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• Cloud Backup: Getting the Users' Backs Up

  - by Tony Davis

  On Wednesday last week, Microsoft announced that as of July 1, all data transfers into its Microsoft Azure cloud will be free (though you have to pay for transferring data out). On Thursday last week, SQL Azure in Western Europe went down. It was a relatively short outage, but since SQL Azure currently provides no easy way to take a standard backup of a database and store it locally, many people had no recourse but to wait patiently for their cloud-based app to resume. It seems that Microsoft are very keen encourage developers to move their data onto their cloud, but are developers ready to do it, given that such basic backup capabilities are lacking? Recently on Simple-Talk, Mike Mooney described a perfect use case for the Microsoft Cloud. They had a simple web-based application with a SQL Server backend; they could move the application to Windows Azure, and the data into SQL Azure and in the process free themselves from much of the hassle surrounding management and scaling of the hardware, network and so on. It was a great fit and yet it nearly didn't happen; lack of support for the BACKUP command almost proved a show-stopper. Of course, backups of Azure databases are always and have always been taken automatically, for disaster recovery purposes, but these are strictly on-cloud copies and as of now it is not possible to use them to them to restore a database to a particular point in time. It seems that none of those clever Microsoft people managed to predict the need to perform basic backups of Azure databases so that copies could be stored locally, outside the Azure universe. At the very least, as Mike points out, performing a local backup before a new deployment is more or less mandatory. Microsoft did at least note the sound of gnashing teeth and, as a stop-gap measure, offered SQL Azure Database Copy which basically allows you to create an online clone of your database, but this doesn't allow for storing local archives of the data. To that end MS has provided SQL Azure Import/Export, to package up and export a database and its data, using BACPACs. These BACPACs do not guarantee transactional consistency; for example, if a child table is modified after the parent is copied, then the copied database will be in inconsistent state (meaning, to add to the fun, BACPACs need to be created from a database copy). In any event, widespread problems with BACPAC's evil cousin, the DACPAC have been well-documented, and it seems likely that many will also give BACPAC the bum's rush. Finally, in a TechEd 2011 presentation tagged "SQL Azure Advanced Administration", it was announced that "backup and restore" were coming in the next SQL Azure CTP. And yet this still doesn't mean that we'll get simple backups as DBAs know and love them. What it does mean, at least, is the ability to restore any given database to a point in time within a 2-week window. For the time being, if you want a local copy of your data and don't want to brave the BACPAC, one is left with SSIS or BCP, creative use of schema and data comparison tools, or use of SQL Azure Backup (currently in beta) in order to perform this simple but vital task. Cheers, Tony.

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• Protecting Consolidated Data on Engineered Systems

  - by Steve Enevold

  In this time of reduced budgets and cost cutting measures in Federal, State and Local governments, the requirement to provide services continues to grow. Many agencies are looking at consolidating their infrastructure to reduce cost and meet budget goals. Oracle's engineered systems are ideal platforms for accomplishing these goals. These systems provide unparalleled performance that is ideal for running applications and databases that traditionally run on separate dedicated environments. However, putting multiple critical applications and databases in a single architecture makes security more critical. You are putting a concentrated set of sensitive data on a single system, making it a more tempting target.  The environments were previously separated by iron so now you need to provide assurance that one group, department, or application's information is not visible to other personnel or applications resident in the Exadata system. Administration of the environments requires formal separation of duties so an administrator of one application environment cannot view or negatively impact others. Also, these systems need to be in protected environments just like other critical production servers. They should be in a data center protected by physical controls, network firewalls, intrusion detection and prevention, etc Exadata also provides unique security benefits, including a reducing attack surface by minimizing packages and services to only those required. In addition to reducing the possible system areas someone may attempt to infiltrate, Exadata has the following features: 1.    Infiniband, which functions as a secure private backplane 2.    IPTables  to perform stateful packet inspection for all nodes               Cellwall implements firewall services on each cell using IPTables 3.    Hardware accelerated encryption for data at rest on storage cells Oracle is uniquely positioned to provide the security necessary for implementing Exadata because security has been a core focus since the company's beginning. In addition to the security capabilities inherent in Exadata, Oracle security products are all certified to run in an Exadata environment. Database Vault Oracle Database Vault helps organizations increase the security of existing applications and address regulatory mandates that call for separation-of-duties, least privilege and other preventive controls to ensure data integrity and data privacy. Oracle Database Vault proactively protects application data stored in the Oracle database from being accessed by privileged database users. A unique feature of Database Vault is the ability to segregate administrative tasks including when a command can be executed, or that the DBA can manage the health of the database and objects, but may not see the data Advanced Security  helps organizations comply with privacy and regulatory mandates by transparently encrypting all application data or specific sensitive columns, such as credit cards, social security numbers, or personally identifiable information (PII). By encrypting data at rest and whenever it leaves the database over the network or via backups, Oracle Advanced Security provides the most cost-effective solution for comprehensive data protection. Label Security  is a powerful and easy-to-use tool for classifying data and mediating access to data based on its classification. Designed to meet public-sector requirements for multi-level security and mandatory access control, Oracle Label Security provides a flexible framework that both government and commercial entities worldwide can use to manage access to data on a "need to know" basis in order to protect data privacy and achieve regulatory compliance  Data Masking reduces the threat of someone in the development org taking data that has been copied from production to the development environment for testing, upgrades, etc by irreversibly replacing the original sensitive data with fictitious data so that production data can be shared safely with IT developers or offshore business partners  Audit Vault and Database Firewall Oracle Audit Vault and Database Firewall serves as a critical detective and preventive control across multiple operating systems and database platforms to protect against the abuse of legitimate access to databases responsible for almost all data breaches and cyber attacks.  Consolidation, cost-savings, and performance can now be achieved without sacrificing security. The combination of built in protection and Oracle’s industry-leading data protection solutions make Exadata an ideal platform for Federal, State, and local governments and agencies.

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• New R Interface to Oracle Data Mining Available for Download

  - by charlie.berger

    The R Interface to Oracle Data Mining ( R-ODM) allows R users to access the power of Oracle Data Mining's in-database functions using the familiar R syntax. R-ODM provides a powerful environment for prototyping data analysis and data mining methodologies. R-ODM is especially useful for: Quick prototyping of vertical or domain-based applications where the Oracle Database supports the application Scripting of "production" data mining methodologies Customizing graphics of ODM data mining results (examples: classification, regression, anomaly detection) The R-ODM interface allows R users to mine data using Oracle Data Mining from the R programming environment. It consists of a set of function wrappers written in source R language that pass data and parameters from the R environment to the Oracle RDBMS enterprise edition as standard user PL/SQL queries via an ODBC interface. The R-ODM interface code is a thin layer of logic and SQL that calls through an ODBC interface. R-ODM does not use or expose any Oracle product code as it is completely an external interface and not part of any Oracle product. R-ODM is similar to the example scripts (e.g., the PL/SQL demo code) that illustrates the use of Oracle Data Mining, for example, how to create Data Mining models, pass arguments, retrieve results etc. R-ODM is packaged as a standard R source package and is distributed freely as part of the R environment's Comprehensive R Archive Network (CRAN). For information about the R environment, R packages and CRAN, see www.r-project.org. R-ODM is particularly intended for data analysts and statisticians familiar with R but not necessarily familiar with the Oracle database environment or PL/SQL. It is a convenient environment to rapidly experiment and prototype Data Mining models and applications. Data Mining models prototyped in the R environment can easily be deployed in their final form in the database environment, just like any other standard Oracle Data Mining model. What is R? R is a system for statistical computation and graphics. It consists of a language plus a run-time environment with graphics, a debugger, access to certain system functions, and the ability to run programs stored in script files. The design of R has been heavily influenced by two existing languages: Becker, Chambers & Wilks' S and Sussman's Scheme. Whereas the resulting language is very similar in appearance to S, the underlying implementation and semantics are derived from Scheme. R was initially written by Ross Ihaka and Robert Gentleman at the Department of Statistics of the University of Auckland in Auckland, New Zealand. Since mid-1997 there has been a core group (the "R Core Team") who can modify the R source code archive. Besides this core group many R users have contributed application code as represented in the near 1,500 publicly-available packages in the CRAN archive (which has shown exponential growth since 2001; R News Volume 8/2, October 2008). Today the R community is a vibrant and growing group of dozens of thousands of users worldwide. It is free software distributed under a GNU-style copyleft, and an official part of the GNU project ("GNU S"). Resources: R website / CRAN R-ODM

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• C++ property system interface for game editors (reflection system)

  - by Cristopher Ismael Sosa Abarca

  I have designed an reusable game engine for an project, and their functionality is like this: Is a completely scripted game engine instead of the usual scripting languages as Lua or Python, this uses Runtime-Compiled C++, and an modified version of Cistron (an component-based programming framework).to be compatible with Runtime-Compiled C++ and so on. Using the typical GameObject and Component classes of the Component-based design pattern, is serializable via JSON, BSON or Binary useful for selecting which objects will be loaded the next time. The main problem: We want to use our custom GameObjects and their components properties in our level editor, before used hardcoded functions to access GameObject base class virtual functions from the derived ones, if do you want to modify an property specifically from that class you need inside into the code, this situation happens too with the derived classes of Component class, in little projects there's no problem but for larger projects becomes tedious, lengthy and error-prone. I've researched a lot to find a solution without luck, i tried with the Ogitor's property system (since our engine is Ogre-based) but we find it inappropiate for the component-based design and it's limited only for the Ogre classes and can lead to performance overhead, and we tried some code we find in the Internet we tested it and worked a little but we considered the macro and lambda abuse too horrible take a look (some code omitted): IWE_IMPLEMENT_PROP_BEGIN(CBaseEntity) IWE_PROP_LEVEL_BEGIN("Editor"); IWE_PROP_INT_S("Id", "Internal id", m_nEntID, [](int n) {}, true); IWE_PROP_LEVEL_END(); IWE_PROP_LEVEL_BEGIN("Entity"); IWE_PROP_STRING_S("Mesh", "Mesh used for this entity", m_pModelName, [pInst](const std::string& sModelName) { pInst->m_stackMemUndoType.push(ENT_MEM_MESH); pInst->m_stackMemUndoStr.push(pInst->getModelName()); pInst->setModel(sModelName, false); pInst->saveState(); }, false); IWE_PROP_VECTOR3_S("Position", m_vecPosition, [pInst](float fX, float fY, float fZ) { pInst->m_stackMemUndoType.push(ENT_MEM_POSITION); pInst->m_stackMemUndoVec3.push(pInst->getPosition()); pInst->saveState(); pInst->m_vecPosition.Get()[0] = fX; pInst->m_vecPosition.Get()[1] = fY; pInst->m_vecPosition.Get()[2] = fZ; pInst->setPosition(pInst->m_vecPosition); }, false); IWE_PROP_QUATERNION_S("Orientation (Quat)", m_quatOrientation, [pInst](float fW, float fX, float fY, float fZ) { pInst->m_stackMemUndoType.push(ENT_MEM_ROTATE); pInst->m_stackMemUndoQuat.push(pInst->getOrientation()); pInst->saveState(); pInst->m_quatOrientation.Get()[0] = fW; pInst->m_quatOrientation.Get()[1] = fX; pInst->m_quatOrientation.Get()[2] = fY; pInst->m_quatOrientation.Get()[3] = fZ; pInst->setOrientation(pInst->m_quatOrientation); }, false); IWE_PROP_LEVEL_END(); IWE_IMPLEMENT_PROP_END() We are finding an simplified way to this, without leading confusing the programmers, (will be released to the public) i find ways to achieve this but they are only available for the common scripting as Lua or editors using C#. also too portable, we can write "wrappers" for different GUI toolkits as Qt or GTK, also i'm thinking to using Boost.Wave to get additional macro functionality without creating my own compiler. The properties designed to use in the editor they are removed in the game since the save file contains their data and loads it using an simple 'load' function to reduce unnecessary code bloat may will be useful if some GameObject property wants to be hidden instead. In summary, there's a way to implement an reflection(property) system for a level editor based in properties from derived classes? Also we can use C++11 and Boost (restricted only to Wave and PropertyTree)

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• A story of Murphy&ndash;my technical issues at TechDays Switzerland #chtd

  - by Laurent Bugnion

  I had two sessions at the recent Swiss TechDays. While the first one (Advanced Development for Windows Phone 8) went extremely well (I think), I had a very annoying technical issue in the beginning of my second session. First let me add that I talked to Microsoft about that and I hope they will change a few things in the room assignment for next year. My two sessions were one right after the other, with only 15 minutes break to change room. I don’t mind having two sessions so close from each other, but I would really like them to be in the same room in order to avoid having to move my laptops (plural, that will become important later) and redoing the tech check. That being said, I am guilty of not checking where my talks would be before the day before the conference, and when I did notice, it was too late to change it. After my first session, I quickly moved to the other room and setup my main laptop, a Dell Precision. We tested the video output (VGA) and didn’t notice anything special. The projectors are using a fairly high resolution (kudos to the Basel conference center for not having old school 1024x768 projectors anymore, that makes Blend really hard to demo ;) but since everything went great during the first talk, I was not worried. In fact I even had some time to chat with some early attendees about my Microsoft Surface and the Samsung Slate 7, which I had carried with me in addition to the Precision. I just thought it would be nice to show the hardware that Windows 8 can run on, without thinking any further. When the session started, I immediately noticed that the main screen was not showing anything. I thought I had just forgotten to switch to “duplicate” for the video output, and did that with a quick Win-P. However it didn’t “hold”. After 2 seconds, it reverted back to a black display for my attendees. Then I started to really worry. We tried everything, switching from VGA to HDMI, changing the resolution, setting the projector as primary display, but nothing did the trick. The projector was just refusing to show my screen. Now, to show you how despaired I started to be, I even considered using the “extend” setting (which worked just fine), and to use one of the feedback monitors on the floor but really it was super cumbersome. Eventually, my last resort arrived: I started my Samsung Slate 7, which by chance has Visual Studio 12 and Blend 5 installed, plugged the HDMI projector in the dock (yes, I had the dock with me, which I usually don’t!), connected it to internet (had to enter a long password for that), loaded the source code from my main machine using a USB stick and…. finally started to give my presentation. All in all I think we lost about 10 minutes. Amongst the most horrible minutes of my whole life, truly (yes I am blessed, I didn’t have that many horrible minutes in my life ;) I really want to apologize to my attendees. We joked a bit during the attempts to resolve the issue, the reactions I had after the session were all very nice and sympathetic. Only a handful of people left my session while I was having the issues, and I really don’t blame them (who knew how long the problem would last!!). But still, I probably talked at more than 60 sessions over the years, and this was by far my most painful moment. What did I learn? So what did I learn from this? Well from now on I will always have my slate ready with the latest source code, internet connection and every tool I might need during the presentation. This way, if I detect even a hint that the Precision might not work, I will just switch to the Slate. The experience of presenting on the slate is actually not bad at all, it is just a bit slow for my taste, but it does work. By the way, I will be posting the code and slides for my sessions very soon, I just need to “clean it and zip it”. Stay tuned, and thanks again for your patience in that horrible circumstance. Cheers Laurent   Laurent Bugnion (GalaSoft) Subscribe | Twitter | Facebook | Flickr | LinkedIn

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• Ask HTG: How Can I Check the Age of My Windows Installation?

  - by Jason Fitzpatrick

  Curious about when you installed Windows and how long you’ve been chugging along without a system refresh? Read on as we show you a simple way to see how long-in-the-tooth your Windows installation is. Dear How-To Geek, It feels like it has been forever since I installed Windows 7 and I’m starting to wonder if some of the performance issues I’m experiencing have something to do with how long ago it was installed. It isn’t crashing or anything horrible, mind you, it just feels slower than it used to and I’m wondering if I should reinstall it to wipe the slate clean. Is there a simple way to determine the original installation date of Windows on its host machine? Sincerely, Worried in Windows Although you only intended to ask one question, you actually asked two. Your direct question is an easy one to answer (how to check the Windows installation date). The indirect question is, however, a little trickier (if you need to reinstall Windows to get a performance boost). Let’s start off with the easy one: how to check your installation date. Windows includes a handy little application just for the purposes of pulling up system information like the installation date, among other things. Open the Start Menu and type cmd in the run box (or, alternatively, press WinKey+R to pull up the run dialog and enter the same command). At the command prompt, type systeminfo.exe Give the application a moment to run; it takes around 15-20 seconds to gather all the data. You’ll most likely need to scroll back up in the console window to find the section at the top that lists operating system stats. What you care about is Original Install Date: We’ve been running the machine we tested the command on since August 23 2009. For the curious, that’s one month and a day after the initial public release of Windows 7 (after we were done playing with early test releases and spent a month mucking around in the guts of Windows 7 to report on features and flaws, we ran a new clean installation and kept on trucking). Now, you might be asking yourself: Why haven’t they reinstalled Windows in all that time? Haven’t things slowed down? Haven’t they upgraded hardware? The truth of the matter is, in most cases there’s no need to completely wipe your computer and start from scratch to resolve issues with Windows and, if you don’t bog your system down with unnecessary and poorly written software, things keep humming along. In fact, we even migrated this machine from a traditional mechanical hard drive to a newer solid-state drive back in 2011. Even though we’ve tested piles of software since then, the machine is still rather clean because 99% of that testing happened in a virtual machine. That’s not just a trick for technology bloggers, either, virtualizing is a handy trick for anyone who wants to run a rock solid base OS and avoid the bog-down-and-then-refresh cycle that can plague a heavily used machine. So while it might be the case that you’ve been running Windows 7 for years and heavy software installation and use has bogged your system down to the point a refresh is in order, we’d strongly suggest reading over the following How-To Geek guides to see if you can’t wrangle the machine into shape without a total wipe (and, if you can’t, at least you’ll be in a better position to keep the refreshed machine light and zippy): HTG Explains: Do You Really Need to Regularly Reinstall Windows? PC Cleaning Apps are a Scam: Here’s Why (and How to Speed Up Your PC) The Best Tips for Speeding Up Your Windows PC Beginner Geek: How to Reinstall Windows on Your Computer Everything You Need to Know About Refreshing and Resetting Your Windows 8 PC Armed with a little knowledge, you too can keep a computer humming along until the next iteration of Windows comes along (and beyond) without the hassle of reinstalling Windows and all your apps.         

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• Microsoft Build 2012 Day 1 Keynote Summary

  - by Tim Murphy

  So I have finally dried the tears after watching the Keynote for Build 2012.  This wasn’t because it was an emotional presentation, but because for the second year I missed the goodies.  Each on site attendee got a Surface RT, a Lumia 920 and a voucher for 100GB of SkyDrive storage. The event was opened with the announcement that in the three days since the launch of Windows 8 over 4 million upgrades have been sold.  I don’t care who you are that is an impressive stat.  Ballmer then spent a fair amount of time remaking the case for the Windows and Windows Phone platforms similar to what we have heard over the last to launch events. There were some cool, but non-essential demos.  The one that was the most fun was the Perceptive Pixel 82” slate device.  At first glance I wondered why I would ever want such a device, but then Ballmer explained it’s possible use for schools and boardrooms.  The actually made sense. Then things got strange.  Steve started explaining features that developers could leverage.  Usually this type of information is left to the product leads.  He focused on the integration with the Charms features such as Search and Share. Steve “Guggs” Guggenheim showed off an app that would appeal to my kids from Disney called “Agent P” which is base on Phineas and Ferb.  Then he got to the meat of the presentation.  We found out that you could add a tile that can be used to sell ad space.  In the same vein we also found out that you could use Microsoft’s, Paypal’s or any commerce engine of your own creation or choosing. For those who are interested in sports and especially developing sports apps you would have found the small presentation from Michael Bayle of ESPN.  He introduced the ESPN app which has tons of features.  For the developers in the crowd he also mentioned that ESPN has an API available at developer.espn.com. During the launch events we were told apps were coming.  In this presentation we were actually shown a scrolling list of logos and told about a couple of them.  Ballmer mentioned specifically Twitter, SAP and DropBox.  These are impressive names that were just a couple of the list impressive names. Steve Ballmer addressed the question of why you should develop for the Windows 8 platform.  He feels that Microsoft has the best commercial terms for developers, a better way to build apps than other platforms and a variety of form factors.  His key point though was the available volume of customers given the current Windows install base and assuming even a flat growth of the platform.  This he backed with a promise that Microsoft is going to do better at marketing and you won’t be able to avoid the ads that they are bringing out. The last section of the key note was present by Kevin Gallo from the Windows Phone team.  This was the real reason I tuned into the webcast.  He impressed upon those watching that the strength of developing for the Microsoft platform is the common programming model that now exist.  While there are difference between form factor implementations you can leverage code across them. He claimed that 90% of developer requests for Windows Phone 8 had been implemented.  These include: More controls with better performance Better live tiles including lock screen integration Speech support in custom apps Easier submission to the market place App camera integration VOIP and chat support Bluetooth and NFC support Native C++ development Direct 3D development   The quote from Kevin that stood out for me was that “Take your Dramamine and buckle your seatbelt type of games are coming to Windows Phone 8”.  He back this up by displaying a list of game development frameworks and then having Unity come out and do a demo. Ok, almost done … The last two things of note for me were the announcement that the SDK is immediately available at dev.windowsphone.com and that they were reducing the cost of an individual developer account to $8 for the next 8 days. Let the development commence. del.icio.us Tags: Build 2012,Windows 8,Windows Phone 8,Windows Phone

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• Ti Launchpad

  - by raysmithequip

  Just thought I would get a couple of notes up here for reference to anyone that is interested...it is now Feb 2011 and I have not been posting here enough to remember this blog. Back in Nov 2010 I ordered the Ti launchpad msp430, it is a little target board kit replete with a mini USB cable, two very inexpensive programmable mcu's and a couple of pin headers with a couple of led's on board, a spi connector some on board jumpers and two programmable micro switches....all for less than $5.00...INCLUDING SHIPPING!!....not bad when the ardruino's are running around 20.00 for the target board, atmega328 and cable off of eBay...I wont even mention the microchip pic right now.  Naw, for $5.00 the Ti launchpad kit is about the cheapest fun around...if-uns your a geek that is... Well, the launchpad was backordered for almost two months, came like Xmas eve in fact...I had almost forgotten it!! And really, it was way late and not my idea of an Xmas present for myself.  That would of been the web expressions 4 I bought a few weeks back.  With all the holidays, I did not even look at it till last week, in fact I passed the wrapped board around at my local ham club meeting during points of personal privilege....some oh's and ahhs but mostly duhs...I actually ordered it to avoid downloading the huge code compressor studio 4 (CCS) that was supposed to be included on the cd.  No cd.  I had already downloaded IAR  another programming IDE for these little micro bugs. In my spare time I toyed with IAR and the launchpad board but after about two days of playing delete the driver with windows I decided to just download CCS 4, the code limited version, and give that a shot......CCS 4, is a good rewrite from the earlier versions, it is based on Eclipse as an IDE and includes the drivers for the msp430 target board I received in the kit.  Once installed I quickly configured the debugger for the target chip which was already plugged into the dip socket at the factory, msp430G2131 from he drop down list and clicked ok...I was in!! The CCS4 is full of bells and whistles compared to the IAR, which I would of preferred for the simplicity.  But the code compressor studio really does have it all!!..the code limited version is free, and of all things will give you java script editor box.  The whole layout in debugger mode reminds me of any modern programmer IDE...I mean sure give me Tex anytime but you simply must admire all the boxes and options included in the GUI.  It was a simple matter to check the assembly code in the flash and ram memory that came preloaded for the launchpad kit.  Assembly.  I am right now looking for my old assembly textbooks...sure I remember how to use mov and add etc but a couple of the commands are a little more than vague anymore.  Still, these little mcu's are about 50 cents each and might just work in a couple of projects I have lined up for the near future.  I may document the code here.  Luckily, I plan to write the code in c++ for the main project but if it has to be assembly, no prob.  For reference, the program that came already on the 2131 in the kit was a temperature indicator that alternately flashed red and green leds and changed the intensity of either depending on whether the temp was rising or falling...neat.  Neat enough that it might be worthwhile banging out a little GUI in windows 7 to test the new user device system calls, maybe put a temp gauge widget up on the desktop...just to keep from getting bored.  If you see some assembly code on this blog, you know I was doing something with one of the many mcu's out there.....thats all for now, more to follow...a bit later, of course.

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• RPi and Java Embedded GPIO: Big Data and Java Technology

  - by hinkmond

  Java Embedded and Big Data go hand-in-hand, especially as demonstrated by prototyping on a Raspberry Pi to show how well the Java Embedded platform can perform on a small embedded device which then becomes the proof-of-concept for industrial controllers, medical equipment, networking gear or any type of sensor-connected device generating large amounts of data. The key is a fast and reliable way to access that data using Java technology. In the previous blog posts you've seen the integration of a static electricity sensor and the Raspberry Pi through the GPIO port, then accessing that data through Java Embedded code. It's important to point out how this works and why it works well with Java code. First, the version of Linux (Debian Wheezy/Raspian) that is found on the RPi has a very convenient way to access the GPIO ports through the use of Linux OS managed file handles. This is key in avoiding terrible and complex coding using register manipulation in C code, or having to program in a less elegant and clumsy procedural scripting language such as python. Instead, using Java Embedded, allows a fast way to access those GPIO ports through those same Linux file handles. Java already has a very easy to program way to access file handles with a high degree of performance that matches direct access of those file handles with the Linux OS. Using the Java API java.io.FileWriter lets us open the same file handles that the Linux OS has for accessing the GPIO ports. Then, by first resetting the ports using the unexport and export file handles, we can initialize them for easy use in a Java app. // Open file handles to GPIO port unexport and export controls FileWriter unexportFile = new FileWriter("/sys/class/gpio/unexport"); FileWriter exportFile = new FileWriter("/sys/class/gpio/export"); ... // Reset the port unexportFile.write(gpioChannel); unexportFile.flush(); // Set the port for use exportFile.write(gpioChannel); exportFile.flush(); Then, another set of file handles can be used by the Java app to control the direction of the GPIO port by writing either "in" or "out" to the direction file handle. // Open file handle to input/output direction control of port FileWriter directionFile = new FileWriter("/sys/class/gpio/gpio" + gpioChannel + "/direction"); // Set port for input directionFile.write("in"); // Or, use "out" for output directionFile.flush(); And, finally, a RandomAccessFile handle can be used with a high degree of performance on par with native C code (only milliseconds to read in data and write out data) with low overhead (unlike python) to manipulate the data going in and out on the GPIO port, while the object-oriented nature of Java programming allows for an easy way to construct complex analytic software around that data access functionality to the external world. RandomAccessFile[] raf = new RandomAccessFile[GpioChannels.length]; ... // Reset file seek pointer to read latest value of GPIO port raf[channum].seek(0); raf[channum].read(inBytes); inLine = new String(inBytes); It's Big Data from sensors and industrial/medical/networking equipment meeting complex analytical software on a small constraint device (like a Linux/ARM RPi) where Java Embedded allows you to shine as an Embedded Device Software Designer. Hinkmond

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• Why do I need two Instances in Windows Azure?

  - by BuckWoody

  Windows Azure as a Platform as a Service (PaaS) means that there are various components you can use in it to solve a problem: Compute “Roles” - Computers running an OS and optionally IIS - you can have more than one "Instance" of a given Role Storage - Blobs, Tables and Queues for Storage Other Services - Things like the Service Bus, Azure Connection Services, SQL Azure and Caching It’s important to understand that some of these services are Stateless and others maintain State. Stateless means (at least in this case) that a system might disappear from one physical location and appear elsewhere. You can think of this as a cashier at the front of a store. If you’re in line, a cashier might take his break, and another person might replace him. As long as the order proceeds, you as the customer aren’t really affected except for the few seconds it takes to change them out. The cashier function in this example is stateless. The Compute Role Instances in Windows Azure are Stateless. To upgrade hardware, because of a fault or many other reasons, a Compute Role's Instance might stop on one physical server, and another will pick it up. This is done through the controlling fabric that Windows Azure uses to manage the systems. It’s important to note that storage in Azure does maintain State. Your data will not simply disappear - it is maintained - in fact, it’s maintained three times in a single datacenter and all those copies are replicated to another for safety. Going back to our example, storage is similar to the cash register itself. Even though a cashier leaves, the record of your payment is maintained. So if a Compute Role Instance can disappear and re-appear, the things running on that first Instance would stop working. If you wrote your code in a Stateless way, then another Role Instance simply re-starts that transaction and keeps working, just like the other cashier in the example. But if you only have one Instance of a Role, then when the Role Instance is re-started, or when you need to upgrade your own code, you can face downtime, since there’s only one. That means you should deploy at least two of each Role Instance not only for scale to handle load, but so that the first “cashier” has someone to replace them when they disappear. It’s not just a good idea - to gain the Service Level Agreement (SLA) for our uptime in Azure it’s a requirement. We point this out right in the Management Portal when you deploy the application: (Click to enlarge) When you deploy a Role Instance you can also set the “Upgrade Domain”. Placing Roles on separate Upgrade Domains means that you have a continuous service whenever you upgrade (more on upgrades in another post) - the process looks like this for two Roles. This example covers the scenario for upgrade, so you have four roles total - One Web and one Worker running the "older" code, and one of each running the new code. In all those Roles you want at least two instances, and this example shows that you're covered for High Availability and upgrade paths: The take-away is this - always plan for forward-facing Roles to have at least two copies. For Worker Roles that do background processing, there are ways to architect around this number, but it does affect the SLA if you have only one.

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• SQL Server IO handling mechanism can be severely affected by high CPU usage

  - by sqlworkshops

  Are you using SSD or SAN / NAS based storage solution and sporadically observe SQL Server experiencing high IO wait times or from time to time your DAS / HDD becomes very slow according to SQL Server statistics? Read on… I need your help to up vote my connect item – https://connect.microsoft.com/SQLServer/feedback/details/744650/sql-server-io-handling-mechanism-can-be-severely-affected-by-high-cpu-usage. Instead of taking few seconds, queries could take minutes/hours to complete when CPU is busy.In SQL Server when a query / request needs to read data that is not in data cache or when the request has to write to disk, like transaction log records, the request / task will queue up the IO operation and wait for it to complete (task in suspended state, this wait time is the resource wait time). When the IO operation is complete, the task will be queued to run on the CPU. If the CPU is busy executing other tasks, this task will wait (task in runnable state) until other tasks in the queue either complete or get suspended due to waits or exhaust their quantum of 4ms (this is the signal wait time, which along with resource wait time will increase the overall wait time). When the CPU becomes free, the task will finally be run on the CPU (task in running state).The signal wait time can be up to 4ms per runnable task, this is by design. So if a CPU has 5 runnable tasks in the queue, then this query after the resource becomes available might wait up to a maximum of 5 X 4ms = 20ms in the runnable state (normally less as other tasks might not use the full quantum).In case the CPU usage is high, let’s say many CPU intensive queries are running on the instance, there is a possibility that the IO operations that are completed at the Hardware and Operating System level are not yet processed by SQL Server, keeping the task in the resource wait state for longer than necessary. In case of an SSD, the IO operation might even complete in less than a millisecond, but it might take SQL Server 100s of milliseconds, for instance, to process the completed IO operation. For example, let’s say you have a user inserting 500 rows in individual transactions. When the transaction log is on an SSD or battery backed up controller that has write cache enabled, all of these inserts will complete in 100 to 200ms. With a CPU intensive parallel query executing across all CPU cores, the same inserts might take minutes to complete. WRITELOG wait time will be very high in this case (both under sys.dm_io_virtual_file_stats and sys.dm_os_wait_stats). In addition you will notice a large number of WAITELOG waits since log records are written by LOG WRITER and hence very high signal_wait_time_ms leading to more query delays. However, Performance Monitor Counter, PhysicalDisk, Avg. Disk sec/Write will report very low latency times.Such delayed IO handling also occurs to read operations with artificially very high PAGEIOLATCH_SH wait time (with number of PAGEIOLATCH_SH waits remaining the same). This problem will manifest more and more as customers start using SSD based storage for SQL Server, since they drive the CPU usage to the limits with faster IOs. We have a few workarounds for specific scenarios, but we think Microsoft should resolve this issue at the product level. We have a connect item open – https://connect.microsoft.com/SQLServer/feedback/details/744650/sql-server-io-handling-mechanism-can-be-severely-affected-by-high-cpu-usage - (with example scripts) to reproduce this behavior, please up vote the item so the issue will be addressed by the SQL Server product team soon.Thanks for your help and best regards,Ramesh MeyyappanHome: www.sqlworkshops.comLinkedIn: http://at.linkedin.com/in/rmeyyappan

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• Booting the liveCD/USB in EFI mode fails on Samsung Tablet XE700T1A

  - by F.L.

  My tablet is Samsung Series 7 Slate (XE700T1A-A02FR (French Language)). It operates an Intel Sandy Bridge architecture. The main issue about this tablet is that it ships with an installed Windows 7 in (U)EFI mode (GPT partition table, etc.), so I'd like to get an EFI dual boot with Ubuntu. But it seems I can't boot on the liveCD in EFI mode. It starts loading (up to initrd), but I then get a blank (black) screen. I've tried the nomodeset kernel option (as well as removing quiet and splash) with no luck. [2012-09-27] I have used the Ubuntu 12.04.1 Desktop ISO (I have read somewhere that it is the only one that can boot in EFI mode). I'd say this has something to do with UEFI since the LiveCD boots in bios mode but not in efi mode. Besides, I am not sure my boot info will help, since I can't boot the LiveCD in EFI mode. As a result I can't install ubuntu in EFI mode. So it would be the boot info from the liveCD boot in bios mode. This happens on a ubuntu-12.04.1-desktop-amd64 iso used on a LiveUSB. Live USB was created by dd'ing the iso onto the full disk device (i.e. /dev/sdx no number) of the Flash drive. I have also tried copying the LiveCD files on a primary GPT partition, but with no luck, I just get the grub shell, no menu, no install option. [2012-09-28] I tried today a flash drive created with Ubuntu's Startup Disk Creator and the alternate 12.04.1 64 bit ISO. I get a grub menu in text mode (which meens it did start in efi mode) with install options / test options. But when I start any of these, I simply get a black screen (no cursor, neither mouse nor text-mode cursor). I tried removing the 'quiet' option and adding nomodeset and acpi=off, but it didn't do any good. So this is the same result as for the LiveCD. [2012-10-01] I have tried with a version of the secure remix version via usb-creator-gtk. The boot on the USB key has the same symptoms. Boot in EFI mode is impossible (I have menu but whatever entry I choose, I get the blank screen problem). The boot in BIOS mode works, I did the install. Then I used boot-repair to try installing grub-efi and get a system that would boot in efi mode. But I can't boot this system, because the EFI firmware doesn't seem to detect that sda contains a valid efi partition. Here is the resulting boot-info Boot info 1253554 [2012-10-01] Today, I have reinstalled the pre-shipped version of windows 7, and then installed ubuntu from a secure-remix iso dumped on USB flash drive vie usb-creator-gtk booted in BIOS mode. When install ended, I said "continue testing" then I used boot-repair to try get the bootloader installed. Now, when I boot the tablet, I get the grub menu, it can chainload windows 7 flawlessly. But when I try to start one of the ubuntu options I get the same old blank screen. Here is the new boot-info: Boot info 1253927 [2012-10-01] I tried installing the 3.3 kernel by chrooting a live usb boot (secure remix again) into the installed system. Same symptoms. I feel the key to this is that the device's efi firmware (which is EFI v2.0) would expose the graphics hardware in a way that prevents the kernel to initialize it, and thus prevents it from booting (the kernel stops all drive access just after the screen turns kind of very dark purple). Here is some info on the UEFI firmware as given by rEFInd: EFI revision: 2.00 Platform: x86_64 (64 bit) Firmware: American Megatrends 4.635 Screen Output: Graphics Output (UEFI), 800x600 [2012-10-08] This week end I tried loading the kernel with elilo. Eventhough I didn't have more luck on booting the kernel, elilo gives more info when loading the kernel. I think the next step is trying to load a kernel with EFI stub directly.

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• Future Of F# At Jazoon 2011

  - by Alois Kraus

  I was at the Jazoon 2011 in Zurich (Switzerland). It was a really cool event and it had many top notch speaker not only from the Microsoft universe. One of the most interesting talks was from Don Syme with the title: F# Today/F# Tomorrow. He did show how to use F# scripting to browse through open databases/, OData Web Services, Sharepoint, …interactively. It looked really easy with the help of F# Type Providers which is the next big language feature in a future F# version. The object returned by a Type Provider is used to access the data like in usual strongly typed object model. No guessing how the property of an object is called. Intellisense will show it just as you expect. There exists a range of Type Providers for various data sources where the schema of the stored data can somehow be dynamically extracted. Lets use e.g. a free database it would be then let data = DbProvider(http://.....); data the object which contains all data from e.g. a chemical database. It has an elements collection which contains an element which has the properties: Name, AtomicMass, Picture, …. You can browse the object returned by the Type Provider with full Intellisense because the returned object is strongly typed which makes this happen. The same can be achieved of course with code generators that use an input the schema of the input data (OData Web Service, database, Sharepoint, JSON serialized data, …) and spit out the necessary strongly typed objects as an assembly. This does work but has the downside that if the schema of your data source is huge you will quickly run against a wall with traditional code generators since the generated “deserialization” assembly could easily become several hundred MB. *** The following part contains guessing how this exactly work by asking Don two questions **** Q: Can I use Type Providers within C#? D: No. Q: F# is after all a library. I can reference the F# assemblies and use the contained Type Providers? D: F# does annotate the generated types in a special way at runtime which is not a static type that C# could use. The F# type providers seem to use a hybrid approach. At compilation time the Type Provider is instantiated with the url of your input data. The obtained schema information is used by the compiler to generate static types as usual but only for a small subset (the top level classes up to certain nesting level would make sense to me). To make this work you need to access the actual data source at compile time which could be a problem if you want to keep the actual url in a config file. Ok so this explains why it does work at all. But in the demo we did see full intellisense support down to the deepest object level. It looks like if you navigate deeper into the object hierarchy the type provider is instantiated in the background and attach to a true static type the properties determined at run time while you were typing. So this type is not really static at all. It is static if you define as a static type that its properties shows up in intellisense. But since this type information is determined while you are typing and it is not used to generate a true static type and you cannot use these “intellistatic” types from C#. Nonetheless this is a very cool language feature. With the plotting libraries you can generate expressive charts from any datasource within seconds to get quickly an overview of any structured data storage. My favorite programming language C# will not get such features in the near future there is hope. If you restrict yourself to OData sources you can use LINQPad to query any OData enabled data source with LINQ with ease. There you can query Stackoverflow with The output is also nicely rendered which makes it a very good tool to explore OData sources today.

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• Growing Talent

  The subtitle of Daniel Coyles intriguing book The Talent Code is Greatness Isnt Born. Its Grown. Heres How. The Talent Code proceeds to layout a theory of how expertise can be cultivated through specific practices that encourage the growth of myelin in the brain. Myelin is a material that is produced and wraps around heavily used circuits in the brain, making them more efficient. Coyle uses an analogy that geeks will appreciate. When a circuit in the brain is used a lot (i.e. a specific action is repeated), the myelin insulates that circuit, increasing its bandwidth from telephone over copper to high speed broadband. This leads to the funny phenomenon of effortless expertise. Although highly skilled, the best players make it look easy. Coyle provides some biological backing for the long held theory that it takes 10,000 hours of practice to achieve mastery over a given subject. 10,000 hours or 10 years, as in, Teach Yourself Programming in Ten Years and others. However, it is not just that more hours equals more mastery. The other factors that Coyle identifies includes deep practice, practice which crucially involves drills that are challenging without being impossible. Another way to put it is that every day you spend doing only tasks you find monotonous and automatic, you are literally stagnating your brains development! Perhaps Coyles subtitle, needs one more phrase, Greatness Isnt Born. Its Grown. Heres How. And oh yeah, its not easy. Challenging yourself, continuing to persist in the face of repeated failures, practicing every day is not easy. As consultants, we sell our expertise, so it makes sense that we plan projects so that people can play to their strengths. At the same time, an important part of our culture is constant improvement, challenging yourself to be better. And the balancing contest ensues. I just finished working on a proof of concept (POC) we did for a project we are bidding on. Completely time boxed, so our team naturally split responsibilities amongst ourselves according to who was better at what. I must have been pretty bad at the other components, as I found myself working on the user interface, not my usual strength. The POC had a website frontend, and one thing I do know is HTML. After starting out in pure ASP.NET WebForms, I got frustrated as time was ticking, I knew what I wanted in HTML, but I couldnt coax the right output out of the ASP.NET controls. I needed two or three elements on the screen that were identical in layout, with different content. With a backup plan in  of writing the HTML into the response by hand, I decided to challenge myself a bit and see what I could do in an hour or two using the Microsoft submitted jQuery micro-templating JavaScript library. This risk paid off. I was able to quickly get the user interface up and running, responsive to the JSON data we were working with. I felt energized by the double win of getting the POC ready and learning something new. Opportunities  specifically like this POC dont come around often, but the takeaway is that while it wont be easy, there are ways to generate your own opportunities to grow towards greatness.Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• Open a File Browser From Your Current Command Prompt/Terminal Directory

  - by The Geek

  Ever been doing some work at the command line when you realized… it would be a lot easier if I could just use the mouse for this task? One command later, you’ll have a window open to the same place that you’re at. This same tip works in more than one operating system, so we’ll detail how to do it in every way we know how. Open a File Browser in Windows We’ve actually covered this before when we told you how to open an Explorer window from the command prompt’s current directory, but we’ll briefly review: Just type the follow command into your command prompt: explorer . Note: You could actually just type “start .” instead. And you’ll then see a file browsing window set to the same directory you were previous at. And yes, this screenshot is from Vista, but it works the same in every version of Windows. If that wasn’t good enough, you should really read how you can navigate in the File Open/Save dialogs with just the keyboard—now that’s a Stupid Geek Trick! Open a File Browser in Linux For this exercise, we’re going to assume that you’re using Gnome under a Linux flavor like Ubuntu, because that’s the most common. From your terminal window, just type in the following command: nautilus . And the next thing you know, you’ll have a file browser window open at the current location. You’ll see some type of error message at the prompt, but you can pretty much ignore that. You can also use “gnome-open .” if you want. Open Finder in Mac OS X All the Mac computers in this office are running Linux, so we haven’t had a chance to verify, but you should be able to use the following command on OS X to open Finder in the current terminal location: open . Open Dolphin on Linux KDE4 dolphin . Got any extra tips to help out your fellow readers? How do you do the same thing in KDE3? What about OS X? Leave your savvy advice in the comments, and maybe we’ll update the article. Or not. Either way, it’ll help somebody! Similar Articles Productive Geek Tips Keyboard Ninja: Concatenate Multiple Text Files in WindowsStupid Geek Tricks: Open an Explorer Window from the Command Prompt’s Current DirectoryHow to automate FTP uploads from the Windows Command LineShell Geek: Rename Multiple Files At OnceAdd "Open with gedit" to the right click menu in Ubuntu 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 DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Home Networks – How do they look like & the problems they cause Check Your IMAP Mail Offline In Thunderbird Follow Finder Finds You Twitter Users To Follow Combine MP3 Files Easily QuicklyCode Provides Cheatsheets & Other Programming Stuff Download Free MP3s from Amazon

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• Learn Many Languages

  - by Phil Factor

  Around twenty-five years ago, I was trying to solve the problem of recruiting suitable developers for a large business. I visited the local University (it was a Technical College then). My mission was to remind them that we were a large, local employer of technical people and to suggest that, as they were in the business of educating young people for a career in IT, we should work together. I anticipated a harmonious chat where we could suggest to them the idea of mentioning our name to some of their graduates. It didn’t go well. The academic staff displayed a degree of revulsion towards the whole topic of IT in the world of commerce that surprised me; tweed met charcoal-grey, trainers met black shoes. However, their antipathy to commerce was something we could have worked around, since few of their graduates were destined for a career as university lecturers. They asked me what sort of language skills we needed. I tried ducking the invidious task of naming computer languages, since I wanted recruits who were quick to adapt and learn, with a broad understanding of IT, including development methodologies, technologies, and data. However, they pressed the point and I ended up saying that we needed good working knowledge of C and BASIC, though FORTRAN and COBOL were, at the time, still useful. There was a ghastly silence. It was as if I’d recommended the beliefs and practices of the Bogomils of Bulgaria to a gathering of Cardinals. They stared at me severely, like owls, until the head of department broke the silence, informing me in clipped tones that they taught only Modula 2. Now, I wouldn’t blame you if at this point you hurriedly had to look up ‘Modula 2′ on Wikipedia. Based largely on Pascal, it was a specialist language for embedded systems, but I’ve never ever come across it in a commercial business application. Nevertheless, it was an excellent teaching language since it taught modules, scope control, multiprogramming and the advantages of encapsulating a set of related subprograms and data structures. As long as the course also taught how to transfer these skills to other, more useful languages, it was not necessarily a problem. I said as much, but they gleefully retorted that the biggest local employer, a defense contractor specializing in Radar and military technology, used nothing but Modula 2. “Why teach any other programming language when they will be using Modula 2 for all their working lives?” said a complacent lecturer. On hearing this, I made my excuses and left. There could be no meeting of minds. They were providing training in a specific computer language, not an education in IT. Twenty years later, I once more worked nearby and regularly passed the long-deserted ‘brownfield’ site of the erstwhile largest local employer; the end of the cold war had led to lean times for defense contractors. A digger was about to clear the rubble of the long demolished factory along with the accompanying growth of buddleia and thistles, in order to lay the infrastructure for ‘affordable housing’. Modula 2 was a distant memory. Either those employees had short working lives or they’d retrained in other languages. The University, by contrast, was thriving, but I wondered if their erstwhile graduates had ever cursed the narrow specialization of their training in IT, as they struggled with the unexpected variety of their subsequent careers.

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• Why are you doing this? [closed]

  - by NIcholas Lawson

  I am working on a story that I am going to be querying to several magazines in my hometown about this work that is being done by the AXR group. This is a group of people who have networked online and are working on developing a higher level syntax structure than CSS and HTML currently offer. I am covering this is as a story because I see potential in this as a human interest story in cosmopolitan society. I have been asked by the group to pose this question to you and would appreciate any and all comments you would have on the following ... To AXR: So when does the internet become finished? At what point does a computer scientist say to himself ... my job here is finished ... the internet is complete? When is the internet ready to be more about the display of content than the uploading of new websites or computer tech? You are embarking on upon a sixty year project every day you work with this internet, what drives you? Why are you spending your hard earned hours working on the code to this computer? I spend thirty hours a week online because I love the writing and I know what would make the internet better ... ease of use ... i know it is difficult to program but I see some very elegant solutions online ... in this early inception phase of your programming development for this HSS prototype ... I would like to know why I do not see you programmers asking questions such as ... What would make the end user's life the easiest when using this code? I know you can solve the problem but an evolution forward would be simple, not simple to a computer scientist but simple to use for a career janitor ... if you could solve the problem of alleviating the stress at using a the computer you could get better content out of the computer ... right now the main problem is that the best content is in the hands of the people least likely to use the computer and the more simple you make the computer to use ... the better the content collection will be in the long run ... That is not what I want to talk about though ... why are you writing code when you could be writing stories? I know the computer is worthless without content so I build content, I know the book is worthless without the combinations of words in them, i know the television is worthless without the television news anchor or the actor, what I want to know from you folks in a very journalistic sense is why are you even bothering to bother to write code for a machine that has only made our lives i would dare say less interesting. why are you feeding the beast your time when you could be writing stories or being an actor or musician or auto mechanic ... why code? why this machine? what do you love about it? what do you hate about it? what do you wonder about it? I want to know so that starting out I know how to further shape my questions with axr ... i want the full story ... i want the real answers ... and i want to know why you are doing this, it would make for great writing if you could elucidate on this point.

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• SQL Server Optimizer Malfunction?

  - by Tony Davis

  There was a sharp intake of breath from the audience when Adam Machanic declared the SQL Server optimizer to be essentially "stuck in 1997". It was during his fascinating "Query Tuning Mastery: Manhandling Parallelism" session at the recent PASS SQL Summit. Paraphrasing somewhat, Adam (blog | @AdamMachanic) offered a convincing argument that the optimizer often delivers flawed plans based on assumptions that are no longer valid with today’s hardware. In 1997, when Microsoft engineers re-designed the database engine for SQL Server 7.0, SQL Server got its initial implementation of a cost-based optimizer. Up to SQL Server 2000, the developer often had to deploy a steady stream of hints in SQL statements to combat the occasionally wilful plan choices made by the optimizer. However, with each successive release, the optimizer has evolved and improved in its decision-making. It is still prone to the occasional stumble when we tackle difficult problems, join large numbers of tables, perform complex aggregations, and so on, but for most of us, most of the time, the optimizer purrs along efficiently in the background. Adam, however, challenged further any assumption that the current optimizer is competent at providing the most efficient plans for our more complex analytical queries, and in particular of offering up correctly parallelized plans. He painted a picture of a present where complex analytical queries have become ever more prevalent; where disk IO is ever faster so that reads from disk come into buffer cache faster than ever; where the improving RAM-to-data ratio means that we have a better chance of finding our data in cache. Most importantly, we have more CPUs at our disposal than ever before. To get these queries to perform, we not only need to have the right indexes, but also to be able to split the data up into subsets and spread its processing evenly across all these available CPUs. Improvements such as support for ColumnStore indexes are taking things in the right direction, but, unfortunately, deficiencies in the current Optimizer mean that SQL Server is yet to be able to exploit properly all those extra CPUs. Adam’s contention was that the current optimizer uses essentially the same costing model for many of its core operations as it did back in the days of SQL Server 7, based on assumptions that are no longer valid. One example he gave was a "slow disk" bias that may have been valid back in 1997 but certainly is not on modern disk systems. Essentially, the optimizer assesses the relative cost of serial versus parallel plans based on the assumption that there is no IO cost benefit from parallelization, only CPU. It assumes that a single request will saturate the IO channel, and so a query would not run any faster if we parallelized IO because the disk system simply wouldn’t be able to handle the extra pressure. As such, the optimizer often decides that a serial plan is lower cost, often in cases where a parallel plan would improve performance dramatically. It was challenging and thought provoking stuff, as were his techniques for driving parallelism through query logic based on subsets of rows that define the "grain" of the query. I highly recommend you catch the session if you missed it. I’m interested to hear though, when and how often people feel the force of the optimizer’s shortcomings. Barring mistakes, such as stale statistics, how often do you feel the Optimizer fails to find the plan you think it should, and what are the most common causes? Is it fighting to induce it toward parallelism? Combating unexpected plans, arising from table partitioning? Something altogether more prosaic? Cheers, Tony.

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• 12.04 making BCM4313 card work with aircrack-ng?

  - by Charles Forest

  I'm a real Linux Noob, just started using it (this month) and until now i had no issues. now i'm trying to set-up aircrack-ng on my laptop, but it seems like it's using the worst card possible (or almost) there is a TON of tutorial on this card (seems to be hell to set-up) i have tryed some, but i ended up uninstalling my drivers, messing with my desktops, and ended by having no more "X" to close my windows (i have no clue how i ended there) i just re-installed my linux (took me 2 hours to setup everything again), but now i'm a bit "Scared" to try tutorials randomly again. Right now it says the driver is wl, wich is not the one i want (AFAIK it's not supported) i'm not sure what kind of informations are needed, but here's what i think could be usefull. lspci -knn 00:00.0 Host bridge [0600]: Intel Corporation 2nd Generation Core Processor Family DRAM Controller [8086:0104] (rev 09) Subsystem: Samsung Electronics Co Ltd Device [144d:c0a5] Kernel driver in use: agpgart-intel 00:01.0 PCI bridge [0604]: Intel Corporation Xeon E3-1200/2nd Generation Core Processor Family PCI Express Root Port [8086:0101] (rev 09) Kernel driver in use: pcieport Kernel modules: shpchp 00:02.0 VGA compatible controller [0300]: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0116] (rev 09) Subsystem: Samsung Electronics Co Ltd Device [144d:c0a5] Kernel driver in use: i915 Kernel modules: i915 00:16.0 Communication controller [0780]: Intel Corporation 6 Series/C200 Series Chipset Family MEI Controller #1 [8086:1c3a] (rev 04) Subsystem: Samsung Electronics Co Ltd Device [144d:c0a5] Kernel driver in use: mei Kernel modules: mei 00:1a.0 USB controller [0c03]: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #2 [8086:1c2d] (rev 04) Subsystem: Samsung Electronics Co Ltd Device [144d:c0a5] Kernel driver in use: ehci_hcd 00:1b.0 Audio device [0403]: Intel Corporation 6 Series/C200 Series Chipset Family High Definition Audio Controller [8086:1c20] (rev 04) Subsystem: Samsung Electronics Co Ltd Device [144d:c0a5] Kernel driver in use: snd_hda_intel Kernel modules: snd-hda-intel 00:1c.0 PCI bridge [0604]: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 1 [8086:1c10] (rev b4) Kernel driver in use: pcieport Kernel modules: shpchp 00:1c.3 PCI bridge [0604]: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 4 [8086:1c16] (rev b4) Kernel driver in use: pcieport Kernel modules: shpchp 00:1c.4 PCI bridge [0604]: Intel Corporation 6 Series/C200 Series Chipset Family PCI Express Root Port 5 [8086:1c18] (rev b4) Kernel driver in use: pcieport Kernel modules: shpchp 00:1d.0 USB controller [0c03]: Intel Corporation 6 Series/C200 Series Chipset Family USB Enhanced Host Controller #1 [8086:1c26] (rev 04) Subsystem: Samsung Electronics Co Ltd Device [144d:c0a5] Kernel driver in use: ehci_hcd 00:1f.0 ISA bridge [0601]: Intel Corporation HM65 Express Chipset Family LPC Controller [8086:1c49] (rev 04) Subsystem: Samsung Electronics Co Ltd Device [144d:c0a5] Kernel modules: iTCO_wdt 00:1f.2 SATA controller [0106]: Intel Corporation 6 Series/C200 Series Chipset Family 6 port SATA AHCI Controller [8086:1c03] (rev 04) Subsystem: Samsung Electronics Co Ltd Device [144d:c0a5] Kernel driver in use: ahci 00:1f.3 SMBus [0c05]: Intel Corporation 6 Series/C200 Series Chipset Family SMBus Controller [8086:1c22] (rev 04) Subsystem: Samsung Electronics Co Ltd Device [144d:c0a5] Kernel modules: i2c-i801 01:00.0 3D controller [0302]: NVIDIA Corporation GF108 [GeForce GT 540M] [10de:0df4] (rev a1) Subsystem: Samsung Electronics Co Ltd Device [144d:c0a5] Kernel driver in use: nouveau Kernel modules: nouveau, nvidiafb WIRELESS CARD 02:00.0 Network controller [0280]: Broadcom Corporation BCM4313 802.11b/g/n Wireless LAN Controller [14e4:4727] (rev 01) Subsystem: Wistron NeWeb Corp. Device [185f:051a] Kernel driver in use: wl Kernel modules: wl, bcma, brcmsmac REST... 03:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller [10ec:8168] (rev 06) Subsystem: Samsung Electronics Co Ltd Device [144d:c0a5] Kernel driver in use: r8169 Kernel modules: r8169 04:00.0 USB controller [0c03]: NEC Corporation uPD720200 USB 3.0 Host Controller [1033:0194] (rev 04) Subsystem: Samsung Electronics Co Ltd Device [144d:c0a5] Kernel driver in use: xhci_hcd Also, if i'm "screwed" with my hardware, just tell me.

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• How should I plan the inheritance structure for my game?

  - by Eric Thoma

  I am trying to write a platform shooter in C++ with a really good class structure for robustness. The game itself is secondary; it is the learning process of writing it that is primary. I am implementing an inheritance tree for all of the objects in my game, but I find myself unsure on some decisions. One specific issue that it bugging me is this: I have an Actor that is simply defined as anything in the game world. Under Actor is Character. Both of these classes are abstract. Under Character is the Philosopher, who is the main character that the user commands. Also under Character is NPC, which uses an AI module with stock routines for friendly, enemy and (maybe) neutral alignments. So under NPC I want to have three subclasses: FriendlyNPC, EnemyNPC and NeutralNPC. These classes are not abstract, and will often be subclassed in order to make different types of NPC's, like Engineer, Scientist and the most evil Programmer. Still, if I want to implement a generic NPC named Kevin, it would nice to be able to put him in without making a new class for him. I could just instantiate a FriendlyNPC and pass some values for the AI machine and for the dialogue; that would be ideal. But what if Kevin is the one benevolent Programmer in the whole world? Now we must make a class for him (but what should it be called?). Now we have a character that should inherit from Programmer (as Kevin has all the same abilities but just uses the friendly AI functions) but also should inherit from FriendlyNPC. Programmer and FriendlyNPC branched away from each other on the inheritance tree, so inheriting from both of them would have conflicts, because some of the same functions have been implemented in different ways on the two of them. 1) Is there a better way to order these classes to avoid these conflicts? Having three subclasses; Friendly, Enemy and Neutral; from each type of NPC; Engineer, Scientist, and Programmer; would amount to a huge number of classes. I would share specific implementation details, but I am writing the game slowly, piece by piece, and so I haven't implemented past Character yet. 2) Is there a place where I can learn these programming paradigms? I am already trying to take advantage of some good design patterns, like MVC architecture and Mediator objects. The whole point of this project is to write something in good style. It is difficult to tell what should become a subclass and what should become a state (i.e. Friendly boolean v. Friendly class). Having many states slows down code with if statements and makes classes long and unwieldy. On the other hand, having a class for everything isn't practical. 3) Are there good rules of thumb or resources to learn more about this? 4) Finally, where does templating come in to this? How should I coordinate templates into my class structure? I have never actually taken advantage of templating honestly, but I hear that it increases modularity, which means good code.

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• What is the best practice, point of view of well experienced developers

  - by Damien MIRAS

  My manager pushes me to use his self defined best practices. All of these practices are based on is own assumptions. I disagree with them and I would like to have some feedback of well experienced people about these practices. I would prefer answers from people involved in the maintenance of huge products and people whom have maintained the product for years. Developers with 15+ years of experience are preferred because my manager has that much experience himself. I have 7 years of experience. Here are the practices he wants me to use: never extends classes, use composition and interface instead because extending classes are unmaintainable and difficult to debug. What I think about that Extend when needed, respect "Liskov's Substitution Principle" and you'll never be stuck with a problem, but prefer composition and decoration. I don't know any serious project which has banned inheriting, sometimes it's impossible to not use that, i.e. in a UI framework. Design patterns are just unusable. In PHP, for simple use cases (for example a user needs a web interface to view a database table), his "best practice" is: copy some random php code wich we own, paste and modify it, put html and php code in same file, never use classes in PHP, it doesn't work well for small jobs, and in fact it doesn't work well at all, there is no good tool to work with. Copy & paste PHP code is good practice for maintenance because scripts are independent, if you have a bug somewhere you can fix it without side effects. What I think about that: NEVER EVER COPY code or do it because you have five minutes to deliver something, you will do some refactoring after that. Copy & paste code is a beginners error, if you have errors you'll have the error everywhere any time you have pasted it's a nightmare to maintain. If you repsect the "Open Close Principle" you'll rarely get edge effects, use unit test if you are afraid of that. For small jobs in PHP use at least something you get or write the HTML separately from the PHP code and reuse it any time you need it. Classes in PHP are mature, not as mature as other languages like python or java, but they are usable. There is tools to work with classes in PHP like Zend Studio that work very well. The use of classes or not depends not on the language you use but the programming paradigm you have choosen. I'm a OOP developer, I use PHP5, why do I have to shoot myself in the foot? When you find a simple bug in the code, and you can fix it simply, if you are not working on the code where you have found it, never fix it, even if it takes 5 seconds. He says to me his "best practices" are driven by the fact that he has a lot of experience in maintaining software in production (14 years) and he now knows what works and what doesn't work, what the community says is a fad, and the people advocating such principles as never copy & paste code, are not evolved in maintaining applications. What I think about that: If you find a bug fix it if you can do it quickly inform the people who've touched that code before, check if you have not introduced a new bug, ideally add a unit test for it. I currently work on a web commerce project, which serves 15k unique users per day. The code base has to be maintained and has been maintained this way since 2005. Ideally you include a short description of your position and experience in terms of years effectively maintaining an application which has been in production for real.

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• What are the disadvantages of self-encapsulation?

  - by Dave Jarvis

  Background Tony Hoare's billion dollar mistake was the invention of null. Subsequently, a lot of code has become riddled with null pointer exceptions (segfaults) when software developers try to use (dereference) uninitialized variables. In 1989, Wirfs-Brock and Wikerson wrote: Direct references to variables severely limit the ability of programmers to re?ne existing classes. The programming conventions described here structure the use of variables to promote reusable designs. We encourage users of all object-oriented languages to follow these conventions. Additionally, we strongly urge designers of object-oriented languages to consider the effects of unrestricted variable references on reusability. Problem A lot of software, especially in Java, but likely in C# and C++, often uses the following pattern: public class SomeClass { private String someAttribute; public SomeClass() { this.someAttribute = "Some Value"; } public void someMethod() { if( this.someAttribute.equals( "Some Value" ) ) { // do something... } } public void setAttribute( String s ) { this.someAttribute = s; } public String getAttribute() { return this.someAttribute; } } Sometimes a band-aid solution is used by checking for null throughout the code base: public void someMethod() { assert this.someAttribute != null; if( this.someAttribute.equals( "Some Value" ) ) { // do something... } } public void anotherMethod() { assert this.someAttribute != null; if( this.someAttribute.equals( "Some Default Value" ) ) { // do something... } } The band-aid does not always avoid the null pointer problem: a race condition exists. The race condition is mitigated using: public void anotherMethod() { String someAttribute = this.someAttribute; assert someAttribute != null; if( someAttribute.equals( "Some Default Value" ) ) { // do something... } } Yet that requires two statements (assignment to local copy and check for null) every time a class-scoped variable is used to ensure it is valid. Self-Encapsulation Ken Auer's Reusability Through Self-Encapsulation (Pattern Languages of Program Design, Addison Wesley, New York, pp. 505-516, 1994) advocated self-encapsulation combined with lazy initialization. The result, in Java, would resemble: public class SomeClass { private String someAttribute; public SomeClass() { setAttribute( "Some Value" ); } public void someMethod() { if( getAttribute().equals( "Some Value" ) ) { // do something... } } public void setAttribute( String s ) { this.someAttribute = s; } public String getAttribute() { String someAttribute = this.someAttribute; if( someAttribute == null ) { setAttribute( createDefaultValue() ); } return someAttribute; } protected String createDefaultValue() { return "Some Default Value"; } } All duplicate checks for null are superfluous: getAttribute() ensures the value is never null at a single location within the containing class. Efficiency arguments should be fairly moot -- modern compilers and virtual machines can inline the code when possible. As long as variables are never referenced directly, this also allows for proper application of the Open-Closed Principle. Question What are the disadvantages of self-encapsulation, if any? (Ideally, I would like to see references to studies that contrast the robustness of similarly complex systems that use and don't use self-encapsulation, as this strikes me as a fairly straightforward testable hypothesis.)

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• Oracle MAA Part 1: When One Size Does Not Fit All

  - by JoeMeeks

  The good news is that Oracle Maximum Availability Architecture (MAA) best practices combined with Oracle Database 12c (see video) introduce first-in-the-industry database capabilities that truly make unplanned outages and planned maintenance transparent to users. The trouble with such good news is that Oracle’s enthusiasm in evangelizing its latest innovations may leave some to wonder if we’ve lost sight of the fact that not all database applications are created equal. Afterall, many databases don’t have the business requirements for high availability and data protection that require all of Oracle’s ‘stuff’. For many real world applications, a controlled amount of downtime and/or data loss is OK if it saves money and effort. Well, not to worry. Oracle knows that enterprises need solutions that address the full continuum of requirements for data protection and availability. Oracle MAA accomplishes this by defining four HA service level tiers: BRONZE, SILVER, GOLD and PLATINUM. The figure below shows the progression in service levels provided by each tier. Each tier uses a different MAA reference architecture to deploy the optimal set of Oracle HA capabilities that reliably achieve a given service level (SLA) at the lowest cost.  Each tier includes all of the capabilities of the previous tier and builds upon the architecture to handle an expanded fault domain. Bronze is appropriate for databases where simple restart or restore from backup is ‘HA enough’. Bronze is based upon a single instance Oracle Database with MAA best practices that use the many capabilities for data protection and HA included with every Oracle Enterprise Edition license. Oracle-optimized backups using Oracle Recovery Manager (RMAN) provide data protection and are used to restore availability should an outage prevent the database from being able to restart. Silver provides an additional level of HA for databases that require minimal or zero downtime in the event of database instance or server failure as well as many types of planned maintenance. Silver adds clustering technology - either Oracle RAC or RAC One Node. RMAN provides database-optimized backups to protect data and restore availability should an outage prevent the cluster from being able to restart. Gold raises the game substantially for business critical applications that can’t accept vulnerability to single points-of-failure. Gold adds database-aware replication technologies, Active Data Guard and Oracle GoldenGate, which synchronize one or more replicas of the production database to provide real time data protection and availability. Database-aware replication greatly increases HA and data protection beyond what is possible with storage replication technologies. It also reduces cost while improving return on investment by actively utilizing all replicas at all times. Platinum introduces all of the sexy new Oracle Database 12c capabilities that Oracle staff will gush over with great enthusiasm. These capabilities include Application Continuity for reliable replay of in-flight transactions that masks outages from users; Active Data Guard Far Sync for zero data loss protection at any distance; new Oracle GoldenGate enhancements for zero downtime upgrades and migrations; and Global Data Services for automated service management and workload balancing in replicated database environments. Each of these technologies requires additional effort to implement. But they deliver substantial value for your most critical applications where downtime and data loss are not an option. The MAA reference architectures are inherently designed to address conflicting realities. On one hand, not every application has the same objectives for availability and data protection – the Not One Size Fits All title of this blog post. On the other hand, standard infrastructure is an operational requirement and a business necessity in order to reduce complexity and cost. MAA reference architectures address both realities by providing a standard infrastructure optimized for Oracle Database that enables you to dial-in the level of HA appropriate for different service level requirements. This makes it simple to move a database from one HA tier to the next should business requirements change, or from one hardware platform to another – whether it’s your favorite non-Oracle vendor or an Oracle Engineered System. Please stay tuned for additional blog posts in this series that dive into the details of each MAA reference architecture. Meanwhile, more information on Oracle HA solutions and the Maximum Availability Architecture can be found at: Oracle Maximum Availability Architecture - Webcast Maximize Availability with Oracle Database 12c - Technical White Paper

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• How to solve conflicts with another programmer..

  - by Tio

  Hi all.. I've read this question, but I think it doesn't really applies in my case.. I started to work at new company about 2 months ago with the position of senior web developer, there was already one programmer there, my position is above his, but I'm not his boss.. I don't tell him what to do.. Since the day I started to work at the company, I managed to implement a kind of a test server which he refuses to use, implemented a project management tool which he refuses to use also, and I'm in the process of implementing version control using mercurial ( damn Mercurial that's giving me so much headaches ), which he is going to use.. He is a nice guy, but just the other day we had a big discussion about "best practices", and "coding standards".. for me it's absolutely necessary to have this two things, at the place I'm currently working... otherwise it's not going to work.. This discussion, basically revolved about using short tags and the echo shortcut, and how we shouldn't use it anymore ( because I sometimes use short tags ).. this went for about 15 minutes, until I finally dropped the subject because I had work to do.. and of course he didn't budge even a millimeter, he's continuing to use short tags, and the echo shortcut and he not even cares about what I think.. When I mentioned that we are a team, he told me: "We are not a team, you work on your projects and I work on mine".. Let's just say, that the switch in my brain flipped, I raised my voice, and I told him that he was going nuts.. this was the most improper way to deal it with, I know, but there are certain things that can't be said to me.. The question here, is how do I deal with this? I want, to implement more changes on our work workflow, and I know that it's going to be a pain, with him always complaining and saying things like this.. Our boss is going to intervene in a few days, I talked to him today, the other programmer send him an email the day we had the discussion complaining.. Just to clarify, when I talk about implementing changes, I just don't appear at work, the next day with a sheet of paper, and say: "This is our we are doing things from now on! And there is no discussion.." For example, when I was trying to implement the project management tool, I took the time to talk to everybody that was going to be involved in it, to see what they think about it.. everyone was positive except him, he responded that it was just a mean to control us even more.. Does anyone has any idea on how to deal with this? PS: Truth to be told, I didn't start the best way with him, in the 4º day of work at the company, I found a really bad piece of code on our custom CMS, one of those things that I only expect to find in code produced by a programmer that has only 1 month of training in programming, and I talked to my boss about it... he showed up at the time I saw that piece of code, he saw my face and asked about it, so I told him.. I know the worst thing that can be said to a programmer is saying that their code is awful, but I've already learned that my code isn't the best of the world, so I take criticism in a completely different way now.. maybe he doesn't..

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• The Best Data Integration for Exadata Comes from Oracle

  - by maria costanzo

  Oracle Data Integrator and Oracle GoldenGate offer unique and optimized data integration solutions for Oracle Exadata. For example, customers that choose to feed their data warehouse or reporting database with near real-time throughout the day, can do so without decreasing  performance or availability of source and target systems. And if you ask why real-time, the short answer is: in today’s fast-paced, always-on world, business decisions need to use more relevant, timely data to be able to act fast and seize opportunities. A longer response to "why real-time" question can be found in a related blog post. If we look at the solution architecture, as shown on the diagram below,  Oracle Data Integrator and Oracle GoldenGate are both uniquely designed to take full advantage of the power of the database and to eliminate unnecessary middle-tier components. Oracle Data Integrator (ODI) is the best bulk data loading solution for Exadata. ODI is the only ETL platform that can leverage the full power of Exadata, integrate directly on the Exadata machine without any additional hardware, and by far provides the simplest setup and fastest overall performance on an Exadata system. We regularly see customers achieving a 5-10 times boost when they move their ETL to ODI on Exadata. For  some companies the performance gain is even much higher. For example a large insurance company did a proof of concept comparing ODI vs a traditional ETL tool (one of the market leaders) on Exadata. The same process that was taking 5hrs and 11 minutes to complete using the competing ETL product took 7 minutes and 20 seconds with ODI. Oracle Data Integrator was 42 times faster than the conventional ETL when running on Exadata.This shows that Oracle's own data integration offering helps you to gain the most out of your Exadata investment with a truly optimized solution. GoldenGate is the best solution for streaming data from heterogeneous sources into Exadata in real time. Oracle GoldenGate can also be used together with Data Integrator for hybrid use cases that also demand non-invasive capture, high-speed real time replication. Oracle GoldenGate enables real-time data feeds from heterogeneous sources non-invasively, and delivers to the staging area on the target Exadata system. ODI runs directly on Exadata to use the database engine power to perform in-database transformations. Enterprise Data Quality is integrated with Oracle Data integrator and enables ODI to load trusted data into the data warehouse tables. Only Oracle can offer all these technical benefits wrapped into a single intelligence data warehouse solution that runs on Exadata. Compared to traditional ETL with add-on CDC this solution offers: §  Non-invasive data capture from heterogeneous sources and avoids any performance impact on source §  No mid-tier; set based transformations use database power §  Mini-batches throughout the day –or- bulk processing nightly which means maximum availability for the DW §  Integrated solution with Enterprise Data Quality enables leveraging trusted data in the data warehouse In addition to Starwood Hotels and Resorts, Morrison Supermarkets, United Kingdom’s fourth-largest food retailer, has seen the power of this solution for their new BI platform and shared their story with us. Morrisons needed to analyze data across a large number of manufacturing, warehousing, retail, and financial applications with the goal to achieve single view into operations for improved customer service. The retailer deployed Oracle GoldenGate and Oracle Data Integrator to bring new data into Oracle Exadata in near real-time and replicate the data into reporting structures within the data warehouse—extending visibility into operations. Using Oracle's data integration offering for Exadata, Morrisons produced financial reports in seconds, rather than minutes, and improved staff productivity and agility. You can read more about Morrison’s success story here and hear from Starwood here. From an Irem Radzik article.

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