Dropping a database link from your Oracle database is as easy as doing the following:

drop database link remotedb;
or
drop public database link remotedb;

You will need no other system privilege other than the ‘create database link’ privilege granted directly
to your username or granted via a role to drop your own database link.

It is not possible to drop a database link belonging to another user.

If you try to specify another schema’s database link by qualifying it with a name,
Oracle will just look for a private database link in your schema with a name
which includes the other schema’s name and will not find it.

To drop a public database link, you will need the system privilege ‘drop public database link’.

For example:

SQL> connect / as sysdba
Connected.

SQL> drop database link scott.remotedb;
drop database link scott.remotedb
                   *
ERROR at line 1:
ORA-02024: database link not found

SQL> connect scott/tiger
Connected.
SQL> drop database link scott.remotedb;
drop database link scott.remotedb
                   *
ERROR at line 1:
ORA-02024: database link not found

SQL> drop database link remotedb;

Database link dropped.

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