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Delphix Express – a free version of Delphix


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#555555; text-align: right;">photo by #212124;" title="Go to Yannis's photostream" href="" data-track="attributionNameClick" data-rapid_p="48">Yannis (CC 2.0)

Continuous Delivery – Moving to SECUREFILE

You’ve been google-ing and you’ve seen articles (for example) like and you’re pretty pumped about using SECUREFILE features.  You’ve got lots of existing CLOB data and moving to SECUREFILE is going to make your life much easier.  You’re also excited about the fact that none of your code has to change – you just change the existing CLOB columns to be stored as SECUREFILE and you’ll have set yourself up for all sorts of feature goodness !

But how do we do it in a continuous delivery (CD) model ?  Because moving CLOB’s sounds like downtime doesn’t it ?

And by default, that’s exactly what it will be.  Let’s explore that with a faux application that uses CLOB’s.

Continuous delivery…

“Continuous Delivery (CD) is a software engineering approach in which teams keep producing valuable software in short cycles and ensure that the software can be reliably released at any time”


Perhaps a simpler definition is “CD is the currently the cool thing to do” Smile

Sarcasm aside, there’s a lot of common sense in being able to rapidly push out software changes in a safe manner. 

Partial uniqueness

I had an interesting request recently from a developer.

“ I have a table created as per below

create table C_TEST (
  col_1 varchar2(3),
  col_2 varchar2(3),
  col_3 number

The rows defined by col_1, col_2, col_3 must be unique but only when col_3 is present.  If col_3 is not present, then we allow anything.  Hence if the table is populated like this:

Oracle Developer awards…chosen by Developers

I was reading the following post today

Oracle are planning on rewarding developers in the following areas:

  • SQL
  • PL/SQL
  • Oracle REST Data Services
  • Oracle Application Express
  • Database Design


At first glance I had a bit of a cynical view…it could easily be one of those things where if you come from a company that has massive investment in Oracle, then surprise surprise you float to the top of the heap. 

But this part of the post caught my eye:

The technology community

I remember on a flight to the UKOUG, I was doing what all presenters typically do on a plane.  They enter the cabin with the thought of "OK, I’ll spend most of the flight getting those slides just right".  Then…a set of broadcast advertisements, safety messages, hot face towels, exit row briefings, beverage services, coffee services, and before you know it you’ve burned 2 hours without touching the laptop…and then the meal service starts :-)

Anyway, I digress.  I eventually got the laptop fired up and started flicking through my slides for the 800th time – I suffer from that silliness where if I’m thinking "Hmmm, if replace with ‘database’ with ’12c database’", then this somehow will make a significant improvement for the attendees.  After a while the laptop gives me a little ‘beep’ telling me that battery is low.

Good new SQL tuning book

People ask me from time to time what are some good SQL tuning books. It’s a tough question to answer. There are some seminal books such as “SQL Tuning” by Dan Tow and “Cost Based Optimizer Fundamentals” by Jonathan Lewis, but these are advanced books  that few I know have actually read from cover to cover. If you are looking for practical SQL tuning cookbooks you might want something a little less advanced.  For a practical approach, I love “Refactoring SQL Applications” by #111111;"> Stephane Faroult which is an easy read, again, it’s not a straight forward SQL tuning book.

Upgraded and can’t see the tables you could before ?

If you take a look at the "alter user" command in the old 9i documentation, you’ll see this:


Specify the roles granted by default to the user at logon. This clause can contain only roles that have been granted directly to the user with a GRANT statement. You cannot use the DEFAULT ROLE clause to enable:

  • Roles not granted to the user
  • Roles granted through other roles
  • Roles managed by an external service (such as the operating system), or by the Oracle Internet Directory

Oracle enables default roles at logon without requiring the user to specify their passwords.

You never stop learning

My mate Scott Wesley, whose specialty is Apex, is currently at Kscope having the time of his life (well, I hope so Smile).  He tweeted this picture last night of his conference badge, mainly about the “I love Apex” buttons, but something else struck me.



Open Source is Free – Free like a puppy!

I’m at the ODTUG Kscope conference in Hollywood Florida and was just talking with some Oracle folks about Open Source (yes, Oracle has people devoted to working with Open Source tools) and I shared with them my general comments to students and colleagues about Open Source.

There are two kinds of free:

1. Here’s a free cup of coffee (or beer or soda…)

2. Here’s a free puppy

When accepting option 1 (free coffee) you take it, consume it, and enjoy.

When accepting option 2 (free puppy) you take it, you find a place for it to sleep, you take it to the vet, you walk the puppy, you feed the puppy, and oh-yeah — every once in a while the puppy might make a mess on your floor! You’ve made a commitment.
(I cannot take credit for the metaphor; I first heard it used by friend and colleague Jim Cody of Cardinal Directions – thanks Jim!)

Clearly, “free” is not always “completely free”