create database link GTPROD_CONNECT.WORLD connect to local identified by local using '(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=172.16.85.144)(PORT = 1521)))(CONNECT_DATA =(SID = orcl)(SERVER = 192.168.0.13)))' select * from EXDB.DC_MINGZHENG_PROVIDE@GTPROD_CONNECT.WORLD