Need to simulate identity behaviour in Oracle

Question

I have 2 tables,Table A and Table B.
I insert tuples into Table A which has its primary column as identity.
I have used SEQUENCE in Oracle to simulate behaviour of identity in MS-SQL Server.
Once I have inserted in table A,I need to access the identity value inserted in
Table A and put it in table B.In short I need something that simulates scope_identity() function in SQL Server....
Could any body suggest something..
Thanks for the help

Answer 1

Something like that works too.
SQL> create table t_a (id number);
Table created.
SQL> create table t_b (id number);
Table created.
SQL> create sequence seq_1;
Sequence created.
SQL> create or replace package pkg_scope
  2  is
  3   type id_scope_tab is table of t_a.id%type index by binary_integer;
  4   function scope_identity(clear boolean) return id_scope_tab;
  5   procedure add_element(id t_a.id%type);
  6  end;
  7  /
Package created.
SQL> create or replace package body pkg_scope
  2  is
  3   id_scope id_scope_tab;
  4   function scope_identity(clear boolean) return id_scope_tab
  5   is
  6    scope id_scope_tab := id_scope;
  7   begin
  8    if clear then
  9     id_scope.delete;
10    end if;
11    return scope;
12   end;
13   procedure add_element(id t_a.id%type)
14   is
15   begin
16    id_scope(id_scope.count+1) := id;
17   end;
18  end;
19  /
Package body created.
SQL> create or replace trigger tr_aifer_t_a
  2  after insert on t_a
  3  for each row
  4  begin
  5   pkg_scope.add_element(:new.id);
  6  end;
  7  /
Trigger created.
SQL> create or replace trigger tr_bifer_t_a
  2  before insert on t_a
  3  for each row
  4  begin
  5   select seq_1.nextval into :new.id from dual;
  6  end;
  7  /
Trigger created.
SQL> insert into t_a values(null);
1 row created.
SQL> /
1 row created.
SQL> /
1 row created.
SQL> select * from t_a;
        ID
         1
         2
         3
SQL> select * from t_b;
no rows selected
SQL> declare
  2   ids pkg_scope.id_scope_tab := pkg_scope.scope_identity(true);
  3  begin
  4   forall i in ids.first..ids.last
  5    insert into t_b values(ids(i));
  6  end;
  7  /
PL/SQL procedure successfully completed.
SQL> select * from t_b;
        ID
         1
         2
         3
SQL> insert into t_a values(null);
1 row created.
SQL> /
1 row created.
SQL> select * from t_a;
        ID
         1
         2
         3
         4
         5
SQL> declare
  2   ids pkg_scope.id_scope_tab := pkg_scope.scope_identity(true);
  3  begin
  4   forall i in ids.first..ids.last
  5    insert into t_b values(ids(i));
  6  end;
  7  /
PL/SQL procedure successfully completed.
SQL> select * from t_b;
        ID
         1
         2
         3
         4
         5Also you can use BULK COLLECT INTO tougether with Kamal's example to
keep a range of values:
SQL> declare
  2   ids pkg_scope.id_scope_tab;
  3   ids_out pkg_scope.id_scope_tab;
  4  begin
  5   for i in 1..3 loop
  6    ids(i) := 0;
  7   end loop;
  8   forall i in 1..3
  9    insert into t_a values(ids(i)) returning id bulk collect into ids_out;
10   forall i in ids_out.first..ids_out.last
11    insert into t_b values(ids_out(i));
12  end;
13  /
PL/SQL procedure successfully completed.
SQL> select * from t_a;
        ID
         1
         2
         3
         4
         5
         6
         7
         8
8 rows selected.
SQL> select * from t_b;
        ID
         1
         2
         3
         4
         5
         6
         7
         8
8 rows selected.Rgds.