231023 Oracle SQL SYNONYM(동의어)

■ SYNONYM(동의어)
    A. 긴객체 이름을 짧은 이름으로 사용하는 객체 
    B. SYNONYM 을 생성하려면 CREATE SYNONYM 시스템 권한이 있어야 한다. 
    
# SYNONYM 시스템 권한 확인.

SELECT * FROM session_privs;

# test 생성 후 확인

CREATE TABLE hr.emp_copy_2023
AS 
SELECT * FROM hr.employees;

SELECT * FROM hr.emp_copy_2023;

# SYNONYM 생성 후 확인
    - CREATE SYNONYM SYNONYM명 FOR 원본테이블명;

CREATE SYNONYM ec2 FOR hr.emp_copy_2023;

SELECT * FROM ec2;

# SYNONYM 확인(user_synonyms) 

SELECT * FROM user_synonyms WHERE table_name = 'EMP_COPY_2023';

# SYNONYM 삭제

DROP SYNONYM ec2;

# SYNONYM 확인(user_synonyms) 

SELECT * FROM user_synonyms WHERE table_name = 'EMP_COPY_2023';

# 권한 부여

GRANT SELECT ON hr.employees TO insa;
GRANT SELECT ON hr.departments TO insa;

# 권한 부여 확인

SELECT * FROM user_tab_privs;