ORA-14451 : Can't do DML inside a select : PL/SQL Question

Question

I was just wondering if anyone had an answer to this little conundrum.
I've got a PL/SQL function in a package which has an insert statement inside it which I only
want to perform the insert if it's called from another PL/SQL procedure or function
but not do the insert if it's used in a select statement.
Does anyone know if you can work out the context in which a function is being called within
the function as it would generally be cleaner if I only had one implementation rather than one
for each context.
Not desparately important but it would be nice to know....
Thanks,
Rob

Answer 1

I don't know what the fuss it about -- but -- it seems to work for me. And I can think of a place where this would be useful. In an Oracle (ERP) Applications Alert. Alerts are limited and being able to SELECT and UPDATE a table, from inside the SELECT is useful. SQL Rules are for people who follow rules [HA :) ]
SQL> CREATE TABLE TEST
  2  (      Id      Number
  3  ,      Num1      NUMBER
  4  );
Table created.
SQL> CREATE TABLE TEST2
  2  (      Id      Number
  3  ,      Num1      NUMBER
  4  );
Table created.
SQL>
SQL> INSERT INTO TEST ( Id, Num1 ) VALUES ( 1, 1 );
1 row created.
SQL> INSERT INTO TEST ( Id, Num1 ) VALUES ( 2, 2 );
1 row created.
SQL> INSERT INTO TEST ( Id, Num1 ) VALUES ( 3, 3 );
1 row created.
SQL>
SQL> CREATE OR REPLACE PACKAGE TEST_PK
  2  IS
  3        FUNCTION Return_X RETURN VARCHAR2;
  4  END;
  5  /
Package created.
SQL> show errors package test_pk;
No errors.
SQL>
SQL> CREATE OR REPLACE PACKAGE BODY TEST_PK
  2  IS
  3        FUNCTION Return_X
  4            RETURN VARCHAR2
  5        IS
  6        PRAGMA AUTONOMOUS_TRANSACTION;
  7        BEGIN
  8            INSERT INTO TEST2 ( Id, Num1 ) VALUES ( 21, 21 );
  9            COMMIT;
10            RETURN 'X';
11        END Return_X;
12
13  END;
14  /
Package body created.
SQL> show errors package body test_pk;
No errors.
SQL>
SQL> SELECT TEST_PK.Return_X AS Test_Thing FROM TEST;
TEST_THING
X
X
X
SQL>
SQL> SELECT * FROM TEST2;
       ID      NUM1
       21        21
       21        21
       21        21