How to view the database in oracle
When using the Oracle database, we need to view the database information and some specific data. So how to view the Oracle database? This article will introduce some practical methods.
1. Use SQL*Plus
SQL*Plus is a command line tool provided by Oracle, through which you can connect to the Oracle database and execute SQL commands. After connecting to the database, we can use the following command to view database-related information:
Query database version number:
SELECT * FROM v$version;
Query database instance name:
SELECT INSTANCE_NAME FROM v$instance;
Query table space:
SELECT TABLESPACE_NAME, TOTAL_SPACE, USED_SPACE, FREE_SPACE FROM DBA_FREE_SPACE;
Query data files:
SELECT FILE_NAME, FILE_ID, TABLESPACE_NAME, BYTES, STATUS FROM DBA_DATA_FILES;
2. Use Oracle Enterprise Manager
Oracle Enterprise Manager is a web-based graphical interface tool that can be used to manage and monitor Oracle databases . Use it to easily view various information in the database. In Oracle Enterprise Manager, we can view database related information through the following steps:
1. Enter the Oracle Enterprise Manager website.
2. Select "Database" in the left column.
3. Select "Instance" in the drop-down menu.
4. In the "Instance" page, you can see the name, version, status and other information of the database.
5. To view more information, you can click the "Performance" tab to view the performance data of the database.
3. Use Oracle SQL Developer
Oracle SQL Developer is a free data modeling and SQL development tool provided by Oracle. Compared with SQL*Plus, it provides a more intuitive graphical user interface and richer functions. In Oracle SQL Developer, we can use the following steps to view database related information:
1. Open Oracle SQL Developer.
2. Select "Database" in the left column.
3. Select the database instance to connect to.
4. In the "Object Browser" you can view various information about the database, including table spaces, data files, users, roles, etc.
5. To view more information, you can select the "Reports" tab on the menu bar and select the corresponding report.
Summary:
The above are three commonly used methods to view Oracle database. Different methods have different advantages and disadvantages, and you can choose the appropriate method according to the specific situation. Whether it is SQL*Plus, Oracle Enterprise Manager or Oracle SQL Developer, they all allow us to manage and monitor Oracle databases more conveniently.
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