CONNECT TO hr IDENTIFIED BY hr
USING 'orcl';
CREATE PUBLIC SYNONYM emp_table
FORHR.employees@l_hr;
GRANT SELECT ON HR.employees to SCOTT;
conn scott/tiger@orcl
SELECT count(*) from sys.offices;
select count(*) from emp_table;
三、DROP SYNONYM 删除同义词
1、语法结构：
2、前提条件：
To drop a private synonym, either the synonym must be in your own schema or you must have the DROP ANY SYNONYM system privilege.
删除私有同义词需要有DROP ANY SYNONYM权限。
To drop a PUBLIC synonym, you must have the DROP PUBLIC SYNONYM system privilege.
删除公有同义词需要有DROP PUBLIC SYNONYM权限。
3、示例
3.1删除public同义词，必须加public关键字：
SYS@orcl>DROP SYNONYM emp_table;
DROPSYNONYM emp_table
*
第 1 行出现错误:
ORA-01434:要删除的专用同义词不存在
SYS@orcl>DROP PUBLIC SYNONYM emp_table;
同义词已删除。
3.2删除private同义词：
DROP SYNONYM offices;
四、Q&A 问答
Q: 可以对同义词做INSERT/UPDATE/DELETE操作吗？
A:
SCOTT@orcl> UPDATE sys.offices t SETt.city='Shanghai' WHERE location_id=1000;
UPDATE sys.offices t SET t.city='Shanghai'WHERE location_id=1000
*
第 1 行出现错误:
ORA-01031: 权限不足
SYS@orcl> grant update on hr.locationsto scott;
授权成功。
SCOTT@orcl> /
已更新 1 行。
SO: 用户对同义词的操作权限都是基于对其底层对象有哪些操作权限。
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Dylan Presents.