How to query all libraries in Oracle
Oracle is a relational database management system. It is an open database and can provide highly reliable, efficient and scalable functions. When using Oracle, querying all libraries is a very important and common operation. This article will introduce how to query all libraries in Oracle.
Query operations for all libraries in Oracle can be completed in Oracle's SQL Developer. First, you need to connect to the Oracle instance, enter the SQL Developer interface and select "File"-"New"-"Database Connection". In the opened connection window, fill in the connection information, including user name, password, host name, port number, service name, and then click the "Test" button to test whether the connection is successful. If you successfully connect to the Oracle instance, you can now view all databases as well as tables and other objects owned by all users.
View all libraries in SQL Developer, which can be achieved in the following ways.
Method 1: Use SQL query
1. In the SQL Developer environment, enter SQL Worksheet.
2. Enter the SQL query statement as follows:
SELECT DISTINCT owner FROM all_tables;
3. Run the query statement and you can see the names of all users. Each user corresponds to a database.
4. You can use the query statement to obtain the names of all databases owned by each user, as follows:
SELECT DISTINCT tablespace_name FROM dba_data_files;
Method 2: Use Oracle Enterprise Manager
Oracle Enterprise Manager is a web console through which you can manage Oracle databases. The method to view all libraries in Oracle Enterprise Manager is as follows.
1. First log in to Oracle Enterprise Manager.
2. Select "Targets"-"All Targets" on the homepage.
3. Then select the "Database" tab and select the "Oracle" tab.
4. All database instances on the Oracle server will be listed at this time.
5. Click on the database instance you want to view and select "Schema" at the top of the page.
6. All users and databases under this database instance will be listed at the bottom of the page.
Summary
Querying all libraries in Oracle is a relatively simple operation, which can be achieved through SQL query statements and Oracle Enterprise Manager. In actual applications, specific query operations will vary depending on the database involved and operational requirements. I hope that the introduction in this article can be helpful to everyone and allow everyone to better understand the method of querying all libraries in Oracle.
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