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“Oracle Indexing Internals & Best Practices” Seminar: Australia 2017 Tour (Stage)

Richard Foote's Blog - Mon, 09/18/2017 - 22:10
I’ll be running a fully revised and updated version of my acclaimed “Oracle Indexing Internals and Best Practices” seminar throughout Australia in Oct/Nov 2017. Previous versions of this seminar have been hugely popular and run in some 18 countries. This updated version will feature lots of new material including 12c related indexing capabilities and recommendations. […]

Richard Foote Consulting Has Arrived (New Angels Of Promise)

Richard Foote's Blog - Sun, 09/17/2017 - 22:32
Today is the official launch of Richard Foote Consulting, my new independent company in which I’ll be providing specialist Oracle Database consulting and training services, focusing on database performance tuning, database problem resolutions and database health check assessments (at least until everyone moves across to the new self-tuning Oracle Cloud database). Based on all the […]

Adding the game, the importance of the APEX Advisor, a lot of JavaScript and adapting for mobile

Dimitri Gielis Blog - Wed, 09/06/2017 - 18:48
This post is part of a series of posts: From idea to app or how I do an Oracle APEX project anno 2017

Over a year ago I developed the game to practice the multiplications. I quickly created an Oracle APEX page, added a bunch of JavaScript and that was about it. The last weeks you could read I've redeveloped the entire app from the ground up but I still have to add the game to it.

I thought to just copy the page I developed before with all the JavaScript in the new app.

How do you copy a page from one Oracle APEX environment to another? 

Export the app from the first environment and import the app in the second environment. Once both apps are in the same workspace, you can copy a page from another app by going to the Create button:

Click the Page as Copy option and follow the wizard:

So I followed the wizard to copy the page to my new app.

Now the tricky bit was that I changed page numbers, so all my references (in JavaScript, Processes etc.) to page items were wrong. To quickly identify the issues I used the APEX Advisor.

The APEX Advisor you find in App Builder > Utilities : Advisor

The Advisor checks for best practices, errors, security issues etc. I really like the Advisor as it will give your application some kind of quality control. And it's very fast to identify issues and navigate to them. Here's a screenshot what the Advisor found:

I would always run the APEX Advisor, even when you start from a Blueprint application as you will most likely modify the app, add pages, make changes etc. and it's easy to forget for example to put an authorization scheme.

A few years ago I also wrote an extension to the APEX Advisor that would check for our own standards. You can query an Oracle APEX application with SQL, so it's easy to check if naming conventions where followed, if deployments went fine or anything else you find important. Here's a screenshot of some of the checks in one of the projects:

In the community some other people did something similar, for example Oliver Lemm wrote a Quality Assurance plugin.

So back to my application - I fixed those issues and was able to play the game :)
(screenshot from the browser)

To build the table/grid of the game I programmatically generate the APEX items by using the API apex_item.

All the rest is build in JavaScript. I'm not going to put all the source code in this blog post, but if you right click on the page where the game is, and you look at the source, you see all the JavaScript that is used.

Whenever the Start button is clicked, a Dynamic Action is fired which calls some other JavaScript functions. The fireworks and stopwatch are libraries I found on the internet which I integrated in the APEX app. If you have any question on the JavaScript side, feel free to ask in the comments section.

A few weeks ago I released the app to test. Some people sent me an email with their feedback, but many also used the build-in feedback mechanism that came with our Blueprint app.

I typically leave a feedback mechanism in every app I build (yes, even in production), it's a great way to communicate with your users.

The result of the feedback was, it didn't run great yet on mobile devices. Except from using Universal Theme, I didn't really pay attention to mobile devices, as I thought it would be too small anyway, but apparently people were trying it on there. So I decided to make sure it would work on at least a tablet, for example I saw a use case for myself to let my son play on my iPad.

In the next section I will go in a bit of detail of things that I had to adapt to make it more user friendly on a mobile device and some other things that might be interesting to know in other applications.

So here's how the app looks like on an iPad:

Compare this image with the image before taking in the browser and you will see some differences.

I added some JavaScript library to check if we run on a mobile device and when so, we add some extra CSS to make the table fit on the screen. The breadcrumb will always be shrunk and the padding is less. Here's the code:

When starting the game the keyboard comes out. One of the first things I had to do, was to make the number keyboard the default and not the normal keyboard with the letters. The way you do that is in your input text item, you define a pattern and give it a type of numeric (see the PL/SQL code where we do the call to apex_item).

The keyboard that slides out hides a part of the table, so it's not ideal. I've an external keyboard for my iPad, so hooking that up, makes it a really nice experience:

Another issue on the iDevice was that the fireworks at the end of the game didn't work well. So I decided to add a setting, so you can choose what you want to see at the end when you finish the game and when you run on an iDevice, the Fireworks is hidden.

The other settings are based on feedback. Some people don't want to play all numbers yet, so you can now pick the numbers. Some others wanted to see the time or countdown, and for some others they got stressed by it. So I decided to make it customizable per player.

Those preferences are all normal APEX items, but the difference is the way they get stored. I only use one field (preferences column in the mtl_player table) to store all preferences. The way I do that was inspired by the APEX Multi-language translate plugin (JTL Item) from my friend Jorge Rimblas, who stored all translations in one field by using JSON. So, all the settings of the game are stored in one JSON object.

On page load I use following JavaScript to set the items:

There's also a save button in the settings section. There's a straight forward dynamic action to do the update. But once saved I show a notification which is done by adding a call to the APEX JavaScript API:

apex.message.showPageSuccess("Player settings saved.")

This results in:

While you play the game on every switch of the number, the timing is saved by calling an AJAX Callback process by apex.server.process (see the source on the page when you play the game). For now I've done it this way, but maybe in the future I might cache the results and only do a callback at the end.

The last thing I want to cover is the overlay you get when you end the game. You have the fireworks, an image or a message as on the below screenshot.

The overlay is done by adding a div on the page and some CSS.

By default it has display set to none, but once the game is complete it's set by some JavaScript.

Hopefully this gives you more insight how the game was created and some things I cover are also useful in your own project.

If you want to play the game, surf to http://mtable.online.

Happy playing!

Presenting at UKOUG Tech17 Conference in December (Here Come The Warm Jets)

Richard Foote's Blog - Wed, 08/30/2017 - 00:39
I presented at the UKOUG Tech14 conference in Liverpool and thoroughly enjoyed the experience. It was one of the better User Group conferences I’ve attended and winning both the Best New Oracle Speaker and Best Oracle Speaker awards made that bit more special. So it’s with real excitement that I have the opportunity to again […]

Create a Custom Authentication and Authorization Scheme in Oracle APEX

Dimitri Gielis Blog - Tue, 08/29/2017 - 20:09
This post is part of a series of posts: From idea to app or how I do an Oracle APEX project anno 2017

Before when creating the APEX application based on a Blueprint, we used the standard APEX Authentication, which means the management of users is done in Oracle Application Express itself. As we created our own user table, we want to manage our users there and have some custom authentication scheme for our multiplication application.

In this post I will show you exactly how I built the custom authentication scheme for my Oracle APEX application you see at mtable.online.

I first decided which kind of login page I wanted. A few years ago I blogged about pimping the logging page, which is what I use on the APEX Office Print login page. This type of page is a more traditional way of building a login page in Oracle APEX. For the registration page and forgot password page we used the same techniques.

For the multiplication table project I decided to do it a bit different. I started from the landing page and build the login mechanism into that page. But also the register and forgot password are on the same page, so not like what we did for APEX Office Print, using different pages for forgot password, register and login.

Here's how my page looks like in the Oracle APEX App Builder:

There are a few regions to help with the layout (Top, Left, Right). In the Right region, there are 3 sub-regions: Login, Register, Forgot Password, which will show one at a time. Dynamic Actions (Show/Hide) control which region is seen.

From the front-end this is what it looks like.
When clicking a button an APEX process is being fired, but all the logic is defined in a package.
The package to handle the authentication I typically call [project trigram]_AUTH_PKG. It doesn't only contain the authentication logic, but also the registration, reset password and authorization logic.

The specifications looks like this:

.gist .blob-wrapper.data { max-height:600px; overflow:auto; } And the body like this:

I typically use dbms_crypto to generate (hash) the passwords, but as that package is not supported on Oracle Exadata Express at the time of writing, I use another SHA256 PL/SQL implementation.

I'm not going into too much detail on the logic in the PL/SQL package. I hope it's kinda self explanatory, but if you have any question, feel free to ask in the comments field.

Now we will focus on creating a Custom Authentication Scheme in APEX.

Go to App Builder > Shared Components > Authentication Schemes and hit the Create button to add a new one:

Enter the custom_authenticate procedure from the package we created earlier:

By default the new authentication scheme will be current, so make sure you have some data in your tables, otherwise you won't be able to login.

Next I typically add some post authentication to fill some Application Items.
Edit the Custom Authentication and add the code and post_auth as in this picture:

We have now made our application accessible to people by defining our own custom authentication scheme.

Next, we want to define which rights you have in the application. To do this, we will create two Authorization Schemes, one for a normal user and one for an administrator.

In our package we already included a function with the logic. Every user has a role defined to him, and depending the role, it's a normal user or an administrator. An administrator can do everything a normal user can do, but can also access the administrator section where we maintain our application.

Blueprint actually already created our Authorization scheme for administrators, but we will adapt it to use our package. Go to Shared Components > Authorization Schemes and modify like this:

I hope it gives you all the components to build your own custom authentication and authorization schemes.

I also recorded a video which goes in more detail on the entire process of signing up, forgetting password and logging in and the different authorization schemes and code being used.

Build the Oracle APEX application: the framework

Dimitri Gielis Blog - Sat, 08/19/2017 - 06:33
Over the years while developing Oracle APEX application, I noticed in every application I was following the same steps. It was a routine I followed over and over. For example: in every application I created a global page (page 0), enabled Feedback, ran the Advisor multiple times a week, used certain naming conventions etc.

A few years ago I wrote those steps in our APEX R&D development guide, so within our team we would be consistent. Just like the database best practices, I thought it would be a good idea to share the APEX best practices with you as well. There are about 9 pages, here's a screenshot of the first page:
I don't like too many rules, but a few are good to have, especially when you get new people on board or when the customer is working together with you. As I said in my previous post where I described our database guidelines, the guidelines in itself is not meant to be "this is best and you have to follow", it's more something to start from which you can adapt.

Based on those guidelines, we created a "starter application", so you get a head start in your project. The app in itself wasn't spectacular in itself, it contained the global page, feedback, some administrator pages which give statistics of your app, some application items, error handling package etc.

If you know what you have to build, it wouldn't even take that long to build it from scratch. I just don't like to do repetitive things, I far rather concentrate on the real solution, so anything that can help, I will embrace :) I also won't hesitate to take some components or solutions from other projects and reuse those. But just one piece of advice, always check if what you've been doing before, is still valid today and "the best" way of doing it -for your current problem-. For example if you developed something in APEX 4.2, maybe in APEX 5.x there's a build-in package to do that. Or the other way, that a feature of APEX became deprecated (e.g. apex_plsql_job) and you should use a database feature (dbms_scheduler).

In 2015 I also gave a presentation at some Oracle conferences how I developed in APEX 4.2 vs 5.0, which you find here.

So I could use my starter app for this project, but just as with Quick SQL (to create your database objects), there's a new feature in Oracle APEX 5.2 that will make the starter app irrelevant, so I will cover the new way of doing something in 2017 and further.

The new way of building an application, is to start from a "Blueprint". The concept is very similar to my workflow previously, but now it's built-in the APEX Builder and it's more powerful as it allows to customize the features you want to include in your app.

Blueprint is at the time of writing only available in Preview mode (since March 2017) through apex.oracle.com and will probably undergo some more changes. I see a lot of potential in this feature. It's not only the wizard you can use, rumors are you can also use JSON syntax to define your app.

Here's the video I recorded where I give a bit of background and you see me using Blueprint:

At the time of writing Blueprint isn't finished yet. Not sure what the end result will be, but although there's still a lot of room for improvement, it already looks spectacular. As you could see in the video, I will use it as my starting point for my multiplication table project. I've exported the app of apex.oracle.com and imported in my Oracle Exadata Express environment. Next I'll make changes to this app and customize further.

Blueprint is (or will become) the fastest and most low code way to build an Oracle APEX application.

Update August 19th: on apex.oracle.com a new version of Blueprint is available with even more options than you see in the video.

Set up domain and launch page

Dimitri Gielis Blog - Mon, 08/14/2017 - 20:56
This post is part of a series of posts: From idea to app or how I do an Oracle APEX project anno 2017
Domain nameWhen you launch an app or service, you probably want a domain name. I register all my domain names with Godaddy. I'm a long time customer with them and I find them really reliable, not that expensive and they have good support. But I find it hard to come up with "the right" domain name. For example for our project I wrote on a piece of paper all different domain names: multiplicationtable.com, multiplicationstable.com, multiplications.edu, multiplicationtable.online, multiplicationtable.guru etc.

What domain would be perfect for our application? At one side you have to think about Google, a descriptive domain helps in your ranking, but on the other hand you want it to be easy to type and remember. Finally I decided to register mtable.online as my first choice multiplicationtable.com was taken. If you know a better domain that is still available, feel free to add in the comments field :)
Link domain name to Oracle APEX appOnce you have the domain name you want to link it to your Oracle APEX application.

In a future post I will cover Reverse Proxy and SSL, but for now, as I want you to see what is happening, I just configured in Godaddy to redirect to my Oracle Exadata Express url.

I don't want to let the world wait to know about our project, so I want to setup a landing or launch page. This page serves as a home while we are building our application. People can already register, so once we are live, we can let them know about it.
How do you build a landing or launch pageEither you have an idea about how you want the page to look like, or what I do as well, is look at other sites or templates created by others. For example for the APEX Office Print website we bought a template as starting point and integrated it in our APEX app.

I get often inspiration from following sites:
If you know some graphic design people, they can obviously help too :) It's easy(ier) to recognize good design, but it's hard(er) to create it yourself.

I like minimalist design or "less is more". If you look at the multiplication table project launch page, only the bare minimum is on the page: a title, a graphic, a text item to leave your email and a button (and a text to let everybody know it was built with Oracle APEX.

You find some more examples of minimalism here or just Google for it and you find plenty. Typically you will see a background picture and a text. If you find a template you like, you can look at the HTML and CSS and copy this in your own APEX page.

The font you use is really important and can make a huge difference. Google Fonts are a good starting place to pick a font. In our project I used the Raleway font.

In the last month (that I know) two other people showed how to build a landing page in APEX: Stefanie used a background picture and Richard used a video as background.
How long to build a landing pageWhen I look again at our launch page, I would probably tell you it would take me less than 30 minutes to build it in Oracle APEX. If you know what you will build, yes, but if I told you it took me well over 6 hours to build this landing page, would you believe me? It's the truth!

So where did I spend all my time then?

I first started to search for a design. I didn't really want to copy something from a previous project, but rather wanted to get a fresh new design, so I started to search, and search and search more. Finally I gave up on the idea and followed my own thoughts to do it very minimal and as close as possible to universal theme that comes with APEX.

So I added the regions, items and a button on the page:

This goes fast (if you know a bit of APEX). As I wanted the image on the left of the items and the items going down a bit, I used two regions next to each other.

I looked at the result and didn't like it, so I added some CSS and searched for another font. This was a lot of trial and error till I was happy with the result.

Once that was done, I looked how responsive it was. On a smaller screen, I didn't find it looked good enough, so I added a media query and custom CSS, so it would look better.

Oh, before I forget, whenever you build an app in Oracle APEX, include the plugin built with love using Oracle APEX.

Next up, I had to include a validation (to check if the email already exists), a process and a branch. Now here's a story too... I first started with adding a dynamic action on the Subscription button that would insert a record, but during testing I found I lost the value required and is email validation that you get for free when you submit your page, so I changed it to be a normal process.

Finally I changed on the page that duplicate submissions are not allowed.

So the end result is we have one very simple page in APEX, using standard components (regions, items, button), 1 plugin (built with APEX), Universal Theme and a bit of custom CSS.

Goodbye Oracle Corporation (Modern Love)

Richard Foote's Blog - Mon, 08/14/2017 - 07:39
  It’s with a mixture of excitement, trepidation and a touch of sorrow that I today handed in my resignation after 6 years at Oracle Corporation. My plans at this stage are to take a bit of time-off initially, before going back to providing Oracle Database consulting and training services as I’ve done in the […]

Create the Oracle database objects

Dimitri Gielis Blog - Sat, 08/12/2017 - 18:49
This post is part of a series of posts: From idea to app or how I do an Oracle APEX project anno 2017

In a previous post we defined the ERD of the multiplication table application we're going to build. Now I want to go into detail how I create the Oracle database objects like tables, foreign keys, sequences, triggers, etc.

Before I tell you what I do today, let me first walk you through my history so you understand why I'm using it.
Data Modeling ToolsData Modeling Tools allow you to visually create your tables, relationships, etc. If you work with Oracle for 10 or more years, you probably know Oracle Designer. This tool has been really popular, but today it's legacy and not maintained anymore by Oracle. Oracle moved forward with SQL Developer Data Modeler. Although I've been using those tools in the beginning, today I typically don't use them anymore, except for generating a visual diagram (ERD) of my tables, but that is now part of SQL Developer, so I don't have a data modeling tool installed anymore. The main reason for me was, it took me so much time to add the entities, that it was too slow for my process. As written earlier, I typically draw my entities on a whiteboard or piece of paper, after that I want to get going with real tables and data as fast as I can to verify the model.

If you have a big team and somebody is solely responsibility for modeling, I see a benefit of using a modeling tool or if you like the process of visually creating a model. There're probably more advantages using a modeling tool, so if you use it and like it, don't change because of this blog post, I just share how I typically do a project.
ManualSo if I didn't use a modeling tool, what did I do? I created the tables manually. I hear you think, yeah right, and that is faster? It was for me, because I had a certain workflow. I used strict naming conventions: 3 letters for the project, singular table names, meaningless id column in every table etc. Here's an overview screen:

You find the complete guide of my naming conventions here.
Those naming conventions were the base, but per project or customer we could adapt to their standards. The principle was that I created tables with only the relevant columns, a meaningful unique key and a comment.

Next I used a script that would generate all the primary keys and foreign key relationships, sequences, triggers, audit columns and everything else that I could automate for the particular project. You find the base of the script I used till two years ago here and a screenshot of a part of the script:

The only reason I could do this, was because I used strict naming conventions e.g. table_id column (fk) would be a reference to the id column of a table (pk). By doing this, I could really iterate fast on creating and adapting tables, it worked great for me.
The final step was to create a visual ERD of it in SQL Developer (or other tool) as it was easier to communicate with the team and we always include it as part of the documentation.

As I'm writing in the past, you probably figured that I stopped using this method. The reason is simple, because there came something I like even more :)

But before we move on, a final word on naming conventions; it's not which naming conventions you use that is important, it's more about being consistent within your project and make it easier for you to understand your model and have faster knowledge transfer. So whatever naming conventions you use is fine, there's not something like "this is the best" in my view.
Quick SQLSo now we come to today... this little tool is what I use to create a script for my database objects.

I can't explain Quick SQL better than what you find on the site:

Quick SQL enables you to rapidly design and prototype data models using a markdown-like shorthand syntax that expands to standards-based Oracle SQL. You can easily create master detail relationships, check constraints, and even generate sample data.
Quick SQL is a packaged app which comes with Oracle APEX, so you have it, without knowing :)

So back to our multiplication project; the first thing I did was installing the packaged app in our APEX workspace. Go to App Builder > Create > Packaged App > Quick SQL. Next run the app and this is the screen you will see:

Next you start typing your tables and columns and some additional syntax to specify constraints etc. The power of Quick SQL is that it not only generates the tables, but it has built-in naming conventions, generates indexes, constraints, triggers, views and even sample data.

Here's a video of me creating the script for our multiplication table project:

The next thing I do is generate with SQL Developer the ERD, so I visually see it. Just follow the wizard in SQL Developer you find in File - Data Modeler - Import - Data Dictionary:

While reviewing the visual ERD, I saw I made a small mistake in Quick SQL. I didn't specify timezone with local timestamp (tswltz), but just timezone with timestamp (tstz). In the application for my son I used a date for that column, that is why I called that column start_date and end_date, but the more logical name is start_time and end_time, so I changed that too. I want to use timestamp with local timezone as this app is probably going to be used around the world, so it would be nice if you could see the time you actually played in your own timezone.

Here's the final version of the script in Quick SQL:

It's very easy to make changes in Quick SQL, and in settings I just included the drop statements and re-ran the entire script in SQL Dev and I was done :)

I really like Quick SQL and I hope it gets even more improved in the future. It would be really nice to version control the scripts and be able to generate the differences for the tables (alter statements instead of create statements) or do reverse engineering of a specific schema. Another improvement I hope to see in the future, is the ability to define unique constraints on multiple columns (or it might be already there, but that I don't know how to use it?).

The visual ERD is below:

In this post we went from the paper ERD to real Oracle objects. Now we are ready to build our app.

Set up an APEX development environment

Dimitri Gielis Blog - Thu, 08/10/2017 - 18:51
This post is part of a series of posts: From idea to app or how I do an Oracle APEX project anno 2017

A development environment can mean different things to different people. You can read the definitions on Wikipedia, TechTarget, Techopedia to name a few.

For me, it means on one side you need an environment where you can develop in. In case of an Oracle APEX project this means, you need at least an Oracle schema and an APEX workspace linked to the Oracle schema in which you can create your APEX application. Now if we take this a step further, it means you need an Oracle Database and APEX installed, which includes a webserver and ORDS (Oracle REST Data Services). And again one level higher it means you need a machine (that is most likely connected to the internet).

On the other side you have everything around it: some tools you use, something to plan and track the development, something to store your code (version control), something where you can collaborate with other team members. If we include this we talk more about software development in general which touches on application life cycle management (moving to Test, QA, Production).

Lets first focus om the first part; the infrastructure. Unless we get millions of concurrent users, I don't think our multiplication table project needs much infrastructure :)

I will walk over the different options we have when doing an APEX project.
On-premiseYou basically have your own machines and installed all software on there and you manage everything yourself. Many of my customers still have an on-premise infrastructure. Unless you see our laptops as on-premise, at my own company we never had on-premise, we've always been in the cloud. While running in the cloud you still have different options of the level of responsibility and flexibility you have yourself. We use cloud services from Amazon, Microsoft Azure, Digital Ocean and the Oracle Cloud. More on that further on.
apex.oracle.comThis is the fastest way to get started, we just sign up for an account on apex.oracle.com and get an APEX workspace and underlying Oracle schema. Apex.oracle.com also contains the latest version of Oracle Application Express (APEX) as the development team uses this service to roll-out and test new features and versions first. If you don't have an account yet, I recommend to create one. I've requested a workspace for this project too (takes less than 2 minutes), which you can see here:

Now we can use this service to develop and test, but we can't keep our application here forever, as we only have 25MB of space and you're not supposed to run production applications here. It's also not possible to connect to this service from SQL Developer or other tools, so it's a bit limiting. But in a future post "Build the Oracle APEX application: the framework" you will see why I still setup this workspace and I recommend everybody to have at least one workspace on apex.oracle.com :)
Oracle pre-built Developer VMAnother fast way of being up and running is to download the Oracle pre-built Developer VM for Virtual Box. Everything is already setup for us, but we would need to put it somewhere on a server where it can be accessible through the internet by more people. I typically don't use this solution to do my development, only to test something locally.
Free Oracle Database Cloud ServiceThis service from Oracle has been announced a few months ago, but is not yet available at the time of writing. The rumours are you get 1GB of data, have APEX 5.1 or higher, you're running in the Oracle Cloud and can run production applications there. This solution would have been ideal for our multiplication table project!
Cloud with OXARIf you're searching to build a low cost infrastructure based on Oracle XE (the free Oracle database), you really should use one of OraOpenSource projects, called OXAR (read "Oscar"). It sets up an entire machine by itself, it's completely scripted. The only thing you have to do is download the Oracle software (XE, ORDS, APEX), get a low cost virtual machine (for example at Digital Ocean or Amazon), clone the OXAR git repository on that machine, edit the config file to point to the downloaded files and run the build.sh script. That is it! Even the most popular print engine for Oracle APEX, APEX Office Print (AOP), comes installed with it :)

The biggest benefit of an Oracle XE infrastructure, it's a very cheap solution, the downside is that Oracle XE is still Oracle DB 11g with many restrictions, so we can't use some 12c features (like JSON in DB, ...). Rumours are there will be an Oracle XE 12c version coming out in the future. Maybe even more important to know; there's no Oracle support for this database. Although at first sight you might not need it, it also implies you can't download Oracle APEX patches, as you don't have a CSI number. If you have a CSI number for another infrastructure and downloaded the APEX patches, you can obviously patch your APEX in Oracle XE. If not you would need to download and reinstall the full version of APEX every time, which becomes time consuming.

So lets look at our multiplication table project, we can definitely use OXAR for this as it fits within the XE limits. I subscribed at Digital Ocean for a CentOS Droplet for 10 USD/month and ran OXAR on there. It took me about 1 hour to be up and running (mostly the OXAR script was running by itself).

DockerDocker has gained a lot of popularity in the last years (since 2013/2014). Docker is a tool designed to make it easier to create, deploy, and run applications by using containers. Oracle provides official Docker Images for many of their products, see also the Docker store. If you're new to Docker, you can read more here. I also like this article which covers the main benefits of Docker. You can also watch this video how to build and deploy an Oracle Database Docker Image to the Oracle Container Cloud Service. So far I've used Docker only for test instances.

I typically use the docker image of Daniel Hochleitner (aka Mr. APEX Plugin). Daniel itself says his docker image isn't very "dockerish" because installing all components in one container is not the concept how it should work, so the benefits of microservices, security, single components and things like that are lost in a cloud environment with this particular docker image. But the nice thing about this image, just like OXAR, it includes all you need: ORDS, APEX, Tomcat, AOP, ... For me this image is ideal to test something quickly. A docker container has less overhead than a full VM and you still have some benefits of Docker.

Some pictures while building and creating the container:

For the multiplication table project I won't use this option. But I did want to cover it, as it might be a good solution for you, especially if your company is already into containers. Oh and did you know Docker has a competitor too? It's called rkt, we will probably hear more about that in the coming years.
Hosting companiesNext to Oracle, there're a number of hosting companies that provide Oracle APEX hosting, but I've no experience using them for my own projects, but it might be an option for yours. I know some AOP cloud customers that connect from their SkillBuilders, Revion and AppsHosting account.
CloudAs previously mentioned in the on-premise section, there're a number of options you have. You can just go with a (virtual) machine, or a machine that is pre-configured, a complete managed machine and database etc. They also call it infrastructure as a service (IaaS), platform as a service (PaaS) or software as a service (SaaS) or data as a service (DaaS). For an Oracle APEX project it's most important you have the Oracle database. Oracle put the last few years a lot of focus on the cloud, here you find the Oracle Database Cloud offering. There're also alternatives by many other providers for example Amazon AWS: EC2 (virtual machine), RDS (managed database) etc. In the next section we go in more detail with one of the Oracle's offering.
Oracle Exadata Express Cloud ServiceI'm a real fan of one of Oracle's cloud solutions named Oracle Exadata Express Cloud. I find this a great solution for many of my Oracle APEX projects. For 152 euro (excl. vat) you get an Oracle 12c pluggable database with many Enterprise Edition features turned on and ORDS and APEX 5.1 installed. This service is also fully managed by Oracle, so Oracle is taking care of all the patching, keeping it up and running, performant and secure. They let you know when a maintenance will happen and let you know when it's complete. Here's an example of a few days ago:

On top of this, it's running on Exadata hardware. To build this solution myself would require a lot of money. Oh and it can connect to our APEX Office Print cloud service, so you can do PDF printing and exporting to Excel too :)

But that is not all... you get more, you get a complete development infrastructure, meaning part 1 and part 2 I touched on at the start of this blog. So you can manage the full development life cycle with this service. You have a Git repository, can do the planning, capture issues, do automated builds etc.

Here's a quick screen cast logging in to Exadata Express and looking at the different pieces we covered:

On the management part of the development process; doing the builds, tracking the issues etc. you can definitely set this up yourself, and there are many options you have, from open source to probably most known, the Atlassian stack with Jira, Confluence, Bamboo etc. but this comes with a cost too. At APEX R&D we use different tools depending the project and customer. Two years ago, for AOP we started with Team Development which is part of Oracle APEX to define the features, gather feedback and define the releases. But we extended with other tools now like Trello and Bitbucket which stores our Git repository and we started to use the issue features there too. In some other projects we use Jira or Redmine.

There're so many tools to manage your development life cycle, at some point you just have to make a choice. At the end of the day most tools are good, it comes down to personal preference. Whenever our project involves Oracle Exadata Express, my choice will be to use the tools that come with the Oracle Developer Cloud Service, as that is included and I don't need to setup anything else anymore. From a maintenance and cost perspective I find it really appealing.

On different Oracle conferences this year, I've given a presentation how to move your APEX app to the Oracle Exadata Express Cloud.

Is this solution perfect yet? No, there's still room for improvement. For example I would love to have some more EE features available (RAS, Flashback data archive for example), an easier way to point to a custom URL and a customizable backup strategy. Oracle is improving every month and for many projects the current feature set is more than enough.

As the multiplication project has both an educational side to show you how I do APEX projects and is also a real use case, I'll use the Oracle Exadata Express service.

Ok, this post is getting close to 2000 words... if you read till here, great! I hope I gave you an insight in the different options you have to build your APEX infrastructure.

If you have any questions or remarks, don't hesitate to add them as comments to this post.

List of the tools I use and why I use them

Dimitri Gielis Blog - Tue, 08/08/2017 - 07:00
This post is part of a series of posts: From idea to app or how I do an Oracle APEX project anno 2017

I initially thought to only list the software tools I use, but tools are more than software alone. As a developer I find it important you have everything you need to be successful. For me that means a clean desk, a whiteboard, paper and some writing material (as explained in my previous post) and top notch hardware. Here's a picture of my desk:

So lets move on to the software part now, but before reading further, lets start with a quote I came up with ;)

The tools don’t make the developer - Dimitri Gielis
or another quote I like a lot, sent in by Alan Rintoul:

The single most important component of a camera is the twelve inches behind it – Ansel Adams
When doing development, it's not about the tools, it's about mindset. Tools can help achieve a goal, but which tool to use depends on you and how you work with them. I love to hear what and how other people are using tools to get the job done. Martin D'Souza showed in this podcast how he works with Atom (text editor) and why you should use it. I loved the podcast, Martin is a very smart guy and good developer, but you can look at this podcast in two different ways. You can look at it and say, I'm going to use Atom now, and work with Atom the same as you did in Notepad, or you can look at the principles he explains why he went with Atom and apply it to your editor of choice (which might be Atom, Sublime or another). I recently switched to Visual Studio Code as my main editor, because for me it worked better in the job I have to do a lot (read large JSON files, work with Markdown and Git). Does it mean everybody should switch? Not at all, whatever works for you.

So having said that, I thought it would be nice to list the (software) tools I use and order them by how frequently I use them. There're apps I use multiple times a day (daily), some I use multiple times a week (weekly) or just a few times a month (monthly). While compiling this list I also saw I still have apps installed I don't use that frequently at all. The below list contains only desktop applications I installed on my laptop, next to those programs I also use some webapps like Bitbucket and Trello to name a few, but I'll cover those in future posts as part of different sections. Same applies for plugins or command line apps.

Note: I've a Mac laptop with macOS, so the below applications might not exist for Windows.
  • Mail: for my emails I use Mail that is included in OSX. I also use Google Mail for other mailboxes.
  • Safari (Chrome, Firefox): I typically develop in Safari or Chrome. Safari is a bit more battery friendly, but Chrome has beter developer tools and plugins. Firefox I use when I need just another browser to see if something behaves the same.
  • Visual Studio Code: My favorite editor, I plan to do a quick video how I work with Visual Studio Code and will update this post when done placeholder for video
  • Oracle APEX: the obvious development tool of choice :) (technically not a desktop app, but belongs here anyway)
  • SQL Developer: My favorite editor to have a window in my Oracle databases. I plan to record a quick video how I work with SQL Developer and will update this post when done placeholder for video
  • TweetBot: a few times a day I check my Twitter account or the news of #orclapex
  • Slack: at my company or with friends we use Slack to communicate with each other when we are remote. There's also an orclapex team where many people of the Oracle APEX community are in
  • 1Password: with this little tool I can have all different and secure passwords, accessible with a click
  • Dropbox, Google Drive, iCloud: most important documents are in the cloud with one of those services
  • Pushbullet: sents me notifications of the server on all my devices
  • iTerm2: my window to the server or whenever I need a terminal
  • SourceTree (Git): here I've all my connections to Git repositories and I can quickly see when and what was changed
  • SQLcl: mostly used when I want to run scripts, or used behind the scenes with automation
  • Node.js: mostly used by other programs like Visual Studio Code or APEX Office Print during development
  • Gulp: I use it to automate some things, for example when I save a Markdown file in Visual Studio Code it will automatically build an html file for me
  • VMware: when I need to have a Windows machine or want to test something in my OXAR VM
  • MS Office 365: Word, Excel, Powerpoint: I use to create or edit documents for example with track changes or I'm using it to create templates for APEX Office Print
  • GotoMeeting, Skype, Zoom, Webex, TeamViewer, Google: when connecting to customers, friends, we use any of those meeting tools
  • Moom: a little window manager for OSX, which allows me to quickly see two windows next to each other
MonthlyInstalled, but not using that often
  • TextExpander: snippets manager, this one I actually plan to use more
  • XCode: used when building native iOS apps or compiling Cordova apps
  • VirtualBox: when testing Oracle Developer VMs
  • Paw: a REST manager, but I'm using Visual Studio Code plugin for that now
  • The Unarchiver: when getting files from customers to unpack them
  • Letter Opener for macOS Mail: some people send windows mails, without this tool I can't read it on OSX
  • Duet: enables my iPad as second screen, only used when travelling
  • Kaleidoscope: to compare two files (if they are not in Git)
  • Classeur: used when writing in Markdown for my Blog, but replaced it with Visual Studio Code
  • BBEdit, Atom, Sublime Text: replaced with Visual Studio Code
  • OmniPlan: used for planning
  • Patterns: to try regular expressions
  • MacDown: used to create Markdown files, for example most of the AOP documentation was written in here, but using Visual Studio Code now
  • LibreOffice: used in combination with AOP
  • Pages, Numbers: to exchange or read older files I wrote in Pages or Numbers
  • MJML: to write responsive emails
The above are just some tools that help me doing my job. Over time I changed tools and will most likely use others in the future. So depending when you read this (after 2017) things might have changed.

Feel free to share your favorite tools in the comments section.

Create user stories and supporting ERD

Dimitri Gielis Blog - Mon, 08/07/2017 - 07:19
This post is part of a series of posts: From idea to app or how I do an Oracle APEX project anno 2017

In the first post we defined our high level idea of our application. Now what are the real requirements? what does the app has to do? In an Agile software development approach we typically create user stories to define that. We write sentences in the form of:
As a < type of user >, I want < some goal > so that < some reason >Goal of defining user storiesThe only relevant reason to write user stories is to have a discussion with the people you're building the application for. To developers those stories give an overview of what is expected before the development is started in a language that all parties understand.

Some people might like to write a big requirements document, but for me personally I just don't like that (neither to read or to write). I really want to speak to the people I'm going to build something for, to get in their body and skin and really understand and feel their pain. If somebody gives me a very detailed requirements document, they don't give me much freedom. Most people don't even know what is technically possible or what could really help them.

I like this quote of Henry Ford which illustrates the above:

If I had asked people what they wanted, they would have said faster horses.

Now having said that, you have to be really careful with my statement above... it really depends the developer if you can give them freedom or not. I know many developers who are the complete opposite of me and just want you to tell them exactly what and how to build. Same applies to people who have a bright idea, they do know what would help them. I guess it comes down to, use each others strength and be open and supportive during the communication.
User stories for our projectIn our multiplication table project we will write user stories for three different types of users: the player (child), the supervisor (parent/teacher) and the administrator of the app.
  • As a player, I want to start a session so that I can practice
  • As a player, I want to practice multiplications so that I get better at multiplying
  • As a player, I want to see how I did so that I know if I improved, stayed the same or did worse
  • As a player, I want to compare myself to other people so that I get a feeling of my level
  • As a supervisor, I want to register players so that they can practice
  • As a supervisor, I want to start the session so that player can practice
  • As a supervisor, I want to choose the difficulty level so that the player gets only exercises he's supposed to know
  • As a supervisor, I want to get an overview of the players progress and achievements
  • As a supervisor, I want to get an overview of the players mistakes
  • As a supervisor, I want to print a certificate so the player feels proud of it's achievement
  • As an administrator, I want to see the people who registered for the app so that I have an overview how much the app is used
  • As an administrator, I want to add, update and remove users so that the application can be maintained
  • As an administrator, I want to see statistics of the site so that I know if it's being used
The above is not meant to be a static list, in contrary, whenever we think of something else, we will come back to the list and add more sentences. So far I took the role as administrator and parent, my son as child and my father as teacher to come to this list. I welcome more peoples ideas, so feel free to add more user stories in the comment field of things you think of. More info on user stories and how to write them you find here.
More on Agile, Scrum, Kanban, XPBefore we move on with what I typically do after having discussed the requirements with the people, I want to touch on some buzz-words. I guess most companies claim they do Agile software development. Most popular Agile software development frameworks are Scrum, Kanban and XP. I'm by far an expert in any of those, but for me it all comes down to make the team more efficient to deliver what is really needed.

My company and I are not following any of those frameworks to the letter, instead we use a mix of all. We have a place where we note all the things we have to do (backlog), we developed iteratively and ship versions frequently (sprints), we have coding standards, we limit the work in progress (WIP) etc.

When we are doing consulting or development we adapt to how the customer likes to work. It also depends a bit the size of the project and team that is in place.

So my advice is, do whatever works best for you and your team. The only important thing at the end of the day is that you deliver (in time, on budget and what is needed) :)
Thinking in relational modelsSo when I really understand the problem, my mind starts to think in an entity relational diagram or in short ERD. I don't use any tool just yet, a few pieces of paper is all I need. I start writing down words, draw circles and relations, in fact those will become my tables, columns and foreign keys later on. For me personally drawing an ERD really helps me moving to the next step of seeing what data I will have and how I should structure it. I read the user stories one by one and see if I have a table for the data to build the story. I write down the ideas, comments and questions that pop-up and put it on a cleaner piece of paper. This paper is again food for discussion with the end-users.

Here are the papers for the multiplication table project:

Our ERD is not that complicated I would say; we basically need a table to store the users who will connect to the site/app. I believe in first instance it will most likely be parents or teachers who are interested in this app. Every user has the "user" role, but some will have the administrator role, so the app can be managed. We could also use a flag in the user table to specify who's an admin, but I like to have a separate table for roles as it's more flexible, for example if we wanted to make a difference between a teacher and parent in the future. Once you are in the app you create some players, most likely your children. Those players will play games and every game consists out of some details, for example which multiplication they did.

While reading the user stories, we also want some rankings. In the above ERD I could create the players own ranking, or the ranking of the players of a user (supervisor), but it's not that flexible. That is why I added the concept of teams. A player can belong to one or more teams, so I could create a specific team where my son and I belong too, so we can see each others rank in that team, but I can also create a team of friends. The team concept makes it even flexible for teachers, so they can create their classes and add players to a specific class.

I also added a note that instead of a custom username/password, it might be interesting to add a social login like Facebook, just so the app is even easier to be accessed. As I know in Oracle APEX 5.2 social authentication will be included, I will hold off to build it myself for now, but plan to upgrade our authentication scheme once Oracle APEX 5.2 comes out.

So my revised version of the ERD looks like this:

I hope this already gives some insight in the first steps I do when starting a project.

In the above post I didn't really go into the tools to support the Agile software development (as I didn't use it yet), that is for another post.

If you have questions, comments or want to share your thoughts, don't hesitate to put a comment to this post.

From idea to app or how I do an Oracle APEX project anno 2017

Dimitri Gielis Blog - Sat, 08/05/2017 - 16:30
For a long time I had in mind to write in great detail how I do an Oracle APEX project from A to Z. But so far I never took the time to actually do it, until today :)

So here's the idea; I love building projects that help people and I love to share what I know, so I will combine both. I will write exactly my thoughts and things I do as I'm moving along with this project, so you have full insight what's happening behind the scenes.
BackgroundWay back, in the year 1999, I build an application in Visual Basic to help children study the multiplication tables. My father was a math teacher and taught people who wanted to become primary school teachers. While doing the visits of the primary schools, he saw the problem that children had difficulties to automate the multiplications from 1 till 10, so together we thought about how we could help them. That is how the Visual Basic application was born. I don't have a working example anymore of the program, but I found some paper prints from that time, which you see here:

We are now almost 20 years later and last year my son had difficulties memorizing the multiplication tables too. I tried sitting next to him and help him out, but when things don't go as smooth as you hope... You have to stay calm and supportive, but I found it hard, especially when there are two other children crying for attention too or you had a rough day yourself... In a way I felt frustrated because I didn't know how to help further in the time I had. At some point I thought about the program I wrote way back then and decided to quickly build a web app that would allow him to train himself. And to make it more fun for him, I told him I would exercise too, so he saw it was doable :)

At KScope16 I showed this web app during Open Mic Night; it was far from fancy, but it did the job.
Here's a quick demo:

Some people recognized my story and asked if I could put the app online. I just build the app quickly for my son, so it needs some more work to make it accessible for others.
During my holidays, I decided I should really treat this project as a real one, otherwise it would never happen, so here we are, that is what I'm going to do and I'll write about it in detail :)
Idea - our requirementThe application helps children (typically between 7 and 11 years old) to automate multiplications between 1 and 10. It also helps their parents to get insight in timings and mistakes of their children's multiplications.
TimelineNo project without deadline, so I've set my go-production date to August 20th, 2017. So I've about 2 weeks, typically one sprint in our projects.
Following along and feedbackI will tweet, blog and create some videos to show my progress. You can follow along and reach me on any of those channels. If you have any questions, tips or remarks during the development, don't hesitate to add a comment. I always welcome new ideas or insights and am happy to go in more detail if something is not clear.
High level break-down of plan for the following days
  • Create user stories and supporting ERD
  • List of the tools I use and why I use them
  • Set up the development environment
  • Create the Oracle database objects
  • Set up a domain name
  • Set up reverse proxy and https
  • Create a landing page and communicate
  • Build the Oracle APEX application: the framework
  • Refine the APEX app: create custom authentication
  • Refine the APEX app: adding the game
  • Refine the APEX app: improve the flow and navigation
  • Refine the APEX app: add ability to print results to PDF
  • Set up build process
  • Check security
  • Communicate first version of the app to registered people
  • Check performance
  • Refine the APEX app: add more reports and statistics
  • Check and reply to feedback
  • Set up automated testing
  • A word on debugging
  • Refine the APEX app: making final changes
  • Set up backups
  • Verify documentation and lessons learned
  • Close the loop and Celebrate :)
So now, let's get started ...

Basic Index Compression Made Simple (It Ain’t Easy)

Richard Foote's Blog - Wed, 08/02/2017 - 02:07
I’ve discussed Index Compression a number of times as it’s an excellent way of minimizing the size of indexes without unnecessary, expensive index rebuilds. One of the nice features of Advanced Index Compression is that not only does it potentially compress indexes more effectively than possible with Basic Index Compression, but that it also eliminates […]

12.2 Introduction to Real-Time Materialized Views (The View)

Richard Foote's Blog - Mon, 07/10/2017 - 07:23
Although I usually focus on index related topics, I’ve always kinda considered Materialized Views (MVs) as an index like structure, which Oracle can automatically update and from which Oracle can efficiently retrieve data. The cost of maintaining a Materialized View Log is not unlike the cost of maintaining an index structure, the benefits of which […]
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