Test a database link

Question

Hi
I have a database link which sometimes get problems of disconnection. Generally it works fine. I want to have a method to test the functioning of the database link through PL/SQL or sqlplus command.
Thanks

Answer 1

user2931261 wrote:
Hi
I have a database link which sometimes get problems of disconnection. Generally it works fine. I want to have a method to test the functioning of the database link through PL/SQL or sqlplus command.
Thanksyou can check count(*) of any table present in another database schema.
eg:- select count(*) from test_tb@db_link_name;
SQL> select name from v$database;
NAME
DBDEMO
SQL> create user testing identified by passwd;
User created.
SQL> grant connect,resource to testing;
Grant succeeded.
SQL> conn testing/passwd;
Connected.
SQL> create table test_tb (id number);
Table created.
SQL> insert into test_tb values(123);
1 row created.
SQL> /
1 row created.
SQL> commit;
Commit complete.
SQL> select count(*) from test_tb;
  COUNT(*)
         2
SQL>
on dblink created machine:-
SQL> select name from v$database;
NAME
DB2
SQL> create user nic identified by nic;
User created.
SQL> grant connect,resource, create database link to nic;
Grant succeeded.
SQL> conn nic/nic;
Connected.
SQL> create database link test_db_link connect to testing identified by passwd using '(DESCRIPTION = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.1)(PORT = 1521)) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = dbdemo)))
  2  ';
Database link created.
SQL> select count(*) from test_tb@test_db_link;
  COUNT(*)
         2
SQL>