name and physical structure.

Creating a Database with DBCA

Database Configuration Assistant (DBCA) is the preferred way to create a database, because it is a more automated approach, and your database is ready to use when DBCA completes. DBCA can be launched by the Oracle Universal Installer (OUI), depending upon the type of install that you select. You can also launch DBCA as a standalone tool at any time after Oracle Database installation.

You can run DBCA in interactive mode or noninteractive/silent mode. Interactive mode provides a graphical interface and guided workflow for creating and configuring a database. Noninteractive/silent mode enables you to script database creation. You can run DBCA in noninteractive/silent mode by specifying command-line arguments, a response file, or both.