* Beware of the issues with calinng PL/SQL function from SQL


The requirements
----------------------


The restrictions
-------------------
* Thou shall not change the database...No DML, DDL allowed in the function.

SQL> create or replace function my_func_ return number as
  2  begin
  3  delete from t1_;
  4  end;
  5  /

Function created.

SQL> select my_func_  from dual;
select my_func_  from dual
       *
ERROR at line 1:
ORA-14551: cannot perform a DML operation inside a query
ORA-06512: at "JYANG.MY_FUNC_", line 3


SQL> 

SQL> create or replace function fun1_ return number as
  2  begin
  3  execute immediate 'create table tyu3(c1 number)';
  4  end;
  5  /

Function created.

SQL> select fun1_ from dual;
select fun1_ from dual
       *
ERROR at line 1:
ORA-14552: cannot perform a DDL, commit or rollback inside a query or DML
ORA-06512: at "JYANG.FUN1_", line 3


SQL>