Error Executing a Function

Question

Environment: Oracle 10gR2 on Windows Server 2008 (64-bit)
I have created this Function:
-- ===========================================================================
-- Function: f_delete_gl_account
-- Author: Carol Burrows, dbcSMARTsoftware Inc.
-- Translation: Murray Sobol, dbcSMARTsoftware Inc.
-- Purpose: This is a database Function which deletes a
-- GL_Account_Nbr from all tables.
-- Last Modified: Thursday May 27, 2010
-- Parameter(s): ac_gl_account_nbr varchar2(75) (GL_Acct_Nbr)
-- Return Code(s): SUCCESS 1
-- ERROR -1 -> Cannot get GL_Acct_Nbr
-- -225 -> Cannot delete s1_gl_account_posting records
-- -226 -> Cannot delete s1_gl_account records
-- -99 -> Abnormal termination
-- ===========================================================================
CREATE or replace FUNCTION f_delete_gl_account
(ac_gl_account_nbr IN varchar)
RETURN NUMBER
IS
lc_gl_account_nbr varchar2(75);
c number;
rows_deleted number;
BEGIN
IF (ac_gl_account_nbr IS NULL) THEN
RETURN (-1);
END IF;
lc_gl_account_nbr := ac_gl_account_nbr;
BEGIN
c := DBMS_SQL.OPEN_CURSOR;
DBMS_SQL.PARSE(c, 'DELETE FROM br_gl_account WHERE gl_acct_nbr = ' || lc_gl_account_nbr, DBMS_SQL.NATIVE);
rows_deleted := DBMS_SQL.EXECUTE(c);
dbms_output.put_line('The total number of rows deleted are ' || rows_deleted);
EXCEPTION
WHEN OTHERS THEN
dbms_output.put_line('SQLCODE= ' || SQLCODE);
dbms_output.put_line('SQLERRM= ' || SQLERRM);
dbms_output.put_line('No rows deleted');
RETURN(-2);
END;
BEGIN
c := DBMS_SQL.OPEN_CURSOR;
DBMS_SQL.PARSE(c, 'UPDATE fin_allocation SET allocate_gl_acct_nbr = NULL WHERE allocate_gl_acct_nbr = ' || lc_gl_account_nbr, DBMS_SQL.NATIVE);
rows_deleted := DBMS_SQL.EXECUTE(c);
dbms_output.put_line('The total number of rows updated are ' || rows_deleted);
EXCEPTION
WHEN OTHERS THEN
dbms_output.put_line('No rows deleted');
RETURN(-3);
END;
BEGIN
c := DBMS_SQL.OPEN_CURSOR;
DBMS_SQL.PARSE(c,'UPDATE fin_allocation ' ||
'SET contra_gl_acct_nbr = NULL ' ||
'WHERE contra_gl_acct_nbr = lc_gl_account_nbr', DBMS_SQL.NATIVE);
EXCEPTION
WHEN OTHERS THEN
dbms_output.put_line('No rows updated');
RETURN(-4);
END;
-- ============================================================
-- All Child data has been deleted, now Delete data from
-- s1_gl_account_posting and s1_gl_account tables
-- ============================================================
BEGIN
c := DBMS_SQL.OPEN_CURSOR;
DBMS_SQL.PARSE(c, 'UPDATE s1_gl_account_posting SET gl_acct_nbr = NULL WHERE gl_acct_nbr = lc_gl_account_nbr', DBMS_SQL.NATIVE);
rows_deleted := DBMS_SQL.EXECUTE(c);
dbms_output.put_line('The total number of rows deleted are ' || rows_deleted);
EXCEPTION
WHEN OTHERS THEN
RETURN(-225);
END;
BEGIN
c := DBMS_SQL.OPEN_CURSOR;
DBMS_SQL.PARSE(c, 'DELETE FROM s1_gl_account WHERE gl_acct_nbr = lc_gl_account_nbr', DBMS_SQL.NATIVE);
rows_deleted := DBMS_SQL.EXECUTE(c);
dbms_output.put_line('The total number of rows deleted are ' || rows_deleted);
EXCEPTION
WHEN OTHERS THEN
RETURN(-226);
END;
-- ============================================================
-- Process finished with SUCCESS
-- ============================================================
RETURN(1);
EXCEPTION
WHEN OTHERS THEN
dbms_output.put_line('SQLCODE= ' || SQLCODE);
dbms_output.put_line('SQLERRM= ' || SQLERRM);
RETURN(-999);
END;
which compiles OK.
When I test it using this SQL:
set serveroutput on
select f_delete_gl_account('1120000-4000-9999') from dual;
I get this error:
F_DELETE_GL_ACCOUNT('1120000-4000-9999')
-2
1 row selected.
SQLCODE= -14551
SQLERRM= ORA-14551: cannot perform a DML operation inside a query
No rows deleted
I am trying to avoid using dynamic SQL; instead I am using DBMS_SQL.OPEN_CURSOR and DBMS_SQL.PARSE
Any assistance would be appreciated.

Answer 1

Murray Sobol wrote:
I removed the last one.
BTW, the purpose of those statements was to show the Oracle error message and text if the Function should fail.
With those lines removed, I have now lost that capability.
I compiled it and tested it as before, the error is now:
F_DELETE_GL_ACCOUNT('1120000-4000-9999')
-999
1 row selected.Not at all true if you removed ALL the "exception when others".
Please go through the examples below, in the first set i use your "exception catching" method. Notice how you have NO IDEA which line number causes the exception.
Then in the second set, i run things the way they should be run, which do you find more informative?
FIRST (bad) SET
TUBBY_TUBBZ?exec :x := 0;
PL/SQL procedure successfully completed.
Elapsed: 00:00:00.00
begin
  2 
   if :x = 0
   then
      raise no_data_found;
   end if;
   if :x = 1
   then
      raise too_many_rows;
   end if;
exception
   when others then
      dbms_output.put_line('SQLCODE= ' || SQLCODE);
      dbms_output.put_line('SQLERRM= ' || SQLERRM);  
end;
SQLCODE= 100
SQLERRM= ORA-01403: no data found
PL/SQL procedure successfully completed.
Elapsed: 00:00:00.15
TUBBY_TUBBZ?TUBBY_TUBBZ?   exec :x := 1;
PL/SQL procedure successfully completed.
Elapsed: 00:00:00.00
begin
  2 
   if :x = 0
   then
      raise no_data_found;
   end if;
   if :x = 1
   then
      raise too_many_rows;
   end if;
exception
   when others then
      dbms_output.put_line('SQLCODE= ' || SQLCODE);
      dbms_output.put_line('SQLERRM= ' || SQLERRM);  
end;
SQLCODE= -1422
SQLERRM= ORA-01422: exact fetch returns more than requested number of rows
PL/SQL procedure successfully completed.
Elapsed: 00:00:00.00SECOND (gooder) set
TUBBY_TUBBZ?TUBBY_TUBBZ?   exec :x := 0;
PL/SQL procedure successfully completed.
Elapsed: 00:00:00.00
begin
  2 
   if :x = 0
   then
      raise no_data_found;
   end if;
   if :x = 1
   then
      raise too_many_rows;
   end if;
end;
begin
ERROR at line 1:
ORA-01403: no data found
ORA-06512: at line 5
Elapsed: 00:00:00.01
TUBBY_TUBBZ?TUBBY_TUBBZ?   exec :x := 1;
PL/SQL procedure successfully completed.
Elapsed: 00:00:00.00
begin
  2 
   if :x = 0
   then
      raise no_data_found;
   end if;
   if :x = 1
   then
      raise too_many_rows;
   end if;
end;
begin
ERROR at line 1:
ORA-01422: exact fetch returns more than requested number of rows
ORA-06512: at line 10
Elapsed: 00:00:00.01
TUBBY_TUBBZ?TUBBY_TUBBZ?   Please keep in mind this is trivial for tiny blocks like i'm demonstrating with, but imagine a procedure making many nested procedure calls, each procedure being 100's of lines long.