How to view oracle database
With the rapid development of information technology, databases have become the cornerstone of enterprise informatization, and Oracle is one of the world's largest relational database management systems. As one of the widely used databases, it is important to look at Oracle database. This article mainly introduces how to view the Oracle database.
1. Check the Oracle database version information
Oracle is a large database system, and its version information is very important. It is not only a reference for its maintenance and upgrade, but also during database upgrade and It will also be used during backup and recovery.
To view Oracle database version information, you can use the SQLPlus command line tool. Enter the following statement in the command line:
SELECT * FROM v$version;
This statement will display the version information of the Oracle database. Among them, "v$version" is one of Oracle's views, used to display the version information of each component in the database.
2. View Oracle database instance
Oracle database instance refers to the running Oracle process, including SGA, PGA and background processes. To view the database instance, you can use the SQLPlus command line tool and enter the following statement:
SELECT * FROM v$instance;
This statement will display the instance name, host name, and version of the Oracle database Information etc. Among them, "v$instance" is one of Oracle's views, used to display related information of database instances.
3. View Oracle database table space
Oracle table space is a logical structure used to store and manage data. It is a collection of one or more data files and is used to organize tables, indexes, etc. . When viewing the table space, you need to use the SQLPlus command line tool to execute the following statement:
SELECT * FROM dba_tablespaces;
This statement will display the name, size, status and other information of all table spaces in the Oracle database. Among them, "dba_tablespaces" is one of Oracle's views, which can display all table spaces in the database.
4. View Oracle database users
Oracle database users refer to people or applications that can access the database and perform related operations. To view Oracle database users, you can use the SQLPlus command line tool and execute the following statement:
SELECT * FROM dba_users;
This statement will display all user information in the Oracle database, including user ID, Roles, default table spaces, etc.
5. View Oracle database process
Oracle database process refers to the running Oracle instance process, including foreground process and background process, and provides the function of communicating with the client. To view the Oracle database process, you can use the SQLPlus command line tool and execute the following statement:
SELECT * FROM v$process;
This statement will display all process information in the Oracle database, including process ID, process type, process status, etc.
6. View Oracle database connection
Oracle database connection refers to the session established between the client and the database, which is used for database-related operations. To view the Oracle database connection, you can use the SQLPlus command line tool and execute the following statement:
SELECT * FROM v$session;
This statement will display all connection information in the Oracle database, including sessions ID, username, client name, etc.
Conclusion:
This article mainly introduces how to view the Oracle database, including version information, instances, table spaces, users, processes and connections, etc. This information is very important for the management and maintenance of the Oracle database. , which can be easily viewed through the methods introduced above.
The above is the detailed content of How to view oracle database. For more information, please follow other related articles on the PHP Chinese website!

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