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  • If you had three months to learn one relatively new technology, which one would you choose?

    - by Ivo van der Wijk
    This question was taken from CodingHorror. On my list would be (and some actually are): Android Development (and possibly iPhone development) Go language and its concurrency NoSQL, specifically CouchDB RCTK, which happens to be my own idea / project (but all ideas have been thought or already, what matters is my implementation) But I don't think I'm being cutting-edge/thinking-outside-the-box here. What's on your list? Please don't restrict yourself to the list above - that's my list. I'm interested in hearing what others find interesting new technology.

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  • Microsoft and Joyent Announce Node.js Windows Port

    With the Node.js command line tool, developers can type ?node my_app.js.' to run JavaScript programs. It gives developers a JavaScript application programming interface (API) supplies access for the network and file system as well. One instance where Node.js often comes in handy is in the creation of scalable networked programs that emphasize high concurrency and low response times. Developers who wish to use Node.js use on Windows at this time must do so running a virtual machine with Linux. Claudia Caldato, Principal Program Manager of Microsoft's Interoperability Strategy Team, offered...

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  • Using an actor model versus a producer-consumer model?

    - by hewhocutsdown
    I'm doing some early-stage research towards architecting a new software application. Concurrency and multithreading will likely play a significant part, so I've been reading up on the various topics. The producer-consumer model, at least how it is expressed in Java, has some surface similarities but appears to be deeply dissimilar to the actor model in use with languages such as Erlang and Scala. I'm having trouble finding any good comparative data, or specific reasons to use or avoid the one or the other. Is the actor model even possible with Java or C#, or do you have do use one of the languages built for the purpose? Is there a third way?

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  • Preparing for interview questions involving scale

    - by Chaitanya
    I have over 6 years of software development experience. I have worked on multiple platforms, including mobile. However, I have not had a chance of working on scale-related issues. As a consequence, whenever someone asks a question involving a million inputs in an interview, I find myself out of depth. How do I prepare for such questions? Any books/resources to refer to? There are books for Java and Data Structures and Concurrency, but I don't know about any definitive ones to learn about scaling.

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  • What are the recommended resources for learning about the Actor model of concurrent systems?

    - by Larry OBrien
    The Actor concurrency model is clearly gaining favor. Is there a good book that presents the patterns and pitfalls of the model? I am thinking about something that would discuss, for instance, the problems of consistency and correctness in the context of hundreds or thousands of independent Actors. It would be okay if it were associated with a specific language (Erlang, I would imagine, since that seems universally regarded as the proven implementation of Actors), but I am hoping for something more than an introductory chapter or two. I'm actually most interested in Actors as they are implemented in Scala, if there are any such resources available.

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  • web services, J2EE, spring, DB integration project ideas- maybe data mining related?

    - by sj88
    Hey guys, I am a graduate CS student (Data mining and machine learning) and have a good exposure to core JAVA (3 years). I have read up a bunch of stuff on Design patterns J2EE Web services( soap and rest) spring and hibernate Java Concurrency - advanced features like Task and Executors. I would now like to do a project combining this stuff (over my free time of corse) to get a better understanding of these things and to kind of make an end to end software (to learn the best design principles etc + svn, maven). Any good project ideas would be really appreciated. I just wanna build this stuff to learn so I dont really mind re-inventing the wheel. Also, anything related to data mining would be an added bonus (fits with my research) but absolutly not necesary (since this project is more to learn to do large scale software developement)

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  • JavaFX 2.1.1 Documentation

    - by NancyH
    JavaFX 2.1.1 released on June 12, and few documents were updated on the docs.oracle.com/javafx website. Besides a new set of release documentation, the Concurrency in JavaFX article was updated with a discussion of how to cancel a task, with a code sample to illustrate that. A new section describes the WorkerStateEvent class and how to use the convenience methods such as cancelled, failed, running, scheduled, and succeeded, which are invoked when the Worker implementation state changes. Other documents were updated to reflect minor bug fixes, many of them contributed by JavaFX readers using the feedback alias in the sidebar of all of our documentation. Yes, we do respond and pay attention to what you say and at least try to point you in the right direction if we can't solve a problem you're having with a tutorial. We appreciate your feedback!

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  • Is C++ indispensible for AAA game engines, as long as we have console-platform games? [closed]

    - by user1174924
    C++ has remained the industry standard for game engines much because of its features.. The primary reasons are(afaik): Technical reasons - High performance, native runtime, portibility, negligible latency, and more recently concurrency. Socio-Technical reasons - Availability of Libraries, Legecy stuff, most scripting languages on games have a good C api (ex lua), Good IDEs and most recently improved Development time.(C++11) Social reasons - People know C++, Licenced technologies, and battle proven. Does this make C++ for game engines indispensible, so long we have game consoles? Would not, the above features make me implement new graphics technology in C++ only? Edit: Will learning C++ garuntee me a job as a game engine dev In the future? I want to master every aspect of the language, but I already know C# and python. Should I allocate my time learning C++. I want to be a game engine developer.

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  • Is there any complications or side effects for changing final field access/visibility modifier from private to protected?

    - by Software Engeneering Learner
    I have a private final field in one class and then I want to address that field in a subclass. I want to change field access/visibility modifier from private to protected, so I don't have to call getField() method from subclass and I can instead address that field directly (which is more clear and cohessive). Will there be any side effects or complications if I change private to protected for a final field? UPDATE: from logical point of view, it's obvious that descendant should be able to directly access all predecessor fields, right? But there are certain constraints that are imposed on private final fields by JVM, like 100% initialization guarantee after construction phase(useful for concurrency) and so on. So I would like to know, by changing from private to protected, won't that or any other constraints be compromised?

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  • Using XA Transactions in Coherence-based Applications

    - by jpurdy
    While the costs of XA transactions are well known (e.g. increased data contention, higher latency, significant disk I/O for logging, availability challenges, etc.), in many cases they are the most attractive option for coordinating logical transactions across multiple resources. There are a few common approaches when integrating Coherence into applications via the use of an application server's transaction manager: Use of Coherence as a read-only cache, applying transactions to the underlying database (or any system of record) instead of the cache. Use of TransactionMap interface via the included resource adapter. Use of the new ACID transaction framework, introduced in Coherence 3.6.   Each of these may have significant drawbacks for certain workloads. Using Coherence as a read-only cache is the simplest option. In this approach, the application is responsible for managing both the database and the cache (either within the business logic or via application server hooks). This approach also tends to provide limited benefit for many workloads, particularly those workloads that either have queries (given the complexity of maintaining a fully cached data set in Coherence) or are not read-heavy (where the cost of managing the cache may outweigh the benefits of reading from it). All updates are made synchronously to the database, leaving it as both a source of latency as well as a potential bottleneck. This approach also prevents addressing "hot data" problems (when certain objects are updated by many concurrent transactions) since most database servers offer no facilities for explicitly controlling concurrent updates. Finally, this option tends to be a better fit for key-based access (rather than filter-based access such as queries) since this makes it easier to aggressively invalidate cache entries without worrying about when they will be reloaded. The advantage of this approach is that it allows strong data consistency as long as optimistic concurrency control is used to ensure that database updates are applied correctly regardless of whether the cache contains stale (or even dirty) data. Another benefit of this approach is that it avoids the limitations of Coherence's write-through caching implementation. TransactionMap is generally used when Coherence acts as system of record. TransactionMap is not generally compatible with write-through caching, so it will usually be either used to manage a standalone cache or when the cache is backed by a database via write-behind caching. TransactionMap has some restrictions that may limit its utility, the most significant being: The lock-based concurrency model is relatively inefficient and may introduce significant latency and contention. As an example, in a typical configuration, a transaction that updates 20 cache entries will require roughly 40ms just for lock management (assuming all locks are granted immediately, and excluding validation and writing which will require a similar amount of time). This may be partially mitigated by denormalizing (e.g. combining a parent object and its set of child objects into a single cache entry), at the cost of increasing false contention (e.g. transactions will conflict even when updating different child objects). If the client (application server JVM) fails during the commit phase, locks will be released immediately, and the transaction may be partially committed. In practice, this is usually not as bad as it may sound since the commit phase is usually very short (all locks having been previously acquired). Note that this vulnerability does not exist when a single NamedCache is used and all updates are confined to a single partition (generally implying the use of partition affinity). The unconventional TransactionMap API is cumbersome but manageable. Only a few methods are transactional, primarily get(), put() and remove(). The ACID transactions framework (accessed via the Connection class) provides atomicity guarantees by implementing the NamedCache interface, maintaining its own cache data and transaction logs inside a set of private partitioned caches. This feature may be used as either a local transactional resource or as logging XA resource. However, a lack of database integration precludes the use of this functionality for most applications. A side effect of this is that this feature has not seen significant adoption, meaning that any use of this is subject to the usual headaches associated with being an early adopter (greater chance of bugs and greater risk of hitting an unoptimized code path). As a result, for the moment, we generally recommend against using this feature. In summary, it is possible to use Coherence in XA-oriented applications, and several customers are doing this successfully, but it is not a core usage model for the product, so care should be taken before committing to this path. For most applications, the most robust solution is normally to use Coherence as a read-only cache of the underlying data resources, even if this prevents taking advantage of certain product features.

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  • Pooling (Singleton) Objects Against Connection Pools

    - by kolossus
    Given the following scenario A canned enterprise application that maintains its own connection pool A homegrown client application to the enterprise app. This app is built using Spring framework, with the DAO pattern While I may have a simplistic view of this, I think the following line of thinking is sound: Having a fixed pool of DAO objects, holding on to connection objects from the pool. Clearly, the pool should be capable of scaling up (or down depending on need) and the connection objects must outnumber the DAOs by a healthy margin. Good Instantiating brand new DAOs for every request to access the enterprise app; each DAO will attempt to grab a connection from the pool and release it when it's done. Bad Since these are service objects, there will be no (mutable) state held by the objects (reduced risk of concurrency issues) I also think that with #1, there should be little to no resource contention, while in #2, there'll almost always be a DAO waiting to be serviced. Is my thinking correct and what could go wrong?

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  • The architecture and technologies to use for a secure, fast, reliable and easily scalable web application

    - by DSoul
    ^ For actual questions, skip to the lists down below I understand, that his is a vague topic, but please, before you turn the other way and disregard me, hear me out. I am currently doing research for a web application(I don't know if application is the correct word for it, but I will proceed w/ that for now), that one day might need to be everything mentioned in the title. I am bound by nothing. That means that every language, OS and framework is acceptable, but only if it proves it's usefulness. And if you are going to say, that scalability and speed depend on the code I write for this application, then I agree, but I am just trying to find something, that wouldn't stand in my way later on. I have done quite a bit reading on this subject, but I still don't have a clear picture, to what suits my needs, so I come to you, StackOverflow, to give me directions. I know you all must be wondering what I'm building, but I assure you, that it doesn't matter. I have heard of 12 factor app though, if you have any similar guidelines or what is, to suggest the please, go ahead. For the sake of keeping your answers as open as possible, I'm not gonna provide you my experience regarding anything written in this question. ^ Skippers, start here First off - the weights of the requirements are probably something like that (on a scale of 10): Security - 10 Speed - 5 Reliability (concurrency) - 7.5 Scalability - 10 Speed and concurrency are not a top priority, in the sense, that the program can be CPU intensive, and therefore slow, and only accept a not-that-high number of concurrent users, but both of these factors must be improvable by scaling the system Anyway, here are my questions: How many layers should the application have, so it would be future-proof and could best fulfill the aforementioned requirements? For now, what I have in mind is the most common version: Completely separated front end, that might be a web page or an MMI application or even both. Some middle-ware handling communication between the front and the back end. This is probably a server that communicates w/ the front end via HTTP. How the communication w/ the back end should be handled is probably dependent on the back end. The back end. Something that handles data through resources like DB and etc. and does various computations w/ the data. This, as the highest priority part of the software, must be easily spread to multiple computers later on and have no known security holes. I think ideally the middle-ware should send a request to a queue from where one of the back end processes takes this request, chops it up to smaller parts and buts these parts of the request back onto the same queue as the initial request, after what these parts will be then handled by other back end processes. Something *map-reduce*y, so to say. What frameworks, languages and etc. should these layers use? The technologies used here are not that important at this moment, you can ignore this part for now I've been pointed to node.js for this part. Do you guys know any better alternatives, or have any reasons why I should (not) use node.js for this particular job. I actually have no good idea, what to use for this job, there are too many options out there, so please direct me. This part (and the 2. one also, I think) depend a lot on the OS, so suggest any OSs alongside w/ the technologies/frameworks. Initially, all computers (or 1 for starters) hosting the back end are going to be virtual machines. Please do give suggestions to any part of the question, that you feel you have comprehensive knowledge and/or experience of. And also, point out if you feel that any part of the current set-up means an instant (or even distant) failure or if I missed a very important aspect to consider. I'm not looking for a definitive answer for how to achieve my goals, because there certainly isn't one, for I haven't provided you w/ all the required information. I'm just looking for recommendations and directions on what to look into. Also, bare in mind, that this isn't something that I have to get done quickly, to sell and let it be re-written by the new owner (which, I've been told for multiple times, is what I should aim for). I have all the time in the world and I really just want to learn doing something really high-end. Also, excuse me if my language isn't the best, I'm not a native. Anyway. Thanks in advance to anyone, who takes the time to help me out here. PS. When I do seem to come up w/ a good architecture/design for this project, I will certainly make it an open project and keep you guys up to date w/ it's development. As in what you could have told me earlier and etc. For obvious reasons the very same question got closed on SO, but could you guys still help me?.

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  • Adopt a Java EE 7 JSR!

    - by reza_rahman
    Broad community participation is key to the success of any technology worth it's salt. The Adopt-a-JSR program was launched in recognition of this fact. It is an initiative by some key JUG leaders around the World to encourage JUG members to get involved in a JSR and to evangelize that JSR to their JUG and the wider Java community, in order to increase grass roots participation. There are a number of JUGs that have already jumped in like the Chennai JUG, SouJava, London Java Community, BeJUG, GoJava, Morrocco JUG, Campinas JUG and ItpJava. Note that any developer can participate, there isn't a need to be a JUG leader. There are a number of Java EE 7 JSRs that could use your help right now including WebSocket, JSON, Caching, Concurrency for EE, JAX-RS2 and JMS2. Find out more here.

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  • Database Context and Singleton injection with IoC

    - by zaitsman
    All of the below relates to a ASP.NET c# app. I have a Singleton Settings MemoryCache that reads values from database on first access and caches these, then invalidates them using SQL Service Broker message and re-reads as required. For the purposes of standard controllers, i create my Db Context in a request scope. However, this obviously means that i can't use the same context in the Settings Cache class, since that is a singleton and we have a scope collision. At the moment, i ended up with two db contexts - the Controllers get it via IoC container, whereas a Singleton just creates it's own. However, i am not satisfied with this approach (mostly due to the way i feel about two contexts, the cache doesn't set anything on the db hence concurrency is not an issue as much). What is a better way to do it?

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  • how to enrich my programming background? [on hold]

    - by city
    I am not sure whether I post my question in right place. I am a master student in computer science and I will graduate next year.Recently, I failed in an interview. Because (at least I think) the interviewer did not think my background strong enough although I finished 5 courses projects and currently working on other 2 projects in graduate school. It seems that nowadays, recruiters like these candidates who finish some projects out of school/work. So I wanna enrich my background. So, I hope you guys recommend some java/C++ projects to me, which I can finish in two or three months. And it would be better if concurrency programming or other fancy skills are needed.

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  • How can I keep a file in Windows 7's cache?

    - by netvope
    Sometimes you know better than Windows what files will be re-used later. Suppose you have 8GB of memory, and you use the same 1GB file every hour in an I/O-bound application (which takes 1 second to finish if the file is cached, and 1 minute if not.) Now you process some other 16GB of data that are not going to be re-used. Naturally the frequently used 1GB file will be pushed out of the cache. It would be beneficial if one can tell Windows to keep that 1GB file in memory. (Better yet, it would be great if I can tell Windows not to cache those 16GB of data, but I'm not optimistic that this can be done.) The poor-man's way to keep a file in the cache would be to keep reading the file. Are there any better ways? Are you aware of any programs that do this? (If this can be easily done under Linux, please let me know too.)

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  • Using Superuser paths for specific topics

    - by Stenemo
    I have a very specific question, which I have not been able to find the solution I want to search Superuser and other websites using Google, but I want to limit it to a specific subject (e.g. the R programming language). Using Superuser paths for specific topics like "site:http://superuser.com/questions/tagged/r" Does not work, as can be seen when comparing searching using full path compared to searching entire website with more specific question. Also note the first hit being one step in the direction i want, but since this path itself does not hold the questions in its path it does not solve my issue. There should however be a better way to do this, e.g. by having a very specific Google search tag for the R programming language, which would have to be either in the path, on the webpage, or tagged differently. Seeing as Superuser has a good tag system I am optimistic that this can be used to solve my question. Is there a solution to this that always works on Superuser and similar sites?

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  • Upgrade a legacy, expired RHEL 3.4.6 server to modern Centos/Scientific Linux

    - by Gabriel Tasiopoulos
    I have a machine running a legacy J2EE app. The code is not Maven-ized and it works with pretty old Java and Postgres versions. I have converted it to a VM in ESXI and I'd like to try to upgrade it to a modern, binary-compatible version of RHEL (Centos or Scientific LInux) and see if things would still work. Where should I start? Am I being too optimistic with this one? It's more of an experiment and I'm not doing it on a production machine. But given the OS is pretty old I am looking for a way to do this eventually. Many thanks

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  • Google Analytics and Whos.amung.us in realtime visitors, why such an enormous discrepancy?

    - by jacouh
    Since years I use in a site both Google Analytics and Whos.amung.us, both Google analytics and whos.amung.us javascripts are inserted in the same pages in the tracked part of the site. In real-time visitors, why such an enormous discrepancy ? for example at the moment, Google analytics gives me 9 visitors, whos.amung.us indicates 59, a ratio of 6 times? Why whos.amung.us is 6 times optimistic than Google Analytics in terms of the realtime visitors? Google whos.amung.us My question is: whos.amung.us does not detect robots while Google does? GA ignores visitors from some countries, not whos.amung.us? Some robots/bots execute whos.amung.us javascript for tracking? While no robots/bots can execute the tracking javascript provided by Google Analytics? To facilitate your analysis, I copy JS code used below: Google analytics: <script type="text/javascript"> var _gaq = _gaq || []; _gaq.push(['_setAccount', 'MyGaAccountNo']); _gaq.push(['_trackPageview']); (function() { var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); })(); </script> Whos.amung.us: <script>var _wau = _wau || []; _wau.push(["tab", "MyWAUAccountNo", "c6x", "right-upper"]);(function() { var s=document.createElement("script"); s.async=true; s.src="http://widgets.amung.us/tab.js";document.getElementsByTagName("head")[0].appendChild(s);})();</script> I've aleady signaled this to WAU staff some time ago, NR, I've not done this to Google as they don't handle this kind of feedback. Thank you for your explanations.

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  • Thoughts on the new JavaFX by Jim Connors

    - by Jacob Lehrbaum
    First, a brief editorial if I may.  The upcoming JavaFX 2.0 platform has been getting overwhelmingly positive reaction from the community so far.  While the public sentiment seems to be cautiously optimistic, I've heard nothing but positive reactions from everyone that I've spoken to about the platform.   In fact, many of the early adopters of JavaFX have told us directly that they are very encouraged about the direction the platform is taking.One such early adopter is Oracle's own Jim Connors.  As his day job, Jim is a principal sales consultant (basically an engineer that supports Oracle's sales efforts) in the New York area.  However, Jim also co-wrote a book with Jim Clarke and Eric Bruno on JavaFX and has spoken and conducted training sessions at events like the New York Java Developer Day, the Java Road Trip, and other events.In his thoughtful editorial, Jim discusses some of the reasons why he believes the new directions Oracle is taking JavaFX make sense, including:Better developer toolsLower barriers to adoption -> better accessibility to existing Java developersImproved performanceMore flexibility (ability to use other dynamic languages, etc)To read more about Jim's thoughts on the new JavaFX, check out his blog.  Or if you want to learn more about the JavaFX platform, pick up a copy of his book.  And if you still want to use JavaFX Script, you can check out Project Visage

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  • PASS 13 Dispatches: Memory Optimized = On

    - by Tony Davis
    I'm at the PASS Summit in Charlotte for the Day 1 keynote by Quentin Clarke, Corporate VP of the data platform group at Microsoft. He's talking about how SQL Server 2014 is “pushing boundaries” and first up is SQL Server 2014's In-Memory OLTP technology (former codename “hekaton”) It is a feature that provokes a lot of interest and for good reason as, without any need for application rewrites or hardware updates, it can enable us to ensure that an application can find in memory most or all of the data it needs, and can lead to huge improvements in processing times. A good recent hekaton use cases article talks about applications that need a “Shock Absorber” when either spikes or just a high rate of incoming workload (including data in ETL scenarios) become a primary bottleneck. To get a really deep look at this technology, I would check out David DeWitt's summit keynote tomorrow (it will be live streamed). Other than that, to get started I'd recommend Kalen Delaney's whitepaper. She offers a lot of insight into how it works and how to start to define memory-optimized tables, and natively compiled stored procedures. These memory-optimized tables uses completely optimistic multi-version concurrency control – no waiting on locks! After that, Tom LaRock has compiled a useful set of links to drill deeper, and includes one to Microsoft's AMR tool to help you gauge the tables that might benefit most. Tony.

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  • Show Notes: Getting Past the Cloud Hype

    - by Bob Rhubart
    This week’s ArchBeat podcast features an unvarnished bit of conversation culled from a recent virtual meet-up. These meet-ups are informal conversations among architects, many of who have participated in previous ArchBeat programs. There’s no prearranged topic, so the participants talk about whatever is on their minds. The most recent meet-up included Oracle ACE Director Ran Batra, director of cloud computing product development with AT&T, and Daniel Templeton, principal product manager for Oracle Grid Engine, and the man behind Dan T’s GridBlog. The conversation took place at the end of the year – and the end of the decade – a time when most tech publications feature their predictions for the coming year.  I wanted a different spin on that theme, so I asked Ron and Dan to talk about the technologies about which they weren’t all that optimistic.   I found that ten-minute chunk of conversation particularly interesting, so that’s what you’re going to hear this week. Listen Get Social If you have questions or comment for Ron and/or Daniel you can connect via the following: Ron Batra Blog | Twitter | LinkedIn | Oracle Mix | Oracle ACE Profile Daniel Templeton Blog | Twitter | LinkedIn Coming Up Oracle ACE Director Debra Lilley talks about her role in the UKOUG’s development group and that group’s collaboration with Oracle on Oracle Fusion Applications. Dr Frank Munz, author of Middleware and Cloud Computing: Oracle Fusion Middleware on Amazon Web Services and Rackspace Cloud. Stay tuned: http://feeds2.feedburner.com/OtnArch2ArchRSS   del.icio.us Tags: oracle,oracle technology network,archbeat,cloud computing,software architect,podcast Technorati Tags: oracle,oracle technology network,archbeat,cloud computing,software architect,podcast

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  • How to get Autocad working with Wine?

    - by gabriel
    I am trying 3 years now installing Autocad,*3ds Max* and Revit architecture on Ubuntu with wine! Every year I am very optimistic 'cause I see the new wine versions already improved. So, now I am starting again in a clean Ubuntu installation to install Autocad 2013 with wine 1.4. I am not trying to have an answer only for me, but I want this community to try and finally we can achieve that! The winetricks have already net framework 4 to install which is the reason I have not already ran to the past Autocad. So, I would like to remove completely my windows 7 partition from my pc and go on a linux machine without loosing the powerfull architectural programms.I know all about Blender and staff so I just want you to help find a solution on that, because I know there is a solution! Maybe I will have to learn all the c++ or python etc. But I am sure that a solution can come with the help of all of us! Any suggestion about this problem will be very nice and helpfull.

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  • What the Hekaton?

    - by Tony Davis
    Hekaton, the power behind SQL Server 2014′s In-Memory OLTP technology, is intended to make data operations run orders of magnitude faster on SQL Server. This works its magic partly by serving database workloads entirely from main memory, using memory-optimized table structures. It replaces the relational engine’s standard locking model with an optimistic concurrency model based on time-stamped row versions. Deeper down the Hekaton engine uses new, ‘latch free’ data structures. So far, so good, but performance improvements on this scale require a compromise, and the compromise is that these aren’t tables as we understand them. For the database developer, these differences are painful because they involve sacrificing some very important bits of the relational model. Most importantly, Hekaton tables don’t currently support FOREIGN KEY constraints or CHECK constraints, and you can’t put the checks in triggers because there aren’t any DML triggers either. Constraints allow a relational designer to enforce relational integrity and data integrity. Without them, of course, ‘bad data’ can get into our Hekaton tables. There is no easy way of preventing it. For several classes of database and data, this is a show-stopper. One may regard all these restrictions regretfully, seeing limited opportunity to try out Hekaton with current databases, but perhaps there is also a sudden glow of recognition. Isn’t this how we all originally imagined table variables were going to be, back in SQL 2005? And they have much the same restrictions. Maybe, instead of pretending that a currently-designed database can be ‘Hekatonized’ with a few mouse clicks, we should redesign databases for SQL 2014 to replace table variables with Hekaton tables, exploiting this technology for fast intermediate processing, and for the most part forget, for now, the idea of trying to convert our base relational tables into Hekaton tables. Few database developers would be averse to having their working tables running an order of magnitude faster, as long as it didn’t compromise the integrity of the data in the base tables.

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  • Does anybody know of any resources to achieve this particular "2.5D" isometric engine effect?

    - by Craig Whitley
    I understand this is a little vague, but I was hoping somebody might be able to describe a high-level workflow or link to a resource to be able to achieve a specific isometric "2.5D" tile engine effect. I fell in love with http://www.youtube.com/watch?v=-Q6ISVaM5Ww this engine. Especially with the lighting and the shaders! He has a brief description of how he achieved what he did, but I could really use a brief flow of where you would start, what you would read up on and learn and the logical order to implement these things. A few specific questions: 1) Is there a heightmap on the ground texture that lets the light reflect brighter on certain parts of it? 2) "..using a special material which calculates the world-space normal vectors of every pixel.." - is this some "magic" special material he has created himself, or can you hazard a guess at what he means? 3) with relation to the above quote - what does he mean by 'world-space normal vectors of every pixel'? 4) I'm guessing I'm being a little bit optimistic when I ask if there's any 'all-in-one' tutorial out there? :)

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