以下不知道从哪抄的内容，分享给大家。
1.查看所有用户：
select * from dba_users; select * from all_users; select * from user_users;
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2.查看用户或角色系统权限(直接赋值给用户或角色的系统权限)：
select * from dba_sys_privs; --查看当前用户所拥有的权限 select * from user_sys_privs;
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3.查看角色(只能查看登陆用户拥有的角色)所包含的权限
select * from role_sys_privs;
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4.查看用户对象权限：
select * from dba_tab_privs; select * from all_tab_privs; select * from user_tab_privs;
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5.查看所有角色：
select * from dba_roles;
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6.查看用户或角色所拥有的角色：
select * from dba_role_privs; select * from user_role_privs;
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7.查看哪些用户有sysdba或sysoper系统权限(查询时需要相应权限)
select * from V$PWFILE_USERS
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8.SqlPlus中查看一个用户所拥有权限
select * from dba_sys_privs where grantee = 'username'; --其中的username即用户名要大写
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?9.Oracle删除指定用户所有表的方法
select 'Drop table '||table_name||';' from all_tables where owner='要删除的用户名(注意要大写)';
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10.删除用户
drop user user_name cascade;
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?11.获取当前用户下所有的表：
SELECT * FROM ALL_TABLES WHERE OWNER = 'username'; SELECT OWNER,COUNT(*) FROM ALL_TABLES GROUP BY OWNER; SELECT COUNT(*) FROM TABS; SELECT COUNT(*) FROM USER_TABLES; SELECT * FROM DBA_SEQUENCE WHERE SEQUENCE_OWNER='username';
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12.删除某用户下所有的表数据:?
select 'truncate table ' || table_name from user_tables;
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13.禁止外键
ORACLE数据库中的外键约束名都在表user_constraints中可以查到。其中constraint_type='R'表示是外键约束。
--启用外键约束的命令 alter table table_name enable constraint constraint_name; --禁用外键约束的命令 alter table table_name disable constraint constraint_name; --用SQL查出数据库中所以外键的约束名： 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禁用/启用外键和触发器
--启用脚本 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; --禁用脚本 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;?
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