Comments on: Disappearing Columns

By: Remco Blaakmeer

Remco Blaakmeer — Thu, 24 Jun 2010 00:06:02 +0000

Alex,
I just thought of a solution to this problem, with this trigger:
Â
create or replace trigger trg_prevent_create_xmltype
before create
on database
begin
if ora_dict_obj_owner != ‘SYS’
and upper(ora_dict_obj_name) = ‘XMLTYPE’
then
raise_application_error(-20000, ‘Will not create XMLTYPE (ignore this error)’);
end if;
end;
/
Â
This generates an error when you forget to strip the CREATE TYPE statement. This might not be what you want if you execute the DDL from the Design Editor, but I don’t do that anyway.
Â

By: Alex Nuijten

Alex Nuijten — Mon, 29 Jan 2007 12:32:31 +0000

Hi Rachana,
No that is not possible. I can see any praticle use for it either….

SQL>
SQL> set serveroutput on
SQL> begin
2 dbms_output.put_line (sqlerrm (-12983));
3 end;
4 /
ORA-12983: cannot drop all columns in a table

PL/SQL procedure successfully completed.

SQL>

By: Rachana

Rachana — Mon, 29 Jan 2007 05:59:27 +0000

Can we drop all the columns in a table at a time ????????

By: Marco Gralike

Marco Gralike — Sat, 23 Dec 2006 17:08:09 +0000

Bug, SR has been accepted by Oracle on all levels (not only the one shown here). I (but you triggered me, Alex) refer to this one, as my newly discovered (SQL) “Database Injection” bug (because it HAS some security implications, if you think about it…), and is not only data corruption related.

Alex, Harm, follow up can be read the SR via the BetaCSI

By: harm

harm — Fri, 22 Dec 2006 12:08:16 +0000

Although not predefined in Designer, it HAS support for xmltype. You have to create the type yourself as TYPE object. After that you can reference to it in your tables and views and program units.

By: Alex Nuijten

Alex Nuijten — Thu, 21 Dec 2006 09:13:58 +0000

Ah, good point…. you were miles ahead of me, now I understand what you mean. Thank you.

By: Marco Gralike

Marco Gralike — Wed, 20 Dec 2006 20:58:15 +0000

My problem is that it should behave as the following DATE contra XMLTYPE example… (in which the DATE behavior is the recommended one…)

To show that it shouldn’t be happening or it is at least inconsistent behavior, two examples: one with “XMLTYPE” and one with “DATE”…

SQL> CREATE OR REPLACE TYPE MYDATE AS OBJECT
2 (X INT
3 )
4 /

Type created.

SQL> drop type mydate;

Type dropped.

SQL> CREATE OR REPLACE TYPE DATE AS OBJECT
2 (X INT
3 )
4 /
CREATE OR REPLACE TYPE DATE AS OBJECT
*
ERROR at line 1:
ORA-02302: invalid or missing type name

SQL> CREATE OR REPLACE TYPE XMLTYPE AS OBJECT
2 (X INT
3 )
4 /

Type created.

SQL> show user
USER is “SYSTEM”

By: Alex Nuijten

Alex Nuijten — Wed, 20 Dec 2006 15:00:10 +0000

How very true and how very sad. Still there are lots of companies who use Designer and rely heavily upon it.
In September 2004, we had a session about the future of Designer. Here is the link to that session: http://technology.amis.nl/blog/?p=164

By: Michael Friedman

Michael Friedman — Wed, 20 Dec 2006 14:33:02 +0000

The real problem is that Oracle is not doing any further development with Designer.

Designer should support built in types and new data types like Intervals, etc.

It doesn’t.

As we move on to 11g and onward it will become less and less feasible to build systems using it.

By: Alex Nuijten

Alex Nuijten — Wed, 20 Dec 2006 09:41:26 +0000

@Nigel:
Unfortunately it is not possible in Designer to set a flag to prevent generation of Types, you can for packages, procedures and the like but not for Types.
I am having trouble to see your workaround though, how is it possible to define a column in a table which has the XMLType as it’s datatype?
Good point on revoking the CREATE TYPE privilege, too bad we need it for other Types.

@Marco
Do you ever sleep?
The XMLType that was created erroneously by the Designer Generator was the one I wanted to get rid of. Not the “real” XMLType which would destroy your XML DB…
Talking about reserved words, consider this:

SQL> declare
2 xmltype varchar2(10);
3 begin
4 xmltype := ‘Hello’;
5 dbms_output.put_line (xmltype);
6 end;
7 /
Hello

PL/SQL procedure successfully completed.

SQL> ed
Wrote file afiedt.buf

1 declare
2 date varchar2(10);
3 begin
4 date := ‘Hello’;
5 dbms_output.put_line (date);
6* end;
SQL> /
Hello

PL/SQL procedure successfully completed.

SQL>