Search Results

Search found 4596 results on 184 pages for 'moderately interesting'.

Page 161/184 | < Previous Page | 157 158 159 160 161 162 163 164 165 166 167 168  | Next Page >

  • SUPINFO International University in Mauritius

    Since a while I'm considering to pick up my activities as a student and I'd like to get a degree in Computer Science. Personal motivation I mean after all this years as a professional software (and database) developer I have the personal urge to complete this part of my education. Having various certifications by Microsoft and being awarded as an Microsoft Most Valuable Professional (MVP) twice looks pretty awesome on a resume but having a "proper" degree would just complete my package. During the last couple of years I already got in touch with C-SAC (local business school with degree courses), the University of Mauritius and BCS, the Chartered Institute for IT to check the options to enroll as an experienced software developer. Quite frankly, it was kind of alienating to receive that feedback: Start from scratch! No seriously? Spending x amount of years to sit for courses that might be outdated and form part of your daily routine? Probably being in an awkward situation in which your professional expertise might exceed the lecturers knowledge? I don't know... but if that's path to walk... Well, then I might have to go for it. SUPINFO International University Some weeks ago I was contacted by the General Manager, Education Recruitment and Development of Medine Education Village, Yamal Matabudul, to have a chat on how the local IT scene, namely the Mauritius Software Craftsmanship Community (MSCC), could assist in their plans to promote their upcoming campus. Medine went into partnership with the French-based SUPINFO International University and Mauritius will be the 36th location world-wide for SUPINFO. Actually, the concept of SUPINFO is very likely to the common understanding of an apprenticeship in Germany. Not only does a student enroll into the programme but will also be placed into various internships as part of the curriculum. It's a big advantage in my opinion as the person stays in touch with the daily procedures and workflows in the real world of IT. Statements like "We just received a 'crash course' of information and learned new technology which is equivalent to 1.5 months of lectures at the university" wouldn't form part of the experience of such an education. Open Day at the Medine Education Village Last Saturday, Medine organised their Open Day and it was the official inauguration of the SUPINFO campus in Mauritius. It's now listed on their website, too - but be warned, the site is mainly in French language although the courses are all done in English. Not only was it a big opportunity to "hang out" on the campus of Medine but it was great to see the first professional partners for their internship programme, too. Oh, just for the records, IOS Indian Ocean Software Ltd. will also be among the future employers for SUPINFO students. More about that in an upcoming blog entry. Open Day at Medine Education Village - SUPINFO International University in Mauritius Mr Alick Mouriesse, President of SUPINFO, arrived the previous day and he gave all attendees a great overview of the roots of SUPINFO, the general development of the educational syllabus and their high emphasis on their partnerships with local IT companies in order to assist their students to get future jobs but also feel the heartbeat of technology live. Something which is completely missing in classic institutions of tertiary education in Computer Science. And since I was on tour with my children, as usual during weekends, he also talked about the outlook of having a SUPINFO campus in Mauritius. Apart from the close connection to IT companies and providing internships to students, SUPINFO clearly works on an international level. Meaning students of SUPINFO can move around the globe and can continue their studies seamlessly. For example, you might enroll for your first year in France, then continue to do 2nd and 3rd year in Canada or any other country with a SUPINFO campus to earn your bachelor degree, and then live and study in Mauritius for the next 2 years to achieve a Master degree. Having a chat with Dale Smith, Expand Technologies, after his interesting session on Technological Entrepreneurship - TechPreneur More questions by other craftsmen of the Mauritius Software Craftsmanship Community And of course, this concept works in any direction, giving Mauritian students a huge (!) opportunity to live, study and work abroad. And thanks to this, Medine already announced that there will be new facilities near Cascavelle to provide dormitories and other facilities to international students coming to our island. Awesome! Okay, but why SUPINFO? Well, coming back to my original statement - I'd like to get a degree in Computer Science - SUPINFO has a process called Validation of Acquired Experience (VAE) which is tailor-made for employees in the field of IT, and allows you to enroll in their course programme. I already got in touch with their online support chat but was only redirected to some FAQs on their website, unfortunately. So, during the Open Day I seized the opportunity to have an one-on-one conversation with Alick Mouriesse, and he clearly encouraged me to gather my certifications and working experience. SUPINFO does an individual evaluation prior to their assignment regarding course level, and hopefully my chances of getting some modules ahead of studies are looking better than compared to the other institutes. Don't get me wrong, I don't want to go down the easy route but why should someone sit for "Database 101" or "Principles of OOP" when applying and preaching database normalisation and practicing Clean Code Developer are like flesh and blood? Anyway, I'll be off to get my transcripts of certificates together with my course assignments from the old days at the university. Yes, I studied Applied Chemistry for a couple of years before intersecting into IT and software development particularly... ;-)

    Read the article

  • IBM Keynote: (hardware,software)–>{IBM.java.patterns}

    - by Janice J. Heiss
    On Sunday evening, September 30, 2012, Jason McGee, IBM Distinguished Engineer and Chief Architect Cloud Computing, along with John Duimovich IBM Distinguished Engineer and Java CTO, gave an information- and idea-rich keynote that left Java developers with much to ponder.Their focus was on the challenges to make Java more efficient and productive given the hardware and software environments of 2012. “One idea that is very interesting is the idea of multi-tenancy,” said McGee, “and how we can move up the spectrum. In traditional systems, we ran applications on dedicated middleware, operating systems and hardware. A lot of customers still run that way. Now people introduce hardware virtualization and share the hardware. That is good but there is a lot more we can do. We can share middleware and the application itself.” McGee challenged developers to better enable the Java language to function in these higher density models. He spoke about the need to describe patterns that help us grasp the full environment that an application needs, whether it’s a web or full enterprise application. Developers need to understand the resources that an application interacts with in a way that is simple and straightforward. The task is to then automate that deployment so that the complexity of infrastructure can be by-passed and developers can live in a simpler world where the cloud can automatically configure the needed environment. McGee argued that the key, something IBM has been working on, is to use a simpler pattern that allows a cloud-based architecture to embrace the entire infrastructure required for an application and make it highly available, scalable and able to recover from failure. The cloud-based architecture would automate the complexity of setting up and managing the infrastructure. IBM has been trying to realize this vision for customers so they can describe their Java application environment simply and allow the cloud to automate the deployment and management of applications. “The point,” explained McGee, “is to package the executable used to describe applications, to drop it into a shared system and let that system provide some intelligence about how to deploy and manage those applications.”John Duimovich on Improvements in JavaMcGee then brought onstage IBM’s Distinguished Engineer and CTO for Java, John Duimovich, who showed the audience ways to deploy Java applications more efficiently.Duimovich explained that, “When you run lots of copies of Java in the cloud or any hypervisor virtualized system, there are a lot of duplications of code and jar files. IBM has a facility called ‘shared classes’ where we put shared code, read only artefacts in a cache that is sharable across hypervisors.” By putting JIT code in ahead of time, he explained that the application server will use 20% less memory and operate 30% faster.  He described another example of how the JVM allows for the maximum amount of sharing that manages the tenants and file sockets and memory use through throttling and control. Duimovich touched on the “thin is in” model and IBM’s Liberty Profile and lightweight runtime for the cloud, which allows for greater efficiency in interacting with the cloud.Duimovich discussed the confusion Java developers experience when, for example, the hypervisor tells them that that they have 8 and then 4 and then 16 cores. “Because hypervisors are virtualized, they can change based on resource needs across the hypervisor layer. You may have 10 instances of an operation system and you may need to reallocate memory, " explained Duimovich.  He showed how to resize LPARs, reallocate CPUs and migrate applications as needed. He explained how application servers can resize thread pools and better use resources based on information from the hypervisors.Java Challenges in Hardware and SoftwareMcGee ended the keynote with a summary of upcoming hardware and software challenges for the Java platform. He noted that one reason developers love Java is it allows them to ignore differences in hardware. He stated that the most important things happening in hardware were in network and storage – in developments such as the speed of SSD, the exploitation of high-speed, low-latency networking, and recent developments such as storage-class memory, and non-volatile main memory. “So we are challenged to maintain the benefits of Java and the abstraction it provides from hardware while still exploiting the new innovations in hardware,” said McGee.McGee discussed transactional messaging applications where developers send messages transactionally persist a message to storage, something traditionally done by backing messages on spinning disks, something mostly outdated. “Now,” he pointed out, “we would use SSD and store it in Flash and get 70,000 messages a second. If we stored it using a PCI express-based flash memory device, it is still Flash but put on a PCI express bus on a card closer to the CPU. This way I get 300,000 messages a second and 25% improvement in latency.” McGee’s central point was that hardware has a huge impact on the performance and scalability of applications. New technologies are enabling developers to build classes of Java applications previously unheard of. “We need to be able to balance these things in Java – we need to maintain the abstraction but also be able to exploit the evolution of hardware technology,” said McGee. According to McGee, IBM's current focus is on systems wherein hardware and software are shipped together in what are called Expert Integrated Systems – systems that are pre-optimized, and pre-integrated together. McGee closed IBM’s engaging and thought-provoking keynote by pointing out that the use of Java in complex applications is increasingly being augmented by a host of other languages with strong communities around them – JavaScript, JRuby, Scala, Python and so forth. Java developers now must understand the strengths and weaknesses of such newcomers as applications increasingly involve a complex interconnection of languages.

    Read the article

  • Silverlight Cream for December 18, 2010 -- #1012

    - by Dave Campbell
    In this Issue: Mark Monster, Kevin Dockx, Jeremy Likness(-2-,-3-), Timmy Kokke, Den Delimarsky, Mike Snow, Samuel Jack(-2-), and Renuka Prasad(-2-). Above the Fold: Silverlight: "Trigger a Storyboard on ViewModel changes" Mark Monster WP7: "Microsoft Push Notification in Windows Phone 7" Renuka Prasad Shoutouts: SilverlightGal sent me the link to The Silverlight Dossier ... I think it's a pretty good start... additions I'd like to see are ways to submit to the various areas. Michael Crump put up a contest that runs from now to January 1st... Win a set of Infragistics Silverlight Controls with Data Visualization!... pretty cool, Michael! If you visit WynApse.com, you'll see I have a subscription to LearnVisualStudio.net... and now they have posted a batch of WP7 videos... 64 of them to be exact... wow!: New video series From SilverlightCream.com: Trigger a Storyboard on ViewModel changes Mark Monster has a great post up about triggering Storyboard on ViewModel changes using the DataTrigger from Blend... cool stuff, and you can also do GoToStateAction or other actions or build yourowndang Trigger Action... fun awaits! ... sorry it took a while to post, Mark... been a tad overloaded here! Working with the Silverlight Rich Text Box control Kevin Dockx has had a post up for a while at SilverlightShow where he takes a good look at the RichText control and it's various capabilities, including source so you can give it a dance yourself. Lessons Learned in Personal Web Page Part 3: Custom Panel and Listbox Jeremy Likness's part 3 of his Personal Web Page lessons learned is covering the tres-cool 3D Panel he did... and he's got it all explained out... building from scratch via a custom panel and a Listbox control... A Silverlight MVVM Feed Reader from Scratch in 30 Minutes Jeremy Likness has a video tutorial showing building an MVVM/Silverlight feedreader in 30 minutes ... plus a couple mods that he noticed after the fact... beat that HTML5 :) Jounce Part 8: Raising Property Changed In Jeremy Likness's latest post, he has number 8 in his series on his MVVM platform, Jounce. This time he's explaining the property changed notification, has a very cool way of doing it, and some interesting comments from readers. Dependency Injection, MVVM, Ninject and Silverlight Timmy Kokke has a great tutorial up with associated demo project on Dependency Injection in MVVM and Silverlight. Some hidden features in the Windows Phone 7 emulator Den Delimarsky shows how to get some of the hidden features on your WP7 emulator like the Call History, Call Settings, and Details about the numbers. Playing sound effects on Windows Phone 7 Mike Snow's latest tip is playing sound effects on your WP7 ... a little bit of XNA here and there, and badabing, badaboom, you got sound! Day 3 of my “Build a Windows Phone 7 game in 3 days” Challenge Samuel Jack has a couple more posts up about his 'Build a WP7 game in 3 Days' challenge... first up is Day 3 from 8:50 to 22:30 ... wow... long day! ... but he's got something good going now... some good external links also Day 3.5 of my “Build a Windows Phone 7 game in 3 days” Challenge Samuel Jack's 3rd day ended with another half-day added on to put on some finishing touches... again, some good external links... and he finished with this Say hello to Simon Squared, my 3.5 day old WP7 Game Microsoft Push Notification in Windows Phone 7 Renuka Prasad has a bunch of material up that I've not been aware of (how did that happen, people??) ... here's the first of a couple of his posts on Code Project ... a very nice tutorial on the Push Notification process... great diagrams and external links. Windows Phone 7 – Toast Notification Using Windows Azure Cloud Service Renuka Prasad has another WP7 post on CodeProject... this one on Toast Notification... and he's using Azure and WCF all rolled into it as well... great diagrams, descriptions and all the code. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

    Read the article

  • Why would GLCapabilities.setHardwareAccelerated(true/false) have no effect on performance?

    - by Luke
    I've got a JOGL application in which I am rendering 1 million textures (all the same texture) and 1 million lines between those textures. Basically it's a ball-and-stick graph. I am storing the vertices in a vertex array on the card and referencing them via index arrays, which are also stored on the card. Each pass through the draw loop I am basically doing this: gl.glBindBuffer(GL.GL_ARRAY_BUFFER, <buffer id>); gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, <buffer id>); gl.glDrawElements(GL.GL_POINTS, <size>, GL.GL_UNSIGNED_INT, 0); gl.glBindBuffer(GL.GL_ARRAY_BUFFER, <buffer id>); gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, <buffer id>); gl.glDrawElements(GL.GL_LINES, <size>, GL.GL_UNSIGNED_INT, 0); I noticed that the JOGL library is pegging one of my CPU cores. Every frame, the run method internal to the library is taking quite long. I'm not sure why this is happening since I have called setHardwareAccelerated(true) on the GLCapabilities used to create my canvas. What's more interesting is that I changed it to setHardwareAccelerated(false) and there was no impact on the performance at all. Is it possible that my code is not using hardware rendering even when it is set to true? Is there any way to check? EDIT: As suggested, I have tested breaking my calls up into smaller chunks. I have tried using glDrawRangeElements and respecting the limits that it requests. All of these simply resulted in the same pegged CPU usage and worse framerates. I have also narrowed the problem down to a simpler example where I just render 4 million textures (no lines). The draw loop then just doing this: gl.glEnableClientState(GL.GL_VERTEX_ARRAY); gl.glEnableClientState(GL.GL_INDEX_ARRAY); gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT); gl.glMatrixMode(GL.GL_MODELVIEW); gl.glLoadIdentity(); <... Camera and transform related code ...> gl.glEnableVertexAttribArray(0); gl.glEnable(GL.GL_TEXTURE_2D); gl.glAlphaFunc(GL.GL_GREATER, ALPHA_TEST_LIMIT); gl.glEnable(GL.GL_ALPHA_TEST); <... Bind texture ...> gl.glBindBuffer(GL.GL_ARRAY_BUFFER, <buffer id>); gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, <buffer id>); gl.glDrawElements(GL.GL_POINTS, <size>, GL.GL_UNSIGNED_INT, 0); gl.glDisable(GL.GL_TEXTURE_2D); gl.glDisable(GL.GL_ALPHA_TEST); gl.glDisableVertexAttribArray(0); gl.glFlush(); Where the first buffer contains 12 million floats (the x,y,z coords of the 4 million textures) and the second (element) buffer contains 4 million integers. In this simple example it is simply the integers 0 through 3999999. I really want to know what is being done in software that is pegging my CPU, and how I can make it stop (if I can). My buffers are generated by the following code: gl.glBindBuffer(GL.GL_ARRAY_BUFFER, <buffer id>); gl.glBufferData(GL.GL_ARRAY_BUFFER, <size> * BufferUtil.SIZEOF_FLOAT, <buffer>, GL.GL_STATIC_DRAW); gl.glVertexAttribPointer(0, 3, GL.GL_FLOAT, false, 0, 0); and: gl.glBindBuffer(GL.GL_ELEMENT_ARRAY_BUFFER, <buffer id>); gl.glBufferData(GL.GL_ELEMENT_ARRAY_BUFFER, <size> * BufferUtil.SIZEOF_INT, <buffer>, GL.GL_STATIC_DRAW); ADDITIONAL INFO: Here is my initialization code: gl.setSwapInterval(1); //Also tried 0 gl.glShadeModel(GL.GL_SMOOTH); gl.glClearDepth(1.0f); gl.glEnable(GL.GL_DEPTH_TEST); gl.glDepthFunc(GL.GL_LESS); gl.glHint(GL.GL_PERSPECTIVE_CORRECTION_HINT, GL.GL_FASTEST); gl.glPointParameterfv(GL.GL_POINT_DISTANCE_ATTENUATION, POINT_DISTANCE_ATTENUATION, 0); gl.glPointParameterfv(GL.GL_POINT_SIZE_MIN, MIN_POINT_SIZE, 0); gl.glPointParameterfv(GL.GL_POINT_SIZE_MAX, MAX_POINT_SIZE, 0); gl.glPointSize(POINT_SIZE); gl.glTexEnvf(GL.GL_POINT_SPRITE, GL.GL_COORD_REPLACE, GL.GL_TRUE); gl.glEnable(GL.GL_POINT_SPRITE); gl.glClearColor(clearColor.getX(), clearColor.getY(), clearColor.getZ(), 0.0f); Also, I'm not sure if this helps or not, but when I drag the entire graph off the screen, the FPS shoots back up and the CPU usage falls to 0%. This seems obvious and intuitive to me, but I thought that might give a hint to someone else.

    Read the article

  • Employee Engagement Q&A with John Brunswick

    - by Kellsey Ruppel
    As we are focusing this week on Employee Engagement, I recently sat down with industry expert and thought leader John Brunswick on the topic. Here is the Q&A dialogue we shared.  Q: How do you effectively engage employees to drive business value?A: Motivation, both extrinsic and intrinsic, combined with the relevancy of various channels to support it.  Beyond chaining business strategies like compensation models within an organization, engagement ultimately is most successful when driven by employee's motivations.  Business value derived from engagement through technical capabilities can be objectively measured through metrics like the rate and accuracy of problem solving for a given business function or frequency of innovation created.  Providing employees performing "knowledge work" with capabilities that allow them to perform work with a higher degree of accuracy in the same or ideally less time, adds value for that individual and in turn, drives their level of engagement to drive business value. Q: Organizations with high levels of employee engagement outperform the total stock market index by 22%. Can you comment on why you think this might be? A: Alignment through shared purpose.  Zappos is an excellent example of a culture that arguably has higher than average levels of employee engagement and it permeates every aspect of their organization – embodied externally through their customer experience.  I recently made my first purchase with them and it was obvious through their web experience, visual design, communication style, customer service and attention to detail down to green packaging, that they have an amazingly strong shared purpose.  The Zappos.com ‘About page’ outlines their "Family Core Values", the first three being "Deliver WOW Through Service, Embrace and Drive Change & Create Fun and A Little Weirdness" – all reflected externally in my interaction with them.  Strong shared purpose enables higher product and service experience, equating to a dedicated customer base, repeat purchases and expanded marketshare. Q: Have you seen any trends in the market regarding employee engagement? A: Some companies now see offering a form of social engagement similar to Facebook and LinkedIn as standard communication infrastructure like email or instant messaging.  Originally offered as standalone tools, the value is now seen when these capabilities are offered in an integrated fashion in the context of business entities.  An emerging area of focus is around employee activities related to their organization on external social platforms, implicitly creating external communities with employees acting on behalf of the brand and interacting with each other (e.g. Twitter).  Companies have reached a formal understand that this now established communication medium requires strategies allowing employees to engage.  I have personally met colleagues from Oracle, like Oracle User Experience Director Ultan O'Broin (@ultan), via Twitter before meeting first through internal channels. Q: Employee engagement is important, but what about engaging customers and partners? A: The last few years we have witnessed an interesting evolution from the novelty of self-service to expectations of "intelligent" self-service.  From a consumer standpoint, engagement can end up being a key differentiator, especially in mature markets.  Customers that perform some level of interaction with a brand develop greater affinity for the brand and have a greater probability of acting as an advocate.  As organizations move toward a model of deeper engagement, they must ensure that their business is positioned to support deeper relationships, offering potentially greater transparency. From a partner standpoint greater engagement can lead to new types of business opportunities, much in the way that Amazon.com offers a unified shopping experience that can potentially span various vendors.  This same model can be extended to blending services and product delivery models, based on a closeness not easily possible before increased capability of engagement mechanisms. Q: What types of solutions are available to successfully deliver employee engagement? A: Solutions enabling higher levels of engagement do so on the basis of relevancy.  This relevancy is generally supported by aspects of content management, social collaboration, business intelligence, portal and process management technologies.  These technologies can help deliver an experience tailored to a given role or process within an organization that applies equally to work that is structured or unstructured, appearing in the form of functionality as simple as an online employee directory search, knowledge communities supported by social collaboration, as well as more feature rich business intelligence dashboards and portals. Looking to learn more about how to effectively engage your employees? Check out this webcast, or read more from John Brunswick. 

    Read the article

  • Is it Hard to Write a Blog?

    - by Joe Mayo
    Responding to a tweet I received, asking if I found it hard to write a blog and keep it interesting. This is one of the situations where a 140 character response doesn’t do a question justice. There’s a lot to think about between the subjects of writing, subject matter, and entertainment.  Here’s my take on each of these three topics: There’s all types of writing you can do with various degrees of difficulty. If you’re writing a book and you have a gazillion editors bleeding over your every utterance, then the task becomes harder because you’re second-guessing yourself, not knowing whose opinion will be violated. However, if you’re communicating in a public forum, not too many people care about the grammar as much as whether what you have to say is correct.  For a blog, I would say it’s somewhere in-between.  Right now, I’m using Windows Live Writer, which gives me a few advantages to just typing into the blog editor, such as spelling correction and the ability to save my work and resume later.  Overall, writing is one of those things that you just need to get used to.  It’s an essential skill for developers because you need to document your work, depending on what your definition of proper documentation is, and communicate with other developers via various communications mediums. Not begin good (or not thinking that you’re good) shouldn’t hold you back.  Like most things in life, practice will improve your skill.  So, push away that inner voice that keeps you from moving forward and just do it. A good grasp on the subject matter you’re writing about helps.  However, don’t let a lack of knowledge stop you from writing about something. I recall reading something a while back by a developer who didn’t know a technology but wrote about their experience in learning it. They ended up learning more by expressing their thoughts in writing. If you look around out many blogs today, there are many items written by developers learning what they’re writing about.  So, whether you are sure or unsure, you can still write – just be honest with yourself and your readers about what you’re writing. Also, don’t be afraid to have a different opinion or worry if someone will disagree.  I’ll freely admit that it took a while for me to become accustomed to being criticized. Take the good with the bad and use the bad to make yourself better. Guaranteed, someone will disagree with one or more parts of what I’ve written here or think they have a better approach. No problem, more power to them, and whatever constructive comments they have will be a benefit to me in the future; Otherwise, to h*ll with them. :)  Every time you get knocked down, get right back up, dust the dirt off your backside, and keep moving forward.  You’ll learn in time how to align a subject with your own presentation of the material. Entertainment could be hard or could be natural, depending on the personality of yourself and your target audience. It’s even more challenging because you can say something you think is funny and someone will be offended. In fact, there are a lot of things that you shouldn’t say in the name of a joke, but I won’t mention any of them here for want of not offending anyone. Of course, I probably offended someone by saying that and there is probably an organization somewhere in the world out to get me now. I’m probably not the best person to be giving you advice on entertaining an audience.  I mean, every time I try to tell a joke on Twitter 10 people unfriend me. Okay, maybe 15, but you get my point. One thing you might be interested in knowing is that it’s not too hard for one technical person to entertain other technical people, especially when the subject is of interest.  It’s the excitement in each sentence and passion in each paragraph that will keep another developer entertained and interested in what you have to say. Not everyone will like what you’ve written, but the important part is to find your own voice and it’s likely that there is one person in some corner of the world that likes what you have to say, even if it’s your mom and she doesn’t understand a single word you write. :)   If I could leave you with one final thought; Just do it and don’t let anyone or anything hold you back.   Joe

    Read the article

  • Architect Day: Boston - Agenda Update

    - by Bob Rhubart
    Here's the latest information on the session schedule and content for Oracle Technology Network Architect Day in Boston, MA on September 12, 2012. Registration is open, but seating is limited. When: September 12, 2012 8:30am – 5:00pm Where: Boston Marriott Burlington One Burlington Mall Road Burlington, MA 01803 Register now Agenda Time Session Title Room 8:30 am - 9:00 am Registration and Continental Breakfast Salon E Foyer 9:00 am - 9:15 am Welcome and Opening Comments | Bob Rhubart Salon E 9:15 am - 10:00 am Engineered Systems: Oracle's Vision for the Future | Ralf Dossmann Oracle's Exadata and Exalogic are impressive products in their own right. But working in combination they deliver unparalleled transaction processing performance with up to a 30x increase over existing legacy systems, with the lowest cost of ownership over a 3 or 5 year basis than any other hardware. In this session you'll learn how to leverage Oracle's Engineered Systems within your enterprise to deliver record-breaking performance at the lowest TCO. Salon E 10:00 am - 10:30 am Securing Public and Private Clouds | Anton Nielsen Long before the term "Cloud Computing" existed, Oracle technologies supported and promoted the concept. Centralized data with remote users has been at the core of these technologies for decades. The public cloud, and extending private clouds to the internet, though, has added security challenges never imagined decades ago. This presentation will examine a real life security breach and introduce architecture, technologies and policies to secure public and private clouds.  Salon E 10:30 am - 10:45 am Break 10:45 am - 11:30 am Breakout Sessions (pick one) Cloud Computing - Making IT Simple | Scott Mattoon The road to Cloud Computing is not without a few bumps. This session will help to smooth out your journey by tackling some of the potential complications. We'll examine whether standardization is a prerequisite for the Cloud. We'll look at why refactoring isn't just for application code. We'll check out deployable entities and their simplification via higher levels of abstraction. And we'll close out the session with a look at engineered systems and modular clouds. Salon E Innovations in Grid Computing with Oracle Coherence | Rob Misek Learn how Coherence can increase the availability, scalability and performance of your existing applications with its advanced low-latency data-grid technologies. Also hear some interesting industry-specific use cases that customers had implemented and how Oracle is integrating Coherence into its Enterprise Java stack. Salon C 11:30 am - 12:15 pm Breakout Sessions (pick one) Enterprise Strategy for Cloud Security | Dave Chappelle Security is high on the list of concerns for many organizations as they evaluate their cloud computing options. This session will examine security in the context of the various forms of cloud computing. We'll consider technical and non-technical aspects of security, and discuss several strategies for cloud computing, from both the consumer and producer perspectives. Salon E Oracle Enterprise Manager | Avi Huber Much more than a DB management tool, Oracle Enterprise Manager provides management and monitoring coverage for the entire Oracle stack, and beyond. This session will concentrate on the middleware management functionality in OEM, starting with Real User Experience monitoring, through AppServer management, and into deep-dive Java diagnostics. We’ll discuss Business Driven Application Management (BDAM) and the benefits of top-down monitoring. Lastly, we’ll demonstrate how to trace a specific user experience problem, through a multitier SOA application, to its root cause, deep in the JVM. Salon C 12:15 pm - 1:15 pm Lunch Salon E Foyer 1:15 pm - 2:00 pm Panel Discussion - Q&A with session speakers Salon E 2:00 pm - 2:45 pm Breakout Sessions (pick one) Oracle Cloud Reference Architecture | Anbu Krishnaswamy Cloud initiatives are beginning to dominate enterprise IT roadmaps. Successful adoption of Cloud and the subsequent governance challenges warrant a Cloud reference architecture that is applied consistently across the enterprise. This presentation will answer the important questions: What exactly is a Cloud, why you need it, what changes it will bring to the enterprise, and what are the key capabilities of a Cloud infrastructure are - using Oracle's Cloud Reference Architecture, which is part of the IT Strategies from Oracle (ITSO) Cloud Enterprise Technology Strategy (ETS). Salon E 21st Century SOA | Peter Belknap Service Oriented Architecture has evolved from concept to reality in the last decade. The right methodology coupled with mature SOA technologies has helped customers demonstrate success in both innovation and ROI. In this session you will learn how Oracle SOA Suite's orchestration, virtualization, and governance capabilities provide the infrastructure to run mission critical business and system applications. And we'll take a special look at the convergence of SOA & BPM using Oracle's Unified technology stack. Salon C 2:45 pm - 3:00 pm Break 3:00 pm - 4:00 pm Roundtable Discussion Salon E 4:00 pm - 4:15 pm Closing Comments & Readouts from Roundtables Salon E 4:15 pm - 5:00 pm Networking / Reception Salon E Foyer Note: Session schedule and content subject to change.

    Read the article

  • IndyTechFest Recap

    - by Johnm
    The sun had yet to raise above the horizon on Saturday, May 22nd and I was traveling toward the location of the 2010 IndyTechFest. In my freshly awaken, and pre-coffee, state I reflected on the months that preceded this day and how quickly they slipped away. The big day had finally come and the morning dew glistened with a unique brightness that morning. What is this all about? For those who are unfamiliar with IndyTechFest, it is a regional conference held in Indianapolis and hosted by the Indianapolis .NET Developers Association (IndyNDA) and the Indianapolis Professional Association for SQL Server (IndyPASS).  The event presents multiple tracks and sessions covering subjects such as Business Intelligence,  Database Administration, .NET Development, SharePoint Development, Windows Mobile Development as well as non-Microsoft topics such as Lean and MongoDB. This year's event was the third hosting of IndyTechFest. No man is an island No event such as IndyTechFest is executed by a single person. My fellow co-founders, with their highly complementary skill sets and philanthropy make the process very enjoyable. Our amazing volunteers and their aid were indispensible. The generous financial support of our sponsors that made the event and fabulous prizes possible. The spectacular line up of speakers who came from near and far to donate their time and knowledge. Our beloved attendees who sacrificed the first sunny Saturday in weeks to expand their skill sets and network with their peers. We are deeply appreciative. Challenges in preparation With the preparation of any event comes challenges. It is these challenges that makes the process of planning an event so interesting. This year's largest challenge was the location of the event. In the past two years IndyTechFest was held at the Gene B. Glick Junior Achievement Center in Indianapolis. This facility has been the hub of the Indy technical community for many years. As the big day drew near, the facility's availability came into question due to some recent changes that had occurred with those who operated the facility. We began our search for an alternative option. Thankfully, the Marriott Indianapolis East was available, was very spacious and willing to work within the range of our budget. Within days of our event, the decision to move proved to be wise since the prior location had begun renovations to the interior. Whew! Always trust your gut. Every day it's getting better At the ending of each year, we huddle together, review the evaluations and identify an area in which the event could improve. This year's big opportunity for improvement resided in the prize give-away portion at the end of the day. In the 2008 event, admittedly, this portion was rather chaotic, rushed and disorganized. This year, we broke the drawing into two sections, of which each attendee received two tickets. The first ticket was a drawing for the mountain of books that were given away. The second ticket was a drawing for the big prizes, the 2 Xboxes, 3 laptops and iPad. We peppered the ticket drawings with gift card raffles and tossing t-shirts into the audience. If at first you don't succeed, try and try again Each year of IndyTechFest, we have offered a means for ad-hoc sessions or discussion groups to pop-up. To our disappointment it was something that never quite took off. We have always believed that this unique type of session was valuable and wanted to figure out a way to make it work for this year. A special thanks to Alan Stevens, who took on and facilitated the "open space" track and made it an official success. Share with your tweety When the attendee badges were designed we decided to place an emphasis on the attendee's Twitter account as well as the events hash-tag (#IndyTechFest) to encourage some real-time buzz during the day. At the host table we displayed a Twitter feed for all to enjoy. It was quite successful and encouraging use of social media. My badge was missing my Twitter account since it was recently changed. For those who care to follow my rather sparse tweets, my address is @johnnydata. Man, this is one long blog post! All in all it was a very successful event. It is always great to see new faces and meet old friends. The planning for the 2011 IndyTechFest will kick off very soon. We have more capacity for future growth and a truck full of great ideas. Stay tuned!

    Read the article

  • What's New In 11.1.2.1 (Talleyrand SP1)

    - by russ.bishop
    This release is primarily about bug fixes and that's what we spent the most time on, but we also addressed a number of other things: 1. Performance improvements We've done a lot of work to improve the performance of page load and execution times. For example, the View Compare page is about half the size it was previously! We've also done a lot of work on the server to improve performance of queries, exports, action scripts, etc. We implemented some finer-grained locking so fewer operations will block other users while they are in progress. We made some optimizations to improve performance when you have a lot of network or database latency as well. Just a few examples: An Import that previously took 8 GB of memory and hours to complete now runs in about 30 minutes and never takes more than 1 GB of RAM. Searching by exact Node Name now completes within 2 seconds even for a hierarchy with millions of nodes. Another search that was taking 30 seconds to run now completes in less than 5 seconds. 2. Upgrade support This release supports automatic upgrade from previous releases, built right into the console. 3. Console Improvements The Console has been reorganized and made easier to use. It is also much more multi-threaded so it responds quicker without freezing up when you save changes or when it needs to get status. 4. Property Namespaces Properties now have a concept called a Namespace. This is tied into the Application Templates to prevent conflicts with duplicate property names. Right now, if you have an AccountType and you pull in the HFM template, it also has AccountType so you end up creating properties with decorations on the name like "Account Type (HFM)". This is no longer necessary. In addition, properties within a namespace must have unique labels but they can be duplicated across namespaces. So in the Property Grid when you click on the HFM category, you just see "AccountType". When you click on MyCategory, you see "AccountType", but they are different properties with different values. Within formulas, the names are still unique (eg: Custom.AccountType vs HFM.AccountType). I'll write more about this one later. 5. Single Sign On DRM now supports Single Sign-On via HSS. For example, if you are using Oracle's OAM as your SSO solution then you configure HSS to use OAM just like you would before. You also configure DRM to use HSS, again just like before. Then you configure OAM to protect the DRM web app, like you would any other website. However once you do those things, users are no longer prompted to enter their username/password. They simply get redirected to OAM if they don't already have a login token, otherwise they pick their application and sail right into DRM. You can also avoid having to pick an application (see the next item) 6. URL-based navigation You can now specify the application you want to log into via the URL. Combined with SSO and your Intranet, it becomes easy to provide links on our intranet portal that take users directly into a specific DRM application. We also support specifying the Version, Hierarchy, and Node. Again, this can be used on your internal portal, but the scenarios get even more interesting when you are using workflow like Oracle BPEL you can automatically generate links within emails that will take users directly to a specific node in the UI. 7. Job status and cancellation A lot of the jobs now report their status and support true cancellation. Action Scripts also report a progress complete percentage since the amount of work is known ahead of time. 8. Action Script Options Action scripts support Option declarations at the top of the file so a script can self-describe (when specified in the file, the corresponding item in the file is ignored). For example: Option|DetectDelimiter Option|UsePropertyNames|true This will tell DRM to automatically detect the delimiter (a pipe symbol in this case) and that all references to properties are by Name, not by Label. Note that when you load a script in the UI, if you use Labels we automatically try to match them up if they are unique. Any duplicates are indicated and you are presented with a choice to pick which property you actually referred to. This is somewhat similar to Version substitution, but tailored for properties. There are other more minor changes and like I said earlier a lot of bug fixes and performance improvements. Hopefully I will get a chance to dig into some of these things in future blog posts.

    Read the article

  • SQL SERVER – Weekly Series – Memory Lane – #053 – Final Post in Series

    - by Pinal Dave
    It has been a fantastic journey to write memory lane series for an entire year. This series gave me the opportunity to go back and see what I have contributed to this blog throughout the last 7 years. This was indeed fantastic series as this provided me the opportunity to witness how technology has grown throughout the year and how I have progressed in my career while writing this blog post. This series was indeed fantastic experience readers as many joined during the last few years and were not sure what they have missed in recent years. Let us continue with the final episode of the Memory Lane Series. Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 Get Current User – Get Logged In User Here is the straight script which list logged in SQL Server users. Disable All Triggers on a Database – Disable All Triggers on All Servers Question : How to disable all the triggers for a database? Additionally, how to disable all the triggers for all servers? For answer execute the script in the blog post. Importance of Master Database for SQL Server Startup I have received following questions many times. I will list all the questions here and answer them together. What is the purpose of Master database? Should our backup Master database? Which database is must have database for SQL Server for startup? Which are the default system database created when SQL Server 2005 is installed for the first time? What happens if Master database is corrupted? Answers to all of the questions are very much related. 2008 DECLARE Multiple Variables in One Statement SQL Server is a great product and it has many features which are very unique to SQL Server. Regarding feature of SQL Server where multiple variable can be declared in one statement, it is absolutely possible to do. 2009 How to Enable Index – How to Disable Index – Incorrect syntax near ‘ENABLE’ Many times I have seen that the index is disabled when there is a large update operation on the table. Bulk insert of very large file updates in any table using SSIS is usually preceded by disabling the index and followed by enabling the index. I have seen many developers running the following query to disable the index. 2010 List of all the Views from Database Many emails I received suggesting that they have hundreds of the view and now have no clue what is going on and how many of them have indexes and how many does not have an index. Some even asked me if there is any way they can get a list of the views with the property of Index along with it. Here is the quick script which does exactly the same. You can also include many other columns from the same view. Minimum Maximum Memory – Server Memory Options I was recently reading about SQL Server Memory Options over here. While reading this one line really caught my attention is minimum value allowed for maximum memory options. The default setting for min server memory is 0, and the default setting for max server memory is 2147483647. The minimum amount of memory you can specify for max server memory is 16 megabytes (MB). 2011 Fundamentals of Columnstore Index There are two kinds of storage in a database. Row Store and Column Store. Row store does exactly as the name suggests – stores rows of data on a page – and column store stores all the data in a column on the same page. These columns are much easier to search – instead of a query searching all the data in an entire row whether the data are relevant or not, column store queries need only to search a much lesser number of the columns. How to Ignore Columnstore Index Usage in Query In summary the question in simple words “How can we ignore using the column store index in selective queries?” Very interesting question – you can use I can understand there may be the cases when the column store index is not ideal and needs to be ignored the same. You can use the query hint IGNORE_NONCLUSTERED_COLUMNSTORE_INDEX to ignore the column store index. The SQL Server Engine will use any other index which is best after ignoring the column store index. 2012 Storing Variable Values in Temporary Array or Temporary List SQL Server does not support arrays or a dynamic length storage mechanism like list. Absolutely there are some clever workarounds and few extra-ordinary solutions but everybody can;t come up with such solution. Additionally, sometime the requirements are very simple that doing extraordinary coding is not required. Here is the simple case. Move Database Files MDF and LDF to Another Location It is not common to keep the Database on the same location where OS is installed. Usually Database files are in SAN, Separate Disk Array or on SSDs. This is done usually for performance reason and manageability perspective. Now the challenges comes up when database which was installed at not preferred default location and needs to move to a different location. Here is the quick tutorial how you can do it. UNION ALL and ORDER BY – How to Order Table Separately While Using UNION ALL If your requirement is such that you want your top and bottom query of the UNION resultset independently sorted but in the same result set you can add an additional static column and order by that column. Let us re-create the same scenario. Copy Data from One Table to Another Table – SQL in Sixty Seconds #031 – Video http://www.youtube.com/watch?v=FVWIA-ACMNo Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

    Read the article

  • High Jinks, Hi Jacks, Exceptional DBA Awards and PASS

    - by Rodney
    The countdown to PASS has counted down.  The day after tomorrow I will board a plane, like many others, on my way for the 4th year in a row to SQL PASS Summit.  The anticipation has been excruciating but luckily I have this little thing called a day job as a DBA that has kept me busy and not thinking too much about the event. Well that is not exactly true since my beautiful wife works for PASS so we get to talk about SQL from the time we wake up until late in the evening. I would not have it any other way and I feel very fortunate to be a part of this great event and to have been chosen as the Exceptional DBA Award judge also for the 4th year in a row.  This year, I will have been again tasked with presenting the award to the winner, Mr. Jeff Moden and it will be a true honor to meet him in person as I have read many of his articles on SSC and have attended his session at PASS previously.  The speech is all ready but one item remains, which will be a surprise to all who attend the party on Tuesday night in Seattle (see links below).  Let's face it, Exceptional DBAs everywhere work very hard protecting our data stores, tuning queries, mentoring, saving money, installing clusters, etc and once in a while there is time to be exceptionally non-professional and have a bit of fun. Once incident that happened this year that falls under the High Jinks category was when my network admin asked if I could Telnet into a SQL instance and see if I could make the connection through the firewall that he had just configured. I was able to establish a connection on port 1433 and it occurred to me that it would be very interesting if I could actually run T-SQL queries via a Telnet session much like you might do with an SMTP server. With that thought, I proceeded to demonstrate this could be possible by convincing my senior DBA Shawn McGehee that I was able to do so. At first he did not believe me. It shook his world view.  It was inconceivable.  What I had done, behind the scenes, of course, was to copy and rename SQLCMD.exe to Telnet.exe and used it to connect and run a simple, "Select * from sys.databases" on the SQL instance. I think if it had been anyone other than Shawn I could have extended this ruse indefinitely but he caught on within 30 seconds. It was a fun thirty seconds though. On the High Jacks side of the house, which is really merged to be SQL HACKS, I finally, after several years of struggling with how to connect to an untrusted domain like in a DMZ with a windows account in SSMS, I stumbled upon a solution that does away with the requirement to use SQL Authentication.  While "Runas" is a great command to use to run an application with a higher privileged account, I had not previously been able to figure out how to connect to the remote domain with SSMS and "Runsas". It never connected and caused a login failure every time for the remote windows domain account. Then I ran across an option for "Runas",   "/netonly".  This option postpones the login until a connection is made and only then passes the remote login you supply when you first launch SSMS with the "Runas" command. So a typical shortcut would look like: "C:\Windows\System32\runas.exe /netonly /user:remotedomain.com\rodlandrum "C:\Program Files\Microsoft SQL Server\100\Tools\Binn\VSShell\Common7\IDE\Ssms.exe" You will want to make sure the passwords are synced between the two domains, your local domain and the remote domain, otherwise you may have account lockout issues, but I have found in weeks of testing this is a stable solution. Now it is time to get ready to head for Seattle. Please, if you see me (@SQLBeat) or my wife (@Karlakay22) please run up and high five me (wait..High Jinks.High Jacks.High Fives.Need to change the title) or give me a big bear hug if you are strong enough to lift me off the ground. And if you do actually do that, I will think you are awesome and will not embarrass you by crying out for help or complaining of a broken back or sciatic nerve damage. And now the links to others who have all of the details. First, for the MVP Deep Dives 2, of which, like John, I was lucky enough to be able to participate in this year. http://www.simple-talk.com/community/blogs/johnm/archive/2011/09/29/103577.aspx And the details of the SSC party where the Exceptional DBA of 2011, Jeff Moden, will be awarded. http://www.simple-talk.com/community/blogs/rebecca_amos/archive/2011/10/05/103661.aspx   Cheers! Rodney

    Read the article

  • Imaging: Paper Paper Everywhere, but None Should be in Sight

    - by Kellsey Ruppel
    Author: Vikrant Korde, Technical Architect, Aurionpro's Oracle Implementation Services team My wedding photos are stored in several empty shoeboxes. Yes...I got married before digital photography was mainstream...which means I'm old. But my parents are really old. They have shoeboxes filled with vacation photos on slides (I doubt many of you have even seen a home slide projector...and I hope you never do!). Neither me nor my parents should have shoeboxes filled with any form of photographs whatsoever. They should obviously live in the digital world...with no physical versions in sight (other than a few framed on our walls). Businesses grapple with similar challenges. But instead of shoeboxes, they have file cabinets and warehouses jam packed with paper invoices, legal documents, human resource files, material safety data sheets, incident reports, and the list goes on and on. In fact, regulatory and compliance rules govern many industries, requiring that this paperwork is available for any number of years. It's a real challenge...especially trying to find archived documents quickly and many times with no backup. Which brings us to a set of technologies called Image Process Management (or simply Imaging or Image Processing) that are transforming these antiquated, paper-based processes. Oracle's WebCenter Content Imaging solution is a combination of their WebCenter suite, which offers a robust set of content and document management features, and their Business Process Management (BPM) suite, which helps to automate business processes through the definition of workflows and business rules. Overall, the solution provides an enterprise-class platform for end-to-end management of document images within transactional business processes. It's a solution that provides all of the capabilities needed - from document capture and recognition, to imaging and workflow - to effectively transform your ‘shoeboxes’ of files into digitally managed assets that comply with strict industry regulations. The terminology can be quite overwhelming if you're new to the space, so we've provided a summary of the primary components of the solution below, along with a short description of the two paths that can be executed to load images of scanned documents into Oracle's WebCenter suite. WebCenter Imaging (WCI): the electronic document repository that provides security, annotations, and search capabilities, and is the primary user interface for managing work items in the imaging solution SOA & BPM Suites (workflow): provide business process management capabilities, including human tasks, workflow management, service integration, and all other standard SOA features. It's interesting to note that there a number of 'jumpstart' processes available to help accelerate the integration of business applications, such as the accounts payable invoice processing solution for E-Business Suite that facilitates the processing of large volumes of invoices WebCenter Enterprise Capture (WEC): expedites the capture process of paper documents to digital images, offering high volume scanning and importing from email, and allows for flexible indexing options WebCenter Forms Recognition (WFR): automatically recognizes, categorizes, and extracts information from paper documents with greatly reduced human intervention WebCenter Content: the backend content server that provides versioning, security, and content storage There are two paths that can be executed to send data from WebCenter Capture to WebCenter Imaging, both of which are described below: 1. Direct Flow - This is the simplest and quickest way to push an image scanned from WebCenter Enterprise Capture (WEC) to WebCenter Imaging (WCI), using the bare minimum metadata. The WEC activities are defined below: The paper document is scanned (or imported from email). The scanned image is indexed using a predefined indexing profile. The image is committed directly into the process flow 2. WFR (WebCenter Forms Recognition) Flow - This is the more complex process, during which data is extracted from the image using a series of operations including Optical Character Recognition (OCR), Classification, Extraction, and Export. This process creates three files (Tiff, XML, and TXT), which are fed to the WCI Input Agent (the high speed import/filing module). The WCI Input Agent directory is a standard ingestion method for adding content to WebCenter Imaging, the process for doing so is described below: WEC commits the batch using the respective commit profile. A TIFF file is created, passing data through the file name by including values separated by "_" (underscores). WFR completes OCR, classification, extraction, export, and pulls the data from the image. In addition to the TIFF file, which contains the document image, an XML file containing the extracted data, and a TXT file containing the metadata that will be filled in WCI, are also created. All three files are exported to WCI's Input agent directory. Based on previously defined "input masks", the WCI Input Agent will pick up the seeding file (often the TXT file). Finally, the TIFF file is pushed in UCM and a unique web-viewable URL is created. Based on the mapping data read from the TXT file, a new record is created in the WCI application.  Although these processes may seem complex, each Oracle component works seamlessly together to achieve a high performing and scalable platform. The solution has been field tested at some of the largest enterprises in the world and has transformed millions and millions of paper-based documents to more easily manageable digital assets. For more information on how an Imaging solution can help your business, please contact [email protected] (for U.S. West inquiries) or [email protected] (for U.S. East inquiries). About the Author: Vikrant is a Technical Architect in Aurionpro's Oracle Implementation Services team, where he delivers WebCenter-based Content and Imaging solutions to Fortune 1000 clients. With more than twelve years of experience designing, developing, and implementing Java-based software solutions, Vikrant was one of the founding members of Aurionpro's WebCenter-based offshore delivery team. He can be reached at [email protected].

    Read the article

  • Breaking through the class sealing

    - by Jason Crease
    Do you understand 'sealing' in C#?  Somewhat?  Anyway, here's the lowdown. I've done this article from a C# perspective, but I've occasionally referenced .NET when appropriate. What is sealing a class? By sealing a class in C#, you ensure that you ensure that no class can be derived from that class.  You do this by simply adding the word 'sealed' to a class definition: public sealed class Dog {} Now writing something like " public sealed class Hamster: Dog {} " you'll get a compile error like this: 'Hamster: cannot derive from sealed type 'Dog' If you look in an IL disassembler, you'll see a definition like this: .class public auto ansi sealed beforefieldinit Dog extends [mscorlib]System.Object Note the addition of the word 'sealed'. What about sealing methods? You can also seal overriding methods.  By adding the word 'sealed', you ensure that the method cannot be overridden in a derived class.  Consider the following code: public class Dog : Mammal { public sealed override void Go() { } } public class Mammal { public virtual void Go() { } } In this code, the method 'Go' in Dog is sealed.  It cannot be overridden in a subclass.  Writing this would cause a compile error: public class Dachshund : Dog { public override void Go() { } } However, we can 'new' a method with the same name.  This is essentially a new method; distinct from the 'Go' in the subclass: public class Terrier : Dog { public new void Go() { } } Sealing properties? You can also seal seal properties.  You add 'sealed' to the property definition, like so: public sealed override string Name {     get { return m_Name; }     set { m_Name = value; } } In C#, you can only seal a property, not the underlying setters/getters.  This is because C# offers no override syntax for setters or getters.  However, in underlying IL you seal the setter and getter methods individually - a property is just metadata. Why bother sealing? There are a few traditional reasons to seal: Invariance. Other people may want to derive from your class, even though your implementation may make successful derivation near-impossible.  There may be twisted, hacky logic that could never be second-guessed by another developer.  By sealing your class, you're protecting them from wasting their time.  The CLR team has sealed most of the framework classes, and I assume they did this for this reason. Security.  By deriving from your type, an attacker may gain access to functionality that enables him to hack your system.  I consider this a very weak security precaution. Speed.  If a class is sealed, then .NET doesn't need to consult the virtual-function-call table to find the actual type, since it knows that no derived type can exist.  Therefore, it could emit a 'call' instead of 'callvirt' or at least optimise the machine code, thus producing a performance benefit.  But I've done trials, and have been unable to demonstrate this If you have an example, please share! All in all, I'm not convinced that sealing is interesting or important.  Anyway, moving-on... What is automatically sealed? Value types and structs.  If they were not always sealed, all sorts of things would go wrong.  For instance, structs are laid-out inline within a class.  But what if you assigned a substruct to a struct field of that class?  There may be too many fields to fit. Static classes.  Static classes exist in C# but not .NET.  The C# compiler compiles a static class into an 'abstract sealed' class.  So static classes are already sealed in C#. Enumerations.  The CLR does not track the types of enumerations - it treats them as simple value types.  Hence, polymorphism would not work. What cannot be sealed? Interfaces.  Interfaces exist to be implemented, so sealing to prevent implementation is dumb.  But what if you could prevent interfaces from being extended (i.e. ban declarations like "public interface IMyInterface : ISealedInterface")?  There is no good reason to seal an interface like this.  Sealing finalizes behaviour, but interfaces have no intrinsic behaviour to finalize Abstract classes.  In IL you can create an abstract sealed class.  But C# syntax for this already exists - declaring a class as a 'static', so it forces you to declare it as such. Non-override methods.  If a method isn't declared as override it cannot be overridden, so sealing would make no difference.  Note this is stated from a C# perspective - the words are opposite in IL.  In IL, you have four choices in total: no declaration (which actually seals the method), 'virtual' (called 'override' in C#), 'sealed virtual' ('sealed override' in C#) and 'newslot virtual' ('new virtual' or 'virtual' in C#, depending on whether the method already exists in a base class). Methods that implement interface methods.  Methods that implement an interface method must be virtual, so cannot be sealed. Fields.  A field cannot be overridden, only hidden (using the 'new' keyword in C#), so sealing would make no sense.

    Read the article

  • Why enumerator structs are a really bad idea

    - by Simon Cooper
    If you've ever poked around the .NET class libraries in Reflector, I'm sure you would have noticed that the generic collection classes all have implementations of their IEnumerator as a struct rather than a class. As you will see, this design decision has some rather unfortunate side effects... As is generally known in the .NET world, mutable structs are a Very Bad Idea; and there are several other blogs around explaining this (Eric Lippert's blog post explains the problem quite well). In the BCL, the generic collection enumerators are all mutable structs, as they need to keep track of where they are in the collection. This bit me quite hard when I was coding a wrapper around a LinkedList<int>.Enumerator. It boils down to this code: sealed class EnumeratorWrapper : IEnumerator<int> { private readonly LinkedList<int>.Enumerator m_Enumerator; public EnumeratorWrapper(LinkedList<int> linkedList) { m_Enumerator = linkedList.GetEnumerator(); } public int Current { get { return m_Enumerator.Current; } } object System.Collections.IEnumerator.Current { get { return Current; } } public bool MoveNext() { return m_Enumerator.MoveNext(); } public void Reset() { ((System.Collections.IEnumerator)m_Enumerator).Reset(); } public void Dispose() { m_Enumerator.Dispose(); } } The key line here is the MoveNext method. When I initially coded this, I thought that the call to m_Enumerator.MoveNext() would alter the enumerator state in the m_Enumerator class variable and so the enumeration would proceed in an orderly fashion through the collection. However, when I ran this code it went into an infinite loop - the m_Enumerator.MoveNext() call wasn't actually changing the state in the m_Enumerator variable at all, and my code was looping forever on the first collection element. It was only after disassembling that method that I found out what was going on The MoveNext method above results in the following IL: .method public hidebysig newslot virtual final instance bool MoveNext() cil managed { .maxstack 1 .locals init ( [0] bool CS$1$0000, [1] valuetype [System]System.Collections.Generic.LinkedList`1/Enumerator CS$0$0001) L_0000: nop L_0001: ldarg.0 L_0002: ldfld valuetype [System]System.Collections.Generic.LinkedList`1/Enumerator EnumeratorWrapper::m_Enumerator L_0007: stloc.1 L_0008: ldloca.s CS$0$0001 L_000a: call instance bool [System]System.Collections.Generic.LinkedList`1/Enumerator::MoveNext() L_000f: stloc.0 L_0010: br.s L_0012 L_0012: ldloc.0 L_0013: ret } Here, the important line is 0002 - m_Enumerator is accessed using the ldfld operator, which does the following: Finds the value of a field in the object whose reference is currently on the evaluation stack. So, what the MoveNext method is doing is the following: public bool MoveNext() { LinkedList<int>.Enumerator CS$0$0001 = this.m_Enumerator; bool CS$1$0000 = CS$0$0001.MoveNext(); return CS$1$0000; } The enumerator instance being modified by the call to MoveNext is the one stored in the CS$0$0001 variable on the stack, and not the one in the EnumeratorWrapper class instance. Hence why the state of m_Enumerator wasn't getting updated. Hmm, ok. Well, why is it doing this? If you have a read of Eric Lippert's blog post about this issue, you'll notice he quotes a few sections of the C# spec. In particular, 7.5.4: ...if the field is readonly and the reference occurs outside an instance constructor of the class in which the field is declared, then the result is a value, namely the value of the field I in the object referenced by E. And my m_Enumerator field is readonly! Indeed, if I remove the readonly from the class variable then the problem goes away, and the code works as expected. The IL confirms this: .method public hidebysig newslot virtual final instance bool MoveNext() cil managed { .maxstack 1 .locals init ( [0] bool CS$1$0000) L_0000: nop L_0001: ldarg.0 L_0002: ldflda valuetype [System]System.Collections.Generic.LinkedList`1/Enumerator EnumeratorWrapper::m_Enumerator L_0007: call instance bool [System]System.Collections.Generic.LinkedList`1/Enumerator::MoveNext() L_000c: stloc.0 L_000d: br.s L_000f L_000f: ldloc.0 L_0010: ret } Notice on line 0002, instead of the ldfld we had before, we've got a ldflda, which does this: Finds the address of a field in the object whose reference is currently on the evaluation stack. Instead of loading the value, we're loading the address of the m_Enumerator field. So now the call to MoveNext modifies the enumerator stored in the class rather than on the stack, and everything works as expected. Previously, I had thought enumerator structs were an odd but interesting feature of the BCL that I had used in the past to do linked list slices. However, effects like this only underline how dangerous mutable structs are, and I'm at a loss to explain why the enumerators were implemented as structs in the first place. (interestingly, the SortedList<TKey, TValue> enumerator is a struct but is private, which makes it even more odd - the only way it can be accessed is as a boxed IEnumerator!). I would love to hear people's theories as to why the enumerators are implemented in such a fashion. And bonus points if you can explain why LinkedList<int>.Enumerator.Reset is an explicit implementation but Dispose is implicit... Note to self: never ever ever code a mutable struct.

    Read the article

  • SQL SERVER – Not Possible – Delete From Multiple Table – Update Multiple Table in Single Statement

    - by pinaldave
    There are two questions which I get every single day multiple times. In my gmail, I have created standard canned reply for them. Let us see the questions here. I want to delete from multiple table in a single statement how will I do it? I want to update multiple table in a single statement how will I do it? The answer is – No, You cannot and you should not. SQL Server does not support deleting or updating from two tables in a single update. If you want to delete or update two different tables – you may want to write two different delete or update statements for it. This method has many issues – from the consistency of the data to SQL syntax. Now here is the real reason for this blog post – yesterday I was asked this question again and I replied my canned answer saying it is not possible and it should not be any way implemented that day. In the response to my reply I was pointed out to my own blog post where user suggested that I had previously mentioned this is possible and with demo example. Let us go over my conversation – you may find it interesting. Let us call the user DJ. DJ: Pinal, can we delete multiple table in a single statement or with single delete statement? Pinal: No, you cannot and you should not. DJ: Oh okey, if that is the case, why do you suggest to do that? Pinal: (baffled) I am not suggesting that. I am rather suggesting that it is not possible and it should not be possible. DJ: Hmm… but in that case why did you blog about it earlier? Pinal: (What?) No, I did not. I am pretty confident. DJ: Well, I am confident as well. You did. Pinal: In that case, it is my word against your word. Isn’t it? DJ: I have proof. Do you want to see it that you suggest it is possible? Pinal: Yes, I will be delighted too. (After 10 Minutes) DJ: Here are not one but two of your blog posts which talks about it - SQL SERVER – Curious Case of Disappearing Rows – ON UPDATE CASCADE and ON DELETE CASCADE – Part 1 of 2 SQL SERVER – Curious Case of Disappearing Rows – ON UPDATE CASCADE and ON DELETE CASCADE – T-SQL Example – Part 2 of 2 Pinal: Oh! DJ: I know I was correct. Pinal: Well, oh man, I did not mean there what you mean here. DJ: I did not understand can you explain it further. Pinal: Here we go. The example in the other blog is the example of the cascading delete or cascading update. I think you may want to understand the concept of the foreign keys and cascading update/delete. The concept of cascading exists to maintain data integrity. If there primary keys get deleted the update or delete reflects on the foreign key table to maintain the key integrity and data consistency. SQL Server follows ANSI Entry SQL with regard to referential integrity between PrimaryKey and ForeignKey columns which requires the inserting, updating, and deleting of data in related tables to be restricted to values that preserve the integrity. This is all together different concept than deleting multiple values in a single statement. When I hear that someone wants to delete or update multiple table in a single statement what I assume is something very similar to following. DELETE/UPDATE Table 1 (cols) Table 2 (cols) VALUES … which is not valid statement/syntax as well it is not ASNI standards as well. I guess, after this discussion with DJ, I realize I need to do a blog post so I can add the link to this blog post in my canned answer. Well, it was a fun conversation with DJ and I hope it the message is very clear now. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Joins, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

    Read the article

  • Highlights from the Oracle Customer Experience Summit @ OpenWorld

    - by Kathryn Perry
    A guest post by David Vap, Group Vice President, Oracle Applications Product Development The Oracle Customer Experience Summit was the first-ever event covering the full breadth of Oracle's CX portfolio -- Marketing, Sales, Commerce, and Service. The purpose of the Summit was to articulate the customer experience imperative and to showcase the suite of Oracle products that can help our customers create the best possible customer experience. This topic has always been a very important one, but now that there are so many alternative companies to do business with and because people have such public ways to voice their displeasure, it's necessary for vendors to have multiple listening posts in place to gauge consumer sentiment. They need to know what is going on in real time and be able to react quickly to turn negative situations into positive ones. Those can then be shared in a social manner to enhance the brand and turn the customer into a repeat customer. The Summit was focused on Oracle's portfolio of products and entirely dedicated to customers who are committed to building great customer experiences within their businesses. Rather than DBAs, the attendees were business people looking to collaborate with other like-minded experts and find out how Oracle can help in terms of technology, best practices, and expertise. The event was at the Westin St. Francis Hotel in San Francisco as part of Oracle OpenWorld. We had eight hundred people attend, which was great for the first year. Next year, there's no doubt in my mind, we can raise that number to 5,000. Alignment and Logic Oracle's Customer Experience portfolio is made up of a combination of acquired and organic products owned by many people who are new to Oracle. We include homegrown Fusion CRM, as well as RightNow, Inquira, OPA, Vitrue, ATG, Endeca, and many others. The attendees knew of the acquisitions, so naturally they wanted to see how the products all fit together and hear the logic behind the portfolio. To tell them about our alignment, we needed to be aligned. To accomplish that, a cross functional team at Oracle agreed on the messaging so that every single Oracle presenter could cover the big picture before going deep into a product or topic. Talking about the full suite of products in one session produced overflow value for other products. And even though this internal coordination was a huge effort, everyone saw the value for our customers and for our long-term cooperation and success. Keynotes, Workshops, and Tents of Innovation We scored by having Seth Godin as our keynote speaker ? always provocative and popular. The opening keynote was a session orchestrated by Mark Hurd, Anthony Lye, and me. Mark set the stage by giving real-world examples of bad customer experiences, Anthony clearly articulated the business imperative for addressing these experiences, and I brought it all to life by taking the audience around the Customer Lifecycle and showing demos and videos, with partners included at each of the stops around the lifecycle. Brian Curran, a VP for RightNow Product Strategy, presented a session that was in high demand called The Economics of Customer Experience. People loved hearing how to build a business case and justify the cost of building a better customer experience. John Kembel, another VP for RightNow Product Strategy, held a workshop that customers raved about. It was based on the journey mapping methodology he created, which is a way to talk to customers about where they want to make improvements to their customers' experiences. He divided the audience into groups led by facilitators. Each person had the opportunity to engage with experts and peers and construct some real takeaways. From left to right: Brian Curran, John Kembel, Seth Godin, and George Kembel The conference hotel was across from Union Square so we used that space to set up Innovation Tents. During the day we served lunch in the tents and partners showed their different innovative ideas. It was very interesting to see all the technologies and advancements. It also gave people a place to mix and mingle and to think about the fringe of where we could all take these ideas. Product Portfolio Plus Thought Leadership Of course there is always room for improvement, but the feedback on the format of the conference was positive. Ninety percent of the sessions had either a partner or a customer teamed with an Oracle presenter. The presentations weren't dry, one-way information dumps, but more interactive. I just followed up with a CEO who attended the conference with his Head of Marketing. He told me that they are using John Kembel's journey mapping methodology across the organization to pull people together. This sort of thought leadership in these highly competitive areas gives Oracle permission to engage around the technology. We have to differentiate ourselves and it's harder to do on the product side because everyone looks the same on paper. But on thought leadership ? we can, and did, take some really big steps. David VapGroup Vice PresidentOracle Applications Product Development

    Read the article

  • Come meet our Interns in Dublin

    - by klaudia.drulis
    Oracle Worldwide Product Translation Group (WPTG) provides solutions for all Oracle product and Content translation requirements. WPTG is a global organisation with its headquarters in Ireland and employees in Oracle offices worldwide. WPTG offer expertise in fields such as process engineering, tools development, linguistic quality, terminology, global product release, financial and vendor management. WPTG provides translation solution for over 40 languages including Asia Pacific, European, American and Middle Eastern languages. WPTG first introduced an intern program over 10 years ago and it has become a key component of our teams structure. The majority of Interns are sourced from a Computer Science related course, these Interns joining the engineering team. Others are sourced from Business courses and work within the Business / Project management area. The intern program allows us to maintain ties with current course curriculum and brings fresh energy and perspective into our Organisation. Four of the full time staff working in Dublin today joined us originally as Interns and subsequently were offered permanent positions. Come Meet some of our 2010 Interns, Come and see what Darragh, Anthony, Caoimhe, James and Artemij thought about working within the WPTG at Oracle: Darragh “Oracle has been a fun, challenging work placement for me. From day one I was treated as a full member of staff, this was both comforting and a little bit scary. The responsibilities stack up but I found I was able to keep on top of everything and even make improvements to how we handle a few things thanks to a great team and a very supportive manager. There’s a very positive atmosphere in work that’s really conducive to getting a lot of work done. Ideas seem to be the central hub in my line of business so all of my ideas and innovations were greeted with enthusiasm. Oracle has given me a fantastic opportunity and I urge you to grab it with both hands, you’ll find that you’re with a set of like minded people from all works of life that make work both interesting and fun. Even when the pressure is on you know that you can always get help and advice from someone nearby. My last word of advice is don’t be afraid to stick your neck out, everyone here is willing to learn, try something new and innovate, your voice will be heard and who knows, you could end up having a large impact on Oracle and your career.” Anthony “I had a great experience working with Oracle, from day one I was treated like a full member of staff with responsibilities of my own. I found that the more I put into the work the more I got out from the experience. Volunteering and being willing to face challenges have made this a more exciting placement. I am given a lot of leeway to do my own projects and so I’ve found that I am really enjoying my time here.” Caoimhe “I am currently spending my year of placement within the Release Management Team in the WPTG. My main role is to handle the finance process of all translation projects under 100k which includes creating workspecs and PO's, sending out kits, dealing with vendor queries and handling the invoicing and payment part. I am really enjoying my time here at Oracle, everyone is very open and friendly and willing to help you out with any questions you may have. I would definitely be interested in returning to Oracle after I graduate!” James “I am currently on a 12 month placement with Oracle, working as part of the Worldwide Product Translation Group in the Business Management. The Business Management team provides a global view on WPTG’s vendor and business strategy and is an interface into WPTG for new business. The business management team work together to support the external translation partner network. My role is to support the Business Management team and also to work on various projects when the need arises. This involves working with translation vendors and working with other Oracle employees worldwide. I am really enjoying my time working for Oracle, at times it can be challenging bit also very rewarding. I would recommend any student wanting to undertake a placement year to apply to Oracle, I made some great friends and I will never forget my time in Dublin.” Artemij “From working within Oracle, I have truly understood what "career path" is, and what opportunities a large corporation like Oracle can offer. Without any illusions, the work itself is exciting, sometimes challenging, tests your ability to handle pressure, to make decisions and take responsibility, to learn quickly and cooperate efficiently in order to solve a problem. I have learned a lot about myself. What I am good at, where and what I can do better. My placement at Oracle has allowed me to get a clearer picture of what I want, and which door I am going to open after college. If you have any questions related to this article feel free to contact  [email protected].  You can find our job opportunities via http://campus.oracle.com

    Read the article

  • PASS: 2013 Summit Location

    - by Bill Graziano
    HQ recently posted a brief update on our search for a location for 2013.  It includes links to posts by four Board members and two community members. I’d like to add my thoughts to the mix and ask you a question.  But I can’t give you a real understanding without telling you some history first. So far we’ve had the Summit in Chicago, San Francisco, Orlando, Dallas, Denver and Seattle.  Each has a little different feel and distinct memories.  I enjoyed getting drinks by the pool in Orlando after the sessions ended.  I didn’t like that our location in Dallas was so far away from all the nightlife.  Denver was in downtown but we had real challenges with hotels.  I enjoyed the different locations.  I always enjoyed the announcement during the third keynote with the location of the next Summit. There are two big events that impacted my thinking on the Summit location.  The first was our transition to the new management company in early 2007.  The event that September in Denver was put on with a six month planning cycle by a brand new headquarters staff.  It wasn’t perfect but came off much better than I had dared to hope.  It also moved us out of the cookie cutter conferences that we used to do into a model where we have a lot more control.  I think you’ll all agree that the production values of our last few Summits have been fantastic.  That Summit also led to our changing relationship with Microsoft.  Microsoft holds two seats on the PASS Board.  All the PASS Board members face the same challenge: we all have full-time jobs and PASS comes in second place professionally (or sometimes further back).  Starting in 2008 we were assigned a liaison from Microsoft that had a much larger block of time to coordinate with us.  That changed everything between PASS and Microsoft.  Suddenly we were talking to product marketing, Microsoft PR, their event team, the Tech*Ed team, the education division, their user group team and their field sales team – locally and internationally.  We strengthened our relationship with CSS, SQLCAT and the engineering teams.  We had exposure at the executive level that we’d never had before.  And their level of participation at the Summit changed from under 100 people to 400-500 people.  I think those 400+ Microsoft employees have value at a conference on Microsoft SQL Server.  For the first time, Seattle had a real competitive advantage over other cities. I’m one that looked very hard at staying in Seattle for a long, long time.  I think those Microsoft engineers have value to our attendees.  I think the increased support that Microsoft can provide when we’re in Seattle has value to our attendees.  But that doesn’t tell the whole story.  There’s a significant (and vocal!) percentage of our membership that wants the Summit outside Seattle.  Post-2007 PASS doesn’t know what it’s like to have a Summit outside of Seattle.  I think until we have a Summit in another city we won’t really know the trade-offs. I think a model where we move every third or every other year is interesting.  But until we have another Summit outside Seattle and we can evaluate the logistics and how important it is to have depth and variety in our Microsoft participation we won’t really know. Another benefit that comes with a move is variety or diversity.  I learn more when I’m exposed to new things and new people.  I believe that moving the Summit will give a different set of people an opportunity to attend. Grant Fritchey writes “It seems that the board is leaning, extremely heavily, towards making it a permanent fixture in Seattle.”  I don’t believe that’s true.  I know there was discussion of that earlier but I don’t believe it’s true now. And that brings me to my question.  Do we announce the city now or do we wait until the 2012 Summit?  I’m happy to announce Seattle vs. not-Seattle as soon as we sign the contract.  But I’d like to leave the actual city announcement until the 2011 Summit.  I like the drama and mystery of it.  I also like that it doesn’t give you a reason to skip a Summit and wait for the next one if it’s closer or back in Seattle.  The other side of the coin is that your planning is easier if you know where it is.  What do you think?

    Read the article

  • Infiniband: a highperformance network fabric - Part I

    - by Karoly Vegh
    Introduction:At the OpenWorld this year I managed to chat with interesting people again - one of them answering Infiniband deepdive questions with ease by coffee turned out to be one of Oracle's IB engineers, Ted Kim, who actually actively participates in the Infiniband Trade Association and integrates Oracle solutions with this highspeed network. This is why I love attending OOW. He granted me an hour of his time to talk about IB. This post is mostly based on that tech interview.Start of the actual post: Traditionally datatransfer between servers and storage elements happens in networks with up to 10 gigabit/seconds or in SANs with up to 8 gbps fiberchannel connections. Happens. Well, data rather trickles through.But nowadays data amounts grow well over the TeraByte order of magnitude, and multisocket/multicore/multithread Servers hunger data that these transfer technologies just can't deliver fast enough, causing all CPUs of this world do one thing at the same speed - waiting for data. And once again, I/O is the bottleneck in computing. FC and Ethernet can't keep up. We have half-TB SSDs, dozens of TB RAM to store data to be modified in, but can't transfer it. Can't backup fast enough, can't replicate fast enough, can't synchronize fast enough, can't load fast enough. The bad news is, everyone is used to this, like back in the '80s everyone was used to start compile jobs and go for a coffee. Or on vacation. The good news is, there's an alternative. Not so-called "bleeding-edge" 8gbps, but (as of now) 56. Not layers of overhead, but low latency. And it is available now. It has been for a while, actually. Welcome to the world of Infiniband. Short history:Infiniband was born as a result of joint efforts of HPAQ, IBM, Intel, Sun and Microsoft. They planned to implement a next-generation I/O fabric, in the 90s. In the 2000s Infiniband (from now on: IB) was quite popular in the high-performance computing field, powering most of the top500 supercomputers. Then in the middle of the decade, Oracle realized its potential and used it as an interconnect backbone for the first Database Machine, the first Exadata. Since then, IB has been booming, Oracle utilizes and supports it in a large set of its HW products, it is the backbone of the famous Engineered Systems: Exadata, SPARC SuperCluster, Exalogic, OVCA and even the new DB backup/recovery box. You can also use it to make servers talk highspeed IP to eachother, or to a ZFS Storage Appliance. Following Oracle's lead, even IBM has jumped the wagon, and leverages IB in its PureFlex systems, their first InfiniBand Machines.IB Structural Overview: If you want to use IB in your servers, the first thing you will need is PCI cards, in IB terms Host Channel Adapters, or HCAs. Just like NICs for Ethernet, or HBAs for FC. In these you plug an IB cable, going to an IB switch providing connection to other IB HCAs. Of course you're going to need drivers for those in your OS. Yes, these are long-available for Solaris and Linux. Now, what protocols can you talk over IB? There's a range of choices. See, IB isn't accepting package loss like Ethernet does, and hence doesn't need to rely on TCP/IP as a workaround for resends. That is, you still can run IP over IB (IPoIB), and that is used in various cases for control functionality, but the datatransfer can run over more efficient protocols - like native IB. About PCI connectivity: IB cards, as you see are fast. They bring low latency, which is just as important as their bandwidth. Current IB cards run at 56 gbit/s. That is slightly more than double of the capacity of a PCI Gen2 slot (of ~25 gbit/s). And IB cards are equipped usually with two ports - that is, altogether you'd need 112 gbit/s PCI slots, to be able to utilize FDR IB cards in an active-active fashion. PCI Gen3 slots provide you with around ~50gbps. This is why the most IB cards are configured in an active-standby way if both ports are used. Once again the PCI slot is the bottleneck. Anyway, the new Oracle servers are equipped with Gen3 PCI slots, an the new IB HCAs support those too. Oracle utilizes the QDR HCAs, running at 40gbp/s brutto, which translates to a 32gbp/s net traffic due to the 10:8 signal-to-data information ratio. Consolidation techniques: Technology never stops to evolve. Mellanox is working on the 100 gbps (EDR) version already, which will be optical, since signal technology doesn't allow EDR to be copper. Also, I hear you say "100gbps? I will never use/need that much". Are you sure? Have you considered consolidation scenarios, where (for example with Oracle Virtual Network) you could consolidate your platform to a high densitiy virtualized solution providing many virtual 10gbps interfaces through that 100gbps? Technology never stops to evolve. I still remember when a 10mbps network was impressively fast. Back in those days, 16MB of RAM was a lot. Now we usually run servers with around 100.000 times more RAM. If network infrastrucure speends could grow as fast as main memory capacities, we'd have a different landscape now :) You can utilize SRIOV as well for consolidation. That is, if you run LDoms (aka Oracle VM Server for SPARC) you do not have to add physical IB cards to all your guest LDoms, and you do not need to run VIO devices through the hypervisor either (avoiding overhead). You can enable SRIOV on those IB cards, which practically virtualizes the PCI bus, and you can dedicate Physical- and Virtual Functions of the virtualized HCAs as native, physical HW devices to your guests. See Raghuram's excellent post explaining SRIOV. SRIOV for IB is supported since LDoms 3.1.  This post is getting lengthier, so I will rename it to Part I, and continue it in a second post. 

    Read the article

  • The Arab HEUG is now a reality, and other random thoughts

    - by user9147039
    I just returned from Doha, Qatar where the first of its kind HEUG (Higher Education User Group) meeting for institutions in the Middle East and North Africa was held at Qatar University and jointly hosted by Damman University from Saudi Arabia. Over 80 delegates attended including representation from education institutions in Oman, Saudi Arabia, Lebanon, and Qatar. There are many other regional HEUG organizations in place (in Australia/New Zealand, APAC, EMEA, as well as smaller regional HEUG’s in the Netherlands, South Africa, and in regions of the US), but it was truly an accomplishment to see this Middle East/North Africa group organize and launch their chapter with a meeting of this quality. To be known as the Arab HEUG going forward, I am excited about the prospects for sharing between the institutions and for the growth of Oracle solutions in the region. In particular the hosts for the event (Qatar University) did a masterful job with logistics and organization, and the quality of the event was a testament to their capabilities. Among the more interesting and enlightening presentations I attended were one from Dammam University on the lessons learned from their implementation of Campus Solutions and transition off of Banner, as well as the use by Qatar University E-business Suite for grants management (both pre-and post-award). The most notable fact coming from this latter presentation was the fit (89%) of e-Business Suite Grants to the university’s requirements. In a few weeks time we will be convening the 5th meeting of the Oracle Education & Research Industry Strategy Council in Redwood Shores (5th since my advent into my current role). The main topics of discussion will be around our Higher Education Applications Strategy for the future (including cloud approaches to ERP (HCM, Finance, and Student Information Systems), how some cases studies on the benefits of leveraging delivered functionality and extensibility in the software (versus customization). On the second day of the event we will turn our attention to Oracle in Research and also budgeting and planning in higher education. Both of these sessions will include significant participation from council members in the form of panel discussions. Our EVP’s for Systems (John Fowler) and for Global Cloud Services and North America application sales (Joanne Olson) will join us for the discussion. I recently read a couple of articles that were surprising to me. The first was from Inside Higher Ed on October 15 entitled, “As colleges prepare for major software upgrades, Kuali tries to woo them from corporate vendors.” It continues to disappointment that after all this time we are still debating whether it is better to build enterprise software through open or community source initiatives when fully functional, flexible, supported, and widely adopted options exist in the marketplace. Over a decade or more ago when these solutions were relatively immature and there was a great deal of turnover in the market I could appreciate the initiatives like Kuali. But let’s not kid ourselves – the real objective of this movement is to counter a perceived predatory commercial software industry. Again, when commercial solutions are deployed as written without significant customization, and standard business processes are adopted, the cost of these solutions (relative to the value delivered) is quite low, and certain much lower than the massive investment (and risk) in in-house developers to support a bespoke community source system. In this era of cost pressures in education and the need to refocus resources on teaching, learning, and research, I believe it’s bordering on irresponsible to continue to pursue open-source ERP. Many of the adopter’s total costs are staggering and have little to show for their efforts and expended resources. The second article was recently in the Chronicle of Higher Education and was entitled “’Big Data’ Is Bunk, Obama Campaign’s Tech Guru Tells University Leaders.” This one was so outrageous I almost don’t want to legitimize it by referencing it here. In the article the writer relays statements made by Harper Reed, President Obama’s former CTO for his 2012 re-election campaign, that big data solutions in education have no relevance and are akin to snake oil. He goes on to state that while he’s a fan of data-driven decision making in education, most of the necessary analysis can be accomplished in Excel spreadsheets. Yeah… right. This is exactly what ails education (higher education in particular). Dozens of shadow and siloed systems running on spreadsheets with limited-to-no enterprise wide initiatives to harness the data-rich environment that is a higher ed institution and transform the data into useable information. I’ll grant Mr. Reed that “Big Data” is overused and hackneyed, but imperatives like improving student success in higher education are classic big data problems that data-mining and predictive analytics can address. Further, higher ed need to be producing a massive amount more data scientists and analysts than are currently in the pipeline, to further this discipline and application of these tools to many many other problems across multiple industries.

    Read the article

  • SQLAuthority News – A Conversation with an Old Friend – Sri Sridharan

    - by pinaldave
    Sri Sridharan is my old friend and we often talk on GTalk. The subject varies from Life in India/USA, movies, musics, and of course SQL. We have our differences when we talk about food or movie but we always agree when we talk about SQL. Yesterday while chatting with him we talked about SQLPASS and the conversation lasted for a long time. Here is the conversation between us on GTalk. I have removed a few of the personal talks and formatted into paragraphs as GTalk often shows stuff out of formatting. Pinal: Sri, Congrats on running for the PASS BoD again. You were so close last year. What made you decide to run again this year? Sri: Thank you Pinal for your leadership in the PASS India Community and all the things you do out there. After coming so close last year, there was no doubt in my mind that I will run again. I was truly humbled by the support I got from the community. Growing up in India for over 25 years, you are brought up in a very competitive part of the world. Right from the pressure of staying in the top of the class from kindergarten to your graduation, the relentless push from your parents about studying and getting good grades (and nothing else matters), you land up essentially living in a pressure cooker. To survive that relentless pressure, you need to have a thick skin, ability to stand up for who you really are , what you want to accomplish and in the process stay true those values. I am striving for a greater cause, to make PASS an organization that can help people with their SQL Server careers, to make PASS relevant to its chapter members, to make PASS an organization that every SQL professional in the world wants to be connected with. Just because I did not get elected or appointed last year does not mean that these causes are not worth fighting. Giving up upon failing the first time is simply not in me. If I did that, what message would I send to those who voted for me? What message would I send to my kids? Pinal: As someone who has such strong roots in India, what can the Indian PASS Community expect from you? Sri: First of all, I think fostering a regional leadership is something PASS must encourage as part of its global growth plan. For PASS global being able to understand all the issues in a region of the world and make sound decisions will be a tough thing to do on a continuous basis. I expect people like you, chapter leaders, regional mentors, MVPs of the region start playing a bigger role in shaping the next generation of PASS. That is something I said in my campaign and I still stand by it. I would like to see growth in the number of chapters in India. The current count does not truly represent the full potential of that region. I was pretty thrilled to see the Bangalore SQLSaturday happen early this year. I would like to see more of SQLSaturday events, at least in the major metro cities. I know the issues in India are very different from the rest of the world. So the formula needs to be tweaked a little for it to work better in India. Once the SQLSaturday model is vetted out, maybe there could be enough justification to have SQLRally India. PASS needs to have a premier SQL event in that region. Going to USA or Europe for that matter is incredibly hard due to VISA issues etc. So this could be a case of where PASS comes closer to where the community is. Pinal: What portfolio would take on if you are elected to the PASS Board? Sri: There are some very strong folks on the PASS Board today. The President discusses the portfolios with the group and makes the final call on the portfolios. I am also a fan of having a team associated with the portfolios. In that case, one person is the primary for a portfolio but secondary on a couple of other portfolios. This way people on the board have a direct vested interest in a few portfolios. Personally, I know I would these portfolios good justice – Chapters, Global Growth and Events (SQLSat, SQLRally). I would try to see if we can get a director to focus on Volunteers.  To me that is very critical for growth in the international regions. Pinal: This is an interesting conversation with you Sri. I know you so long time but this is indeed inspiring to many. India is a big country and we appreciate your thoughts. Sri: Thank you very much for taking time to chat with me today. Cheers. There are pretty strong candidates for SQLPASS Board of Elections this year. I know all of them in person and honestly it is going to be extremely difficult to not to vote for anybody. I am indeed in a crunch right now how to pick one over another. Though the choice is difficult, I encourage you to vote for them. I am extremely confident that the new board of directors will all have the same goal – Better SQL Server Community. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Database, DBA, PostADay, SQL, SQL Authority, SQL PASS, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority News, T SQL, Technology

    Read the article

  • Discover What Powers Your Favorite Websites

    - by Matthew Guay
    Have you ever wondered if the site you’re visiting is powered by WordPress or if the webapp you’re using is powered by Ruby on Rails?  With these extensions for Google Chrome, you’ll never have to wonder again. Geeks love digging under the hood to see what makes their favorite apps and sites tick.  But opening the “View Source” window today doesn’t tell you everything there is to know about a website.  Plus, even if you can tell what CMS is powering a website from its source, it can be tedious to dig through lines of code to find what you’re looking for.  Also, the HTML code never tells you what web server a site is running on or what version of PHP it’s using.  With three extensions for Google Chrome you’ll never have to wonder again.  Note that some sites may not give as much information, but still, you’ll find enough data from most sites to be interesting. Discover Web Frameworks and Javascript Libraries with Chrome Sniffer If you want to know what CMS is powering a site or if it’s using Google Analytics or Quantcast, this is the extension for you.  Chrome Sniffer (link below) identifies over 40 different frameworks, and is constantly adding more.  It shows the logo of the main framework on the site on the left of your address bar.  Here wee see Chrome Sniffer noticed that How-To Geek is powered by WordPress.   Click the logo to see other frameworks on the site.  We can see that the site also has Google Analytics and Quantcast.  If you want more information about the framework, click on its logo and the framework’s homepage will open in a new tab. As another example, we can see that the Tumblr Staff blog is powered by Tumblr (of course), the Discus comment system, Quantcast, and the Prototype JavaScript framework. Or here’s a site that’s powered by Drupal, Google Analytics, Mollom spam protection, and jQuery.  Chrome Sniffer definitely uncovers a lot of neat stuff, so if you’re into web frameworks you’re sure to enjoy this extension. Find Out What Web Server The Site is Running On Want to know whether the site you’re looking at is running on IIS or Appache?  The Web Server Notifier extension for Chrome (link below) lets you easily recognize the web server a site is running on by its favicon on the right of the address bar.  Click the icon to see more information. Some web servers will show you a lot of information about their server, including version, operating system, PHP version, OpenSSL version, and more. Others will simply tell you their name. If the site is powered by IIS, you can usually tell the version of Windows Server its running on since the IIS versions are specific to a version of Windows.  Here we see that Microsoft.com is running on the latest and greatest – Windows Server 2008 R2 with IIS 7.5. Discover Web Technologies Powering Sites Wondering if a webapp is powered by Ruby on Rails or ASP.NET?  The Web Technology Notifier extension for Chrome (link below), from the same developer as the Web Server Notifier, will let you easily discover the backend of a site.  You’ll see the technology’s favicon on the right of your address bar, and, as with the other extension, can get more information by clicking the icon. Here we can see that Backpack from 37signals is powered by the Phusion Passenger module to run Ruby on Rails.   Microsoft’s new Docs.com Office Online apps is powered by ASP.NET…   And How-To Geek has PHP running to power WordPress. Conclusion With all these tools at hand, you can find out a lot about your favorite sites.  For example, with all three extensions we can see that How-To Geek runs on WordPress with PHP, uses Google Analytics and Quantcast, and is served by the LightSpeed web server.  Fun info, huh?   Links Download the Chrome Sniffer extension Download the Web Server Notifier extension Download the Web Technology Notifier extension Similar Articles Productive Geek Tips Enjoy a Clean Start Page with New Tab PageEnjoy Image Zooming on Your Favorite Photo Websites in ChromeAdd Your Own Folders to Favorites in Windows 7Find User Scripts for Your Favorite Websites the Easy WayAdd Social Elements to Your Gmail Contacts with Rapportive TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Xobni Plus for Outlook All My Movies 5.9 CloudBerry Online Backup 1.5 for Windows Home Server Snagit 10 tinysong gives a shortened URL for you to post on Twitter (or anywhere) 10 Superb Firefox Wallpapers OpenDNS Guide Google TV The iPod Revolution Ultimate Boot CD can help when disaster strikes

    Read the article

  • SQL Table stored as a Heap - the dangers within

    - by MikeD
    Nearly all of the time I create a table, I include a primary key, and often that PK is implemented as a clustered index. Those two don't always have to go together, but in my world they almost always do. On a recent project, I was working on a data warehouse and a set of SSIS packages to import data from an OLTP database into my data warehouse. The data I was importing from the business database into the warehouse was mostly new rows, sometimes updates to existing rows, and sometimes deletes. I decided to use the MERGE statement to implement the insert, update or delete in the data warehouse, I found it quite performant to have a stored procedure that extracted all the new, updated, and deleted rows from the source database and dump it into a working table in my data warehouse, then run a stored proc in the warehouse that was the MERGE statement that took the rows from the working table and updated the real fact table. Use Warehouse CREATE TABLE Integration.MergePolicy (PolicyId int, PolicyTypeKey int, Premium money, Deductible money, EffectiveDate date, Operation varchar(5)) CREATE TABLE fact.Policy (PolicyKey int identity primary key, PolicyId int, PolicyTypeKey int, Premium money, Deductible money, EffectiveDate date) CREATE PROC Integration.MergePolicy as begin begin tran Merge fact.Policy as tgtUsing Integration.MergePolicy as SrcOn (tgt.PolicyId = Src.PolicyId) When not matched by Target then Insert (PolicyId, PolicyTypeKey, Premium, Deductible, EffectiveDate)values (src.PolicyId, src.PolicyTypeKey, src.Premium, src.Deductible, src.EffectiveDate) When matched and src.Operation = 'U' then Update set PolicyTypeKey = src.PolicyTypeKey,Premium = src.Premium,Deductible = src.Deductible,EffectiveDate = src.EffectiveDate When matched and src.Operation = 'D' then Delete ;delete from Integration.WorkPolicy commit end Notice that my worktable (Integration.MergePolicy) doesn't have any primary key or clustered index. I didn't think this would be a problem, since it was relatively small table and was empty after each time I ran the stored proc. For one of the work tables, during the initial loads of the warehouse, it was getting about 1.5 million rows inserted, processed, then deleted. Also, because of a bug in the extraction process, the same 1.5 million rows (plus a few hundred more each time) was getting inserted, processed, and deleted. This was being sone on a fairly hefty server that was otherwise unused, and no one was paying any attention to the time it was taking. This week I received a backup of this database and loaded it on my laptop to troubleshoot the problem, and of course it took a good ten minutes or more to run the process. However, what seemed strange to me was that after I fixed the problem and happened to run the merge sproc when the work table was completely empty, it still took almost ten minutes to complete. I immediately looked back at the MERGE statement to see if I had some sort of outer join that meant it would be scanning the target table (which had about 2 million rows in it), then turned on the execution plan output to see what was happening under the hood. Running the stored procedure again took a long time, and the plan output didn't show me much - 55% on the MERGE statement, and 45% on the DELETE statement, and table scans on the work table in both places. I was surprised at the relative cost of the DELETE statement, because there were really 0 rows to delete, but I was expecting to see the table scans. (I was beginning now to suspect that my problem was because the work table was being stored as a heap.) Then I turned on STATS_IO and ran the sproc again. The output was quite interesting.Table 'Worktable'. Scan count 0, logical reads 0, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.Table 'Policy'. Scan count 0, logical reads 0, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.Table 'MergePolicy'. Scan count 1, logical reads 433276, physical reads 60, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0. I've reproduced the above from memory, the details aren't exact, but the essential bit was the very high number of logical reads on the table stored as a heap. Even just doing a SELECT Count(*) from Integration.MergePolicy incurred that sort of output, even though the result was always 0. I suppose I should research more on the allocation and deallocation of pages to tables stored as a heap, but I haven't, and my original assumption that a table stored as a heap with no rows would only need to read one page to answer any query was definitely proven wrong. It's likely that some sort of physical defragmentation of the table may have cleaned that up, but it seemed that the easiest answer was to put a clustered index on the table. After doing so, the execution plan showed a cluster index scan, and the IO stats showed only a single page read. (I aborted my first attempt at adding a clustered index on the table because it was taking too long - instead I ran TRUNCATE TABLE Integration.MergePolicy first and added the clustered index, both of which took very little time). I suspect I may not have noticed this if I had used TRUNCATE TABLE Integration.MergePolicy instead of DELETE FROM Integration.MergePolicy, since I'm guessing that the truncate operation does some rather quick releasing of pages allocated to the heap table. In the future, I will likely be much more careful to have a clustered index on every table I use, even the working tables. Mike  

    Read the article

  • Polite busy-waiting with WRPAUSE on SPARC

    - by Dave
    Unbounded busy-waiting is an poor idea for user-space code, so we typically use spin-then-block strategies when, say, waiting for a lock to be released or some other event. If we're going to spin, even briefly, then we'd prefer to do so in a manner that minimizes performance degradation for other sibling logical processors ("strands") that share compute resources. We want to spin politely and refrain from impeding the progress and performance of other threads — ostensibly doing useful work and making progress — that run on the same core. On a SPARC T4, for instance, 8 strands will share a core, and that core has its own L1 cache and 2 pipelines. On x86 we have the PAUSE instruction, which, naively, can be thought of as a hardware "yield" operator which temporarily surrenders compute resources to threads on sibling strands. Of course this helps avoid intra-core performance interference. On the SPARC T2 our preferred busy-waiting idiom was "RD %CCR,%G0" which is a high-latency no-nop. The T4 provides a dedicated and extremely useful WRPAUSE instruction. The processor architecture manuals are the authoritative source, but briefly, WRPAUSE writes a cycle count into the the PAUSE register, which is ASR27. Barring interrupts, the processor then delays for the requested period. There's no need for the operating system to save the PAUSE register over context switches as it always resets to 0 on traps. Digressing briefly, if you use unbounded spinning then ultimately the kernel will preempt and deschedule your thread if there are other ready threads than are starving. But by using a spin-then-block strategy we can allow other ready threads to run without resorting to involuntary time-slicing, which operates on a long-ish time scale. Generally, that makes your application more responsive. In addition, by blocking voluntarily we give the operating system far more latitude regarding power management. Finally, I should note that while we have OS-level facilities like sched_yield() at our disposal, yielding almost never does what you'd want or naively expect. Returning to WRPAUSE, it's natural to ask how well it works. To help answer that question I wrote a very simple C/pthreads benchmark that launches 8 concurrent threads and binds those threads to processors 0..7. The processors are numbered geographically on the T4, so those threads will all be running on just one core. Unlike the SPARC T2, where logical CPUs 0,1,2 and 3 were assigned to the first pipeline, and CPUs 4,5,6 and 7 were assigned to the 2nd, there's no fixed mapping between CPUs and pipelines in the T4. And in some circumstances when the other 7 logical processors are idling quietly, it's possible for the remaining logical processor to leverage both pipelines. Some number T of the threads will iterate in a tight loop advancing a simple Marsaglia xor-shift pseudo-random number generator. T is a command-line argument. The main thread loops, reporting the aggregate number of PRNG steps performed collectively by those T threads in the last 10 second measurement interval. The other threads (there are 8-T of these) run in a loop busy-waiting concurrently with the T threads. We vary T between 1 and 8 threads, and report on various busy-waiting idioms. The values in the table are the aggregate number of PRNG steps completed by the set of T threads. The unit is millions of iterations per 10 seconds. For the "PRNG step" busy-waiting mode, the busy-waiting threads execute exactly the same code as the T worker threads. We can easily compute the average rate of progress for individual worker threads by dividing the aggregate score by the number of worker threads T. I should note that the PRNG steps are extremely cycle-heavy and access almost no memory, so arguably this microbenchmark is not as representative of "normal" code as it could be. And for the purposes of comparison I included a row in the table that reflects a waiting policy where the waiting threads call poll(NULL,0,1000) and block in the kernel. Obviously this isn't busy-waiting, but the data is interesting for reference. _table { border:2px black dotted; margin: auto; width: auto; } _tr { border: 2px red dashed; } _td { border: 1px green solid; } _table { border:2px black dotted; margin: auto; width: auto; } _tr { border: 2px red dashed; } td { background-color : #E0E0E0 ; text-align : right ; } th { text-align : left ; } td { background-color : #E0E0E0 ; text-align : right ; } th { text-align : left ; } Aggregate progress T = #worker threads Wait Mechanism for 8-T threadsT=1T=2T=3T=4T=5T=6T=7T=8 Park thread in poll() 32653347334833483348334833483348 no-op 415 831 124316482060249729303349 RD %ccr,%g0 "pause" 14262429269228623013316232553349 PRNG step 412 829 124616702092251029303348 WRPause(8000) 32443361333133483349334833483348 WRPause(4000) 32153308331533223347334833473348 WRPause(1000) 30853199322432513310334833483348 WRPause(500) 29173070315032223270330933483348 WRPause(250) 26942864294930773205338833483348 WRPause(100) 21552469262227902911321433303348

    Read the article

  • Short Season, Long Models - Dealing with Seasonality

    - by Michel Adar
    Accounting for seasonality presents a challenge for the accurate prediction of events. Examples of seasonality include: ·         Boxed cosmetics sets are more popular during Christmas. They sell at other times of the year, but they rise higher than other products during the holiday season. ·         Interest in a promotion rises around the time advertising on TV airs ·         Interest in the Sports section of a newspaper rises when there is a big football match There are several ways of dealing with seasonality in predictions. Time Windows If the length of the model time windows is short enough relative to the seasonality effect, then the models will see only seasonal data, and therefore will be accurate in their predictions. For example, a model with a weekly time window may be quick enough to adapt during the holiday season. In order for time windows to be useful in dealing with seasonality it is necessary that: The time window is significantly shorter than the season changes There is enough volume of data in the short time windows to produce an accurate model An additional issue to consider is that sometimes the season may have an abrupt end, for example the day after Christmas. Input Data If available, it is possible to include the seasonality effect in the input data for the model. For example the customer record may include a list of all the promotions advertised in the area of residence. A model with these inputs will have to learn the effect of the input. It is possible to learn it specific to the promotion – and by the way learn about inter-promotion cross feeding – by leaving the list of ads as it is; or it is possible to learn the general effect by having a flag that indicates if the promotion is being advertised. For inputs to properly represent the effect in the model it is necessary that: The model sees enough events with the input present. For example, by virtue of the model lifetime (or time window) being long enough to see several “seasons” or by having enough volume for the model to learn seasonality quickly. Proportional Frequency If we create a model that ignores seasonality it is possible to use that model to predict how the specific person likelihood differs from average. If we have a divergence from average then we can transfer that divergence proportionally to the observed frequency at the time of the prediction. Definitions: Ft = trailing average frequency of the event at time “t”. The average is done over a suitable period of to achieve a statistical significant estimate. F = average frequency as seen by the model. L = likelihood predicted by the model for a specific person Lt = predicted likelihood proportionally scaled for time “t”. If the model is good at predicting deviation from average, and this holds over the interesting range of seasons, then we can estimate Lt as: Lt = L * (Ft / F) Considering that: L = (L – F) + F Substituting we get: Lt = [(L – F) + F] * (Ft / F) Which simplifies to: (i)                  Lt = (L – F) * (Ft / F)  +  Ft This latest expression can be understood as “The adjusted likelihood at time t is the average likelihood at time t plus the effect from the model, which is calculated as the difference from average time the proportion of frequencies”. The formula above assumes a linear translation of the proportion. It is possible to generalize the formula using a factor which we will call “a” as follows: (ii)                Lt = (L – F) * (Ft / F) * a  +  Ft It is also possible to use a formula that does not scale the difference, like: (iii)               Lt = (L – F) * a  +  Ft While these formulas seem reasonable, they should be taken as hypothesis to be proven with empirical data. A theoretical analysis provides the following insights: The Cumulative Gains Chart (lift) should stay the same, as at any given time the order of the likelihood for different customers is preserved If F is equal to Ft then the formula reverts to “L” If (Ft = 0) then Lt in (i) and (ii) is 0 It is possible for Lt to be above 1. If it is desired to avoid going over 1, for relatively high base frequencies it is possible to use a relative interpretation of the multiplicative factor. For example, if we say that Y is twice as likely as X, then we can interpret this sentence as: If X is 3%, then Y is 6% If X is 11%, then Y is 22% If X is 70%, then Y is 85% - in this case we interpret “twice as likely” as “half as likely to not happen” Applying this reasoning to (i) for example we would get: If (L < F) or (Ft < (1 / ((L/F) + 1)) Then  Lt = L * (Ft / F) Else Lt = 1 – (F / L) + (Ft * F / L)  

    Read the article

< Previous Page | 157 158 159 160 161 162 163 164 165 166 167 168  | Next Page >