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• Various issues linked to my CD drive, when it has a disc in it

  - by Voyagerfan5761

  When I go to the Desktop and click on a media icon (for my flash drive, a CD, whatever it is), the following problems occur, in this approximate sequence: Nautilus will close if it's open. the desktop icons disappear my Window List shows a button that says "Starting File Manager" the icons reappear the button in Window List disappears Because of this problem, I can no longer drag and drop media, nor can I right-click to perform actions such as "Eject" and "Safely Remove Drive". The same symptoms occur if I click a media icon (that is also present on the desktop) in Nautilus' Computer view, though notably not if I click in the places list on the left. I have confirmed that this problem happens only if there is a CD in the drive (Matshita UJDA360). Also, inserting a disc into the CD drive appears to kill all running programs and restart Nautilus (or X; I'm not sure). Applications like Brasero and Rhythmbox will not start while there is a disc in the drive. Removing the disc doesn't result in the list of media updating; it must be forced to update by clicking on one of the desktop icons and going through one of the above-described cycles. It doesn't seem to matter what type of disc is in the drive. This has happened with CD-RWs I burned years ago using Roxio on Windows XP, the Ubuntu disc I installed from (burned with InfraRecorder Portable under Windows XP), and the retail game disc for Star Trek Armada II. The first indication of a problem was Brasero dying when I tried to insert a disc for erasure and rewriting. Since then, I've drafted several different questions on various issues, finally combining them into this one when I realized that having a CD in the drive was the common link. Could this be a simple driver issue? If Ubuntu is dynamically detecting my hardware on boot, can I specify drivers for devices that I know will be a problem if the default files are used? I'm beginning to think that my laptop, an old Dell Inspiron 2650, is just too old or proprietary-driver-hungry (or something, maybe RAM-starved) for Ubuntu and Windows XP to play nicely alongside each other. Or maybe I just need to carefully take my wall-wart machine to a coffee shop for an afternoon so I can download updates and such from the Internet, as I lack a home connection.

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• Sharing one static ip for both ftp and www service

  - by user11496

  Trying to figure out how to update the Zone record and configure webserver so that one application on the webserver is accessible by public. I'm completely not good at NS/DNS/NAT/firewall/routing/port forwarding/networking etc. "faraday" is the intranet name. Everyone within local network can access all applications hosted on "faraday". Hostname for webserver is "www", FTP server is "ftpserver". Both servers running RHEL4 OS. The goal is to allow anyone outside the company network (public) to access only one of the many applications on "faraday". Hope somebody can help me with some of the questions below, if not all. From zoneedit record, the static IP is used by FTP now. Can I use the same existing static IP - 219.95.10.100, for web service? Currently anyone who enter "http://www.abc.com.my" will be directed to "http://www.abc.com". I don't want this to change. Currently, no one else, except employee on local network, can access "faraday" web pages. How to configure so that when anyone type "http://thisapp.abc.com.my" on their web browser, the url will lead them to "http://faraday/thisapp" (application folder is /var/www/html/thisapp on RHEL4 web server). If possible, how to set the URL will continue to show "http://thisapp.abc.com.my" instead of "http://faraday/thisapp" How to limit/restrict user (those who are not from local network) so they only have access to "http://thisapp.abc.com.my", but not "http://faraday" or "http://faraday/anotherapp", etc. What's the configuration changes needed in /etc/httpd.conf on web server? Company domain name is "abc.com.my". Following is the zone records on www.zoneedit.com. Subdomain Type IP sdsl A 219.95.10.100 ftp CNAME sdsl.abc.com.my @ NS ns3.zoneedit.com @ NS ns7.zoneedit.com WebForward record: New Domain Destination Cloaked www.abc.com.my http://www.abc.com N On my local DNS server, there are 2 zone files: abc.com.my and pnmy.abc.com. > cat abc.com.my.zone ftp CNAME ftp.pnmy.abc.com. sdsl A 219.95.10.100 > cat pnmy.abc.com.zone ftp CNAME ftpserver ftpserver A 172.16.5.1 faraday CNAME www www A 172.16.5.2

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• Newsletter sent with drupal goes to Spam Folder [closed]

  - by HerrSerker

  Possible Duplicate: How could I prevent my mail from being recognized as spam? I'm sending a newsletter with drupals simplenews module The website is hosted on an 1und1 server in germany (as seen in in header domains online.de and kundenserver.de) When I send it, it goes to Spam folder in Yahoo & GMail Mailbox, but not in Spam Folder in web.de, hotmail and GMX Mailboxes Here is, what I have in the Mail Header (for yahoo in this example) Received: from 12.345.678.90 (EHLO sXXXXXXXXX.online.de) (12.345.678.90) by mtaXXX.mail.kks.yahoo.co.jp with SMTP; Fri, 15 Jun 2012 18:45:24 +0900 Received: from [127.0.0.1] (helo=infongdXXXXX.rtr.kundenserver.de) by sXXXXXXXXX.online.de with esmtp (Exim 4.72) (envelope-from <[email protected]>) id 1SfT5k-00068r-Q8 for [email protected]; Fri, 15 Jun 2012 11:45:20 +0200 Received: from 83.136.130.41 (IP may be forged by CGI script) by infongdXXXXX.rtr.kundenserver.de with HTTP id 0Z04SW-1SQTKp3LPr-00YxYk; Fri, 15 Jun 2012 11:45:20 +0200 From: SENDER <[email protected]> To: "[email protected]" <[email protected]> Date: Fri, 15 Jun 2012 11:45:20 +0200 Subject: This is the subject of the newsletter Thread-Topic: This is the subject of the newsletter Thread-Index: Ac1K3nT42juzo7uCSkq5dTlby1ZvpQ== List-Unsubscribe: <http://www.example.com/newsletter/confirm/remove/XXXXXXXXX> X-MS-Has-Attach: X-Auto-Response-Suppress: All X-MS-TNEF-Correlator: x-originating-ip: [12.345.678.90] authentication-results: mtaXXX.mail.kks.yahoo.co.jp from=example.com; domainkeys=neutral (no sig); dkim=neutral (no sig) [email protected] errors-to: "SENDER" <[email protected]> received-spf: none (sXXXXXXXXX.online.de: domain of [email protected] does not designate permitted sender hosts) x-apparently-to: [email protected] via 123.45.67.890; Fri, 15 Jun 2012 18:45:25 +0900 x-sender-info: <[email protected]> content-length: 13762 Content-Type: multipart/alternative; boundary="_000_7471797868716571796675707173696675806577726778666766687_" MIME-Version: 1.0 I cannot see any direct spam filter message in this. But I'm kind of stunned by the Received: from 83.136.130.41 (IP may be forged by CGI script) part. After I searched a bit, it seems, that this is a special 'feature' of 1und1 Mail servers. Here are my questions: Is it possible that, if I get rid of the 'Ip maybe forged' part, that the Mail is not regarded as spam anymore? If so, Does anyone know, how I can get rid of it in drupal?

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• Ubuntu 12.04.3 Graphics Issues: Broken Pipes, Reinstalled Xorg and Bumblebee

  - by user190488

  It seems I have a problem, and am only making it worse by following what I find online. I have a new Asus N550JV-D71 (not sure about the part after the dash, though I definitely know it includes 71). I decided to downgrade Windows 8 to 7, then dual boot Ubuntu 12.04 with it (there were issues with Windows 8, and I had a Windows 7 disk handy). It did work and, after installing Bumblebee in tty (because it wouldn't boot when it was first installed), it worked marvelously for a little less than a week. However, I restarted it last night and got the Could not write bytes: Broken pipes error. (I see it's a very common error, but I've looked at the majority of the suggested Similar Questions already.) I followed what I could find online, followed those instructions (making sure to not install any sort of graphics drivers other than what Bumblebee provides), and it just seems to go further and further downhill. I'm afraid I didn't write the exact steps to get to this point (it was late by the time I gave up the night before), but it involved reinstalling lightdm, xorg (and xserver?), and Bumblebee. I then changed the Bumblebee.conf file so that Device=nvidia. I'm pretty new to Linux in general (I've used it since 10.04, but I hadn't had issues up until this computer, so it let me stay a newbie), so I'm not exactly sure what log files to look at to find the errors to look up. However, I did look at lshw and noticed that displays was marked as unassigned. Also, if I try to start lightdm using the command line, it always stops at Stopping Mount network filesystems. I should note that there isn't an xorg.conf file, and no .Xauthority. I would really, really prefer not to reinstall 12.04 if possible. I managed to get grub to display only a short time ago, and I can't boot to the dvd drive unless I go into the BIOS settings and manually change the boot order (that was an issue from the beginning, before the Ubuntu install), and getting into those settings often means rebooting several times due to the fact that the window to get to it is extremely small. I have most of what I need backed up, however, in case it does get to that point. If I really have to, I can just use the latest Ubuntu version instead of the LTS, but the reason I chose 12.04 in the first place is because I need something stable-ish, and Windows isn't suitable to what I need to do. I should note that the reason I restarted last night in the first place was that it wasn't charging the battery, and the wifi kept on going out. Hardware: Nvidia GeForce GT 750M Intel HD graphics 4600

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• ArchBeat Link-o-Rama for July 2, 2013

  - by Bob Rhubart

  One Week To Go: OTN Architect Day: Cloud Computing - July 9, 2013, Redwood Shores, CA. The first OTN Architect Day event of 2013 happens in just one week, on Tuesday July 9 at the Oracle Conference Center in Redwood Shores, CA. Registration is free and you get three sessions by three experts on cloud computing in the real world — plus a panel Q&A for answers to all of your questions. Register now! Oracle Database 12c: Flashback Moving Forward | Lucas Jellema Oracle ACE Director Lucas Jellema's latest of several recent blog posts dealing with various aspects of the recently released Oracle Database 12c. Detroit, Embracing New Auto Technologies, Seeks App Builders This story from the New York Times paints a rosy picture indeed for app developers as the internet of things continues to evolve. Advanced View Criteria Implementation in ADF BC | Andrejus Baranovskis Oracle ACE Director Andrejus Baranovskis' post focuses on advanced declarative View Criteria features. JDeveloper: Showing a Popup when Selecting an af:selectOneRadio | Timo Hahn Oracle ACE Timo Hahn illustrates a use case in which a popup is displayed each time the user clicks on one of the radio buttons of a button group. Can Technology Innovation Save The New York Times? One of the standout keynotes from the recent QCon New York event, this presentation by New York Times Sr. VP/CIO Marc Frons and CTO/VP Rajiv Pant paints a detailed portrait of the complete transformation of an organization -- not just the IT. Enterprise architects will find this particularly interesting. Video: Meet Growing IT Demand for Databases with Private DBaaS Do you understand the difference between traditional database deployment and database as a service? If not, you'll want to check out this video, which includes an overview of Oracle Enterprise Manager's capabilities for rapid deployment of DBaaS. S Webcast: Zero-Downtime Migration to Oracle Exadata Using Oracle GoldenGate: A Customer Case Study Presenters Alok Pareek (VP, Product Management/Development, Oracle Data Integration) and John F. Martin (CEO of Emerging Markets and CTO IQNavigator) discuss how IQNavigator is using Oracle GoldenGate with Oracle Exadata. Free eBook: Building a Database Cloud for Dummies This free quick-reference guide, organized into six short chapters and supplemented with helpful illustrations, provides a clear overview of the cloud and step-by-step instructions on deploying database as a service. (Registration required.) Thought for the Day "My motto is: Live every day to the fullest – in moderation." — Lindsay Lohan (Born July 2, 1986) Source: brainyquote.com

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• What location to put bootloader, when running multiple drives and partition

  - by Matt G

  I have Win8 on my desktop, where a 120G SSD is used to run windows and some select applications, while I have a 2TB HDD to provide basic file storage and where possible, install applications instead of on the SSD. I want to install Ubuntu on a new partition of the HDD (I allocated 300GB, with 5GB swap file). I've used a USB to install the OS, which seemed to have done the job. However, after prompting for a restart, I can no longer boot to ubuntu. During instillation I was confused about where to install the "boot loader instillation". I ended up selecting "/dev/stb" because I figured I would be able to boot with BIOS by selecting the HDD drive as a priority over the SSD. The bootloader is a large part of where I think I went wrong. My partition system looked something like this: /dev/sta ... //SSD ~120 GB /dev/sta1 NTFS (350 MB) //Win8System /dev/sta2 NTFS (118 GB) //Win8C-Drive /dev/stb ... //HDD ~2TB /dev/stb1 NTFS (1563 GB) //FileStorage /dev/stb5 Free Space (300 GB) //Space I want to use for Linux (NOTE: Created two partitions from the 300GB, ~5GB and 295GB. stb5,stb6.) It'd be great if I could get an explanation of what drive you'd select for the boot loader and why, and what selections won't work with regards to the Boot Loader Instillation. I think I understand what Grub is, but I have no idea on how to use it, or play around with it. I seem to be able to get back into OS from my usb, however I believe it's just showing me a preview/trial of Ubuntu (ie, can't access any of the system NTFS drives). Note, if I try to install from the USB again, it will recognize that a version of Ubuntu 13.10 exists on the system. Apologies in advance, have used windows all my life, don't really know to much about Linux at all. Did have a brief skim over some similar questions, didn't find anything too useful. - Where to install bootloader when installing Ubuntu as secondary OS? - ubuntu 12.10 dual boot with windows 8 on two hdds - Dual-boot Windows 7 and Ubuntu on two SSDs with UEFI

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• Push-Based Events in a Services Oriented Architecture

  - by Colin Morelli

  I have come to a point, in building a services oriented architecture (on top of Thrift), that I need to expose events and allow listeners. My initial thought was, "create an EventService" to handle publishing and subscribing to events. That EventService can use whatever implementation it desires to actually distribute the events. My client automatically round-robins service requests to available service hosts which are determined using Zookeeper-based service discovery. So, I'd probably use JMS inside of EventService mainly for the purpose of persisting messages (in the event that a service host for EventService goes down before it can distribute the message to all of the available listeners). When I started considering this, I began looking into the differences between Queues and Topics. Topics unfortunately won't work for me, because (at least for now), all listeners must receive the message (even if they were down at the time the event was pushed, or hadn't made a subscription yet because they haven't completed startup (during deployment, for example) - messages should be queued until the service is available). However, I don't want EventService to be responsible for handling all of the events. I don't think it should have the code to react to events inside of it. Each of the services should do what it needs with a given event. This would indicate that each service would need a JMS connection, which questions the value of having EventService at all (as the services could individually publish and subscribe to JMS directly). However, it also couples all of the services to JMS (when I'd rather that there be a single service that's responsible for determining how to distribute events). What I had thought was to publish an event to EventService, which pulls a configuration of listeners from some configuration source (database, flat file, irrelevant for now). It replicates the message and pushes each one back into a queue with information specific to that listener (so, if there are 3 listeners, 1 event would become 3 events in JMS). Then, another thread in EventService (which is replicated, running on multiple hots) would be pulling from the queue, attempting to make the service call to the "listener", and returning the message to the queue (if the service is down), or discarding the message (if the listener completed successfully). tl;dr If I have an EventService that is responsible for receiving events and delegating service calls to "event listeners," (which are really just endpoints on other services), how should it know how to craft the service call? Should I create a generic "Event" object that is shared among all services? Then, the EventService can just construct this object and pass it to the service call. Or is there a better answer to this problem entirely?

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• Is it evil to model JSON responses to classes when they are mostly smilar?

  - by Aybe

  Here's the problem : While implementing a C# wrapper for an online API (Discogs) I've been faced to a dilemma : quite often the responses returned have mostly similar members and while modeling these responses to classes, some questions surfaces on which way to go would be the best. Example : Querying for a 'release' or a 'master' will return an object that contains an array of 'artist', however these 'artists' do not exactly have the same members. Currently I decided to represent these 'artists' as a single 'Artist' class, against having respective 'ReleaseArtist' and 'MasterArtist' classes which soon becomes very confusing even though another problem arises : when a category (master or release) does not return these members, they will be null. Though it might sound confusing as well I find it less confusing than the former situation as I've tackled the problem by simply not showing null members when visualizing these objects. Is this the right approach to follow ? An example of these differences : public class Artist { public List<Alias> Aliases { get; set; } public string DataQuality { get; set; } public List<Image> Images { get; set; } public string Name { get; set; } public List<string> NameVariations { get; set; } public string Profile { get; set; } public string Realname { get; set; } public string ReleasesUrl { get; set; } public string ResourceUrl { get; set; } public string Uri { get; set; } public List<string> Urls { get; set; } } public class ReleaseArtist { public string Join { get; set; } public string Name { get; set; } public string Anv { get; set; } public string Tracks { get; set; } public string Role { get; set; } public string ResourceUrl { get; set; } public int Id { get; set; } }

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• 2D water with dynamic waves

  - by user1103457

  New Super Mario Bros has really cool 2D water that I'd like to learn how to create. Here's a video showing it. When something hits the water, it creates a wave. There are also constant "background" waves. You can get a good look at the constant waves just after 00:50 when the camera isn't moving. I assume the splashes in NSMB work as in the first part of this tutorial. But in NSMB the water also has constant waves on the surface, and the splashes look very different. Another difference is that in the tutorial, if you create a splash, it first creates a deep "hole" in the water at the origin of the splash. In new super mario bros this hole is absent or much smaller. I am referring to the splashes that the player creates when jumping in and out of the water. How do they create the constant waves and the splashes? I am especially interested in the splashes, and how they work together with the constant waves. I am programming in XNA. I've tried this myself, but couldn't really get it all to work well together. Bonus questions: How do they create the light spots just under the surface of the waves and how do they texture the deeper parts of the water? This is the first time I try to create water like this. EDIT: I assume the constant waves are created using a sine function. The splashes are probably created in a way like in the tutorial. (But they are not the same, so I am still interested in how to make this kind of splashes) But I have a lot of trouble combining those things. I know I can use the sine function to set the height of a specific watercolumn but the splashes are using the speed, to determine the new height. I can't figure out how to combine those. Not that I am not asking how the developers of new super mario bros did this exactly. I am just interested in ways to recreate an effect like it. This week I have an examweek so I don't have time to work on the code. After this week I will spend a lot of time on it. But I am constantly thinking about it, so that's why I will be checking comments etc. I just won't be looking at the code since it might be too time-consuming.

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• Blender to 3ds max to cal3d format

  - by Kaliber64

  There are quite a few questions on cal3d but they are old and don't apply anymore. In Blender(must be 2.49a for python script to work!!!): I have a scene with 7 meshes, 1 armature, 10 bones. I tried going to one mesh to simplify it but doesn't change anything. I found a small blend file that was used for cal3d and it exported just fine. So I tried to copy it's setup with no success. EDIT*8/13/2012 In the last week here is what I have found so far. I made the mesh in the newest blender(2.62?) and exported it to import it in the old one(2.49a). Did an animation in the old one because importing new blend files to old blenders, its just said it would lose keyframe data and all was good. And then you get the last problem of it not exporting meshes. BUT I found that meshes made in the old one export regardless. I can't find any that won't export. So if I used the old blender to remake my model I could get it to export :) At this point I found a modified release of cal3d (because the most core model variable would not initiate as I made a really small test subject in old blender instead of remaking my big one which took 4 hours.) which fixes the morph objects and adds what cal3d left off with. Under their license they have to release the modification but it has no documentation so I have to figure it out on my own. Its mostly the same. But with this lib it came with a 3ds max exporter. My question now is how do I transfer armature and mesh information from blender to 3ds max in order to export into cal3d format. Every time I try the models are see through and small and there are no bones. The formats I have tried to import are .3ds .obj(mesh only) and COLLADA. In all of them the mesh is invisible and no bones. It says the default texture is on so I should be able to see it. All the vertices are present I found a vertex highlighter so I can see those. If any of this is confusing let me know so I can clear it up. Its late .<=sleep.

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• Impressions from VMworld - Clearing up Misconceptions

  - by Monica Kumar

  Gorgeous sunny weather…none of the usual summer fog…the Oracle Virtualization team has been busy at VMworld in San Francisco this week. From the time exhibits opened on Sunday, our booth staff was fully engaged with visitors. It was great to meet with customers and prospects, and there were many…most with promises to meet again in October at Oracle OpenWorld 2012. Interests and questions ran the gamut - from implementation details to consolidating applications to how does Oracle VM enable rapid application deployment to Oracle support and licensing. All good stuff! Some inquiries are poignant and really help us get at the customer pain points. Some are just based on misconceptions. We’d like to address a couple of common misconceptions that we heard: 1) Rapid deployment of enterprise applications is great but I don’t do this all the time. So why bother? While production applications don’t get updated or upgraded as often, development and QA staging environments are much more dynamic. Also, in today’s Cloud based computing environments, end users expect an entire solution, along with the virtual machine, to be provisioned instantly, on-demand, as and when they need to scale. Whether it’s adding a new feature to meet customer demands or updating applications to meet business/service compliance, these environments undergo change frequently. The ability to rapidly stand up an entire application stack with all the components such as database tier, mid-tier, OS, and applications tightly integrated, can offer significant value. Hand patching, installation of the OS, application and configurations to ensure the entire stack works well together can take days and weeks. Oracle VM Templates provide a much faster path to standing up a development, QA or production stack in a matter of hours or minutes. I see lots of eyes light up as we get to this point of the conversation. 2) Oracle Software licensing on VMware vSphere In the world of multi-vendor IT stacks, understanding license boundaries and terms and conditions for each product in the stack can be challenging.  Oracle’s licensing, though, is straightforward.  Oracle software is licensed per physical processor in the server or cluster where the Oracle software is installed and/or running.  The use of third party virtualization technologies such as VMware is not allowed as a means to change the way Oracle software is licensed.  Exceptions are spelled out in the licensing document labeled “Hard Partitioning". Here are some fun pictures! Visitors to our booth told us they loved the Oracle SUV courtesy shuttles that are helping attendees get to/from hotels. Also spotted were several taxicabs sporting an Oracle banner! Stay tuned for more highlights across desktop and server virtualization as we wrap up our participation at VMworld.

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• What should filenames and URLs of images contain for SEO benefit?

  - by Baumr

  We know that good site architecture usually looks like this: example-company.com/ example-company.com/about/ example-company.com/contact/ example-company.com/products/ example-company.com/products/category/ example-company.com/products/category/productname/ Now, when it comes to Google Image search, it is clear that the img alt tag, filename/URL, and surrounding text (captions, headings, paragraphs) have an effect on ranking. I want to ask about the filename of the images that we should use (e.g. product-photo.jpg). ...but first about the URL: Often web developers stick all images in a single folder in the root: example-company.com/img/ — and I have stopped doing that. (I don't want to get into it, but basically, it seems more semantic for images which make up part of the content at each sub-directory) However, when all images appear in a folder, I feel that their filename needs to reflect what they are a bit more than usual, for example: example-company.com/img/example-company-productname-category.jpg It's a longer filename than just product.png, but as long as it's relevant, I see no problem with regards to SEO (unless you're keyword stuffing), and it could even help rank for keywords: "example company" "productname" "category" So no questions there. But what about when we have places images in the site architecture we outlined at the beginning? In other words, what if image URL paths look like this: example-company.com/products/category/productname/productname.jpg My question is, should the URL be kept short like above and only have the "productname" (and some descriptive keywords) as part of it's filename? Or, should it also include the "example-company" and "category"? Like so: example-company.com/products/category/productname/example-company-category-productname.jpg That seems much longer, and redundant when we look at the URL, but here are a few considerations. Images are often downloaded onto computers, and, to the average user, they lose their original URL and thus — it isn't clear where they came from. Also, some social networks, forums, and other platforms leave the filename intact when uploaded. (Many others rewrite it, for example, Pinterest and Facebook.) Another consideration, will this really help (even if ever so slightly) rank in Google Image Search, or at least inform Google that the product is something specific to the "example-company"? For example, what if this product can only be bought at this store and is the flagship product? In addition to an abundance of internal links to this product page, would having the "example company" name and "category" help it appear in "example company" searches? In other words, is less more?

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• The Case of the Missing Date/Time Stamp: Reporting Services 2008 R2 Snapshots

  - by smisner

  This week I stumbled upon an undocumented “feature” in SQL Server 2008 R2 Reporting Services as I was preparing a demonstration on how to set up and use report snapshots. If you’re familiar with the main changes in this latest release of Reporting Services, you probably already know that Report Manager got a facelift this time around. Although this facelift was generally a good thing, one of the casualties – in my opinion – is the loss of the snapshot label that served two purposes… First, it flagged the report as a snapshot. Second, it let you know when that snapshot was created. As part of my standard operating procedure when demonstrating report snapshots, I point out this label, so I was rather taken aback when I didn’t see it in the demonstration I was preparing. It sort of upset my routine, and I’m rather partial to my routines. I thought perhaps I wasn’t looking in the right place and changed Report Manager from Tile View to Detail View, but no – that label was still missing. In the grand scheme of life, it’s not an earth-shattering change, but you’ll have to look at the Modified Date in Details View to know when the snapshot was run. Or hope that the report developer included a textbox to show the execution time in the report. (Hint: this is a good time to add this to your list of report development best practices, whether a report gets set up as a report snapshot or not!) A snapshot from the past In case you don’t remember how a snapshot appeared in Report Manager back in the old days (of SQL Server 2008 and earlier), here’s an image I snagged from my Reporting Services 2008 Step by Step manuscript: A snapshot in the present A report server running in SharePoint integrated mode had no such label. There you had to rely on the Report Modified date-time stamp to know the snapshot execution time. So I guess all platforms are now consistent. Here’s a screenshot of Report Manager in the 2008 R2 version. One of these is a snapshot and the rest execute on demand. Can you tell which is the snapshot? Consider descriptions as an alternative So my report snapshot demonstration has one less step, and I’ll need to edit the Denali version of the Step by Step book. Things are simpler this way, but I sure wish we had an easier way to identify the execution methods of the reports. Consider using the description field to alert users that the report is a snapshot. It might save you a few questions about why the data isn’t up-to-date if the users know that something changed in the source of the report. Notice that the full description doesn’t display in Tile View, so keep it short and sweet or instruct users to open Details View to see the entire description.

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• SQL: empty string vs NULL value

  - by Jacek Prucia

  I know this subject is a bit controversial and there are a lot of various articles/opinions floating around the internet. Unfortunatelly, most of them assume the person doesn't know what the difference between NULL and empty string is. So they tell stories about surprising results with joins/aggregates and generally do a bit more advanced SQL lessons. By doing this, they absolutely miss the whole point and are therefore useless for me. So hopefully this question and all answers will move subject a bit forward. Let's suppose I have a table with personal information (name, birth, etc) where one of the columns is an email address with varchar type. We assume that for some reason some people might not want to provide an email address. When inserting such data (without email) into the table, there are two available choices: set cell to NULL or set it to empty string (''). Let's assume that I'm aware of all the technical implications of choosing one solution over another and I can create correct SQL queries for either scenario. The problem is even when both values differ on the technical level, they are exactly the same on logical level. After looking at NULL and '' I came to a single conclusion: I don't know email address of the guy. Also no matter how hard i tried, I was not able to sent an e-mail using either NULL or empty string, so apparently most SMTP servers out there agree with my logic. So i tend to use NULL where i don't know the value and consider empty string a bad thing. After some intense discussions with colleagues i came with two questions: am I right in assuming that using empty string for an unknown value is causing a database to "lie" about the facts? To be more precise: using SQL's idea of what is value and what is not, I might come to conclusion: we have e-mail address, just by finding out it is not null. But then later on, when trying to send e-mail I'll come to contradictory conclusion: no, we don't have e-mail address, that @!#$ Database must have been lying! Is there any logical scenario in which an empty string '' could be such a good carrier of important information (besides value and no value), which would be troublesome/inefficient to store by any other way (like additional column). I've seen many posts claiming that sometimes it's good to use empty string along with real values and NULLs, but so far haven't seen a scenario that would be logical (in terms of SQL/DB design). P.S. Some people will be tempted to answer, that it is just a matter of personal taste. I don't agree. To me it is a design decision with important consequences. So i'd like to see answers where opion about this is backed by some logical and/or technical reasons.

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• REL ME tag - trying to figure it out

  - by nekdo

  Regarding http://support.google.com/webmasters/bin/answer.py?hl=en&answer=1229920 to scrolled down section ''Examples'' to the point ''1.'' to the second code line which is: <a rel="me" href="https://plus.google.com/105240469625818678725/"> <img src="//www.google.com/images/icons/ui/gprofile_button-16.png"></a> On the page says that I have to add this line to the Contact Me page of own website in order to get Google Profile button. Exact code which one should be copy and pasted I am able to get here: http://www.google.com/webmasters/profilebutton/ Questions: 1). As you can see on the second URL, to make Google Profile button I need to use "author" tag and not "me" tag. But the first URL which I showed (the line in this message above) shows that I have to use "me" tag and even without this: width="32" height="32". I am already aware that I have to type (second URL) my own Google Profile URL. So do I just MANUALLY ( ! ) change this: <a rel="author" href="https://profiles.google.com/109412257237874861202"> <img src="http://www.google.com/images/icons/ui/gprofile_button-32.png" width="32" height="32"></a> to this (note: two changes done): <a rel="me" href="https://profiles.google.com/109412257237874861202"> <img src="http://www.google.com/images/icons/ui/gprofile_button-32.png"></a> Is this correct? I assume that plus.google.com is the same as profiles.google.com (both is URL of Google Profile). 2). If I was wrong with my first question then the second answer probably won't be even useful but still: Where exactly should I paste the code: <a rel="me" href="https://profiles.google.com/109412257237874861202"> <img src="http://www.google.com/images/icons/ui/gprofile_button-32.png"></a> inside Author Page of own website? I think it doesn't matter where. Also: will this icon be for sure enough or do I also have to make such anchor text with rel me in a ''shape'' of text (for word sentence such as ''Look At My Google Profile'')? Or is just icon really enough? 3). In the same section (''1.'') of the same page (link [first one] provided above) it says that I need to use first author tag to link to Author/Contact Me page of own website in order to later use Me tag. But I think in the explanation is little mistake. Shouldn't be instead of: <a rel="author" href="http://www.cnet.com/profile/iamjaygreene/">Jay Greene</a> this: <a rel="author" href="http://www.cnet.com/profile/iamjaygreene.html">Jay Greene</a> ?

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• ArchBeat Facebook Friday: Top 10 Shared Links - May 23-29, 2014

  - by OTN ArchBeat

  Among the 5,144 fans of the OTN ArchBeat Facebook Page the following Top 10 items were the most popular over the last seven days, May 23-29, 2014. GlassFish/Java EE Community Open Forum Today! | Reza Rahman Have questions about Glassfish? Java EE/GlassFish evangelist Reza Rahman has answers, and you can pick his brain tomorrow during an online forum organized by the London Glassfish User Group and C2B2. The event is free, but you must register in order to participate. Click the link for more information. Twitter Tuesday - Top 10 @ArchBeat Tweets - May 20-26, 2014 The top 10 @OTNArchBeat tweets for the week of May 20-26, 2014. Topics covered include ADF, Cloud, GoldenGate, KScope14, OBIEE, ODI, WebLogic, WebCenter, and more. FrameworkFolders Support has come to Oracle WebCenter Portal | JayJay Zheng Interested in working with Framework Folders in Oracle WebCenter Portal? Oracle ACE JayJay Zheng reviews the essentials. Video: Programming Best Practices - ADF Business Components | Frank Nimphius Frank Nimphius discusses best practices and recommendations for ADF Business Components in the latest video from ADF Architecture TV. Video: Kscope 2014 Preview: Data Modeling and Moving Meditation with Kent Graziano For your mind and your body! Oracle ACE Director Kent Graziano previews his Kscope 2014 data modeling presentations and the early morning Chi Gung sessions he will once again lead for Kscope attendees. OAG and OES Integration for Web API Security: skin and guts | Andre Correa A-Team architect Andre Correa's post examines a strategy for web API security that uses OAG (Oracle API Gateway) and OES (Oracle Entitlements Server). Getting Started with Coherence*Web in WebLogic Server 12.1.2 | Tim Middleton Solution architect Tim Middleton shows you how to configure Coherence*Web in WebLogic Server 12.1.2 and deploy a basic web application. SOA and Business Processes: You are the Process! Part of the 13-part "Industrial SOA" article series, this article looks at best practices for modeling and managing effective business processes. Authentication in Oracle Identity Federation/ IdP | Damien Carru Damien Carru discuss authentication when OIF acts as an IdP and how the server can be configured to use specific OAM Authentication Schemes to challenge the user. Caveats on Using WebLogic Server with JDK7 | JayJay Zheng Quick tech tips from Oracle ACE JayJay Zheng.

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• How to discriminate from two nodes with identical frequencies in a Huffman's tree?

  - by Omega

  Still on my quest to compress/decompress files with a Java implementation of Huffman's coding (http://en.wikipedia.org/wiki/Huffman_coding) for a school assignment. From the Wikipedia page, I quote: Create a leaf node for each symbol and add it to the priority queue. While there is more than one node in the queue: Remove the two nodes of highest priority (lowest probability) from the queue Create a new internal node with these two nodes as children and with probability equal to the sum of the two nodes' probabilities. Add the new node to the queue. The remaining node is the root node and the tree is complete. Now, emphasis: Remove the two nodes of highest priority (lowest probability) from the queue Create a new internal node with these two nodes as children and with probability equal to the sum of the two nodes' probabilities. So I have to take two nodes with the lowest frequency. What if there are multiple nodes with the same low frequency? How do I discriminate which one to use? The reason I ask this is because Wikipedia has this image: And I wanted to see if my Huffman's tree was the same. I created a file with the following content: aaaaeeee nnttmmiihhssfffouxprl And this was the result: Doesn't look so bad. But there clearly are some differences when multiple nodes have the same frequency. My questions are the following: What is Wikipedia's image doing to discriminate the nodes with the same frequency? Is my tree wrong? (Is Wikipedia's image method the one and only answer?) I guess there is one specific and strict way to do this, because for our school assignment, files that have been compressed by my program should be able to be decompressed by other classmate's programs - so there must be a "standard" or "unique" way to do it. But I'm a bit lost with that. My code is rather straightforward. It literally just follows Wikipedia's listed steps. The way my code extracts the two nodes with the lowest frequency from the queue is to iterate all nodes and if the current node has a lower frequency than any of the two "smallest" known nodes so far, then it replaces the highest one. Just like that.

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• ArchBeat Link-o-Rama for 2012-09-05

  - by Bob Rhubart

  OTN Architect Day - Boston - Sept 12: What to Expect If you've never attended an OTN Architect Day, here's a little preview. You start with a continental breakfast. Then you have keynotes by an Oracle expert, and a member of the Oracle ACE community. After that come the break-out sessions, so you have your choice of two sessions in each time slot. So you'll get in two breakouts before lunch. Then you eat. After that there's a panel Q&A during which the audience tosses questions at the assembled session speakers. Then it's on to another set of break-out sessions, followed by a short break. Then the audience breaks into small groups for round table discussions. After that there's a drawing for some cool prizes, followed by the cocktail reception. All that costs you absolutely zero. Register now. Starting and Stopping Fusion Applications the Right Way | Ronaldo Viscuso While the fastartstop tool that ships with Oracle Fusion Applications does most of the work to start/stop/bounce the Fusion Apps environment, it does not do it all. Oracle Fusion Applications A-Team blogger Ronaldo Viscuso's post "aims to explain all tasks involved in starting and stopping a Fusion Apps environment completely." Dodeca Customer Feedback - The Rosewood Company | Tim Tow Oracle ACE Director Tim Tow shares anecdotal comments from one of his clients, a company that is deploying Dodeca to replace an aging VBA/Essbase application. Configuring UCM cache to check for external Content Server changes | Martin Deh Oracle WebCenter and ADF A-Team blogger Martin Deh shares the background information and the solution to a recently encountered customer scenario. Proxy As Upgrade to 11g Does Not Like NQSession.User | Art of Business Intelligence "In Oracle BI 10g the application was a lot more tolerant of bad design and cavalier usage of variables," observes Oracle ACE Christian Screen. "We noticed an issue recently during an upgrade where the Proxy As configuration in Oracle BI 10g used the NQSession.User variable to identify the user logged into Presentation Servers acting as Proxy." Oracle WebLogic Server 11g: Interactive Quick Reference | Dirk Nachbar Oracle ACE Dirk Nachbar shares a quick post with information on a new interactive reference guide to Oracle WebLogic Server. "The Quick Reference shows you an architecural overview of the Oracle WebLogic Server processes, tools, configuration files, log files and so on including a short description of each section and the corresponding link to the Oracle WebLogic Server Documentation," says Nachbar. Thought for the Day "In fast moving markets, adaptation is significantly more important than optimization." — Larry Constantine Source: Quotes for Software Engineers

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• Why is my dual-boot Ubuntu partition showing up as a peripheral "root.disk"?

  - by Don

  I recently installed Ubuntu 12.04, which I had been booting from a usb key, as a dual-boot on my machine running Windows 7. From what I had read online while researching, I was prepared to have to shrink the Windows partition and all that. But I never had to - it really was just a few clicks here and there and it was installed. I'm still pretty confused about it, but whatever, it worked, and the two peacefully coexist on my machine, and I have broken things to fix before I worry about fixing unbroken things. So yesterday I got it in my head to look at my partitions (I was considering making an all new partition to install the Windows 8 Release Preview). What I saw confused me. Here's a screenshot of the disk utility. At this moment, there is nothing connected to my computer, and nothing in any of the optical drives/ports/card readers/etc. Can you help me figure out what's going on here? Don's Machine is, I believe, my Windows partition - that's the name I assigned my machine from Windows Explorer. PQSERVICE is from what I can find online also Windows, but having to do with backup. And SYSTEM REQUIRED, if I browse it in Ubuntu, is definitely something to do with booting, and I believe it is also Windows'. According to the sizes shown, those three together should use up my 500 GB HD. Then further down, as a "peripheral device", it lists that 31 GB disk. This is obviously my Ubuntu (Model:Linux Loop:root.disk), but why is it showing up as a peripheral? So, to sum up those questions and to add some more random ones I had: Why is Ubuntu showing up as a peripheral device? If the Windows sections take up all 500 GB, where does Ubuntu live? If I renamed the disk partitions, would my life become a nightmare (seriously - can I safely rename them)? Why didn't I have to resize the Windows partition in the first place? Would giving Ubuntu more space improve its performance (it hangs alot)? Is it possible to have a partition for each OS (Windows 7 & 8, Ubuntu), a partition for files, and a separate partition for backups? Is this towards the good or bad idea end of the spectrum? @Elfy, would that explain why it keeps hanging? I guess I'll backup my files, rip it out, and reinstall it correctly later on today.

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• Survey results: Open source developer preferences

  We recently conducted a survey of open source developers to learn about their current preferences around hosting sites and source control systems.  The survey was primarily advertised via Twitter, and we tried to avoid pushing the survey among audiences that would be specifically oriented towards a particular site (for example we did not advertise the survey from the CodePlex twitter account). In total there were just under 500 responses, so a reasonable sample size although not necessarily enough to guarantee fully representative results.  One of the survey questions was what is your preferred operating system for development, and looking at the results they are particularly interesting when split by operating system preference because of how significant the difference is:   Table 1 - Preferences by what is preferred operating system for development   As you can see, the preferences among developers which prefer Windows is very different from Linux and Mac oriented developers.  Again, the question was on what operating system they prefer to use for development, and didn’t ask what type of applications they create, so presumably many create things like websites which are cross-platform from a user perspective regardless of the operating system they prefer developing with. For hosting site preference, CodePlex and GitHub are roughly tied for first place among Windows developers and combined are preferred by over 75%.  However with Linux and Mac developers, GitHub has a runaway lead over the other sites.  Perhaps not particularly surprising, CodePlex has negligible mindshare among Linux and Mac developers.  It is somewhat surprising how low SourceForge and Google Code are given historically they used to rank much higher. Looking at version control preferences is also interesting.  Among Windows developers TFS, Mercurial, Subversion, and Git all have a sizable following.  While for Linux and Mac developers it is almost all Git and Mercurial, with Git having a substantial lead.  Git is generally considered to run better on Linux and have more of a Unix feel, so not really surprising to see it more popular there compared to Windows developers.  It is surprising how low Subversion has dropped since it was the dominant preference not long ago for open source developers.  Around a quarter of Windows developers still prefer Subversion, but Linux and Mac developers have largely abandoned it.  The trend towards distributed version control systems (e.g. Mercurial and Git) is strong, with over 50% of Windows developers now prefer DVCS, and over 80% of Linux and Mac developers.

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• Ray Intersecting Plane Formula in C++/DirectX

  - by user4585

  I'm developing a picking system that will use rays that intersect volumes and I'm having trouble with ray intersection versus a plane. I was able to figure out spheres fairly easily, but planes are giving me trouble. I've tried to understand various sources and get hung up on some of the variables used within their explanations. Here is a snippet of my code: bool Picking() { D3DXVECTOR3 vec; D3DXVECTOR3 vRayDir; D3DXVECTOR3 vRayOrig; D3DXVECTOR3 vROO, vROD; // vect ray obj orig, vec ray obj dir D3DXMATRIX m; D3DXMATRIX mInverse; D3DXMATRIX worldMat; // Obtain project matrix D3DXMATRIX pMatProj = CDirectXRenderer::GetInstance()->Director()->Proj(); // Obtain mouse position D3DXVECTOR3 pos = CGUIManager::GetInstance()->GUIObjectList.front().pos; // Get window width & height float w = CDirectXRenderer::GetInstance()->GetWidth(); float h = CDirectXRenderer::GetInstance()->GetHeight(); // Transform vector from screen to 3D space vec.x = (((2.0f * pos.x) / w) - 1.0f) / pMatProj._11; vec.y = -(((2.0f * pos.y) / h) - 1.0f) / pMatProj._22; vec.z = 1.0f; // Create a view inverse matrix D3DXMatrixInverse(&m, NULL, &CDirectXRenderer::GetInstance()->Director()->View()); // Determine our ray's direction vRayDir.x = vec.x * m._11 + vec.y * m._21 + vec.z * m._31; vRayDir.y = vec.x * m._12 + vec.y * m._22 + vec.z * m._32; vRayDir.z = vec.x * m._13 + vec.y * m._23 + vec.z * m._33; // Determine our ray's origin vRayOrig.x = m._41; vRayOrig.y = m._42; vRayOrig.z = m._43; D3DXMatrixIdentity(&worldMat); //worldMat = aliveActors[0]->GetTrans(); D3DXMatrixInverse(&mInverse, NULL, &worldMat); D3DXVec3TransformCoord(&vROO, &vRayOrig, &mInverse); D3DXVec3TransformNormal(&vROD, &vRayDir, &mInverse); D3DXVec3Normalize(&vROD, &vROD); When using this code I'm able to detect a ray intersection via a sphere, but I have questions when determining an intersection via a plane. First off should I be using my vRayOrig & vRayDir variables for the plane intersection tests or should I be using the new vectors that are created for use in object space? When looking at a site like this for example: http://www.tar.hu/gamealgorithms/ch22lev1sec2.html I'm curious as to what D is in the equation AX + BY + CZ + D = 0 and how does it factor in to determining a plane intersection? Any help will be appreciated, thanks.

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• How can I make a universal construction more efficient?

  - by VF1

  A "universal construction" is a wrapper class for a sequential object that enables it to be linearized (a strong consistency condition for concurrent objects). For instance, here's an adapted wait-free construction, in Java, from [1], which presumes the existence of a wait-free queue that satisfies the interface WFQ (which only requires one-time consensus between threads) and assumes a Sequential interface: public interface WFQ<T> // "FIFO" iteration { int enqueue(T t); // returns the sequence number of t Iterable<T> iterateUntil(int max); // iterates until sequence max } public interface Sequential { // Apply an invocation (method + arguments) // and get a response (return value + state) Response apply(Invocation i); } public interface Factory<T> { T generate(); } // generate new default object public interface Universal extends Sequential {} public class SlowUniversal implements Universal { Factory<? extends Sequential> generator; WFQ<Invocation> wfq = new WFQ<Invocation>(); Universal(Factory<? extends Sequential> g) { generator = g; } public Response apply(Invocation i) { int max = wfq.enqueue(i); Sequential s = generator.generate(); for(Invocation invoc : wfq.iterateUntil(max)) s.apply(invoc); return s.apply(i); } } This implementation isn't very satisfying, however, since it presumes determinism of a Sequential and is really slow. I attempted to add memory recycling: public interface WFQD<T> extends WFQ<T> { T dequeue(int n); } // dequeues only when n is the tail, else assists other threads public interface CopyableSequential extends Sequential { CopyableSequential copy(); } public class RecyclingUniversal implements Universal { WFQD<CopyableSequential> wfqd = new WFQD<CopyableSequential>(); Universal(CopyableSequential init) { wfqd.enqueue(init); } public Response apply(Invocation i) { int max = wfqd.enqueue(i); CopyableSequential cs = null; int ctr = max; for(CopyableSequential csq : wfq.iterateUntil(max)) if(--max == 0) cs = csq.copy(); wfqd.dequeue(max); return cs.apply(i); } } Here are my specific questions regarding the extension: Does my implementation create a linearizable multi-threaded version of a CopyableSequential? Is it possible extend memory recycling without extending the interface (perhaps my new methods trivialize the problem)? My implementation only reduces memory when a thread returns, so can this be strengthened? [1] provided an implementation for WFQ<T>, not WFQD<T> - one does exist, though, correct? [1] Herlihy and Shavit, The Art of Multiprocessor Programming.

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• determine collision angle on a rotating body

  - by jorb

  update: new diagram and updated description I have a contact listener set up to try and determine the side that a collision happened at relative to the a bodies rotation. One way to solve this is to find the value of the yellow angle between the red and blue vectors drawn above. The angle can be found by taking the arc cosine of the dot product of the two vectors (Evan pointed this out). One of my points of confusion is the difference in domain of the atan2 function html canvas coordinates and the Box2d rotation information. I know I have to account for this somehow... SS below questions: Does Box2D provide these angles more directly in the collision information? Am I even on the right track? If so, any hints? I have the following javascript so far: Ship.prototype.onCollide = function (other_ent,cx,cy) { var pos = this.body.GetPosition(); //collision position relative to body var d_cx = pos.x - cx; var d_cy = pos.y - cy; //length of initial vector var len = Math.sqrt(Math.pow(pos.x -cx,2) + Math.pow(pos.y-cy,2)); //body angle - can over rotate hence mod 2*Pi var ang = this.body.GetAngle() % (Math.PI * 2); //vector representing body's angle - same magnitude as the first var b_vx = len * Math.cos(ang); var b_vy = len * Math.sin(ang); //dot product of the two vectors var dot_prod = d_cx * b_vx + d_cy * b_vy; //new calculation of difference in angle - NOT WORKING! var d_ang = Math.acos(dot_prod); var side; if (Math.abs(d_ang) < Math.PI/2 ) side = "front"; else side = "back"; console.log("length",len); console.log("pos:",pos.x,pos.y); console.log("offs:",d_cx,d_cy); console.log("body vec",b_vx,b_vy); console.log("body angle:",ang); console.log("dot product",dot_prod); console.log("result:",d_ang); console.log("side",side); console.log("------------------------"); }

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• Accessing SQL Server data from iOS apps

  - by RobertChipperfield

  Almost all mobile apps need access to external data to be valuable. With a huge amount of existing business data residing in Microsoft SQL Server databases, and an ever-increasing drive to make more and more available to mobile users, how do you marry the rather separate worlds of Microsoft's SQL Server and Apple's iOS devices? The classic answer: write a web service layer Look at any of the questions on this topic asked in Internet discussion forums, and you'll inevitably see the answer, "just write a web service and use that!". But what does this process gain? For a well-designed database with a solid security model, and business logic in the database, writing a custom web service on top of this just to access some of the data from a different platform seems inefficient and unnecessary. Desktop applications interact with the SQL Server directly - why should mobile apps be any different? The better answer: the iSql SDK Working along the lines of "if you do something more than once, make it shared," we set about coming up with a better solution for the general case. And so the iSql SDK was born: sitting between SQL Server and your iOS apps, it provides the simple API you're used to if you've been developing desktop apps using the Microsoft SQL Native Client. It turns out a web service remained a sensible idea: HTTP is much more suited to the Big Bad Internet than SQL Server's native TDS protocol, removing the need for complex configuration, firewall configuration, and the like. However, rather than writing a web service for every app that needs data access, we made the web service generic, serving only as a proxy between the SQL Server and a client library integrated into the iPhone or iPad app. This client library handles all the network communication, and provides a clean API. OSQL in 25 lines of code As an example of how to use the API, I put together a very simple app that allowed the user to enter one or more SQL statements, and displayed the results in a rather primitively formatted text field. The total amount of Objective-C code responsible for doing the work? About 25 lines. You can see this in action in the demo video. Beta out now - your chance to give us your suggestions! We've released the iSql SDK as a beta on the MobileFoo website: you're welcome to download a copy, have a play in your own apps, and let us know what we've missed using the Feedback button on the site. Software development should be fun and rewarding: no-one wants to spend their time writing boiler-plate code over and over again, so stop writing the same web service code, and start doing exciting things in the new world of mobile data!

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• Playing with F#

  - by mroberts

  Project Euler is a awesome site.   When working with a new language it can be tricky to find problems that need solving, that are more complex than "Hello World" and simpler than a full blown application. Project Euler gives use just that, cool and thought provoking problems that usually don't take days to solve.  I've solved a number of questions with C# and some with Java.  BTW, I used Java because it had BigInteger support before .Net. A couple weeks ago, back when winter had a firm grip on Columbus, OH, I began playing (researching) with F#.  I began with Problem #1 from Project Euler.  I started by looking at my solution in C#. Here is my solution in C#. 1: using System; 2: using System.Collections.Generic; 3:   4: namespace Problem001 5: { 6: class Program 7: { 8: static void Main(string[] args) 9: { 10: List<int> values = new List<int>(); 11:   12: for (int i = 1; i < 1000; i++) 13: { 14: if (i % 3 == 0 || i % 5 == 0) 15: values.Add(i); 16: } 17: int total = 0; 18:   19: values.ForEach(v => total += v); 20:   21: Console.WriteLine(total); 22: Console.ReadKey(); 23: } 24: } 25: }   Now, after much tweaking and learning, here is my solution in F#.   1: open System 2:   3: let calc n = 4: [1..n] 5: |> List.map (fun x -> if (x % 3 = 0 || x % 5 = 0) then x else 0) 6: |> List.sum 7:   8: let main() = 9: calc 999 10: |> printfn "result = %d" 11: Console.ReadKey(true) |> ignore 12:   13: main() Just this little example highlights some cool things about F#. Type inference. F# infers the type of a value.  In the C# code above we declare a number of variables, the list, and a couple ints.  F# does not require this, it infers the calc (a function) accepts a int and returns a int. Great built in functionality for Lists.  List.map for example. BTW, I don’t think I’m spilling the beans by giving away the code for Problem 1.  It by far is the easiest question, IMHO, solved by 92,000+ people. Next I’ll look into writing a class library with F#.

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