dblink名字后面有字符串REGRESS.RDBMS.DEV.US.ORACLE.COM

SQL>  select * from global_name;

GLOBAL_NAME
--------------------------------------------------------------------------------
ORCL

SQL> create database link to_orcl2 connect to sys identified by oracle using 'ORCL2';

Database link created.

SQL> select * from dba_db_links;

OWNER
------------------------------------------------------------
DB_LINK
--------------------------------------------------------------------------------
USERNAME
------------------------------------------------------------
HOST
--------------------------------------------------------------------------------
CREATED
-------------------
SYS
TO_ORCL2
SYS

2016-02-19 03:03:18

SQL> drop  database link to_orcl2;

Database link dropped.

SQL>  alter database rename global_name to  ORCL.REGRESS.RDBMS.DEV.US.ORACLE.COM;

Database altered.

SQL> create database link to_orcl2 connect to sys identified by oracle using 'ORCL2';

Database link created.

SQL> select * from dba_db_links;

OWNER
------------------------------------------------------------
DB_LINK
--------------------------------------------------------------------------------
USERNAME
------------------------------------------------------------
HOST
--------------------------------------------------------------------------------
CREATED
-------------------
SYS
TO_ORCL2.REGRESS.RDBMS.DEV.US.ORACLE.COM
SYS