Oracle queries the current user for information

First, view the current user information:
1. View the current user-owned Role Permissions information: SELECT * from Role_sys_privs;
2. View the details of the current User: SELECT * from User_users;
3. View the current user's role information: SELECT * from User_role_privs;

Summary: The data dictionary view in Oracle is divided into 3 categories, with prefixes distinguished by: User,all and DBA,
Many data dictionary views contain similar information.

User_*: Information about the object that the user owns, that is, the object information that the user creates.
All_*: Information about the objects that the user can access, that is, the information that the user creates for the object, plus the other user-created object but the user has permission to access the information.
Dba_*: Information about an object in the entire database.

Other:
View the relationship between the user and the default tablespace.
Select Username,default_tablespace from Dba_users;
1. View table structure: DESC table name
2. View the table for the current user:
Select table_name from User_tables;
3. View the table names for all users:
Select table_name from All_tables;
4. View all table names (including system tables)
Select table_name from All_tables;
5. View all the tables:
SELECT * from Tab/dba_tables/dba_objects/cat;


The following describes the Oracle query user table space

Oracle Query User Table space: SELECT * from User_all_tables

Oracle queries all functions and stored procedures: SELECT * FROM User_source

Oracle Queries All users: SELECT * FROM All_users.select * from Dba_users

Oracle View Current User connection: SELECT * from V$session

Oracle View Current User rights: SELECT * FROM Session_privs

Oracle View User table space usage:

Select a.file_id "Fileno", A.tablespace_name

"Tablespace_name",

A.bytes "bytes", A.bytes-sum (NVL (b.bytes,0)) "used",

Sum (NVL (b.bytes,0)) "Free",

Sum (NVL (b.bytes,0))/a.bytes*100 "%free"

From Dba_data_files A, dba_free_space b

where a.file_id = B. file_id (+)

Group BY A.tablespace_name,

A.file_id,a.bytes ORDER by A.tablespace_name;

1. View All Users:
SELECT * from Dba_user;

SELECT * from All_users;

SELECT * from User_users;

2. View User system permissions:
SELECT * from Dba_sys_privs;

SELECT * from All_sys_privs;

SELECT * from User_sys_privs;

3. View User Object permissions:
SELECT * from Dba_tab_privs;

SELECT * from All_tab_privs;

SELECT * from User_tab_privs;

4. View all roles:
SELECT * from Dba_roles;

5. View the roles owned by the user:
SELECT * from Dba_role_privs;

SELECT * from User_role_privs;

6. View the permissions that the role has:
SELECT * from Role_sys_privs;

SELECT * from Role_tab_privs;
7. View all system permissions
SELECT * from System_privilege_map;

8. View all object permissions
SELECT * from Table_privilege_map;

The above is to view the user rights in Oracle,


In the DB2:


SELECT * FROM Syscat.dbauth
Or
Get authorizations

View SIDs
SELECT * FROM V$instance

Oracle queries the current user for information