I really liked David McFarland’s CSS: The Missing Manual when it came out in 2009, and I’ve recommended it for several years. However, he’s got a new version – CSS3: The Missing Manual that came out in late January 2014. It’s an improvement over his first volume and I’d recommend you upgrade if you’re writing, modifying, or maintaining Cascading Style Sheet or if you just want to learn more about CSS.
Fortunately for me, CSS3: The Missing Manual is available through iTunes for Apple users, Naturally, it’s also available on Safari and Kindle formats. As an Apple user, I opted for the iBook format for my iPad Air. Unfortunately, it’s $27.99 as an iBook compared to $15.49 on Kindle, and that almost makes me opt to use the Kindle App.
In prior years a daily update from Open World was possible, but this year my schedule was too full to support it. This is my compendium of thoughts about MySQL Connect, JavaOne, and Open World 2012.
MySQL Connect was great – good sessions re-enforcing the positive investments Oracle is making in the product. I’ll leave to others to qualify changes in what elements of technology are opened or closed along the road to a better MySQL. The announcement of Connector/Python 1.0 GA on Saturday was great news and as a community we owe a lot to Greet Vanderkelen.
NoSQL is a hot topic along with using JSON objects and it was interesting hearing of some unequal testing paradigms to position non-Oracle solutions to be “better” than Oracle solutions. Naturally, the MongoDB was the elephant in the room during those conversations. Some of the discussions seemed more like political rants than technical dialog. A great spot to start with NoSQL and JSON would be downloading Oracle’s MySQL 5.6 Release Candidate.
There were also more PostgreSQL conversations this year and fairly accurate comparisons between it and Oracle or MySQL from folks. It certainly looks like it may gain more ground.
Java 7 is awesome, and my favorite feature is clearly NIO2, reinforced at JavaOne. NIO2 brings static methods to interactions with external directory and file sources. It removes directories from the files class, which is long overdue. The nature of those static methods also happen to fit within the definition of Java code that lives inside the Oracle database and gives me a whole host of thoughts about potential in Oracle Database 12c.
Larry Ellison’s keynote was impressive because it gives us a clear vision of Oracle’s direction and Duncan Davies captured the keynote well in his blog. The continued presence of Red Hat and VMWare offers interesting reality checks to their key contributions to world wide implementation of the Oracle technical stack.
Issues that seem most critical to those I’ve chatted with are storage, security, tools, and development languages. A nice update on security can be found in the new edition of Hacking Exposed 7: Network Security Secrets & Solutions (7th Edition).
On the forthcoming Oracle 12c release, Information Week just released a good summary view. The introduction of the R programming language on the Exadata Server leads me to wonder about what uses may magically appears in Oracle Enterprise Manager down the road. The TIOBE Index for September 2012 doesn’t list the R language in the top 20 programming languages but there’s always the future. No mention of Erlang programming language at any of the conferences that I caught but it’s inevitably on the horizon as application servers evolve.
Now we wait for the Oracle Database 12c release, which looks like something in the very short term. Perhaps right after the holidays …
The topic of WebSockets came up today, and it seems a good idea to qualify WebSockets in the blog beyond simply pointing folks to Kaazing. HTML5’s WebSockets are a great fix for the half-duplex world of AJAX. They certainly have the potential to be more scalable than current Comet solutions, and present a real-time communication alternative. The latest draft of The WebSocket API was published earlier this month.
If you’re new to WebSockets, you may want to review Peter Lubbers’ PowerPoint presentation from the International Conference on Java Technology, 2010 (or the updated version he provided via a comment to this post). That is probably shorter than watching the multiple parts posted in 10-minute segments on YouTube.
As Peter Lubbers qualifies, AJAX and COMET solutions don’t scale against high transaction volumes or concurrency because their header traffic overwhelms the actual data transfers. This reality occurs more or less because browsers only implement unidirectional communication through a request and acknowledgement model and send large header sequences compared to small data footprints.
Peter Lubbers presents three types of HTTP solutions in the presentation:
- Polling involves periodic requests to the server for updated information, and it is the backbone of many Ajax applications that simulate real-time communication. The HTTP message headers involved in polling are frequently larger than the transmitted data; and while polling works well in low-message rate situations it doesn’t scale well. It also involves opening and closing many connections to the server and hence database needlessly in some cases.
- Long Polling or asynchronous-polling requests the server to keep the connection open for a set period of time. It doesn’t solve problems with high-message rates situations of polling in general because it creates a continuous loop of immediate polls and each poll, like ordinary polling messages, sends mostly HTTP headers not data.
- Streaming architecture opens a socket but can cause problems with proxy and firewall servers, create cross-domain issues due to browser connection limits, and periodically pose overhead to flush streams that have built up in the communication channel. Streaming solutions reduce HTTP header traffic but at a cost in overhead to the server.
Websockets are designed to fix these issues. The most interesting thing about polling, long polling, streaming, or Websockets is they require the same careful attention to how databases validate user access and serve up content. When the HTML5 standard nears completion, they’ll be a great need for database connection solutions, like Oracle’s Data Resident Connection Pooling.
By the way, here are some great video links for learning HTML5.