创建 pulic dblink 使不同的用户可以访问dblink

1.

system:

grant create public database link to ivrsdata;

2.
userdate: tnsnames.ora config db connect_info

drop  database link NGENRO;  
create public database link   NGENRO   connect to IVRSUSR IDENTIFIED by ivrsusr_uat1 using 'db';