dellera@ORACLE9I> 
dellera@ORACLE9I> -- place you db-link name here
dellera@ORACLE9I> define db_link=loopback
dellera@ORACLE9I> 
dellera@ORACLE9I> -- create local tables as a mirror of the remote ones
dellera@ORACLE9I> create table t1_local as select * from t1@&db_link. where 1=0;
old   1: create table t1_local as select * from t1@&db_link. where 1=0
new   1: create table t1_local as select * from t1@loopback where 1=0

Table created.

dellera@ORACLE9I> create table t2_local as select * from t2@&db_link. where 1=0;
old   1: create table t2_local as select * from t2@&db_link. where 1=0
new   1: create table t2_local as select * from t2@loopback where 1=0

Table created.

dellera@ORACLE9I> 
dellera@ORACLE9I> -- fill remote tables with test data
dellera@ORACLE9I> delete from t1@&db_link.;
old   1: delete from t1@&db_link.
new   1: delete from t1@loopback

0 rows deleted.

dellera@ORACLE9I> delete from t2@&db_link.;
old   1: delete from t2@&db_link.
new   1: delete from t2@loopback

0 rows deleted.

dellera@ORACLE9I> insert into t1@&db_link. (x) values (1);
old   1: insert into t1@&db_link. (x) values (1)
new   1: insert into t1@loopback (x) values (1)

1 row created.

dellera@ORACLE9I> insert into t2@&db_link. (x) values (2);
old   1: insert into t2@&db_link. (x) values (2)
new   1: insert into t2@loopback (x) values (2)

1 row created.

dellera@ORACLE9I> commit;

Commit complete.

dellera@ORACLE9I> 
dellera@ORACLE9I> -- get current remote scn
dellera@ORACLE9I> variable scn number
dellera@ORACLE9I> exec :scn := as_of_scn_views_pkg.get_remote_scn@&db_link.;

PL/SQL procedure successfully completed.

dellera@ORACLE9I> 
dellera@ORACLE9I> -- create as-of-scn views
dellera@ORACLE9I> begin
  2    as_of_scn_views_pkg.create_as_of_scn_view@&db_link. ('t1', 't1_scn_view', :scn);
  3    as_of_scn_views_pkg.create_as_of_scn_view@&db_link. ('t2', 't2_scn_view', :scn);
  4  end;
  5  /
old   2:   as_of_scn_views_pkg.create_as_of_scn_view@&db_link. ('t1', 't1_scn_view', :scn);
new   2:   as_of_scn_views_pkg.create_as_of_scn_view@loopback ('t1', 't1_scn_view', :scn);
old   3:   as_of_scn_views_pkg.create_as_of_scn_view@&db_link. ('t2', 't2_scn_view', :scn);
new   3:   as_of_scn_views_pkg.create_as_of_scn_view@loopback ('t2', 't2_scn_view', :scn);

PL/SQL procedure successfully completed.

dellera@ORACLE9I> show errors;
No errors.
dellera@ORACLE9I> 
dellera@ORACLE9I> -- delete from remote tables
dellera@ORACLE9I> delete from t1@&db_link.;
old   1: delete from t1@&db_link.
new   1: delete from t1@loopback

1 row deleted.

dellera@ORACLE9I> delete from t2@&db_link.;
old   1: delete from t2@&db_link.
new   1: delete from t2@loopback

1 row deleted.

dellera@ORACLE9I> commit;

Commit complete.

dellera@ORACLE9I> 
dellera@ORACLE9I> -- copy data from the consistent image
dellera@ORACLE9I> insert /*+ append */ into t1_local select * from t1_scn_view@&db_link.;
old   1: insert /*+ append */ into t1_local select * from t1_scn_view@&db_link.
new   1: insert /*+ append */ into t1_local select * from t1_scn_view@loopback

1 row created.

dellera@ORACLE9I> commit;

Commit complete.

dellera@ORACLE9I> insert /*+ append */ into t2_local select * from t2_scn_view@&db_link.;
old   1: insert /*+ append */ into t2_local select * from t2_scn_view@&db_link.
new   1: insert /*+ append */ into t2_local select * from t2_scn_view@loopback

1 row created.

dellera@ORACLE9I> commit;

Commit complete.

dellera@ORACLE9I> 
dellera@ORACLE9I> -- show local data
dellera@ORACLE9I> select * from t1_local;

         X
----------
         1

dellera@ORACLE9I> select * from t2_local;

         X
----------
         2

dellera@ORACLE9I> 
dellera@ORACLE9I> spool off