How to check which users are in Oracle
How to query the users in Oracle: 1. Execute the "select * from dba_users;" statement; 2. Execute the "select * from all_users;" statement; 3. Execute the "select * from user_users;" statement.
The operating environment of this tutorial: Windows 7 system, Oracle 11g version, Dell G3 computer.
Query all user information in Oracle
1. View all users:
select * from dba_users; select * from all_users; select * from user_users;
2. 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)
3. View roles (only roles owned by logged-in users can be viewed) Contained permissions
sql>select * from role_sys_privs;
4. View user object permissions:
select * from dba_tab_privs; select * from all_tab_privs; select * from user_tab_privs;
5. View all roles:
select * from dba_roles;
6. Check the roles owned by users or roles:
select * from dba_role_privs; select * from user_role_privs;
7. Check which users have sysdba or sysoper system permissions (corresponding permissions are required when querying)
select * from V$PWFILE_USERS
8. Check the permissions owned by a user in SqlPlus
SQL>select * from dba_sys_privs where grantee='username'; 其中的username即用户名要大写才行。 比如: SQL>select * from dba_sys_privs where grantee='TOM';
9. 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)';
10. Delete user
drop user user_name cascade; 如:drop user SMCHANNEL CASCADE
11. Get all tables under the current user:
select table_name from user_tables;
12. Delete all table data under a certain user :
select 'truncate table ' || table_name from user_tables;
13. Foreign key constraints are prohibited. The foreign key constraint names in the ORACLE database can be found in the table user_constraints.
constraint_type='R' indicates a foreign key constraint.
启用外键约束的命令为:alter table table_name enable constraint constraint_name 禁用外键约束的命令为:alter table table_name disable constraint constraint_name
Then use SQL to find out the constraint names of all foreign keys in the database:
select 'alter table '||table_name||' enable constraint '||constraint_name||';' from user_constraints where constraint_type='R'select 'alter table '||table_name||' disable constraint '||constraint_name||';' from user_constraints where constraint_type='R'
14. ORACLE disables/enables foreign keys and triggers - -Enable script
SET SERVEROUTPUT ON SIZE 1000000 BEGIN for c in (select 'ALTER TABLE '||TABLE_NAME||' ENABLE CONSTRAINT '||constraint_name||' ' as v_sql from user_constraints where CONSTRAINT_TYPE='R') loop DBMS_OUTPUT.PUT_LINE(C.V_SQL); begin EXECUTE IMMEDIATE c.v_sql; exception when others then dbms_output.put_line(sqlerrm); end; end loop; for c in (select 'ALTER TABLE '||TNAME||' ENABLE ALL TRIGGERS ' AS v_sql from tab where tabtype='TABLE') loop dbms_output.put_line(c.v_sql); begin execute immediate c.v_sql; exception when others then dbms_output.put_line(sqlerrm); end; end loop; end; / commit;
--Disable script
SET SERVEROUTPUT ON SIZE 1000000 BEGIN for c in (select 'ALTER TABLE '||TABLE_NAME||' DISABLE CONSTRAINT '||constraint_name||' ' as v_sql from user_constraints where CONSTRAINT_TYPE='R') loop DBMS_OUTPUT.PUT_LINE(C.V_SQL); begin EXECUTE IMMEDIATE c.v_sql; exception when others then dbms_output.put_line(sqlerrm); end; end loop; for c in (select 'ALTER TABLE '||TNAME||' DISABLE ALL TRIGGERS ' AS v_sql from tab where tabtype='TABLE') loop dbms_output.put_line(c.v_sql); begin execute immediate c.v_sql; exception when others then dbms_output.put_line(sqlerrm); end; end loop; end; / commit;
Recommended tutorial: "Oracle Tutorial"
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