[Oracle] Oracle如何实现跨库查询

create public database link dblink
  connect to totalplant identified by totalplant 
  using '(DESCRIPTION =
  (ADDRESS_LIST =
   (ADDRESS = (PROTOCOL = TCP)(HOST = LOCALHOST)(PORT = 1521))
  )
  (CONNECT_DATA =
   (SERVICE_NAME = prd.gdc)
  )
  )';

using '(DESCRIPTION =
     (ADDRESS_LIST =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 要连接的数据库所在服务器的IP地址)(PORT = 1521))
     )
     (CONNECT_DATA =
    (SERVICE_NAME = 要连接的数据库的在本地的服务名(即要连接的数据库的SID))
     )
     )';

create database link dblink
  connect to totalplant identified by totalplant 
  using '(DESCRIPTION =
  (ADDRESS_LIST =
   (ADDRESS = (PROTOCOL = TCP)(HOST = LOCALHOST)(PORT = 1521))
  )
  (CONNECT_DATA =
   (SERVICE_NAME = prd.gdc)
  )
  )';

select * from tbl_ost_notebook@dblink;

select * from dba_db_links;

SELECT DISTINCT PRIVILEGE AS "Database Link Privileges"
  FROM ROLE_SYS_PRIVS
  WHERE PRIVILEGE IN ( 'CREATE SESSION','CREATE DATABASE LINK',
    'CREATE PUBLIC DATABASE LINK');