How to query all users in oracle
In Oracle, you can use the select statement to query all users. This statement is used to select data from the database and store the results in a result set. Use "dba_users" to represent all users in the database. Syntax is "select * from dba_users;".
The operating environment of this tutorial: Windows 10 system, Oracle 11g version, Dell G3 computer.
How to query all users in oracle
Query all user information in oracleselect*fromdba_users;
View all users:
select * from dba_users;
View all users in the database, provided that you have an account with DBA authority, such as sys, system
select * from all_users;
View all users you can manage
select * from user_users;
View current user information
Expand knowledge:
View user or role system permissions (system permissions directly assigned to users or roles):
select * from dba_sys_privs; select * from user_sys_privs; (查看当前用户所拥有的权限)
View roles (only view Permissions contained in the roles owned by the logged in user)
sql>select * from role_sys_privs;
View user object permissions:
select * from dba_tab_privs; select * from all_tab_privs; select * from user_tab_privs;
View all roles:
select * from dba_roles;
View the roles owned by the user or role:
select * from dba_role_privs; select * from user_role_privs;
Check which users have sysdba or sysoper system permissions (corresponding permissions are required when querying)
select * from V$PWFILE_USERS
Check the permissions owned by a user in SqlPlus
SQL>select * from dba_sys_privs where grantee='username';
where username is the user name It has to be capitalized.
For example:
SQL>select * from dba_sys_privs where grantee='TOM';
How to delete all tables of a specified user in Oracle
select 'Drop table '||table_name||';' from all_tables where owner='要删除的用户名(注意要大写)';
Recommended tutorial: "Oracle Video Tutorial"
The above is the detailed content of How to query all users in oracle. For more information, please follow other related articles on the PHP Chinese website!

Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics



Oracle View Encryption allows you to encrypt data in the view, thereby enhancing the security of sensitive information. The steps include: 1) creating the master encryption key (MEk); 2) creating an encrypted view, specifying the view and MEk to be encrypted; 3) authorizing users to access the encrypted view. How encrypted views work: When a user querys for an encrypted view, Oracle uses MEk to decrypt data, ensuring that only authorized users can access readable data.

Uninstall method for Oracle installation failure: Close Oracle service, delete Oracle program files and registry keys, uninstall Oracle environment variables, and restart the computer. If the uninstall fails, you can uninstall manually using the Oracle Universal Uninstall Tool.

Deleting all data in Oracle requires the following steps: 1. Establish a connection; 2. Disable foreign key constraints; 3. Delete table data; 4. Submit transactions; 5. Enable foreign key constraints (optional). Be sure to back up the database before execution to prevent data loss.

Oracle Invalid numeric errors may be caused by data type mismatch, numeric overflow, data conversion errors, or data corruption. Troubleshooting steps include checking data types, detecting digital overflows, checking data conversions, checking data corruption, and exploring other possible solutions such as configuring the NLS_NUMERIC_CHARACTERS parameter and enabling data verification logging.

Solutions to Oracle cannot be opened include: 1. Start the database service; 2. Start the listener; 3. Check port conflicts; 4. Set environment variables correctly; 5. Make sure the firewall or antivirus software does not block the connection; 6. Check whether the server is closed; 7. Use RMAN to recover corrupt files; 8. Check whether the TNS service name is correct; 9. Check network connection; 10. Reinstall Oracle software.

Oracle database paging uses ROWNUM pseudo-columns or FETCH statements to implement: ROWNUM pseudo-columns are used to filter results by row numbers and are suitable for complex queries. The FETCH statement is used to get the specified number of first rows and is suitable for simple queries.

The method to solve the Oracle cursor closure problem includes: explicitly closing the cursor using the CLOSE statement. Declare the cursor in the FOR UPDATE clause so that it automatically closes after the scope is ended. Declare the cursor in the USING clause so that it automatically closes when the associated PL/SQL variable is closed. Use exception handling to ensure that the cursor is closed in any exception situation. Use the connection pool to automatically close the cursor. Disable automatic submission and delay cursor closing.

In Oracle, the FOR LOOP loop can create cursors dynamically. The steps are: 1. Define the cursor type; 2. Create the loop; 3. Create the cursor dynamically; 4. Execute the cursor; 5. Close the cursor. Example: A cursor can be created cycle-by-circuit to display the names and salaries of the top 10 employees.
