Wanted New Speakers

Yesterday there was an email coming from the UK Oracle User Group (UKOUG) about their upcoming Tech conference at the end of the year.
There was a call to action to get more new speakers, but with a twist. This email wasn't directed at everybody, but specifically to people who have presented before at a UKOUG event.
Why would you sent an email to look for new speaker and only address the people that "have done it before"?
The call to action was basically: "reach out to new speaker by offering to do a joint presentation".

Why and How?

Now where did that idea come from?
A while ago I read a blog about the APEX Connect 2017 conference, it was posted anonymously and in German (Thank you Google Translate). Some parts of the blog were very positive, but there was also a critical note about the number of new speakers at the conference.
How the agenda was put together for the APEX Connect 2017 conference is up to the conference committee, there is only so much you can do about that - like providing feedback.
But that blog did get me thinking... I know that a lot of user groups really want to have new speakers, I also know that there are a lot of people out there that have a story to tell.
When I talk to people, at conferences, on the work-floor, anywhere and ask them about doing a presentation a lot of the same answers can be heard: "What I do is very simple" "I wouldn't know how to write an abstract" "I've got nothing to say" "so and so is an expert in that field, I've got nothing to add to it" "Nobody will show up" etc. etc. etc.
After a brainstorming session with Chris Saxon (while lunching at the RigaDevDays conference) and Jan Karremans (while waiting at the airport) I came up with the idea of a joint-presentation. Get a new speaker hooked up with a more experienced speaker and let the magic happen.
What will you get out of it as a first time speaker;

• You don't have to talk the whole slot, you only have to do half of the talk...
• Did you get a question that you don't know the answer to? There is someone else on stage that might know the answer.
• Get pointers for writing an abstract
• Get pointers for putting together a slide deck
• Get pointers for telling the story
• ...

The more experienced speaker can help with the above, and perhaps more.

Act now

Doing a joint presentation is a lot of work, it takes serious effort to put it all together. When you've done a presentation before you know this, and because of this I was pleasantly surprised to see so many speakers reaching out.
Alright, so if you've ever considered doing a (joint) presentation about SQL, PL/SQL and/or APEX - get in touch.

Invisible Not Null Column

Yesterday I attended John King (@royaltwit) session on Oracle 12c for developers. He gave an overview of all the goodies that are available to us as developers. The whole plugging and unplugging of database, though very cool and exiting, is most likely not very relevant to most developers.
When he discussed the possibility to have invisible columns in a table, it triggered the question: What happens when a NOT NULL column is made invisible? To see what would happen, I set up a small test case on my Oracle 12c database.

SQL> select banner
  2    from v$version
  3  /

BANNER
--------------------------------------------------
Oracle Database 12c Enterprise Edition Release 12.1.0.1.0 - 64bit Production
PL/SQL Release 12.1.0.1.0 - Production
CORE 12.1.0.1.0 Production
TNS for Linux: Version 12.1.0.1.0 - Production
NLSRTL Version 12.1.0.1.0 - Production

First create a table, two columns - both NOT NULL, and some data.

SQL> create table t
  2  (id   number not null
  3  ,text varchar2(10) not null
  4  )
  5  /

Table created.

SQL> insert into t values (1, 'Hello')
  2  /

1 row created.

SQL> insert into t values (2, 'World')
  2  /

1 row created.

SQL> commit;

Commit complete.

Next to change the TEXT column to be invisible.

SQL> alter table t modify (text invisible)
  2  /

Table altered.

SQL> desc t
 Name        Null?    Type
 ----------------------------------------- -------- ----------------------------
 ID        NOT NULL NUMBER

SQL> select * from t
  2  /

 ID
----------
  1
  2

The data that we entered is still there, or at least the ID values are still there.
So the column is now invisible, what if we try to add new data into it?

SQL> insert into t values (3)
  2  /
insert into t values (3)
*
ERROR at line 1:
ORA-01400: cannot insert NULL into ("SCOTT"."T"."TEXT")

Even though you can't see the column, the NOT NULL constraint is still enforced.
When you name the column explicitly, you can still do DML on it.

SQL> update t 
  2  set text = upper(text)
  3  /

2 rows updated.

But not like this

SQL> insert into t values (3, 'Goodbye');
insert into t values (3, 'Goodbye')
            *
ERROR at line 1:
ORA-00913: too many values

This following is still valid, and again shows that naming the columns in an INSERT statement is a good practice.

SQL> insert into t (id, text) values (3, 'Goodbye');

1 row created.

Looking back at UKOUG 2011

Now that the UKOUG annual conference in Birmingham is over, it's time to write my thoughts down. As this was the second time that I attended the UKOUG conference, I already knew that it is a big conference. Lots of great speakers and a very good agenda. On the agenda were very interesting session, sometimes making it very hard to choose which session to go to. Guess you can't complain about that.

My First UKOUG - day two and three

Why can I never find the time to write my blogs?... Anyway, long overdue, here is my report from my first UKOUG conference. If you want to know what I did the first day, check out this link.
As I mentioned before the program is awesome, lots of very good speakers and very interesting subjects. It's quite hard to pick and choose the sessions. So what did I do the second and third day there?

My First UKOUG - day one

Last week the UKOUG-TEBS conference was in Birmingham. For whatever reason I had the idea that this conference was fairly small - no idea why I thought that.
The conference was held in the ICC in Birmingham, a wonderful location.