how to get the field name and value from a record dynamically

Question

I have a procedure which receive as input parameter a record with 170 columns (it is based on the structure of a table).

In the procedure I want to call a debugging procedure one of whose parameters is a text string containing all the field names and values of this record.

For example:

CREATE OR REPLACE PROCEDURE xxx (pi_record IN table_name%ROWTYPE) as
    text VARCHAR2(10000) := NULL;
BEGIN
    ...
    text := 'pi_record.column1 = ' || pi_record.column1 || CHR(13) ||
            'pi_record.column2 = ' || pi_record.column2 || CHR(13) ||
            ...
            'pi_record.column170 = ' || pi_record.column170;
    logging_procedure (text);
    ...
END;

Is there any simple way to achieve this in a dynamic way (looping through record fields names and values) without enumerating all of them?

Maybe something like this:

CREATE OR REPLACE PROCEDURE xxx (pi_record IN table_name%ROWTYPE) as
    text VARCHAR2(10000) := NULL;
BEGIN
    ...      
    LOOP in pi_record.columns
        text := text || CHR(13) || pi_record.column.name || ' : ' || pi_record.column.value
    END LOOP

    logging_procedure (text);
    ...
END; 

Many thanks,

Answer 1

Here's one way to do that. A package spec contains a variable whose type matches the one we'll use in a procedure.

SQL> set serveroutput on
SQL> create or replace package pkg_xxx
  2  as
  3     dept_rec   dept%rowtype;
  4  end;
  5  /

Package created.

SQL> create or replace procedure xxx (pi_record in dept%rowtype)
  2  as
  3     text    varchar2 (10000) := null;
  4     l_str   varchar2 (200);
  5     l_var   varchar2 (200);
  6  begin
  7     pkg_xxx.dept_rec := pi_record;
  8
  9     for cur_r in (  select column_name
 10                       from user_tab_columns
 11                      where table_name = 'DEPT'
 12                   order by column_id)
 13     loop
 14        l_str :=
 15              'begin '
 16           || ':x := to_char(pkg_xxx.dept_rec.'
 17           || cur_r.column_name
 18           || '); '
 19           || 'end; ';
 20
 21        execute immediate l_str using out l_var;
 22
 23        text := text || chr (10) || cur_r.column_name || ' = ' || l_var;
 24     end loop;
 25
 26     dbms_output.put_line (text);
 27  end;
 28  /

Procedure created.

Now, let's pass something to the procedure and see what happens:

SQL> declare
  2     cursor c1
  3     is
  4        select *
  5          from dept
  6         where deptno = 10;
  7
  8     c1r   c1%rowtype;
  9  begin
 10     open c1;
 11     fetch c1 into c1r;
 12     close c1;
 13
 14     xxx (c1r);
 15  end;
 16  /

DEPTNO = 10
DNAME = ACCOUNTING
LOC = NEW YORK

PL/SQL procedure successfully completed.

SQL>

Huh, kind of works (if that's what you asked). Of course, it is just an example, you'll have to modify it if you want to get something really smart (hint: DATE columns).