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Avoiding the COMMIT bomb!

I’m an Oracle dinosaur, so I like using SQL Plus.  Its simple, fast, comes with every version and installation and platform, and I’m very familiar with it.  (And who knows, it might still be at the forefront of the Oracle development teams!  http://www.slideshare.net/hillbillyToad/sqlcl-overview-a-new-command-line-interface-for-oracle-database )

But there is one important thing I always take care of when I’m using SQL Plus, and it’s easiest to explain with an example.

You start off by wanting to delete a couple of rows from a critical table as part of a patching process.  You type this:

Oaktable World Las Vegas April 15, 2015 at Collaborate

oaktableworld_lasvegas1

 

Wednesday April 15 at Collaborate 2015 Las Vegas room Mandalay K
For more information see Pythian’s Blog post.

Screen Shot 2015-04-08 at 10.03.53 AM

 

(OT) an idea for Easter (and well…every day)

I don’t travel as frequently as some people do, but with OpenWorld and various Oracle conferences each year, I definitely see my fair share of the inside of a plane and a hotel room.  To pass the time on flights, I try to read, but when you’re reading on a work-based trip, it’s a case of reading a page or two here and there, rather than a true extended session of relaxed reading.

The net result ?  I generally buy what I call "airport crap" when it comes to books.  That is, cheap, easy to read, crime thrillers that are totally formulaic in nature.  Its pretty simple:

Edition based redefinition – an apology

In April 2008 (wow, does time fly!) I used the following picture in my "11g features for Developers" presentation at the Australian Oracle User Group conference.

image

I think the picture is from the movie "Indiana Jones and the Last Crusade"… where they sought the Holy Grail.

In-memory – can you REALLY drop those indexes ?

Its not a hard sell to convince anyone that a whopping huge great chunk of compressed column-based memory is going to assist with those analytic-style queries.  The In-memory option seems a natural fit, especially for those people where the bottleneck in their infrastructure is the capacity to consume data from storage.

What perhaps a more interesting area of investigation is the claim that In-memory will also be of benefit in OLTP systems, where (to paraphrase many presenters at OpenWorld 2014), we wont be needing all those indexes on transactional tables.

So I thought I’d have an initial play around in that space, and see what happens.

We’ll start with a simple test bed – a transactional table "T", being a child of parent table "PAR",  with a few indexes representing those "additional" OLTP indexes.

Try Oracle 12c VM with Delphix download


9104210308_a63b5ae5c4_z
 photo by #212124;" title="Go to Jose Maria Cuellar's photostream" href="https://www.flickr.com/photos/cuellar/" data-track="attributionNameClick" data-rapid_p="67">Jose Maria Cuellar (CC 2.0)

Thanks to Leighton Nelson who pointed out  that :

Oracle has a pre-installed Linux VM with 12c

Delphix as well has a pre-installed   trial version 

Try Oracle 12c VM with Delphix download


9104210308_a63b5ae5c4_z
 photo by #212124;" title="Go to Jose Maria Cuellar's photostream" href="https://www.flickr.com/photos/cuellar/" data-track="attributionNameClick" data-rapid_p="67">Jose Maria Cuellar (CC 2.0)

Thanks to Leighton Nelson who pointed out  that :

Oracle has a pre-installed Linux VM with 12c

Delphix as well has a pre-installed   trial version 

WHEN OTHERS … sometimes just not enough

We currently are working on a bug with Oracle Support with dbms_stats in 12.1.0.2.

That may be the subject of a latter post, but in a nutshell, here’s the issue

SQL> exec dbms_stats.gather_table_stats('MY_SCHEMA', 'MY_SCHEMA');
BEGIN dbms_stats.gather_table_stats('MY_SCHEMA', 'MY_SCHEMA'); END;
 
*
ERROR at line 1:
ORA-21700: object does not exist or is marked for delete

Now obviously that’s not meant to be happening, and it pertains to incremental stats on a database that’s been upgraded from 12.1.0.1 to 12.1.0.2.   More on that another time.

v$object_usage catches me out every time :-)

 

Every …. single …. time….

Why does index monitoring make me scratch my head and charge off to google so many times…Well, I’m over it, so time to put it on my blog (even though its already on many other places) so I do not get caught out anymore :-)

It always starts like this:

  • Turn on index monitoring on some indexes
  • Wait…
  • Come back later, and get ready to check on my results
  • Then this happens…
SQL> select * from v$object_usage;

no rows selected

And I panic…Did I run the commands on the wrong database ?  Did they not run properly ? Do I need to flush a pool ? etc etc etc

And after plenty of wasted minutes…I end up digging up the source for the v$object_usage view

Getting Psyched for Collaborate 2015

It’s that time again. Collaborate 2015 is fast approaching and, I have to say, I’m pretty damn psyched! This is the first time my personal company, NEXTGRES, will be demonstrating its game-changing database compatibility features to Oracle DBAs, developers, and users. I’d love for anyone reading my blog to drop by, whether it’s just to say “hi” or to see […]