What is a DB link in Oracle?

A database link is a pointer that defines a one-way communication path from an Oracle Database server to another database server. The link pointer is actually defined as an entry in a data dictionary table. To access the link, you must be connected to the local database that contains the data dictionary entry.

How do I find the DB link in Oracle?

Any user can query USER_DB_LINKS to determine which database links are available to that user. Only those with additional privileges can use the ALL_DB_LINKS or DBA_DB_LINKS view.

How do I create a database link between two Oracle databases?

Oracle CREATE DATABASE LINK statement

  1. First, specify the name of the database link after the CREATE DATABASE LINK keywords.
  2. Second, provide user and password of the remote database after the CONNECT TO and IDENTIFIED BY keywords.
  3. Finally, specify the service name of the remote database.

How do you create a database link?

To create a private database link, you must have the CREATE DATABASE LINK system privilege. To create a public database link, you must have the CREATE PUBLIC DATABASE LINK system privilege. Also, you must have the CREATE SESSION system privilege on the remote Oracle database.

How do you check the DB Link is working or not?

We can verify public database link using select * from dual@public_db_link; How private db links can be verified by a DBA if application schema’s password is not known.

How do I create a database link in another schema?

Simple solution is to create anonymous block which will first create dummy function in another schema and then reuse it to create or drop an object(in our case database link). Of course it can be reused to do other types of object as well. SQL> CONNECT / AS SYSDBA Connected.

How to use dblink in Oracle Database?

Specify the complete or partial name of the database link. If you specify only the database name, then Oracle Database implicitly appends the database domain of the local database. Use only ASCII characters for dblink. Multibyte characters are not supported. The database link name is case insensitive and is stored in uppercase ASCII characters.

How do I create a link between two databases in Oracle?

CREATE DATABASE LINK. Use the CREATE DATABASE LINK statement to create a database link. A database link is a schema object in one database that enables you to access objects on another database. The other database need not be an Oracle Database system.

What domain does Oracle use when creating a database link?

If no domain name is explicitly specified, Oracle uses the domain of the database in which the link is being created. Oracle documentation for database link creation:

How to create a public database link in Oracle Net?

To create a public database link, you must have the CREATE PUBLIC DATABASE LINK system privilege. Also, you must have the CREATE SESSION system privilege on the remote Oracle database. Oracle Net must be installed on both the local and remote Oracle databases.