dblink

 Dblink is to build a bridge between two databases. Users can connect to database A and use the dblink of database A to access the data of database B.

1. Query the dblink under the currently logged in user

      select * from ALL_DB_LINKS

       The query result is as follows,

     owner: the owner, db_link: the name of the dblink, username: the user name for connecting to database B, host: the address information for connecting to database B.

2. Query all dblinks in the database

select * from dba_db_links

 

3. Delete the dblink of the current user

drop  database link BIMAP;

4. Delete dblinks for all users

drop public database link 名称

5. Create a dblink under the current user

create database link link name connect to database B username identified by password
　　 using '(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = database_ip)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME =servicename)
)
)';

6. Create a public dblink

 

create public database link link name connect to database B username identified by password
　　 using '(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = database_ip)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME =servicename ) )
)
)';