Oracle Inner Join with Collection?

Question

I want to join collection of table type with other tables in following example -

I have a function F_GetPendingFeeds which returns the table collection of type feed_log. I want to join this returning collection with one of the table -

CREATE OR REPLACE PACKAGE BODY L_DemoPkg
IS
   TYPE t_feedLog IS TABLE OF feed_log%ROWTYPE
                INDEX BY PLS_INTEGER;

   FUNCTION F_GetPendingFeeds
      RETURN t_feedLog
   IS
   lo_feedLog t_feedLog;
   BEGIN
      SELECT feed_log_seq
         , processed_dt
         , processed_by
         , create_dt
         , created_by
      BULK COLLECT INTO lo_feedLog
      FROM feed_log
      WHERE status_cd = 0;

      RETURN lo_feedLog;

   EXCEPTION
      WHEN OTHERS THEN
         --TODO: Log Exception
         RAISE;
   END F_GetPendingFeeds;


   PROCEDURE P_ProcessFeed
   IS
   o_pendingFeed t_feedLog;
   ln_totalRecords t_feedLog;

   BEGIN

      -- Get the list of pending feed ids
      o_pendingFeed := F_GetPendingFeeds();

      -- Check if new data is present for processing
      IF o_pendingFeed.COUNT = 0 THEN
         dbms_output.put_line('Feed processing failed. No data found.');
         RETURN;
      END IF;

      SELECT COUNT(*)
      INTO ln_totalRecords
      FROM  feed_details t1
          , table(o_pendingFeed) t2 --ERROR: ORA-22905: cannot access rows from a non-nested table item
      WHERE t1.feed_log_seq = t2.feed_log_seq;

   EXCEPTION
      WHEN OTHERS THEN
         --TODO: Log Exception
         RAISE;
   END P_ProcessFeed;
END;

I am receiving error as -

PL/SQL: SQL Statement ignored
PL/SQL: ORA-22905: cannot access rows from a non-nested table
     item

Please notice that I want to join collection with table -

  FROM  feed_details t1
      , table(o_pendingFeed) t2 --ERROR: ORA-22905: cannot access rows from a non-nested table item   WHERE t1.feed_log_seq = t2.feed_log_seq;

Answer 1

Prior to Oracle 12C you could only select from collections that have been created on the server using CREATE TYPE e.g.

SQL> CREATE TYPE r_feedLog IS OBJECT (foo NUMBER, bar VARCHAR2(20));
SQL> CREATE TYPE t_feedLog IS TABLE OF r_feedLog;

Then remove the declaration of t_feedLog from your package.

With Oracle 12C it is possible to select from PL/SQL tables defined in a package specification.

Answer 2

you have several errors here. Firstly, to access an array in a TABLE cast you need to use a SQL array (well, you could use a PL/SQL table still, but that only works for a pipelined function, as Oracle will create the SQL types silently for you; but even in that case its still neater to use a SQL array). so you'd need to do:

SQL> create type r_feedlog is object
  2  (
  3    feed_log_seq number,
  4     processed_dt date,
  5    processed_by varchar2(10),
  6    create_dt date,
  7    created_by varchar2(10)
  8  );
  9  /

Type created.

SQL> create type t_feedLog as table of r_feedlog;
  2  /

Type created.

and then use that and NOT a pl/sql index-by table. secondly

   ln_totalRecords t_feedLog;

should be a number not a collection as your selecting count(*) into it. Also :

  BULK COLLECT INTO lo_transferFeedDef

should be

  BULK COLLECT INTO lo_feedLog 

you could have the function as pipelined of course i.e. something like:

CREATE OR REPLACE PACKAGE L_DemoPkg
as
  type r_feedlog is record(feed_log_seq number,
                           processed_dt date,
                           processed_by varchar2(10),
                           create_dt date,
                           created_by varchar2(10));
  type t_feedLog is table of r_feedlog;

  function F_GetPendingFeeds return t_feedLog pipelined;

  procedure P_ProcessFeed;
end;
/

and within the package body:

FUNCTION F_GetPendingFeeds
   RETURN t_feedLog pipelined
IS
lo_feedLog r_feedlog;
BEGIN
   for r_row in (SELECT feed_log_seq
                        , processed_dt
                        , processed_by
                        , create_dt
                        , created_by
                   FROM feed_log
                  WHERE status_cd = 0)
   loop
     lo_feedLog.feed_log_seq := r_row.feed_log_seq;
     lo_feedLog.processed_dt := r_row.processed_dt;
     lo_feedLog.processed_by := r_row.processed_by;
     lo_feedLog.create_dt := r_row.create_dt;
     lo_feedLog.created_by := r_row.created_by;
     pipe row(lo_feedLog);
   end loop;
END F_GetPendingFeeds;

within the procedure you could then just:

SELECT COUNT(*)
INTO ln_totalRecords
FROM  feed_details t1
    , table(F_GetPendingFeeds()) t2
WHERE t1.feed_log_seq = t2.feed_log_seq;

The above was keeping a pl/sql array. if you had the SQL array, the function would be a bit more compact:

FUNCTION F_GetPendingFeeds
   RETURN t_feedLog pipelined
IS
BEGIN
   for r_row in (SELECT r_feedlog(feed_log_seq
                        , processed_dt
                        , processed_by
                        , create_dt
                        , created_by) data
                   FROM feed_log
                  WHERE status_cd = 0)
   loop
     pipe row(r_row.data);
   end loop;
END F_GetPendingFeeds;