Before You Begin

This 10-minute tutorial shows you how to use Enterprise Manager Express to explore the structure of your database.

Select the Oracle Database release:

Background

An Oracle database is made up of physical and logical structures. Physical structures are visible in the operating system. An example of a physical structure is an operating system file that stores data on a disk. Logical structures are defined and known to the Oracle Database server, but are not known to the operating system. An example of a logical structure is a tablespace. In this tutorial you will view logical structures in your database and understand how they relate to physical structures in the operating system.

What Do You Need?

• Oracle Database 18c19c

View Control File Information

An Oracle database is made up of physical and logical structures. Physical structures are defined in the operating system. Physical files that store data on a disk are an example of a physical structure. Logical structures are defined in the database and are not known in the operating system. To view storage structure information, perform the following steps:

1. Enter the URL for Enterprise Manager Database Express in your browser and log in as the SYSTEM user.

   

   Note:Starting with Oracle Database 19c, Oracle EM Express, the default management option for Oracle Database, is based on Java JET technology. Currently, only the Performance menu is available in the 19c JET version. Therefore, we are using the 18c Flash Oracle EM Express in our tutorials. Use the following command to revert to Flash Oracle EM Express:

   SQL> @?/rdbms/admin/execemx emx

   To return to 19c JET Oracle EM Express, use the following command:

   SQL> @?/rdbms/admin/execemx omx

2. Select Control Files in the Storage menu.

   

3. The Control Files page is displayed. The Control File Information section provides information about the creation and most recent modification to the control file. In the List of Control Files section, the control file names are provided. More than one file name indicates that the control file is multiplexed. The Control File Sections section provides information about the data that is stored in the control file.

   

4. Click ORCL to return to the Database Home page.

View Online Redo Log Information

1. Select Redo Log Groups in the Storage menu.

   

2. The Redo Log Groups page is displayed. This page lists the redo log groups that have been configured for your database. A value of Current in the Status column indicates the group that is currently being written to. If the redo log groups are multiplexed, more than one member is shown for the group.
   Note: In this tutorial, the current group is Redo Log Group 3. The current group may differ when you perform this tutorial.

   

3. Click ORCL to return to the Database Home page.

Viewing Archived Redo Log Information

1. Select Archive Logs in the Storage menu.

   

2. The Archive Logs page is displayed. If your database is not in ARCHIVELOG mode, you will not have any archived redo log files.

   

3. Click ORCL to return to the Database Home page.