Sorting Data at the runtime in Oracle PL/SQL using Associative array - oracle

Question

I am trying to sort a data from runtime query and no way I can do that without use of a collection. Essentially, I have 2 columns in Service table - SERVICE_ID, SERVICE_NAME. I have created an Associative array in a package so that I can use it in my procedure.
TYPE g_vc_arr IS TABLE OF VARCHAR2(4000) INDEX BY PLS_INTEGER;
In my pl/sql block I am creating a variable like below:
service_list my_pkg.g_vc_arr;
I am assigning the SERVICE_ID and SERVICE_NAME to this variable like below:
LOOP
service_list(services.SERVICE_ID) := services.SERVICE_NAME;
END LOOP;
Now, I am using this to sort the name column like below snippet. I am able to print the name but in this process, I am losing the ID.
for query_result_row in (SELECT * from table(service_list) order by 1) loop
dbms_output.put_line(query_result_row.COLUMN_VALUE);
end loop;
I need both ID and NAME to process further. How can I get both?

Answer 1

As others have mentioned, you don't need to sort it as it is already held in the order you defined it:
create or replace package demo
as
type currency_tt is table of varchar2(3) index by pls_integer;
currencies demo.currency_tt :=
demo.currency_tt
( 1 => 'USD'
, 2 => 'GBP'
, 3 => 'EUR' );
end demo;
begin
for r in (
select * from table(demo.currencies)
)
loop
dbms_output.put_line(r.column_value);
end loop;
end;
Output:
USD
GBP
EUR
But you don't need SQL, as you can iterate over an associative array procedurally:
declare
i pls_integer := demo.currencies.first;
begin
while i is not null loop
dbms_output.put_line(i||' '||demo.currencies(i));
i := demo.currencies.next(i);
end loop;
end;
Or from 21c you can loop more conveniently like this:
begin
for id, ccy in pairs of demo.currencies loop
dbms_output.put_line(id || ' '|| ccy);
end loop;
end;
1 USD
2 GBP
3 EUR

Answer 2

I changed my approach a bit to solve this issue. I created a package with 2 column TYPE as record and an associative array of the record type:
create or replace package my_pkg is
TYPE g_rec_type IS RECORD (ID NUMBER, name VARCHAR2(4000));
TYPE g_rec_arr IS TABLE OF g_rec_type INDEX BY PLS_INTEGER;
end my_pkg;
In my actual PL/sqL block I created couple of variables:
i NUMBER := 0;
service_list MY_PKG.g_rec_arr;
Then I created a loop to assign the values to array:
LOOP
service_list(i).ID := services.SERVICE_ID;
service_list(i).NAME := services.SUMMARY;
i := i+1;
END LOOP;
Further to sort the value I used following:
FOR query_result_row in (SELECT ID, NAME from table(service_list) order by NAME) LOOP
dbms_output.put_line('ID is =>' || query_result_row.ID|| ' Name is =>' || query_result_row.NAME);
END LOOP;
And it worked as expected.