The Django Fandango Farrago – Looking at Django’s Physical Data Model Design

I’m sure I’m not the only Oracle Developer who, over the years, has conjured a similar mental image during a planning meeting for a new web-based application…

wibble

…and we’re going to use an ORM

If you want the full gory details as to why this is so troubling from an Oracle database perspective, it is a topic I have covered at length previously.

This time, however, things are different.
Yes, I am somewhat limited in my choice of database due to the hardware my application will run on (Raspberry Pi).
Yes, Django is a logical choice for a framework as I’m developing in Python.
But, here’s the thing, I plan to do a bit of an audit of the database code that Django spits out.
< obligatory-Monty-Python-reference >That’s right Django, No-one expects the Spanish Inquisition ! < obligatory-Monty-Python-reference / >

torturer

Donde esta el Base de datos ?!

I know, this is a character from Blackadder and not Monty Python, but I’ve often regretted the fact that there never seems to be a vat of warm marmalade around (or some kind of gardening implement for that matter), when you enter those all important application architecture discussions at the start of a project.

As a result, one or two further Blackadder references may have crept in to the remainder of this post…

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Configuring Django with Apache on a Raspberry Pi

Deb has another job for me to do around the house.
She would like to have a means of looking up which Films/TV Series we have lying around on Blu-Ray or DVD so she can save time looking for films we haven’t actually got. Just to be clear, she doesn’t mind hunting around for the disc in question, she just wants to make sure that it’s somewhere to be found in the first place.
She wants to be able to do this on any device at any time (let’s face it, there’s even a browser on your telly these days).
As DIY jobs go, this is a long way from being the worst as far as I’m concerned. After all, this time I should be able to put something together without the potential for carnage that’s usually attendant when I reach for the toolbox.

I happen to have a Raspberry Pi lying around which should serve as the perfect hardware platform for this sort of low traffic, low data-volume application.
The Pi is running Raspbian Jessie.
Therefore, Python is the obvious choice of programming language to use. By extension therefore, Django appears to be a rather appropriate framework.
In order to store the details of each movie we have, we’ll need a database. Django uses with Sqlite as the default.

We’ll also need an HTTP server. Whilst Django has it’s own built-in “development” server for playing around with, the favoured production http server appears to be Apache.

Now, getting Django and Apache to talk to each other seems to get a bit fiddly in places so what follows is a description of the steps I took to get this working…leaving out all the bits where I hammered my thumb…

Breaking the Rules – why sometimes it’s OK to have a standalone PL/SQL Function

It was late. We were snuggled up on the sofa, watching a Romcom and debating whether to go to bed or see it through to the bitter( well, sickly sweet) end.

Wearily, I made the point that in the end the film would follow Heigl’s Iron Law of Romcom which can be summarised as “Katherine always gets her man”.

Deb begged to differ. Her argument was that, for every Colin Firth, riding into the sunset with his Bridget Jones, there’s a poor( largely blameless) Patrick Dempsey whose immediate future includes long-evenings alone in front of the telly and shopping for microwave meals for one.
The point is that even the most rigid rules tend to have their exceptions.

The star of this post is the oft-quoted rule that PL/SQL program units should always be incorporated into a Package.
There are special cameo appearances by “Never use Public Synonyms” and the ever popular “Never grant privileges to Public”.

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Automated Testing Frameworks and General Rule-Breaking in PL/SQL

If there’s one thing that 2016 has taught us is that rules (and in some cases, rulers) are made for breaking. Oh, and that it’s worth putting a fiver on when you see odds of 5000-1 on Leicester winning the League.

Having lacked the foresight to benefit from that last lesson, I’ve spent several months looking at Unit Testing frameworks for PL/SQL. In the course of this odyssey I’ve covered:

This post is a summary of what I’ve learned from this exercise, starting with the fact that many of the rules we follow about good programming practice are wrong…
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Post-Truth PL/SQL

We’re living in a Post-truth age. I know this because I read it in my Fake News Feed.
Taking advantage of this, I’ve updated the definition of PL/SQL.
Up until now, it would be true to say that PL/SQL is a 3GL based on ADA that’s incorporated into the Oracle RDBMS.
Post truth, the definition is that PL/SQL is a 3GL that comes with it’s own built-in Oracle RDBMS.

By a stroke of good fortune, my son recently bought me a copy of Ghost in the Wires by Kevin Mitnick and William L Simon, which begins each chapter with an encrypted phrase.
If your anything like me, you’d spend a fair amount of time geeking over this sort of problem, most likely using some fashionable programming language to help solve the riddles with which you were presented.

In my house at least, PL/SQL is back in fashion…
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Testing Times – using ruby-plsql-spec for testing PL/SQL

There is method in the madness. It’s now clear that Donald Trump’s reluctance to commit to the Paris Climate Change Accord is because US methane emissions have been hugely under estimated. Yes, it turns out that there are many more Shy Trumpers in America than (almost) anyone expected.
Meanwhile, back in the UK we know that Brexit means Brexit but we still don’t know what Brexit means.
In amongst the chaos, UKIP have decided to take a fresh approach to the business of selecting a leader. This time, they’re staging a Cage Match.

Taking a leaf out of UKIP’s book I’ve decided to take a slightly unusual approach to Unit Testing my PL/SQL code.
Having looked at the SQLDeveloper Unit Testing Tool and utPLSQL, both of which utilise the database to persist objects, this time, I’m taking a look at a framework which takes a rather less database-centric approach, namely ruby-plsql-spec.

What I’ll be looking at is :

  • Installation of the framework and required components
  • A quick recap of the application being tested
  • Writing and executing Unit Tests
  • Summary and conclusions

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Chasing your tail – with SQL*Plus and SQLcl

Do you remember the film Up where the dogs were always distracted as soon as anyone mentioned squirrels ?
Well, there I was, continuing my journey through the wonderful world of PL/SQL Unit Tests when suddenly, SQLcl !
Yes, Oracle have just released the first production version of SQLcl.
Since I first looked at an Early Adopter version of SQLcl there have been several enhancements. One of these, the REPEAT command, has the potential to implement functionality akin to the good old *nix tail -f command for Oracle Database tables.
It turns out that you may also be able to do something similar in SQL*Plus…
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