Internal PLSQL Tables Access via SQL. But how ?

Question

Hello,
I want to write the result of a database query in an internal PLSQL Table. After that i would like work with this internal PLSQL Table
in a Package/Procedure/Function.
Important for me is to access the internal Table via SQL because i have to refactor a package wich is working with 46 Database Tables an plain SQL. I
would like to change these DB Tables into internal PLSQL Tables.
I have written a short example wich will explain my approach to solving this problem.
The syntax will be accepted by the Database but my 'dbms_output.put_line' statement at the end is empty or blank.
What do i wrong ? Would be nice if anyone can help me out.
With best regards
Jens
pre work :
create table PERSON_DB_TABLE
(SURNAME  VARCHAR2(50),
LASTNAME VARCHAR2(50));
insert into PERSON_DB_TABLE values
('JENS','FOERSTER');
insert into PERSON_DB_TABLE values
('MAX','MEIER');
insert into PERSON_DB_TABLE values
('MARTHA','MUSTERMANN');
create type PERSON_OBJECT as object (
    SURNAME  VARCHAR2(50),
    LASTNAME VARCHAR2(50));
create type PERSON_NESTED_TABLE as table of PERSON_OBJECT;
now my anonymous block
declare
   v_PERSON_OBJECT        PERSON_OBJECT;
   v_PERSON_NESTED_TABLE  PERSON_NESTED_TABLE;
   v_PERSON_OBJECT_2      PERSON_OBJECT;
begin
   for v_counter in (select SURNAME, LASTNAME into v_PERSON_OBJECT.SURNAME,
                                                                                        v_PERSON_OBJECT.LASTNAME
                              from PERSON_DB_TABLE)
     loop
        v_PERSON_NESTED_TABLE := PERSON_NESTED_TABLE(v_PERSON_OBJECT);
     end loop;
   for v_counter in (select SURNAME, LASTNAME into v_PERSON_OBJECT_2.SURNAME,
                                                                                        v_PERSON_OBJECT_2.LASTNAME
                              from TABLE (v_PERSON_NESTED_TABLE))
     loop
        dbms_output.put_line(v_PERSON_OBJECT_2.LASTNAME);
     end loop; 
end;

Answer 1

1386a7b8-e834-43bf-a0d4-922b548bb70b wrote:
I need this, because my customer didn't like the idea to use Database Tables instead of Variables in the RAM. So he wants this procedure redesigned.
As Mike says, keep this person away from your database.
Customers should not be dictating how to implement technical solutions, they should be providing business and logical requirements.
PL/SQL arrays/collections use expensive PGA memory, taking up valuable server resources.
Copying data from the database to PGA memory to try and process it using PL/SQL is bad design.  SQL is designed specifically for data manipulation using database tables, so it's the ideal way to do process data... directly on database tables.