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• Case Study: Polystar Improves Telecom Networks Performance with Embedded MySQL

  - by Bertrand Matthelié

  Polystar delivers and supports systems that increase the quality, revenue and customer satisfaction of telecommunication services. Headquarted in Sweden, Polystar helps operators worldwide including Telia, Tele2, Telekom Malysia and T-Mobile to monitor their network performance and improve service levels. Challenges Deliver complete turnkey solutions to customers integrating a database ensuring high performance at scale, while being very easy to use, manage and optimize. Enable the implementation of distributed architectures including one database per server while maintaining a low Total Cost of Ownership (TCO). Avoid growing database complexity as the volume of mobile data to monitor and analyze drastically increases. Solution Evaluation of several databases and selection of MySQL based on its high performance, manageability, and low TCO. The MySQL databases implemented within the Polystar solutions handle on average 3,000 to 5,000 transactions per second. Up to 50 million records are inserted every day in each database. Typical installations include between 50 and 100 MySQL databases, up to 300 for the largest ones. Data is then periodically aggregated, with the original records being overwritten, as the need for detailed information becomes unnecessary to operators after a few weeks. The exponential growth in mobile data traffic driven by the proliferation of smartphones and usage of social media requires ever more powerful solutions to monitor, analyze and turn network data into actionable business intelligence. With MySQL, Polystar can deliver powerful, yet easy to manage, solutions to its customers. MySQL-based Polystar solutions enable operators to monitor, manage and improve the service levels of their telecom networks in over a dozen countries from a single location. The new and innovative MySQL features constantly delivered by Oracle help ensure Polystar that it will be able to meet its customer’s needs as they evolve. “MySQL has been a great embedded database choice for us. It delivers the high performance we need while remaining very easy to use, manage and tune. Power and simplicity at its best.” Mats Söderlindh, COO at Polystar.

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• Truecrypt or default Disk Utility on Mac?

  - by Kaushik Gopal

  Windows by default doesn't come with a password protect folder option (other that Win7 ultimate), so I used to swear by Truecrypt which was great. But I've read in a couple of places that Mac OS X by default has a way of protecting folders using the Default Disk Utility. So my question is which is better, using TrueCrypt on the Mac or just sticking with the default Disk Utils app? Can somebody let me know the advantages of one over the other? A summary from the very helpful answers below: if you're looking for cross-platform usage Truecrypt is the obvious tool of choice if you're looking for convenience, and intend to stick only to the Mac platform, use the default Disk Utils app.

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• High level vs. low level programming. Do I really have to choose?

  - by EpsilonVector

  Every once in a while I'm asked in interviews which I like the best- low level or high level. It seems to me that the implicit message is that they are both a specialty and they want to know which direction I'm heading. The trouble is, I seem to like both. Low level is extremely challenging and often requires a great deal of esoteric knowledge. High level is where all the sexy things happen: applications that people use directly, results that can be easily demonstrated (showed off) in a way that is accessible to everybody, and you get to work with really advanced tools and interact with new technologies. I would really love to do both, even if it means alternating between them (I doubt there are jobs that will let me do both simultaneously), but I'm guessing that the industry rewards specialists more than generalists. Will it really be problematic career wise if I never choose one over the other? Is it practical to alternate between the two in the sense that if I were to leave a job doing one of them, I should experience no "friction" trying to get a job doing the other (assuming I'm reasonably in the loop)? Are there career opportunities where you get to do both? Do I really have to choose one over the other?

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• Bluetooth not seeing mouse (Fedora)

  - by Chris

  I have a Lenovo S10 'netbook' that I've installed Fedora 17 ("LXDE spin") on. So far pretty much everything works great, except, the on-board Bluetooth. lsusb shows the controller present (0a5c:2101 Broadcom Corp. Bluetooth Controller), hcitool dev shows hci0 present, but when I put my mouse ("Lenovo Bluetooth Laser Mouse," which works perfectly paired with a MacBook Pro, MacBook Air, Mac mini, and Lenovo SL500 (with a USB dongle; running Windows 7)) into pairing mode and run hcitool scan (reports "Scanning ..." and, without further information or error message, returns to the shell prompt), blueman-manager, or bluetooth-wizard (from the gnome-bluetooth package) and try to detect the mouse, I get nothing... Frustrating! Thanks anyone who can point me in the right direction!

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• HTG Explains: Just How Bad Are Android Tablet Apps?

  - by Chris Hoffman

  Apple loves to criticize the state of Android tablet apps when pushing its own iPad tablets. But just how bad is the Android tablet app situation? Should you avoid Android tablets like the Nexus 7 because of the apps? It’s clear that Apple’s iPad is way ahead when it comes to the sheer quantity of tablet-optimized apps. It’s also clear that some popular apps — particularly touch-optimized games — only show up on iPad. But that’s not the whole story. The Basics First, let’s get an idea of the basic stuff that will work well for you on Android. An excellent web browser. Chrome has struggled with performance on Android, but hits its stride on the Nexus 7 (2013). Great, tablet-optimized apps for all of Google’s services, from YouTube to Gmail and Google Maps. Everything you need for reading, from Amazon’s Kindle app for eBooks, Flipboard and Feedly for new articles from websites, and other services like the popular Pocket read-it-later service. Apps for most popular media services, from Netflix, Hulu, and YouTube for videos to Pandora, Spotify, and Rdio for music. A few things aren’t available — you won’t find Apple’s iTunes and Amazon still doesn’t offer an Amazon Instant Video app for Android, while they do for iPad and even their own Android-based Kindle Fire devices. Android has very good app coverage when it comes to consuming content, whether you’re reading websites and ebooks or watching videos and listening to music. You can play almost any Android smartphone game, too. For content consumption, Android is better than something like Windows 8, which lacks apps for Google services like YouTube and still doesn’t have apps for popular media services like Spotify and Rdio. How Android Scales Smartphone Apps Let’s look at how Android scales smartphone apps. Now, bear with us here — we know “scaling” is a dirty word considering how poorly Apple’s iPad scales iPhone apps, but it’s not as bad on Android. When an iPad runs an iPhone app, it simply doubles the pixels and effectively zooms in. For example, if you had  Twitter app with five tweets visible at once on an iPhone and ran the same app on an iPad, the iPad would simply “zoom in” and enlarge the same screen — you’d still see five tweets, but each tweet would appear larger. This is why developers create optimized iPad apps with their own interfaces. It’s especially important on Apple’s iOS. Android devices come in all shapes and sizes, so Android apps have a smarter, more intelligent way to adapt to different screen sizes. Let’s say you have a Twitter app designed for smartphones and it only shows five tweets at once when run on a phone. If you ran the same app on a tablet, you wouldn’t see the same five tweets — you’d see ten or more tweets. Rather than simply zooming in, the app can show more content at the same time on a tablet, even if it was never optimized for tablet-size screens. While apps designed for smartphones aren’t generally ideal, they adapt much better on Android than they do on an iPad. This is particularly true when it comes to games. You’re capable of playing almost any Android smartphone game on an Android tablet, and games generally adapt very well to the larger screen. This gives you access to a huge catalog of games. It’s a great option to have, especially when you look at Microsoft’s Window 8 and consider how much better the touch-based app and game selection would be if Microsoft allowed its users to run Windows Phone games on Windows 8. 7-inch vs 10-inch Tablets The Twitter example above wasn’t just an example. The official Twitter app for Android still doesn’t have a tablet-optimized interface, so this is the sort of situation you’d have to deal with on an Android tablet. On the popular Nexus 7, Twitter is an example of a smartphone app that actually works fairly well — in portrait mode, you can see many more tweets on screen at the same time and none of the space really feels all that wasted. This is important to consider — smartphone apps like Twitter often scale quite well to 7-inch screens because a 7-inch screen is much closer in form factor to a smartphone than a 10-inch screen is. When you begin to look at 10-inch Android tablets that are the same size as an iPad, the situation changes. While the Twitter app works well enough on a Nexus 7, it looks horrible on a Nexus 10 or other 10-inch tablet. Running many smartphone-designed apps — possible with the exception of games — on a 10-inch tablet is a frustrating, poor experience. There’s much more white, empty space in the interface. It feels like you’re using a smartphone app on a large screen, and what’s the point of that? A tablet-optimized Twitter app for Android is finally on its way, but this same situation will repeat with many other types of apps. For example, Facebook doesn’t offer a tablet-optimized interface, but it’s okay on a Nexus 7 anyway. On a 10-inch screen, it probably wouldn’t be anywhere near as nice an experience. It goes without saying that Facebook and Twitter both offer iPad apps with interfaces designed for a tablet-size screen. Here’s another problematic app — the official Yelp app for Android. Even just using it on a 7-inch Nexus 7 will be a poor experience, while it would be much worse on a larger 10-inch tablet app. Now, it’s true that many — maybe even most — of the popular apps you might want to run today are optimized for Android tablets. But, when you look at the situation when it comes to popular apps like Twitter, Facebook, and Yelp, it’s clear Android is still behind in a meaningful way. Price Let’s be honest. The thing that really makes Android tablets compelling — and the only reason Android tablets started seeing real traction after years of almost complete dominance by Apple’s iPads — is that Android tablets are available for so much cheaper than iPads. Google’s latest Nexus 7 (2013) is available for only $230. Apple’s non-retina iPad Mini is available at $300, which is already $70 more. In spite of that, the iPad Mini has much older, slower internals and a much lower resolution screen. It’s not as nice to look at when it comes to reading or watching movies, and the iPad Mini reportedly struggles to run Apple’s latest iOS 7. In contrast, the new Nexus 7 has a very high resolution screen, speedy internals, and runs Android very well with little-to-no lag in real use. We haven’t had any problems with it, unlike all the problems we unfortunately encountered with the first Nexus 7. For a really comparable experience to the current Nexus 7, you’d want to get one of Apple’s new retina iPad Minis. That would cost you $400, another $170 over the Nexus 7. In fact, it’s possible to regularly find sales on the Nexus 7, so if you waited you could get it for just $200 — half the price of the iPad mini with a comparable screen and internals. (In fairness, the iPad certainly has better hardware — but you won’t feel if it you’re just using your tablet to browse the web, watch videos, and do other typical tablet things.) This makes a tablet like the popular Nexus 7 a very good option for budget-conscious users who just want a high-quality device they can use to browse the web, watch videos, play games, and generally do light computing. There’s a reason we’re focusing on the Nexus 7 here. The combination of price and size brings it to a very good place. It’s awfully cheap for the high-quality experience you get, and the 7-inch screen means that even the non-tablet-optimized apps you may stumble across will often work fairly well. On the other hand, more expensive 10-inch Android tablets are still a tougher sell. For $400-$500, you’re getting awfully close to Apple’s full-size iPad price range and Android tablets don’t have as good an app ecosystem as an iPad. It’s hard to recommend an expensive, 10-inch Android tablet over a full-size iPad to average users. In summary, the Android app tablet app situation is nowhere near as bad as it was a few years ago. The success of the Nexus 7 proves that Android tablets can be compelling experiences, and there are a wide variety of strong apps. That said, more expensive 10-inch Android tablets that compete directly with the full-size iPad on price still don’t make much sense for most people.  Unless you have a specific reason for preferring an Android tablet, it’s tough not to recommend an iPad if you’re looking at spending $400+ on a 10-inch tablet. Image Credit: Christian Ghanime on Flickr, Christian Ghanime on Flickr     

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• FoxTales: Behind the Scenes at Fox Software by Kerry Nietz

  Flash backs from the past! It's truly amazing to discover that software development from freshman to senior level as well as project management hasn't changed that much. Kerry Nietz describes his memoir from his final year at college to his first job at Fox Software to 'an early retirement' at Microsoft. This title also brought his other fictional novels to my attention. Once again here is the review I published on Amazon: Built to last! I have been around in software development for more than a decade now but honestly I have to admit it is only now that I took the opportunity to read about the history of my used to be primary programming language. In fact, I started with Visual FoxPro 6 back in 1999 and went only down to FoxPro for Windows 2.6 during migration projects - long after the stories described in this title. It is really interesting to see how they actually managed to create a great product with such a small team of developers. "Create the best Report Writer in the world, out of only sawdust, bubblegum, and dreams." - That's the best sentence I'm going to quote from this title in the future. An inspiration to achieve the impossible, only by taking small steps. Just begin the journey - one step after the next one. If you fall, stand up and continue to walk. Kerry takes the reader on an amazing trip through almost 4 years working at a small software company in Perrysburg, Ohio. That went from a another 'look-alike' of the mighty Ashton-Tate dBase to the leading force in database development, long before Microsoft Access (project name: Cirrus) was even finished. It survived Borland Paradox and even nowadays Visual FoxPro is still in daily use in thousands of companies world-wide. Actually, I'm glad that I had the chance to foster my programming knowledge with Visual FoxPro. After his excellent work in software development, Kerry went for a second career as a writer. I'm looking forward to read his other titles soon:

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• Optimizing PHP<>MySQL performance

  - by BarsMonster

  I am trying to optimize my PHP<MySQL on this test script: <? for($i=0;$i<100;$i++)//Itterations count $res.= var_dump(loadRow("select body_ru from articles where id>$i*50 limit 100")); print_r($res); ?> I have APC, and article table have an index on id. Also, all these queries are hitting query cache, so sole MySQL performance if great. But when I am using ab -c 10 -t 10 to bench this scipt, I am getting: 100 itterations: ~100req/sec (~10'000 MySQL queries per second) 5 itteration: ~200req/sec 1 itteration: ~380req/sec 0 itteration: ~580req/sec I've tried to disable persistent connections in PHP - it made it slower a bit. So, how can I make it work faster, provided that MySQL is not limiting performance here?

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• Windows 8 + Ubuntu dualboot problem - ubuntu does not load after windows updates

  - by Michal Biros

  I have installed Windows 8 64-bit and Ubuntu 14.04 64-bit in dualboot with EFI mode. Everything worked great. I could run Ubuntu or Windows without any problems. Only one little issue was that Windows locked NTFS partitions when I shut it down. When I clicked on restart button in Windows and started Ubuntu, partitions mounted successfully. But today ... I opened windows and downloaded all available updates. When I wanted to come back to Ubuntu I noticed that grub did not count down seconds to automatic start. After choosing Ubuntu option manually, the OS did not load. Just black screen with white underscore in the upper left corner. Windows is accessible always without such issues. Last time I solved it by reinstalling ubuntu but I dont want to do it each time windows downloads some updates. Have you ever meet such problem, or do you know how to solve it? EDIT Ubuntu boots, but it won't start. It ends on loading screen.

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• Sharepoint 2010 site access denied for Active Dirtectory group member

  - by Mia

  I created a blank site in Sharepoint 2010 and in Site Actions-->Permissions I removed all the users and added an Active directory group which has me as member and few others. After this I logged in as myself and it does not show that Portal on Left navigation. If I try to browse to that portal as myself it says "access denied"? I don't know where I am wrong. I am stuck from yesterday. If some one could help it would be great. Thanks.

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• Focus On SOA & BPM for Oracle OpenWorld Now Available

  - by Lionel Dubreuil

  To help our valued customers & partners make the most of time spent at Oracle Openworld, please check out the Focus On Oracle Fusion Middleware documents.  Over the years, we've learned that these provide a great roadmap to must-attend sessions, demos, partner exhibits, and networking events during Oracle OpenWorld. SOA and BPM SOA for Developers BPM In addition to those “Focus On..” documents, session details (speakers, abstracts) can be found in the Content Catalog at: https://oracleus.activeevents.com/connect/search.ww?event=openworld We strongly recommend our customers to attend the following sessions: Service Integration (SOA) & BPM: “Using the Right Tools, Techniques, and Technologies for Integration Projects”  Monday, 10/1/2012; 3:15 PM; Moscone South - 308 BPM Suite: “Oracle Unified Business Process Management Suite 11g Overview and Roadmap” Monday, 10/1/ 2012; 12:15 PM; Moscone South – 308 SOA Suite:“Oracle SOA Suite, the Most Capable Tool for Every Possible Integration Challenge” Monday, 10/1/2012; 10:45 AM; Moscone South - 102 Foundation Pack: “Jump-starting Integration Projects with Oracle AIA Foundation Pack” Tuesday, 10/2/2012; 1:15 PM; Marriott Marquis - Salon 7 Oracle Enterprise Repository: “Gaining Victory over SOA and Application Integration Complexity” Tuesday, 10/2/2012; 1:15 PM; Moscone South - 310 See you in San Francisco! Not attending the show?  Some of the general and key sessions will be available online - so please stay tuned for those announcements as Oracle OpenWorld gets closer.

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• Focus On SOA & BPM for Oracle OpenWorld Now Available

  - by Lionel Dubreuil

  To help our valued customers & partners make the most of time spent at Oracle Openworld, please check out the Focus On Oracle Fusion Middleware documents.  Over the years, we've learned that these provide a great roadmap to must-attend sessions, demos, partner exhibits, and networking events during Oracle OpenWorld. SOA and BPM SOA for Developers BPM In addition to those “Focus On..” documents, session details (speakers, abstracts) can be found in the Content Catalog at: https://oracleus.activeevents.com/connect/search.ww?event=openworld We strongly recommend our customers to attend the following sessions: Service Integration (SOA) & BPM: “Using the Right Tools, Techniques, and Technologies for Integration Projects”  Monday, 10/1/2012; 3:15 PM; Moscone South - 308 BPM Suite: “Oracle Unified Business Process Management Suite 11g Overview and Roadmap” Monday, 10/1/ 2012; 12:15 PM; Moscone South – 308 SOA Suite:“Oracle SOA Suite, the Most Capable Tool for Every Possible Integration Challenge” Monday, 10/1/2012; 10:45 AM; Moscone South - 102 Foundation Pack: “Jump-starting Integration Projects with Oracle AIA Foundation Pack” Tuesday, 10/2/2012; 1:15 PM; Marriott Marquis - Salon 7 Oracle Enterprise Repository: “Gaining Victory over SOA and Application Integration Complexity” Tuesday, 10/2/2012; 1:15 PM; Moscone South - 310 See you in San Francisco! Not attending the show?  Some of the general and key sessions will be available online - so please stay tuned for those announcements as Oracle OpenWorld gets closer.

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• Focus On SOA & BPM for Oracle OpenWorld Now Available

  - by Lionel Dubreuil

  To help our valued customers & partners make the most of time spent at Oracle Openworld, please check out the Focus On Oracle Fusion Middleware documents.  Over the years, we've learned that these provide a great roadmap to must-attend sessions, demos, partner exhibits, and networking events during Oracle OpenWorld. SOA and BPM SOA for Developers BPM In addition to those “Focus On..” documents, session details (speakers, abstracts) can be found in the Content Catalog at: https://oracleus.activeevents.com/connect/search.ww?event=openworld We strongly recommend our customers to attend the following sessions: Service Integration (SOA) & BPM: “Using the Right Tools, Techniques, and Technologies for Integration Projects”  Monday, 10/1/2012; 3:15 PM; Moscone South - 308 BPM Suite: “Oracle Unified Business Process Management Suite 11g Overview and Roadmap” Monday, 10/1/ 2012; 12:15 PM; Moscone South – 308 SOA Suite:“Oracle SOA Suite, the Most Capable Tool for Every Possible Integration Challenge” Monday, 10/1/2012; 10:45 AM; Moscone South - 102 Foundation Pack: “Jump-starting Integration Projects with Oracle AIA Foundation Pack” Tuesday, 10/2/2012; 1:15 PM; Marriott Marquis - Salon 7 Oracle Enterprise Repository: “Gaining Victory over SOA and Application Integration Complexity” Tuesday, 10/2/2012; 1:15 PM; Moscone South - 310 See you in San Francisco! Not attending the show?  Some of the general and key sessions will be available online - so please stay tuned for those announcements as Oracle OpenWorld gets closer.

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• Focus On SOA & BPM for Oracle OpenWorld Now Available

  - by Lionel Dubreuil

  To help our valued customers & partners make the most of time spent at Oracle Openworld, please check out the Focus On Oracle Fusion Middleware documents.  Over the years, we've learned that these provide a great roadmap to must-attend sessions, demos, partner exhibits, and networking events during Oracle OpenWorld. SOA and BPM SOA for Developers BPM In addition to those “Focus On..” documents, session details (speakers, abstracts) can be found in the Content Catalog at: https://oracleus.activeevents.com/connect/search.ww?event=openworld We strongly recommend our customers to attend the following sessions: Service Integration (SOA) & BPM: “Using the Right Tools, Techniques, and Technologies for Integration Projects”  Monday, 10/1/2012; 3:15 PM; Moscone South - 308 BPM Suite: “Oracle Unified Business Process Management Suite 11g Overview and Roadmap” Monday, 10/1/ 2012; 12:15 PM; Moscone South – 308 SOA Suite:“Oracle SOA Suite, the Most Capable Tool for Every Possible Integration Challenge” Monday, 10/1/2012; 10:45 AM; Moscone South - 102 Foundation Pack: “Jump-starting Integration Projects with Oracle AIA Foundation Pack” Tuesday, 10/2/2012; 1:15 PM; Marriott Marquis - Salon 7 Oracle Enterprise Repository: “Gaining Victory over SOA and Application Integration Complexity” Tuesday, 10/2/2012; 1:15 PM; Moscone South - 310 See you in San Francisco! Not attending the show?  Some of the general and key sessions will be available online - so please stay tuned for those announcements as Oracle OpenWorld gets closer.

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• ODI 12c - Getting up and running fast

  - by David Allan

  Here's a quick A-B-C to show you how to quickly get up and running with ODI 12c, from getting the software to creating a repository via wizard or the command line, then installing an agent for running load plans and the like. A. Get the software from OTN and install studio. Check out this viewlet here for quickly doing this. B. Create a repository using the RCU, check out this viewlet here which uses the FMW Repository Creation Utility.  You can also silently create (and drop) a repository using the command line, this is really easy. .\rcu -silent -createRepository -connectString yourhost:1521:orcl.st-users.us.oracle.com -dbUser sys -dbRole sysdba -useSamePasswordForAllSchemaUsers true -schemaPrefix X -component ODI -component IAU  -component IAU_APPEND  -component IAU_VIEWER -component OPSS < passwords.txt where the passwords file contains info such as; sysdba_passwd newschema_passwd odi_user_passwd D workreposname workrepos_passwd  You can find details about the silent use of RCU here in the FMW documentation. C. Quickly create an agent for executing load plans and the like -  there is a great OBE for this, check it out here. If you are on your laptop and just wanting as minimal an agent as possible then this link is a must. With these three steps you are ready to get to the fun stuff! Check out more OBEs here - keep on the lookout for more!

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• Exploring MDS Explorer by Mark Nelson

  - by JuergenKress

  Recently, I posted about my colleague Olivier’s MDS Explorer tool, which is a great way to get a look inside your MDS repository. I have been playing around with it a little bit, nothing much really, just some cosmetic stuff, but you might like to take a look at it. I made it format the documents nicely with proper indentation, and with line numbers and a nicer editor. It also will warn you if you are about to open a large document so that you know it has not crashed, but that you just have to be patient. And I added some icons and stuff. There is even a nice Dora the Explorer picture hiding in there for those who care to look for it . Read the full article here. SOA & BPM Partner Community For regular information on Oracle SOA Suite become a member in the SOA & BPM Partner Community for registration please visit  www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Mix Forum Technorati Tags: MDS Explorerer,IDM,SOA Community,Oracle SOA,Oracle BPM,BPM,Community,OPN,Jürgen Kress,Mark Nelson

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• SQLAuthority News – SQL Server Interview Questions And Answers Book Summary

  - by pinaldave

  Today we are using computers for various activities, motor vehicles for traveling to places, and mobile phones for conversation. How many of us can claim the invention of micro-processor, a basic wheel, or the telegraph? Similarly, this book was not written overnight. The journey of this book goes many years back with many individuals to be thanked for. To begin with, we want to thank all those interviewers who reject interviewees by saying they need to know ‘the key things’ regardless of having high grades in class. The whole concept of interview questions and answers revolves around knowing those ‘key things’. The core concept of this book will continue to evolve over time. I am sure many of you will come along with us on this journey and submit your suggestions to us to make this book a key reference for anybody who wants to start with SQL Server. Today we want to acknowledge the fact that you will help us keep this book alive forever with the latest updates. We want to thank everyone who participates in this journey with us. Though each of these chapters are geared towards convenience we highly recommend reading each of the sections irrespective of the roles you might be doing since each of the sections have some interesting trivia about working with SQL Server. In the industry the role of accidental DBA’s (especially with SQL Server) is very common. Hence if you have performed the role of DBA for a short stint and want to brush-up your fundamentals then the upcoming sections will be a great review. Table Of Contents Database Concepts With Sql Server Common Generic Questions & Answers Common Developer Questions Common Tricky Questions Miscellaneous Questions On Sql Server 2008 Dba Skills Related Questions Data Warehousing Interview Questions & Answers General Best Practices [Amazon] | [Flipkart] Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Best Practices, Database, Pinal Dave, PostADay, SQL, SQL Authority, SQL Interview Questions and Answers, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority News, T SQL, Technology

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• How to improve performance of map that loads new overlay images

  - by anthonysomerset

  I have inherited a website to maintain that uses a html map overlaying a real map to link specific countries to specific pages. previously it loaded the default map image, then with some javascript it would change the image src to an image with that particular country in a different colour on mouseover and reset the image source back to the original image on mouse out to make maintenance (adding new countries) easier i made the initial map a background image by utilising some CSS for the div tag, and then created new images for each country which only had that countries hightlight so that the images remain fairly small. this works great but theres one issue which is particularly noticeable on slower internet connections when you hover over a country if you dont have the image file in your browser cache or downloaded it wont load the image unless you hover over another country and then back onto the first country - i guess this is due to the image having to manually be downloaded on first hover. My question: is it possible to force the load of these extra images AFTER the page and all the other assets have finished loading so that this behaviour is all but eliminated? the html code for the MAP is as follows: <div class="gtmap"><img id="Image-Maps_6200909211657061" src="<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png" usemap="#Image-Maps_6200909211657061" alt="We offer Guided Motorcycle Tours all around the world" width="615" height="296" /> <map id="_Image-Maps_6200909211657061" name="Image-Maps_6200909211657061"> <area shape="poly" coords="511,134,532,107,542,113,520,141" href="/guided-motorcycle-tours-japan/" alt="Guided Japan Motorcycle Tours" title="Japan" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-japan.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="252,61,266,58,275,64,262,68" href="/guided-motorcycle-tour.php?iceland-motorcycle-adventure-39" alt="Guided Iceland Motorcycle Tours" title="Iceland" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-iceland.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="587,246,597,256,577,279,568,270" href="/guided-motorcycle-tour.php?new-zealand-south-island-adventure-10" alt="New Zealand Guided Motorcycle Tours" title="New Zealand" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-nz.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="418,133,412,145,412,154,421,178,430,180,430,166,443,154,443,145,438,144,433,142,430,138,431,130,430,129,425,128" href="/guided-motorcycle-tours-india/" alt="India Guided Motorcycle Tours" title="India" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-india.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="460,152,466,149,474,165,470,171,466,161" href="/guided-motorcycle-tours-laos/" alt="Laos Guided Motorcycle Tours" title="Laos" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-laos.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="468,179,475,166,468,152,475,152,482,169" href="/guided-motorcycle-tour.php?indochina-motorcycle-adventure-tour-32" onClick="javascript: pageTracker._trackPageview('/internal-links/guided-tours/map/vietnam');" alt="Vietnam Guided Motorcycle Tours" title="Vietnam" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-viet.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="330,239,337,235,347,226,352,233,351,243,344,250,335,253,327,255,323,249,322,242,323,241" href="/guided-motorcycle-tours-southafrica/" alt="South Africa Guided Motorcycle Tours" title="South Africa" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-sa.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="290,77,293,86,298,96,286,102,285,97,285,89,282,84,282,79" href="/guided-motorcycle-tour.php?great-britain-isle-of-man-scotland-wales-uk-18" alt="United Kingdom" title="United Kingdom Guided Motorcycle Tours" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-uk.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="357,118,368,118,369,126,345,129,338,125,338,117,342,115,348,116" href="/guided-motorcycle-tour.php?explore-turkey-adventure-45" alt="Turkey" title="Turkey Guided Motorcycle Tours" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-turkey.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="206,95,193,101,185,101,178,106,165,111,157,109,147,105,134,103,121,103,107,103,96,103,86,104,81,99,77,91,70,83,62,79,60,72,61,64,59,57,60,51,71,50,83,49,95,50,107,54,117,53,129,47,137,36,148,37,163,38,177,44,187,54,195,60,184,72,191,80,200,87" href="/guided-motorcycle-tours-canada/" alt="Guided Canada Motorcycle Tours" title="Canada" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-canada.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="61,75,60,62,60,55,59,44,51,44,43,43,36,42,28,43,23,48,17,51,15,62,19,74,27,79,19,83,16,93,35,83,43,77,50,75,55,75" href="/guided-motorcycle-tours-alaska/" alt="Guided Alaska Motorcycle Tours" title="Alaska" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-alaska.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="82,101,99,101,133,101,148,105,161,110,172,106,187,100,180,113,171,122,165,131,159,149,147,141,137,140,129,147,120,141,112,138,103,137,93,132,86,122,86,112,86,106" href="/guided-motorcycle-tours-usa/" alt="USA Guided Motorcycle Tours" title="USA" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-usa.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="178,225,180,214,175,208,174,204,178,198,174,193,167,192,157,199,158,204,164,211,167,218" href="/guided-motorcycle-tour.php?peru-machu-picchu-adventure-25" alt="Peru Guided Motorcycle Tours" title="Peru" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-peru.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="172,226,169,239,166,256,166,267,164,279,171,277,174,262,175,250,179,234,180,225,176,224" href="/guided-motorcycle-tours-chile/" alt="Guided Chile Motorcycle Tours" title="Chile" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-chile.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> <area shape="poly" coords="199,260,194,261,187,265,184,276,183,296,170,292,168,282,174,270,174,257,177,245,180,230,190,228,205,237,199,245" href="/guided-motorcycle-tours-argentina/" alt="Guided Argentina Motorcycle Tours" title="Argentina" onmouseover="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-arg.png';" onmouseout="if(document.images) document.getElementById('Image-Maps_6200909211657061').src='<?php echo cdnhttpsCheck(); ?>assets/wmap/a-guided-tours-map-blank.png';" /> </map> </div> The <?php echo cdnhttpsCheck(); ?> is just a site specific function that gets the correct web domain/url from a config file to load resources from CDN where possible (eg all non HTTPS requests) We are loading Jquery at the bottom of the HTML if anybody wonders why it is missing from the code snippet for reference, the page with the map in question is found here: http://www.motoquest.com/guided-motorcycle-tours/

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• iPhone/iPad: Get Alerts When Paid Apps Go Free

  - by Gopinath

  iPhone users has thousands of cool applications to choose. These apps are either paid or absolutely free. Many of the paid applications goes free for either a limited time or forever depending on the mood of their developers. Will it not be cool to get alerts whenever a paid app goes free? Yeah, it will be great. Free App Alert is a handy website that checks iTunes store regularly and sends alerts to it’s subscribers about the apps that have gone from paid to free. You can receive the alerts by following them on twitter, facebook or subscribing to the traditional RSS feeds(yeah RSS is a traditional technology). The home page of this website shows the apps that have gone free today and you can browse through the previous day free apps listing with the help of links available at the bottom. Free App Alert is definitely a cool site to check out for iPhone/iPod/iPad users and certainly easier than scrolling through iTunes store and checking prices. Tip: Immediately download the app that have gone from paid to free as many apps are free for limited time. You can see many free apps going back to paid version if you go through the previous pages the website. Join us on Facebook to read all our stories right inside your Facebook news feed.

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• Is ASP.NET MVC too much overhead for smaller projects?

  - by Alexander Ryan Baggett

  I will be honest I don't really know much about MVC other than the stuff you can read online in 5 minutes. Unfortunately this doesn't really tell me whether its suited to smaller projects or not. I also read this related question and its chosen answer, but the business perspective is not a concern in this case for me as I am the only one making it. The next answer proceeds to say why it is more flexible. Sure, that's great. But my question is again, if its an ideal choice for a small project. For example I would rather use winforms to make a simple mockup of a small desktop program than do it on WPF because of the overhead of custom styling. So I have a project that will essentially have about 6-8 pages that read excel files and user input use that to pull a bit of data from databases and output resulting excel files. I will be the only one working on this project. If I used webforms I would expect it to take no more than 2-3 weeks. Now I am 100% comfortable with webforms. And I know its easy to do a small project in webforms. But I have only heard good things about MVC so I am seriously considering it.

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• Raid0 performance degradation?

  - by davy8

  Not sure if this belongs here or on SuperUser, feel free to move as appropriate. I've noticed the performance on my RAID0 setup seems to have degraded over the past months. The throughput is fine, but I think the random access time has increased or something. In use I generally see about 1-5mb/sec when loading stuff in Visual Studio and other apps and it doesn't seem like the CPU is bottlenecking as the CPU utilization is pretty low. I don't recall what Access Time used to be, but HD Tune is reporting 12.6ms Read throughput is showing as averaging about 125MB/sec so it should be great for sequential reads. Defrag daily and it shows fragmentation levels low, so that shouldn't be an issue. Additional info, Windows 7 x64, Intel raid controller on mobo, WD Black 500GB (I think 32mb cache) x2.

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• Raid0 performance degradation?

  - by davy8

  Not sure if this belongs here or on SuperUser, feel free to move as appropriate. I've noticed the performance on my RAID0 setup seems to have degraded over the past months. The throughput is fine, but I think the random access time has increased or something. In use I generally see about 1-5mb/sec when loading stuff in Visual Studio and other apps and it doesn't seem like the CPU is bottlenecking as the CPU utilization is pretty low. I don't recall what Access Time used to be, but HD Tune is reporting 12.6ms Read throughput is showing as averaging about 125MB/sec so it should be great for sequential reads. Defrag daily and it shows fragmentation levels low, so that shouldn't be an issue. Additional info, Windows 7 x64, Intel raid controller on mobo, WD Black 500GB (I think 32mb cache) x2.

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• Gmail: Find emails that do not have a label

  - by DGHelp

  Hello, I am trying to search for all of my mail that does not have a label. I label all of my mail then archive it but I think throughout the years I have forgotten some. Is there anyway I can search for all mail that does not have a label? Idea I had: Go to my All Mail and apply an arbitrary label to all of them, then go to each of my labels and remove my arbitrary one. However, is there a quick way to add a label to ALL mail for this idea to work? Also, I think this will apply it to even my sent mail instead of just mail that was sent to me? Any ideas/suggestions would be great. Thanks!

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• Online Media Daily: Oracle Takes Social Marketing Seriously

  - by Richard Lefebvre

  In the article published on Nov 12, 2012 and titled "Oracle Integrates Social Marketing Into Enterprise To Gain Marketing Revs," Online Media Daily explores Oracle's approach to social marketing. The publication says that Oracle is focused on showing marketers how to integrate social data into corporate business processes and how to "socialize" the corporate world. The article goes on to state:"Enterprise software companies like Oracle, SAP, IBM, Salesforce and Microsoft have been slowly building up an expertise in social marketing to integrate the data into traditional enterprise resource planning, and customer relationship management tools into social marketing tools.   Enterprise software companies like Oracle, SAP, IBM, Salesforce and Microsoft have been slowly building up an expertise in social marketing to integrate the data into traditional enterprise resource planning, and customer relationship management tools into social marketing tools.    Read more: http://www.mediapost.com/publications/article/187096/oracle-integrates-social-marketing-into-enterprise.html#ixzz2CPMZ1w3D Meg Bear, VP of cloud social platform at Oracle, sees the integration with ERP systems as a differentiator for the company. Oracle Social Relationship Management launched last month. It integrates social data into traditional enterprise applications like Oracle Fusion Marketing, Oracle Fusion Sales Catalog, Oracle ATG Web Commerce and Oracle ERP." The post goes on to quote a Forrester analyst stating the following:""There's room for any process-driven application to run more efficiently, especially if they're socially enabled," said Rob Koplowitz, VP and principal analyst at Forrester Research. "It takes the human part of the process not generally captured today to provide better access to content, information and collective actions." Koplowitz said several acquisitions support Oracle's long-term vision: to layer social on top of other enterprise apps, like its ERP platform." With many great acquisitions under our belt and organically grown social tools, the market recognizes that Oracle is poised to seize the moment in socially enabled business apps. Continue reading the full article here.

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• ArchBeat Link-o-Rama for November 21, 2012

  - by Bob Rhubart

  Fault Handling and Prevention - Part 1 | Guido Schmutz and Ronald van Luttikhuizen In this technical article, part one of a four part series, Oracle ACE Directors Guido Schmutz and Ronald van Luttikhuizen guide you through an introduction to fault handling in a service-oriented environment using Oracle SOA Suite and Oracle Service Bus. One Stop Shop for Oracle Webcasts Webcasts can be a great way to get information about Oracle products without having to go cross-eyed reading yet another document off your computer screen. Oracle's new Webcast Center offers selectable filtering to make it easy to get to the information you want. Yes, you have to register to gain access, but that process is quick, and with over 200 webcasts to choose from you know you'll find useful content. Oracle on Oracle: Is that all? (Identity Management)| Darin Pendergraft Darin Pendergraft shares a discussion with Jaime Cardoso aboutthe latter's experience with Oracle's IDM products. What's particularly interesting is that the discussion grew out of Jaime's highly critical comment that Darin missed important pointsabout those products in an earlier interview Chirag Andani. If that ain't social engagement, I don't know what is. I.T. Chargeback : Core to Cloud Computing | Zero to Cloud "While chargeback has existed as a concept for many years (especially in mainframe environments), it is the move to this self-service model that has created a need for a new breed of chargeback applications for cloud," says Mark McGill. "Enabling self-service without some form of chargeback is like opening a shop where all of the goods are free." New Self-paced Online Oracle BPM 11g Developer Training | Dan Atwood Oracle ACE Dan Atwood of Avio Consulting shares a lot of information about a new Oracle BPM 11g Developer Workshop. JPA SQL and Fetching tuning ( EclipseLink ) | Edwin Biemond Oracle ACE Edwin Biemond's post illustrates how to "use the department and employee entity of the HR Oracle demo schema to explain the JPA options you have to control the SQL statements and the JPA relation Fetching." Thought for the Day "Team development is like a birthday cake. Everybody gets a piece." — Assaad Chalhoub Source: SoftwareQuotes.com

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• Where'd My Data Go? (and/or...How Do I Get Rid of It?)

  - by David Paquette

  Want to get a better idea of how cascade deletes work in Entity Framework Code First scenarios? Want to see it in action? Stick with us as we quickly demystify what happens when you tell your data context to nuke a parent entity. This post is authored by Calgary .NET User Group Leader David Paquette with help from Microsoft MVP in Asp.Net James Chambers. We got to spend a great week back in March at Prairie Dev Con West, chalk full of sessions, presentations, workshops, conversations and, of course, questions.  One of the questions that came up during my session: "How does Entity Framework Code First deal with cascading deletes?". James and I had different thoughts on what the default was, if it was different from SQL server, if it was the same as EF proper and if there was a way to override whatever the default was.  So we built a set of examples and figured out that the answer is simple: it depends.  (Download Samples) Consider the example of a hockey league. You have several different entities in the league including games, teams that play the games and players that make up the teams. Each team also has a mascot.  If you delete a team, we need a couple of things to happen: The team, games and mascot will be deleted, and The players for that team will remain in the league (and therefore the database) but they should no longer be assigned to a team. So, let's make this start to come together with a look at the default behaviour in SQL when using an EDMX-driven project. The Reference – Understanding EF's Behaviour with an EDMX/DB First Approach First up let’s take a look at the DB first approach.  In the database, we defined 4 tables: Teams, Players, Mascots, and Games.  We also defined 4 foreign keys as follows: Players.Team_Id (NULL) –> Teams.Id Mascots.Id (NOT NULL) –> Teams.Id (ON DELETE CASCADE) Games.HomeTeam_Id (NOT NULL) –> Teams.Id Games.AwayTeam_Id (NOT NULL) –> Teams.Id Note that by specifying ON DELETE CASCADE for the Mascots –> Teams foreign key, the database will automatically delete the team’s mascot when the team is deleted.  While we want the same behaviour for the Games –> Teams foreign keys, it is not possible to accomplish this using ON DELETE CASCADE in SQL Server.  Specifying a ON DELETE CASCADE on these foreign keys would cause a circular reference error: The series of cascading referential actions triggered by a single DELETE or UPDATE must form a tree that contains no circular references. No table can appear more than one time in the list of all cascading referential actions that result from the DELETE or UPDATE – MSDN When we create an entity data model from the above database, we get the following:   In order to get the Games to be deleted when the Team is deleted, we need to specify End1 OnDelete action of Cascade for the HomeGames and AwayGames associations.   Now, we have an Entity Data Model that accomplishes what we set out to do.  One caveat here is that Entity Framework will only properly handle the cascading delete when the the players and games for the team have been loaded into memory.  For a more detailed look at Cascade Delete in EF Database First, take a look at this blog post by Alex James.   Building The Same Sample with EF Code First Next, we're going to build up the model with the code first approach.  EF Code First is defined on the Ado.Net team blog as such: Code First allows you to define your model using C# or VB.Net classes, optionally additional configuration can be performed using attributes on your classes and properties or by using a Fluent API. Your model can be used to generate a database schema or to map to an existing database. Entity Framework Code First follows some conventions to determine when to cascade delete on a relationship.  More details can be found on MSDN: If a foreign key on the dependent entity is not nullable, then Code First sets cascade delete on the relationship. If a foreign key on the dependent entity is nullable, Code First does not set cascade delete on the relationship, and when the principal is deleted the foreign key will be set to null. The multiplicity and cascade delete behavior detected by convention can be overridden by using the fluent API. For more information, see Configuring Relationships with Fluent API (Code First). Our DbContext consists of 4 DbSets: public DbSet<Team> Teams { get; set; } public DbSet<Player> Players { get; set; } public DbSet<Mascot> Mascots { get; set; } public DbSet<Game> Games { get; set; } When we set the Mascot –> Team relationship to required, Entity Framework will automatically delete the Mascot when the Team is deleted.  This can be done either using the [Required] data annotation attribute, or by overriding the OnModelCreating method of your DbContext and using the fluent API. Data Annotations: public class Mascot { public int Id { get; set; } public string Name { get; set; } [Required] public virtual Team Team { get; set; } } Fluent API: protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Entity<Mascot>().HasRequired(m => m.Team); } The Player –> Team relationship is automatically handled by the Code First conventions. When a Team is deleted, the Team property for all the players on that team will be set to null.  No additional configuration is required, however all the Player entities must be loaded into memory for the cascading to work properly. The Game –> Team relationship causes some grief in our Code First example.  If we try setting the HomeTeam and AwayTeam relationships to required, Entity Framework will attempt to set On Cascade Delete for the HomeTeam and AwayTeam foreign keys when creating the database tables.  As we saw in the database first example, this causes a circular reference error and throws the following SqlException: Introducing FOREIGN KEY constraint 'FK_Games_Teams_AwayTeam_Id' on table 'Games' may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints. Could not create constraint. To solve this problem, we need to disable the default cascade delete behaviour using the fluent API: protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Entity<Mascot>().HasRequired(m => m.Team); modelBuilder.Entity<Team>() .HasMany(t => t.HomeGames) .WithRequired(g => g.HomeTeam) .WillCascadeOnDelete(false); modelBuilder.Entity<Team>() .HasMany(t => t.AwayGames) .WithRequired(g => g.AwayTeam) .WillCascadeOnDelete(false); base.OnModelCreating(modelBuilder); } Unfortunately, this means we need to manually manage the cascade delete behaviour.  When a Team is deleted, we need to manually delete all the home and away Games for that Team. foreach (Game awayGame in jets.AwayGames.ToArray()) { entities.Games.Remove(awayGame); } foreach (Game homeGame in homeGames) { entities.Games.Remove(homeGame); } entities.Teams.Remove(jets); entities.SaveChanges();   Overriding the Defaults – When and How To As you have seen, the default behaviour of Entity Framework Code First can be overridden using the fluent API.  This can be done by overriding the OnModelCreating method of your DbContext, or by creating separate model override files for each entity.  More information is available on MSDN.   Going Further These were simple examples but they helped us illustrate a couple of points. First of all, we were able to demonstrate the default behaviour of Entity Framework when dealing with cascading deletes, specifically how entity relationships affect the outcome. Secondly, we showed you how to modify the code and control the behaviour to get the outcome you're looking for. Finally, we showed you how easy it is to explore this kind of thing, and we're hoping that you get a chance to experiment even further. For example, did you know that: Entity Framework Code First also works seamlessly with SQL Azure (MSDN) Database creation defaults can be overridden using a variety of IDatabaseInitializers  (Understanding Database Initializers) You can use Code Based migrations to manage database upgrades as your model continues to evolve (MSDN) Next Steps There's no time like the present to start the learning, so here's what you need to do: Get up-to-date in Visual Studio 2010 (VS2010 | SP1) or Visual Studio 2012 (VS2012) Build yourself a project to try these concepts out (or download the sample project) Get into the community and ask questions! There are a ton of great resources out there and community members willing to help you out (like these two guys!). Good luck! About the Authors David Paquette works as a lead developer at P2 Energy Solutions in Calgary, Alberta where he builds commercial software products for the energy industry.  Outside of work, David enjoys outdoor camping, fishing, and skiing. David is also active in the software community giving presentations both locally and at conferences. David also serves as the President of Calgary .Net User Group. James Chambers crafts software awesomeness with an incredible team at LogiSense Corp, based in Cambridge, Ontario. A husband, father and humanitarian, he is currently residing in the province of Manitoba where he resists the urge to cheer for the Jets and maintains he allegiance to the Calgary Flames. When he's not active with the family, outdoors or volunteering, you can find James speaking at conferences and user groups across the country about web development and related technologies.

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