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  • SQLAuthority News – Why VoIP Service Providers Should Think About NuoDB’s Geo Distribution

    - by Pinal Dave
    You can always tell when someone’s showing off their cool, cutting edge comms technology. They tend to raise their voice a lot. Back in the day they’d announce their gadget leadership to the rest of the herd by shouting into their cellphone. Usually the message was no more urgent than “Hi, I’m on my cellphone!” Now the same types will loudly name-drop a different technology to the rest of the airport lounge. “I’m leveraging the wifi,” a fellow passenger bellowed, the other day, as we filtered through the departure gate. Nobody needed to know that, but the subtext was “look at me everybody”. You can tell the really advanced mobile user – they tend to whisper. Their handset has a microphone (how cool is that!) and they know how to use it. Sometimes these shouty public broadcasters aren’t even connected anyway because the database for their Voice over IP (VoIP) platform can’t cope. This will happen if they are using a traditional SQL model to try and cope with a phone network which has far flung offices and hundreds of mobile employees. That, like shouting into your phone, is just wrong on so many levels. What VoIP needs now is a single, logical database across multiple servers in different geographies. It needs to be updated in real-time and automatically scaled out during times of peak demand. A VoIP system should scale up to handle increased traffic, but just as importantly is must then go back down in the off peak hours. Try this with a MySQL database. It can’t scale easily enough, so it will keep your developers busy. They’ll have spent many hours trying to knit the different databases together. Traditional relational databases can possibly achieve this, at a price. Mind you, you could extend baked bean cans and string to every point on the network and that would be no less elegant. That’s not really following engineering principles though is it? Having said that, most telcos and VoIP systems use a separate, independent solution for each office location, which they link together – loosely.  The more office locations, the more complex and expensive the solution becomes and so the more you spend on maintenance. Ideally, you’d have a fluid system that can automatically shift its shape as the need arises. That’s the point of software isn’t it – it adapts. Otherwise, we might as well return to the old days. A MySQL system isn’t exactly baked bean cans attached by string, but it’s closer in spirit to the old many teethed mechanical beast that was employed in the first type of automated switchboard. NuoBD’s NewSQL is designed to be a single database that works across multiple servers, which can scale easily, and scale on demand. That’s one system that gives high connectivity but no latency, complexity or maintenance issues. MySQL works in some circumstances, but a period of growth isn’t one of them. So as a company moves forward, the MySQL database can’t keep pace. Data storage and data replication errors creep in. Soon the diaspora of offices becomes a problem. Your telephone system isn’t just distributed, it is literally all over the place. Though voice calls are often a software function, some of the old habits of telephony remain. When you call an engineer out, some of them will listen to what you’re asking for and announce that it cannot be done. This is what happens if you ask, say, database engineers familiar with Oracle or Microsoft to fulfill your wish for a low maintenance system built on a single, fluid, scalable database. No can do, they’d say. In fact, I heard one shouting something similar into his VoIP handset at the airport. “I can’t get on the network, Mac. I’m on MySQL.” You can download NuoDB from here. “NuoDB provides the ability to replicate data globally in real-time, which is not available with any other product offering,” states Weeks.  “That alone is remarkable and it works. I’ve seen it. I’ve used it.  I’ve tested it. The ability to deploy NuoDB removes a tremendous burden from our support and engineering teams.” Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: NuoDB

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  • Company Review: Google Products

    Google, Inc offers an array of products and services to all of its end-users. However their search capabilities are the foundation for Google’s current success and their primary business focus. Currently, Google offers over twenty different search applications that allow users to search the internet for books, maps, videos, images, products and much more. Their product decisions have allowed users demands to be met while focusing on the free based model. This allows users to access Google data free of charge and indirectly gives Google a strong competitive advantage of other competitors along with the accuracy of the search results. According to Google, Inc, they offer the following types of searching capabilities: Alerts Get email updates on the topics of your choice Blog Search Find blogs on your favorite topics  Books Search the full text of books  Custom Search Create a customized search experience for your community  Desktop Search and personalize your computer  Dictionary Search for definitions of words and phrases Directory Search the web, organized by topic or category Earth Explore the world from your computer Finance Business info, news and interactive charts GOOG-411 Find and connect for free with businesses from your phone  Images Search for images on the web Maps View maps and directions News Search thousands of news stories Patent Search Search the full text of US Patents Product Search Search for stuff to buy Scholar Search scholarly papers Toolbar Add a search box to your browser Trends Explore past and present search trends Videos Search for videos on the web Web Search Search billions of web pages Web Search Features Find movies, music, stocks, books and more mapping Google’s free based business model is only one way it differentiates itself from its competition. There is also a strong focus on the accuracy of search results and the speed in which they are returned to the end-user. Quality function deployment (QFD) is a structured method used to help connect user needs to the design features of a project proposed to address those needs. This method is particularly useful in accounting for needs that are not easily articulated or precisely defined according to the U. S. Department of Transportation Federal Highway Administration. Due to the fact that QFD is so customer driven Google is always in a constant state of change in attempt to reengineer its search algorithms, and other dependant systems so that end-users requirements are constantly being met. Value engineering is a key example of this, Google is constantly trying to improve all aspects of its products, improve system maintainability, and system interoperability. Bridgefield Group defines value engineering as an organized methodology that identifies and selects the lowest lifecycle cost options in design, materials and processes that achieves the desired level of performance, reliability and customer satisfaction. In addition, it seeks to remove unnecessary costs in the above areas and is often a joint effort with cross-functional internal teams and relevant suppliers. Common issues that appear when developing large scale systems like Google’s search applications include modular design of a product and/or service and providing accurate value analysis. A design approach that adheres to four fundamental tenets of cohesiveness, encapsulation, self-containment, and high binding to design a system component as an independently operable unit subject to change is how the Open System Joint Task Force defines modular design. More specifically M. S. Schmaltz defines modular software design as having a large collection of statements strung together in one partition of in-line code; we segment or divide the statements into logical groups called modules. Each module performs one or two tasks, and then passes control to another module. By breaking up the code into "bite-sized chunks", so to speak, we are able to better control the flow of data and control. This is especially true in large software systems. Value analysis is a process to evaluate products and services based on effectiveness, safety, and cost. Value analysis involves assessing the quality as well as the cost of a product or service as defined by the Healthcare Financial Management Association.  “Operations Management deals with the design and management of products, processes, services and supply chains. It considers the acquisition, development, and utilization of resources that firms need to deliver the goods and services their clients want.” (MIT,2010) Google, Inc encourages an open environment between all employees, also known as Googlers. This is reinforced by a cross-section team or cross-functional teams comprised from multiple departments assigned to every project so that every department like marketing, finance, and quality assurance has input on every project. In addition, Google is known for their openness to new ideas regardless of the status or seniority of an employee. In fact, Google allows for 20% of an employee’s time can be devoted to developing new ideas and/or pet projects. HumTech.com defines a cross-functional team as a collection of people with varied levels of skills and experience brought together to accomplish a task. As the name implies, Cross-Functional Team members come from different organizational units. Cross-Functional Teams may be permanent or ad hoc. Google’s search application product strategy primarily focuses on mass customization. This is allows Google to create a base search application and allows results to be returned to the end-users quickly based on specific parameters and search settings. In addition, they also store the data that is returned in case other desire the same results based on other end-users supplying the same customized settings. This allows Google to appear to render search results in virtually real-time to the user while allowing for complete customization of the searching criteria. Greg Vogl, a professor at Uganda Martyrs University, defines mass customization as when a business gives its customers the opportunity to tailor its products or services to the customer's specifications. The IT staff at Google play a key role in ensuring that the search application’s product strategy is maintained simply because the IT staff designs, develops, and maintains all of their proprietary applications. In fact, they also maintain all network infrastructure to ensure that it is available to all end-users. References: http://www.google.com/intl/en/options/ http://ops.fhwa.dot.gov/freight/publications/ftat_user_guide/sec5.htm http://www.bridgefieldgroup.com/bridgefieldgroup/glos9.htm#V http://www.acq.osd.mil/osjtf/termsdef.html http://www.cise.ufl.edu/~mssz/Pascal-CGS2462/prog-dsn.html http://www.hfma.org/publications/business_caring_newsletter/exclusives/Supply+and+Inventory+Terms+Defined.htm http://mitsloan.mit.edu/omg/om-definition.php http://www.humtech.com/opm/grtl/ols/ols3.cfm http://www.gregvogl.net/courses/mis1/glossary.htm

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  • Hack Extension Files to Make Them Version-Compatible for Firefox

    - by Asian Angel
    A well known drawback in using Firefox is the problem with extension compatibility when a new major version is released. Whether it is for a new extension that you are trying for the first time or an old favorite we have a way to get those extensions working for you again. There are multiple reasons why you might want to choose this method to fix a non-compatible extension: You are uncomfortable with tweaking the “about:config” settings You prefer to maintain the original “about:config” settings in a pristine state and like having compatibility checking active You are looking to gain some “geek cred” Keep in mind that most extensions will work perfectly well with a new version of Firefox and simply have the “version compatibility number” problem. But once in a while there may be one that needs to have some work done on it by the extension’s author. The Problem Here is a perfect example of everyone’s least favorite “extension message”. This is the last thing that you need when all that you want is for your favorite extension (or a new one) to work on a fresh clean install. Note: This works nicely to “replace” non-compatible extensions already present in your browser if you are simply upgrading. Hacking the XPI File For this procedure you will need to manually download the extension to your hard-drive (right click on the extension’s “Install Button” and select “Save As”). Once you have done that you are ready to start hacking the extension. For our example we chose the “GCal Popup Extension”. The best thing to do is place the extension in a new folder (i.e. the Desktop or other convenient location) then unzip it just the same way that you would with any regular zip file. Once it is unzipped you will see the various folders and files that were in the “xpi file” (we had four files here but depending on the extension the number may vary). There is only one file that you need to focus on…the “install.rdf” file. Note: At this point you should move the original extension file to a different location (i.e. outside of the folder) so that it is no longer present. Open the file in “Notepad” so that you can change the number for the “maxVersion”. Here the number is listed as “3.5.*” but we needed to make it higher… Replacing the “5” with a “7” is all that we needed to do. Once you have entered your new “maxVersion” number save the file. At this point you will need to re-zip all of the files back into a single file. Make certain that you “create” a file with the “.zip file extension” otherwise this will not work. Once you have the new zip file created you will need to rename the entire file including the “file extension”. For our example we copied and pasted the original extension name. Once you have changed the name click outside of the “text area”. You will see a small message window like this asking for confirmation…click “Yes” to finish the process. Now your modified/updated extension is ready to install. Drag the extension into your browser to install it and watch that wonderful “Restart to complete the installation.” message appear. As soon as your browser starts you can check the “Add-ons Manager Window” and see the version compatibility numbers for the extension. Looking very very nice! And just like that your extension should be up and running without any problems. Conclusion If you are looking to try something new, gain some geek cred, or just want to keep your Firefox install as close to the original condition as possible this method should get those extensions working nicely for you again. Similar Articles Productive Geek Tips Make Firefox Extensions Compatible After Firefox Update Breaks Them For No Good ReasonCheck Extension Compatibility for Upcoming Firefox ReleasesFirefox 3.6 Release Candidate Available, Here’s How to Fix Your Incompatible ExtensionsHow To Force Extension Compatibility with Firefox 3.6+Test and Report Add-on Compatibility in Firefox TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional 15 Great Illustrations by Chow Hon Lam Easily Sync Files & Folders with Friends & Family Amazon Free Kindle for PC Download Stretch popurls.com with a Stylish Script (Firefox) OldTvShows.org – Find episodes of Hitchcock, Soaps, Game Shows and more Download Microsoft Office Help tab

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  • SQL SERVER – Step by Step Guide to Beginning Data Quality Services in SQL Server 2012 – Introduction to DQS

    - by pinaldave
    Data Quality Services is a very important concept of SQL Server. I have recently started to explore the same and I am really learning some good concepts. Here are two very important blog posts which one should go over before continuing this blog post. Installing Data Quality Services (DQS) on SQL Server 2012 Connecting Error to Data Quality Services (DQS) on SQL Server 2012 This article is introduction to Data Quality Services for beginners. We will be using an Excel file Click on the image to enlarge the it. In the first article we learned to install DQS. In this article we will see how we can learn about building Knowledge Base and using it to help us identify the quality of the data as well help correct the bad quality of the data. Here are the two very important steps we will be learning in this tutorial. Building a New Knowledge Base  Creating a New Data Quality Project Let us start the building the Knowledge Base. Click on New Knowledge Base. In our project we will be using the Excel as a knowledge base. Here is the Excel which we will be using. There are two columns. One is Colors and another is Shade. They are independent columns and not related to each other. The point which I am trying to show is that in Column A there are unique data and in Column B there are duplicate records. Clicking on New Knowledge Base will bring up the following screen. Enter the name of the new knowledge base. Clicking NEXT will bring up following screen where it will allow to select the EXCE file and it will also let users select the source column. I have selected Colors and Shade both as a source column. Creating a domain is very important. Here you can create a unique domain or domain which is compositely build from Colors and Shade. As this is the first example, I will create unique domain – for Colors I will create domain Colors and for Shade I will create domain Shade. Here is the screen which will demonstrate how the screen will look after creating domains. Clicking NEXT it will bring you to following screen where you can do the data discovery. Clicking on the START will start the processing of the source data provided. Pre-processed data will show various information related to the source data. In our case it shows that Colors column have unique data whereas Shade have non-unique data and unique data rows are only two. In the next screen you can actually add more rows as well see the frequency of the data as the values are listed unique. Clicking next will publish the knowledge base which is just created. Now the knowledge base is created. We will try to take any random data and attempt to do DQS implementation over it. I am using another excel sheet here for simplicity purpose. In reality you can easily use SQL Server table for the same. Click on New Data Quality Project to see start DQS Project. In the next screen it will ask which knowledge base to use. We will be using our Colors knowledge base which we have recently created. In the Colors knowledge base we had two columns – 1) Colors and 2) Shade. In our case we will be using both of the mappings here. User can select one or multiple column mapping over here. Now the most important phase of the complete project. Click on Start and it will make the cleaning process and shows various results. In our case there were two columns to be processed and it completed the task with necessary information. It demonstrated that in Colors columns it has not corrected any value by itself but in Shade value there is a suggestion it has. We can train the DQS to correct values but let us keep that subject for future blog posts. Now click next and keep the domain Colors selected left side. It will demonstrate that there are two incorrect columns which it needs to be corrected. Here is the place where once corrected value will be auto-corrected in future. I manually corrected the value here and clicked on Approve radio buttons. As soon as I click on Approve buttons the rows will be disappeared from this tab and will move to Corrected Tab. If I had rejected tab it would have moved the rows to Invalid tab as well. In this screen you can see how the corrected 2 rows are demonstrated. You can click on Correct tab and see previously validated 6 rows which passed the DQS process. Now let us click on the Shade domain on the left side of the screen. This domain shows very interesting details as there DQS system guessed the correct answer as Dark with the confidence level of 77%. It is quite a high confidence level and manual observation also demonstrate that Dark is the correct answer. I clicked on Approve and the row moved to corrected tab. On the next screen DQS shows the summary of all the activities. It also demonstrates how the correction of the quality of the data was performed. The user can explore their data to a SQL Server Table, CSV file or Excel. The user also has an option to either explore data and all the associated cleansing info or data only. I will select Data only for demonstration purpose. Clicking explore will generate the files. Let us open the generated file. It will look as following and it looks pretty complete and corrected. Well, we have successfully completed DQS Process. The process is indeed very easy. I suggest you try this out yourself and you will find it very easy to learn. In future we will go over advanced concepts. Are you using this feature on your production server? If yes, would you please leave a comment with your environment and business need. It will be indeed interesting to see where it is implemented. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Business Intelligence, Data Warehousing, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Data Quality Services, DQS

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  • Good ol fashioned debugging

    - by Tim Dexter
    I have been helping out one of our new customers over the last day or two and I have even managed to get to the bottom of their problem FTW! They use BIEE and BIP and wanted to mount a BIP report in a dashboard page, so far so good, BIP does that! Just follow the instructions in the BIEE user guide. The wrinkle is that they want to enter some fixed instruction strings into the dashboard prompts to help the user. These are added as fixed values to the prompt as the default values so they appear first. Once the user makes a selection, the default strings disappear. Its a fair requirement but the BIP report chokes Now, the BIP report had been setup with the Autorun checkbox, unchecked. I expected the BIP report to wait for the Go button to be hit but it was trying to run immediately and failing. That was the first issue. You can not stop the BIP report from trying to run in a dashboard. Even if the Autorun is turned off, it seems that dashboard still makes the request to BIP to run the report. Rather than BIP refusing because its waiting for input it goes ahead anyway, I guess the mechanism does not check the autorun flag when the request is coming from the dashboard. It appears that between BIEE and BIP, they collectively ignore the autorun flag. A bug? might be, at least an enhancement request. With that in mind, how could we get BIP to not at least not fail? This fact was stumping me on the parameter error, if the autorun flag was being respected then why was BIP complaining about the parameter values it should not even be doing anything until the Go button is clicked. I now knew that the autorun flag was being ignored, it was a simple case of putting BIP into debug mode. I use the OC4J server on my laptop so debug msgs are routed through the dos box used to start the OC4J container. When I changed a value on the dashboard prompt I spotted some debug text rushing by that subsequently disappeared from the log once the operation was complete. Another bug? I needed to catch that text as it went by, using the print screen function with some software to grab multiple screens as the log appeared and then disappeared. The upshot is that when you change the dashboard prompt value, BIP validates the value against its own LOVs, if its not in the list then it throws the error. Because 'Fill this first' and 'Fill this second' ie fixed strings from the dashboard prompts, are not in the LOV lists and because the report is auto running as soon as the dashboard page is brought up, the report complains about invalid parameters. To get around this, I needed to get the strings into the LOVs. Easily done with a UNION clause: select 'Fill this first' from SH.Products Products UNION select Products."Prod Category" as "Prod Category" from SH.Products Products Now when BIP wants to validate the prompt value, the LOV query fires and finds the fixed string -> No Error. No data, but definitely no errors :0) If users do run with the fixed values, you can capture that in the template. If there is no data in the report, either the fixed values were used or the parameters selected resulted in no rows. You can capture this in the template and display something like. 'Either your parameter values resulted in no data or you have not changed the default values' Thats the upside, the downside is that if your users run the report in the BP UI they re going to see the fixed strings. You could alleviate that by having BIP display the fixed strings in top of its parameter drop boxes (just set them as the default value for the parameter.) But they will not disappear like they do in the dashboard prompts, see below. If the expected autorun behaviour worked ie wait for the Go button, then we would not have to workaround it but for now, its a pretty good solution. It was an enjoyable hour or so for me, took me back to my developer daze, when we used to race each other for the most number of bug fixes. I used to run a distant 2nd behind 'Bugmeister Chen Hu' but led the chasing pack by a reasonable distance.

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  • Robotic Arm &ndash; Hardware

    - by Szymon Kobalczyk
    This is first in series of articles about project I've been building  in my spare time since last Summer. Actually it all began when I was researching a topic of modeling human motion kinematics in order to create gesture recognition library for Kinect. This ties heavily into motion theory of robotic manipulators so I also glanced at some designs of robotic arms. Somehow I stumbled upon this cool looking open source robotic arm: It was featured on Thingiverse and published by user jjshortcut (Jan-Jaap). Since for some time I got hooked on toying with microcontrollers, robots and other electronics, I decided to give it a try and build it myself. In this post I will describe the hardware build of the arm and in later posts I will be writing about the software to control it. Another reason to build the arm myself was the cost factor. Even small commercial robotic arms are quite expensive – products from Lynxmotion and Dagu look great but both cost around USD $300 (actually there is one cheap arm available but it looks more like a toy to me). In comparison this design is quite cheap. It uses seven hobby grade servos and even the cheapest ones should work fine. The structure is build from a set of laser cut parts connected with few metal spacers (15mm and 47mm) and lots of M3 screws. Other than that you’d only need a microcontroller board to drive the servos. So in total it comes a lot cheaper to build it yourself than buy an of the shelf robotic arm. Oh, and if you don’t like this one there are few more robotic arm projects at Thingiverse (including one by oomlout). Laser cut parts Some time ago I’ve build another robot using laser cut parts so I knew the process already. You can grab the design files in both DXF and EPS format from Thingiverse, and there are also 3D models of each part in STL. Actually the design is split into a second project for the mini servo gripper (there is also a standard servo version available but it won’t fit this arm).  I wanted to make some small adjustments, layout, and add measurements to the parts before sending it for cutting. I’ve looked at some free 2D CAD programs, and finally did all this work using QCad 3 Beta with worked great for me (I also tried LibreCAD but it didn’t work that well). All parts are cut from 4 mm thick material. Because I was worried that acrylic is too fragile and might break, I also ordered another set cut from plywood. In the end I build it from plywood because it was easier to glue (I was told acrylic requires a special glue). Btw. I found a great laser cutter service in Kraków and highly recommend it (www.ebbox.com.pl). It cost me only USD $26 for both sets ($16 acrylic + $10 plywood). Metal parts I bought all the M3 screws and nuts at local hardware store. Make sure to look for nylon lock (nyloc) nuts for the gripper because otherwise it unscrews and comes apart quickly. I couldn’t find local store with metal spacers and had to order them online (you’d need 11 x 47mm and 3 x 15mm). I think I paid less than USD $10 for all metal parts. Servos This arm uses five standards size servos to drive the arm itself, and two micro servos are used on the gripper. Author of the project used Modelcraft RS-2 Servo and Modelcraft ES-05 HT Servo. I had two Futaba S3001 servos laying around, and ordered additional TowerPro SG-5010 standard size servos and TowerPro SG90 micro servos. However it turned out that the SG90 won’t fit in the gripper so I had to replace it with a slightly smaller E-Sky EK2-0508 micro servo. Later it also turned out that Futaba servos make some strange noise while working so I swapped one with TowerPro SG-5010 which has higher torque (8kg / cm). I’ve also bought three servo extension cables. All servos cost me USD $45. Assembly The build process is not difficult but you need to think carefully about order of assembling it. You can do the base and upper arm first. Because two servos in the base are close together you need to put first with one piece of lower arm already connected before you put the second servo. Then you connect the upper arm and finally put the second piece of lower arm to hold it together. Gripper and base require some gluing so think it through too. Make sure to look closely at all the photos on Thingiverse (also other people copies) and read additional posts on jjshortcust’s blog: My mini servo grippers and completed robotic arm  Multiply the robotic arm and electronics Here is also Rob’s copy cut from aluminum My assembled arm looks like this – I think it turned out really nice: Servo controller board The last piece of hardware I needed was an electronic board that would take command from PC and drive all seven servos. I could probably use Arduino for this task, and in fact there are several Arduino servo shields available (for example from Adafruit or Renbotics).  However one problem is that most support only up to six servos, and second that their accuracy is limited by Arduino’s timer frequency. So instead I looked for dedicated servo controller and found a series of Maestro boards from Pololu. I picked the Pololu Mini Maestro 12-Channel USB Servo Controller. It has many nice features including native USB connection, high resolution pulses (0.25µs) with no jitter, built-in speed and acceleration control, and even scripting capability. Another cool feature is that besides servo control, each channel can be configured as either general input or output. So far I’m using seven channels so I still have five available to connect some sensors (for example distance sensor mounted on gripper might be useful). And last but important factor was that they have SDK in .NET – what more I could wish for! The board itself is very small – half of the size of Tic-Tac box. I picked one for about USD $35 in this store. Perhaps another good alternative would be the Phidgets Advanced Servo 8-Motor – but it is significantly more expensive at USD $87.30. The Maestro Controller Driver and Software package includes Maestro Control Center program with lets you immediately configure the board. For each servo I first figured out their move range and set the min/max limits. I played with setting the speed an acceleration values as well. Big issue for me was that there are two servos that control position of lower arm (shoulder joint), and both have to be moved at the same time. This is where the scripting feature of Pololu board turned out very helpful. I wrote a script that synchronizes position of second servo with first one – so now I only need to move one servo and other will follow automatically. This turned out tricky because I couldn’t find simple offset mapping of the move range for each servo – I had to divide it into several sub-ranges and map each individually. The scripting language is bit assembler-like but gets the job done. And there is even a runtime debugging and stack view available. Altogether I’m very happy with the Pololu Mini Maestro Servo Controller, and with this final piece I completed the build and was able to move my arm from the Meastro Control program.   The total cost of my robotic arm was: $10 laser cut parts $10 metal parts $45 servos $35 servo controller ----------------------- $100 total So here you have all the information about the hardware. In next post I’ll start talking about the software that I wrote in Microsoft Robotics Developer Studio 4. Stay tuned!

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  • Formal Languages, Inductive Proofs &amp; Regular Expressions

    - by MarkPearl
    So I am slogging away at my UNISA stuff. I have just finished doing the initial once non stop read through the first 11 chapters of my COS 201 Textbook - “Introduction to Computer Theory 2nd Edition” by Daniel Cohen. It has been an interesting couple of days, with familiar concepts coming up as well as some new territory. In this posting I am going to cover the first couple of chapters of the book. Let start with Formal Languages… What exactly is a formal language? Pretty much a no duh question for me but still a good one to ask – a formal language is a language that is defined in a precise mathematical way. Does that mean that the English language is a formal language? I would say no – and my main motivation for this is that one can have an English sentence that is correct grammatically that is also ambiguous. For example the ambiguous sentence: "I once shot an elephant in my pyjamas.” For this and possibly many other reasons that I am unaware of, English is termed a “Natural Language”. So why the importance of formal languages in computer science? Again a no duh question in my mind… If we want computers to be effective and useful tools then we need them to be able to evaluate a series of commands in some form of language that when interpreted by the device no confusion will exist as to what we were requesting. Imagine the mayhem that would exist if a computer misinterpreted a command to print a document and instead decided to delete it. So what is a Formal Language made up of… For my study purposes a language is made up of a finite alphabet. For a formal language to exist there needs to be a specification on the language that will describe whether a string of characters has membership in the language or not. There are two basic ways to do this: By a “machine” that will recognize strings of the language (e.g. Finite Automata). By a rule that describes how strings of a language can be formed (e.g. Regular Expressions). When we use the phrase “string of characters”, we can also be referring to a “word”. What is an Inductive Proof? So I am not to far into my textbook and of course it starts referring to proofs and different types. I have had to go through several different approaches of proofs in the past, but I can never remember their formal names , so when I saw “inductive proof” I thought to myself – what the heck is that? Google to the rescue… An inductive proof is like a normal proof but it employs a neat trick which allows you to prove a statement about an arbitrary number n by first proving it is true when n is 1 and then assuming it is true for n=k and showing it is true for n=k+1. The idea is that if you want to show that someone can climb to the nth floor of a fire escape, you need only show that you can climb the ladder up to the fire escape (n=1) and then show that you know how to climb the stairs from any level of the fire escape (n=k) to the next level (n=k+1). Does this sound like a form of recursion? No surprise then that in the same chapter they deal with recursive definitions. An example of a recursive definition for the language EVEN would the 3 rules below: 2 is in EVEN If x is in EVEN then so is x+2 The only elements in the set EVEN are those that be produced by the rules above. Nothing to exciting… So if a definition for a language is done recursively, then it makes sense that the language can be proved using induction. Regular Expressions So I am wondering to myself what use is this all – in fact – I find this the biggest challenge to any university material is that it is quite hard to find the immediate practical applications of some theory in real life stuff. How great was my joy when I suddenly saw the word regular expression being introduced. I had been introduced to regular expressions on Stack Overflow where I was trying to recognize if some text measurement put in by a user was in a valid form or not. For instance, the imperial system of measurement where you have feet and inches can be represented in so many different ways. I had eventually turned to regular expressions as an easy way to check if my parser could correctly parse the text or not and convert it to a normalize measurement. So some rules about languages and regular expressions… Any finite language can be represented by at least one if not more regular expressions A regular expressions is almost a rule syntax for expressing how regular languages can be formed regular expressions are cool For a regular expression to be valid for a language it must be able to generate all the words in the language and no other words. This is important. It doesn’t help me if my regular expression parses 100% of my measurement texts but also lets one or two invalid texts to pass as well. Okay, so this posting jumps around a bit – but introduces some very basic fundamentals for the subject which will be built on in later postings… Time to go and do some practical examples now…

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  • Customize Team Build 2010 – Part 16: Specify the relative reference path

    In the series the following parts have been published Part 1: Introduction Part 2: Add arguments and variables Part 3: Use more complex arguments Part 4: Create your own activity Part 5: Increase AssemblyVersion Part 6: Use custom type for an argument Part 7: How is the custom assembly found Part 8: Send information to the build log Part 9: Impersonate activities (run under other credentials) Part 10: Include Version Number in the Build Number Part 11: Speed up opening my build process template Part 12: How to debug my custom activities Part 13: Get control over the Build Output Part 14: Execute a PowerShell script Part 15: Fail a build based on the exit code of a console application Part 16: Specify the relative reference path As I have already blogged about, it is not intuitive how to specify the paths where the build server has to look for references that are stored in Source Control. It is a common practice to store 3rd party libraries in Source Control, so they are available to everyone, everyone uses the same version of the libraries and updating a library can be done centrally. In Team Build 2010 these paths are specified as a parameter for MSBuild. What we will do in this post is building the values for this parameter based on the values in an argument. You are now pretty aware how to customize the build template, so let’s do the modifications in another way. Instead of opening the xaml file in the workflow designer, we open it in the XML editor. You can open it in the XML Editor by either selecting the Open with menu (see the context menu), or by choosing the View code option. To add this functionality we need to: Specify a new argument Add the argument to the metadata Build the absolute paths for the references and add these paths to the MSBuild arguments 1. Specify a new argument Locate at the top of the document the Members (which are the arguments) of the XAML and add the following line <x:Property Name="ReferencePaths" Type="InArgument(s:String[])" /> 2. Add the argument to the metadata Then locate the line <mtbw:ProcessParameterMetadataCollection> and paste the following line <mtbw:ProcessParameterMetadata Category="Misc" Description="The list of reference paths, relative to the root path in the Workspace mapping." DisplayName="Reference paths" ParameterName="ReferencePaths" /> 3. Build the absolute paths for the references and add these paths to the MSBuild arguments Now locate the place where the assignments are done to the variables used in the agent. And add the following lines after the last Assign activity         <Sequence DisplayName="Initialize ReferencePath" sap:VirtualizedContainerService.HintSize="464,428">           <Sequence.Variables>             <Variable x:TypeArguments="x:String" Name="ReferencePathsArgument">               <Variable.Default>                 <Literal x:TypeArguments="x:String" Value="" />               </Variable.Default>             </Variable>           </Sequence.Variables>           <sap:WorkflowViewStateService.ViewState>             <scg:Dictionary x:TypeArguments="x:String, x:Object">               <x:Boolean x:Key="IsExpanded">True</x:Boolean>             </scg:Dictionary>           </sap:WorkflowViewStateService.ViewState>           <ForEach x:TypeArguments="x:String" DisplayName="Iterate through the paths" sap:VirtualizedContainerService.HintSize="287,206" mtbwt:BuildTrackingParticipant.Importance="Low" Values="[ReferencePaths]">             <ActivityAction x:TypeArguments="x:String">               <ActivityAction.Argument>                 <DelegateInArgument x:TypeArguments="x:String" Name="path" />               </ActivityAction.Argument>               <Assign x:TypeArguments="x:String" DisplayName="Build ReferencePath argument" sap:VirtualizedContainerService.HintSize="257,100" mtbwt:BuildTrackingParticipant.Importance="Low"  To="[ReferencePathsArgument]" Value="[If(String.IsNullOrEmpty(ReferencePathsArgument), &quot;&quot;, ReferencePathsArgument + &quot;;&quot;) + IO.Path.Combine(SourcesDirectory, path)]" />             </ActivityAction>           </ForEach>           <Assign DisplayName="Append the reference paths to the MSBuild Arguments" sap:VirtualizedContainerService.HintSize="287,58">             <Assign.To>               <OutArgument x:TypeArguments="x:String">[MSBuildArguments]</OutArgument>             </Assign.To>             <Assign.Value>               <InArgument x:TypeArguments="x:String">[String.Format("{0} /p:ReferencePath=""{1}""", MSBuildArguments, ReferencePathsArgument)]</InArgument>             </Assign.Value>           </Assign>         </Sequence> Now you can use the template to specify the paths relative to SourcesDirectory. You can download the full solution at BuildProcess.zip. It will include the sources of every part and will continue to evolve.

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  • Initial Review - Mastering Unreal Technology I: Introduction to Level Design with Unreal Engine 3

    - by Matt Christian
    Recently I purchased 3 large volumes on using the Unreal 3 Engine to create levels and custom games.  This past weekend I cracked the spine of the first and started reading.  Here are my early impressions (I'm ~250 pages into it, with appendices it's about 900). Pros Interestingly, the book starts with an overview of the Unreal engines leading up to Unreal 3 (including Gears of War) and follows with some discussion on planning a mod and what goes into the game development process.  This is nice for an intro to the book and is much preferred rather than a simple chapter detailing what is on the included CD, how to install and setup UnrealEd, etc...  While the chapter on Unreal history and planning can be considered 'fluff', it's much less 'fluffy' than most books provide. I need to mention one thing here that is pretty crucial in the way I'm going to continue reviewing this book.  Most technical books like this are used as a shelf reference; as a thick volume you use for looking up techniques every now and again.  Even so, I prefer reading from cover to cover, including chapters I may already be knowledgable on (I'm sure this is typical for most people).  If there was a chapter on installing UnrealEd (the previously mentioned 'fluff'), I would probably force myself to read it, even though I've installed the game and engine multiple times on different systems. Chapter 3 is where we really get to the introduction piece of UnrealEd, creating your first basic level.  This large chapter details creating two small rooms, adding static meshes, adding lighting, creating and adding particle emitters, creating a door that animates with Unreal Matinee and Kismet, static meshes with physics, and other little additions to make your level look less beginner.  This really is a chapter that overviews the entire rest of the book, as each chapter following details the creation and intermediate usages of Static Meshes, Materials, Lighting, etc... One other very nice part to this book is the way the tutorials are setup.  Each tutorial builds off the previous and all are step-by-step.  If you haven't completed one yet, you can find all the starting files on the CD that comes with the book. Cons While the description of the overview chapter (Chapter 3) is fresh in your mind, let me start the cons by saying this chapter is setup extremely confusing for the noob.  At one point, you end up creating a door mesh and setting it up as a InteropMesh so that it is ready to be animated, only to switch to particles and spend a good portion of time working on a different piece of the level.  Yes, this is actually how I develop my levels (jumping back and forth), though it's very odd for a book to jump out of sequence. The next item might be a positive or a negative depending on your skill level with UnrealEd.  Most of the introduction to the editor layout is found in one of the Appendices instead of before Chapter 3.  For new readers, this might lead to confusion as Appendix A would typically be read between Chapter 2 and 3.  However, this is a positive for those with some experience in UnrealEd as they don't have to force themselves through a 'learn every editor button' chapter.  I'm listing this in the Cons section as the book is 'Introduction to...' and is probably going to be directed toward a lot of very beginner developers. Finally, there's a lack of general description to a lot of the underlying engine and what each piece in UnrealEd is or does.  Sometimes you'll be performing Tutorial after Tutorial with barely a paragraph in between describing ANY of what you've just done.  Tutorial 1.1 Step 6 says to press Button X, so you do.  But why?  This is in part a problem with the structure of the tutorials rather than the content of the book.  Since the tutorials are so focused on a step-by-step (or procedural) description of a process, you learn the process and not why you're doing that.  For example, you might learn how to size a material to a surface, but will only learn what buttons to press and not what each one does. This becomes extremely apparent in the chapter on Static Meshes as most of the chapter is spent in 3D Studio Max.  Since there are books on 3DSM and modelling, the book really only tells you the steps and says to go grab a book on modelling if you're really interested in 3DSM.  Again, I've learned the process to develop my own meshes in 3DSM, but I don't know the why behind the steps. Conclusion So far the book is very good though I would have a hard time recommending it to a complete beginner.  I would suggest anyone looking at this book (obviously including the other 2, more advanced volumes) to pick up a copy of UDK or Unreal 3 (available online or via download services such as Steam) and watch some online tutorials and play with it first.  You'll find plenty of online videos available that were created by the authors and may suit as a better introduction to the editor.

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  • Oracle Enterprise Manager 12c Integration With Oracle Enterprise Manager Ops Center 11g

    - by Scott Elvington
    In a blog entry earlier this year, we announced the availability of the Ops Center 11g plug-in for Enterprise Manager 12c. In this article I will walk you through the process of deploying the plug-in on your existing Enterprise Manager agents and show you some of the capabilities the plug-in provides. We'll also look at the integration from the Ops Center perspective. I will show you how to set up the connection to Enterprise Manager and give an overview of the information that is available. Installing and Configuring the Ops Center Plug-in The plug-in is available for download from the Self Update page (Setup ? Extensibility ? Self Update). The plug-in name is “Ops Center Infrastructure stack”. Once you have downloaded the plug-in you can navigate to the Plug-In management page (Setup ? Extensibility ? Plug-ins) to begin deployment. The plug-in must first be deployed on the Management Server. You will need to provide the repository password of the SYS user in order to deploy the plug-in to the Management Server. There are a few pre-requisites that need to be completed on the Ops Center side before the plug-in can be deployed and configured on the desired Enterprise Manager agents. Any servers, whether physical or virtual, for which you wish to see metrics and alerts need to be managed by Ops Center. This means that the Operating System needs to have an Ops Center management agent installed as a minimum. The plug-in can provide even more value when Ops Center is also managing the other “layers of the stack”, for example the service processor, the blade chassis or the XSCF of an M-Series server. The more information that Ops Center has about the stack, the more information that will be visible within Enterprise Manager via the plug-in. In order to access the information within Ops Center, the plug-in requires a user to connect as. This user does not require any particular Ops Center permissions or roles, it simply needs to exist. You can create a specific “EMPlugin” user within Ops Center or use an existing user. Oracle recommends creating a specific, non-privileged user account within Ops Center for this purpose. From the Ops Center Administration section, select Enterprise Controller, click the Users tab and finally click the Add User icon to create the desired user account. For the purpose of this article I have discovered and managed the OS and service processor of the server where my Enterprise Manager 12c installation is hosted. With the plug-in deployed to the Management Server and the setup done within Ops Center, we're now ready to deploy the plug-in to the agents and configure the targets to communicate with the Ops Center Enterprise Controller. From the Setup menu select Add Targets then Add Targets Manually. Select the bottom radio button “Add Targets Manually by Specifying Target Monitoring Properties”, select Infrastructure Stack from the Target Type dropdown and finally, select the Monitoring Agent where you wish to deploy the plug-in. Click the Add Manually.... button and fill in the details for the new target using the appropriate hostname for your Enterprise Controller and the user and password details for the plug-in access user. After the target has been added to the agent you will need to allow a few minutes for the initial data collection to complete. Once completed you can see the new target in the All Targets list. All metric collections are enabled by default except one. To enable Infrastructure Stack Alarms collection, navigate to the newly added target and then to Target ? Monitoring ? Metric and Collection Settings. There you can click the “Disabled” link under Collection Schedule to enable collection and set your desired collection frequency. By default, a Warning level alert in Ops Center will equate to a Warning level event in Enterprise Manager and a Critical alert will equate to a Critical event. This mapping can be altered in the Metric and Collection Settings also. The default incident rules in Enterprise Manager only create incidents from Critical events so keep this in mind in case you want to see incidents generated for Warning or Info level alerts from Ops Center. Also, because Enterprise Manager already monitors the OS through it's Host target type, the plug-in does not pull OS alerts from Ops Center so as to prevent duplication. In addition to alert propagation, the plug-in also provides data for several reports detailing the topology and configuration of the stack as well as any hardware sensor data that is available. These are available from the Information Publisher Reports. Navigate there from the Enterprise ? Reports menu or directly from the Infrastructure Stack target of interest. As an example, here is a sample of the Hardware Sensors report showing some of the available sensor data. The report can also be exported to a CSV file format if desired. Connecting Ops Center to Enterprise Manager Repository For an Enterprise Manager user, the plug-in provides a deeper visibility to the state of the infrastructure underlying the databases and middleware. On the Ops Center side, there is also a greater visibility to the targets running on the infrastructure. To set up the Ops Center data collection, just navigate to the Administration section and select the Grid Control link. Select the Configure/Connect action from the right-hand menu and complete the wizard forms to enable the connection to the Enterprise Manager repository and UI. Be sure to use the sysman account when configuring the database connection. Once the job completes and the initial data synchronization is done you will see new Target tabs on your OS assets. The new tab lists all the Enterprise Manager targets and any alerts, availability and performance data specific to the selected target. It is also possible to use the GoTo icon to launch the Enterprise Manager BUI in context of the specific target or alert to drill into more detail. Hopefully this brief overview of the integration between Enterprise Manager and Ops Center has provided a jumpstart to getting a more complete view of the full stack of your enterprise systems.

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  • CodePlex Daily Summary for Saturday, May 15, 2010

    CodePlex Daily Summary for Saturday, May 15, 2010New ProjectsBizTalk EDI Guidance: BizTalk EDI Guidance is intended to simplify the delivery of EDI solutions by leveraging the ESB Toolkit. This project is currently Alpha and sh...Continues Integration Sample: I'm providing a series of blog post to show a complete CI process using CruiseControl.Net and msbuild. The source code for this series is hosted here.DioM2D: My Dragons in our Midst RPG. Runs on my custom Starlight Engine.Ethical Hacking ASP.NET: Security tools and guidelines for white-hat hacking and protecting ASP.NET web applications.Farseer Engine with XNATouch: Farseer is great engine for game physics. This implementation uses XNATouch framework.Feature Builder Guidance Extensions: Feature Builder Guidance Extensions are Feature Extensions which extend the guidance for the Feature Building experience. Each FBGX will be suppli...Microsoft Office Document Security: MODS is a plugin for office 2007 thats includes Hash Encryption, Hex Convertion and more. Plugins: MODS For Word still working on (MODS for Excel ...Minimize Engine (XNA): The Minimize Engine is a basic 3D Games Engine created using XNA, with its primary focus around Grid Based games.MSForge TownCrier: This project is meant to build a notification and calling system for MSForge.net User Groups.NatureProtector: Silverlight 4 project.OutSync: OutSync is a free Windows desktop application that syncs photos of your Facebook friends with matching contacts in Microsoft Outlook. It allows you...Quick Save Images, Clipboard save to file, Quick save, bmp, png, jpeg, Image: ClipSa is a very small tool for very quick picture saving. You put some picture into the clipboard (PrintScrn/Alt-PrintScrn/Ctrl-C), ClipSa saves ...ResHelper Manager: Resource strings management tool that creates localization files for any type of localization target (asp.net, wpf and so on...)SecureCookieHttpModule: Secure your session cookie (and other session-based) cookies for replay attacks using this easy to use ASP.NET HttpModule.simpleChMS: A Church Management System (ChMS) designed for churches or ministries like youth groups that want to facilitate better care or theie membership. Fo...sMAPtool: -SPDomainObject: mapping strong type objects to sp listsSQL Trim: This project aims at developing a universal trim function for Microsoft SQL Server. It trims: 1) pre spaces 2) post spaces 3) double spaces 3) subs...TurretGunner: mt-experienceNew ReleasesBeanProxy: BeanProxy 3.0: BeanProxy is a C# (.NET 3.5) library housing classes that facilitates unit testing. Any non-static, public interface/class or abstract class can be...Blueset Studio Opensource Projects: 蓝色之风记事本 0.2 Alpha: 一个超级Bug版本……CSharp Intellisense: V2.1: - Bug fix (Pascal Casing)DioM2D: DioM2D0.01: http://www.dragonsinourmidst.com/forums/showthread.php?p=690058#post690058Ethical Hacking ASP.NET: Version 1.0.0.1: This is the initial release of the project. Read more about the available tests and features on the Documentation tab. You need the full .NET Frame...Event Scavenger: Collector service update - version 3.2.4: Added check if the database connection string is set up in the config file.Feature Builder Guidance Extensions: FBGX-Binaries: This release consists of a zip file containing all the VSIXs resulting from building each of the FBGX packages found here as source. This will mak...Floe IRC Client: Floe IRC Client 2010-05 R2: - Detaching windows (right click on the tabs to detach them) - Highlight lines with your nick or other patterns - Fixed several bugs - Tabs can now...Free language translator and file converter: Free Language Translator 1.96: Fixed some minor bugs and improved the UI a bit. If you can not install the msi file you might be missing some prerequisites. You can try running t...Geocache Downloader: release 1.0: This is the first release.kp.net: Alpha release is avalable: The goal of this alpha release is to try the code in some production scenarios and find out what features should be tuned.Live-Exchange Calendar Sync: Live-Exchange Calendar Sync: Live-Exchange Calendar Sync Beta May 14, 2010 release of Live-Exchange Calendar Sync 1.0 BETA. (Version 45334) Getting StartedInfo about installat...MAPILab Explorer for SharePoint: MAPILab Explorer for SharePoint ver 2.1.1: 1) Small bug fixed that appears on first start (when earliers versions wasn't installed). How to install:Download ZIP file and extract it on Sha...Microsoft Office Document Security: MODS 4 WORD (SOURCE INCLUDED): Includes Source CodeMoonyDesk (windows desktop widgets): MoonyDesk Alpha: MoonyDesk Alpha (some memory improvements)OnTopReplica: Release 2.9.3: Some bugfixes and improvements. Czech translation added (thanks René Mihula).OutSync: OutSync v1.0.100.0: OutSync v1.0.100.0 is the final release by Mel before the move to CodePlex. I have tested it on Windows 7 32bit and 64bit with Office 2007 and it ...Quick Save Images, Clipboard save to file, Quick save, bmp, png, jpeg, Image: Clipsa v 0.1: Download and extract to any place 2 files - clipSa.exe and clipSa.exe.config Run clipSa.exe. That's all.ResHelper Manager: ResHelperManager: List of changes applied to this version of ResHelper is included in main download zip package. Example sourcesIn Source Code tab are sources of De...Rx Contrib: V1.3: - Bug Fix - BufferWithTimeOrCount with flexible time period setting when ever the time period elapsed...SharePoint DVK Integration: SharePoint 2007 DVK integration v1.0.3: Fixes Fixed default field bindings. I rebound too many fields on every page load. Fixed extension replacing on creating target url (threw it out)...ShoutcastStast for DotNetNuke: DNN_ShoutcastStats alpha 05.00.495: First Alpha release of ShoutcastStats Module for DotNetNuke This first alpha version of the ShoutcastStats Module for DotNetNuke is still in devel...SilverPart 2.1: SilverPart 2.1: SilverPart 2.1 This interim release fixes some major bugs related to Firefox and anonymous access. - Fix for Issue ID 4005 - SilverPart does not w...sMAPtool: sMAPedit v0.7c (Base Release with Maps): Fixed: force a gargabe collection update to prevent pictureBox's memory leak Added: essential map pack with all basic maps in jpg format Added:...SQL Trim: Trim: Initial releaseSSIS Multiple Hash: Multiple Hash V1.2.1: This is version 1.2.1 of the Multiple Hash SSIS Component. It supports SQL 2005 and SQL 2008, although you have to download the correct install pa...StreamInsight Yahoo Finance input adapter example: StockTicker_v1_0_RTM: Updated for StreamInsight RTM.Update Controls .NET: 2.1.0.0: Automatic dependency management for WPF and Silverlight data binding. This release combines both the WPF and Silverlight assemblies into one insta...VCC: Latest build, v2.1.30514.0: Automatic drop of latest buildMost Popular ProjectsRawrWBFS ManagerAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)patterns & practices – Enterprise LibraryMicrosoft SQL Server Community & SamplesPHPExcelASP.NETMost Active Projectspatterns & practices – Enterprise LibraryMirror Testing SystemRawrPHPExcelBlogEngine.NETMicrosoft Biology FoundationCustomer Portal Accelerator for Microsoft Dynamics CRMWindows Azure Command-line Tools for PHP DevelopersShake - C# MakeStyleCop

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  • An Alphabet of Eponymous Aphorisms, Programming Paradigms, Software Sayings, Annoying Alliteration

    - by Brian Schroer
    Malcolm Anderson blogged about “Einstein’s Razor” yesterday, which reminded me of my favorite software development “law”, the name of which I can never remember. It took much Wikipedia-ing to find it (Hofstadter’s Law – see below), but along the way I compiled the following list: Amara’s Law: We tend to overestimate the effect of a technology in the short run and underestimate the effect in the long run. Brook’s Law: Adding manpower to a late software project makes it later. Clarke’s Third Law: Any sufficiently advanced technology is indistinguishable from magic. Law of Demeter: Each unit should only talk to its friends; don't talk to strangers. Einstein’s Razor: “Make things as simple as possible, but not simpler” is the popular paraphrase, but what he actually said was “It can scarcely be denied that the supreme goal of all theory is to make the irreducible basic elements as simple and as few as possible without having to surrender the adequate representation of a single datum of experience”, an overly complicated quote which is an obvious violation of Einstein’s Razor. (You can tell by looking at a picture of Einstein that the dude was hardly an expert on razors or other grooming apparati.) Finagle's Law of Dynamic Negatives: Anything that can go wrong, will—at the worst possible moment. - O'Toole's Corollary: The perversity of the Universe tends towards a maximum. Greenspun's Tenth Rule: Any sufficiently complicated C or Fortran program contains an ad hoc, informally-specified, bug-ridden, slow implementation of half of Common Lisp. (Morris’s Corollary: “…including Common Lisp”) Hofstadter's Law: It always takes longer than you expect, even when you take into account Hofstadter's Law. Issawi’s Omelet Analogy: One cannot make an omelet without breaking eggs - but it is amazing how many eggs one can break without making a decent omelet. Jackson’s Rules of Optimization: Rule 1: Don't do it. Rule 2 (for experts only): Don't do it yet. Kaner’s Caveat: A program which perfectly meets a lousy specification is a lousy program. Liskov Substitution Principle (paraphrased): Functions that use pointers or references to base classes must be able to use objects of derived classes without knowing it Mason’s Maxim: Since human beings themselves are not fully debugged yet, there will be bugs in your code no matter what you do. Nils-Peter Nelson’s Nil I/O Rule: The fastest I/O is no I/O.    Occam's Razor: The simplest explanation is usually the correct one. Parkinson’s Law: Work expands so as to fill the time available for its completion. Quentin Tarantino’s Pie Principle: “…you want to go home have a drink and go and eat pie and talk about it.” (OK, he was talking about movies, not software, but I couldn’t find a “Q” quote about software. And wouldn’t it be cool to write a program so great that the users want to eat pie and talk about it?) Raymond’s Rule: Computer science education cannot make anybody an expert programmer any more than studying brushes and pigment can make somebody an expert painter.  Sowa's Law of Standards: Whenever a major organization develops a new system as an official standard for X, the primary result is the widespread adoption of some simpler system as a de facto standard for X. Turing’s Tenet: We shall do a much better programming job, provided we approach the task with a full appreciation of its tremendous difficulty, provided that we respect the intrinsic limitations of the human mind and approach the task as very humble programmers.  Udi Dahan’s Race Condition Rule: If you think you have a race condition, you don’t understand the domain well enough. These rules didn’t exist in the age of paper, there is no reason for them to exist in the age of computers. When you have race conditions, go back to the business and find out actual rules. Van Vleck’s Kvetching: We know about as much about software quality problems as they knew about the Black Plague in the 1600s. We've seen the victims' agonies and helped burn the corpses. We don't know what causes it; we don't really know if there is only one disease. We just suffer -- and keep pouring our sewage into our water supply. Wheeler’s Law: All problems in computer science can be solved by another level of indirection... Except for the problem of too many layers of indirection. Wheeler also said “Compatibility means deliberately repeating other people's mistakes.”. The Wrong Road Rule of Mr. X (anonymous): No matter how far down the wrong road you've gone, turn back. Yourdon’s Rule of Two Feet: If you think your management doesn't know what it's doing or that your organisation turns out low-quality software crap that embarrasses you, then leave. Zawinski's Law of Software Envelopment: Every program attempts to expand until it can read mail. Zawinski is also responsible for “Some people, when confronted with a problem, think 'I know, I'll use regular expressions.' Now they have two problems.” He once commented about X Windows widget toolkits: “Using these toolkits is like trying to make a bookshelf out of mashed potatoes.”

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  • Geocaching - World wide treasure hunt

    I'm not quite sure how I came across this topic but actually I find it absolutely interesting, challenging and most of all a great fun for the family and friends. The interesting part is for sure that you can follow other peoples treasures and their preferred locations where a cache might be hidden. Of course, it wont be easy to find a cache after all. Sometimes there are even 'mystery caches' which have either riddles, further instructions or little brain games for you in order to find the actual cache - that's the challenge. And last but not least, those caches are hidden outdoor. A great experience to explore nature either on your own, or your family especially with children, or as a treasure hunting pack with a couple of friends. What is geocaching? It's a high-tech outdoor treasure hunting game that's a great way to explore the world with friends, family or on your own. Participants use GPS-enabled devices to locate hidden containers called geocaches. There are over one million geocaches hidden around the world today, waiting for you to find them. Visit Geocaching.com to search for geocaches near you.(Source: Referral Email of geocaching.com) Checkout the Geocaching 101 for further details and information. They also provide a video channel on YouTube. Which equipment do I need? Any GPS-enabled device is sufficient to go onto the hunt. I'm going to start our geocaching experience equipped with my Samsung Galaxy Tab. Additionally, I installed a geocaching.com client called c:geo that hopefully assists me soon. Combined with a map app like Google Maps and a nice Compass app you should be fully equipped and ready to go. I guess, that even a car navigation system is perfect for that task. Later on, with more experience and demand for technology (or precision) it might be interesting to opt-in for a pure GPS device, like a Garmin or any other brand on the market. {loadposition content_adsense} What is a geocache and what does it contain? In its simplest form, a cache always contains a logbook or logsheet for you to log your find. Larger caches may contain a logbook and any number of items. These items turn the adventure into a true treasure hunt. You never know what the cache owner or visitors to the cache may have left for you to enjoy. Remember, if you take something, leave something of equal or greater value in return. It is recommended that items in a cache be individually packaged in a clear, zipped plastic bag to protect them from the elements. Finding your first geocache Well, first you have to have interest to pick up the challenge. Then you have to check out the Geocache directory on geocaching.com. They have recommendations for beginner's caches but you are free to choose any. Actually, we have a Mystery Cache very close to our base, and I guess that we are going for that one on our first trip. Anyway, there is a very informative guide on the website which should answer all your questions about starting your new outdoor adventure. For sure, it's going to be rewarding. Team up with friends and family Especially as a beginner there might be misunderstandings in handling the GPS coordinates, the compass, or the map, and even finding the container at the documented position isn't easy in the first place. Luckily, there are logbook reports online from other hunters, and most of the time there are even 'spoiler' images available. But also bear in mind, that a geocache might have been removed or is lost due to unconscious people or whatever other reasons. Don't be disappointed in case that you can't find anything... There be nothing anymore. A general recommendation in this case would be to replace the missing container with a new one, and give feedback to the original owner about the state of that particular location. After all, it's about fun and active participation in a world-wide community. Geocaches in Mauritius? Yes, there are currently about 45 geocaches spread all over the island, and even a single in Rodriguez - that's gonna be a tough one. Hopefully, we will get increasing numbers as Geocaching.com allows, no better, even encourages you to hide new containers at your locations of choice. I think this is going to be real fun for us during the upcoming weeks and months. Especially, when we are travelling to other countries and transfer so-called trackable items between geocaches. On my first impression, Geocaching.com seems to be very mature, open and community-oriented. There are literally hundreds of thousands geocache 'hunters' all over the world. And usually finding a container remote from your home is very rewarding. I'll keep you updated in these matters during the next months to come...

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  • Setup and Use SpecFlow BDD with DevExpress XAF

    - by Patrick Liekhus
    Let’s get started with using the SpecFlow BDD syntax for writing tests with the DevExpress XAF EasyTest scripting syntax.  In order for this to work you will need to download and install the prerequisites listed below.  Once they are installed follow the steps outlined below and enjoy. Prerequisites Install the following items: DevExpress eXpress Application Framework (XAF) found here SpecFlow found here Liekhus BDD/XAF Testing library found here Assumptions I am going to assume at this point that you have created your XAF application and have your Module, Win.Module and Win ready for usage.  You should have also set any attributes and/or settings as you see fit. Setup So where to start. Create a new testing project within your solution. I typically call this with a similar naming convention as used by XAF, my project name .FunctionalTests (i.e. AlbumManager.FunctionalTests). Add the following references to your project.  It should look like the reference list below. DevExpress.Data.v11.x DevExpress.Persistent.Base.v11.x DevExpress.Persistent.BaseImpl.v11.x DevExpress.Xpo.v11.2 Liekhus.Testing.BDD.Core Liekhus.Testing.BDD.DevExpress TechTalk.SpecFlow TestExecutor.v11.x (found in %Program Files%\DevExpress 2011.x\eXpressApp Framework\Tools\EasyTest Right click the TestExecutor reference and set the “Copy Local” setting to True.  This forces the TestExecutor executable to be available in the bin directory which is where the EasyTest script will be executed further down in the process. Add an Application Configuration File (app.config) to your test application.  You will need to make a few modifications to have SpecFlow generate Microsoft style unit tests.  First add the section handler for SpecFlow and then set your choice of testing framework.  I prefer MS Tests for my projects. Add the EasyTest configuration file to your project.  Add a new XML file and call it Config.xml. Open the properties window for the Config.xml file and set the “Copy to Ouput Directory” to “Copy Always”. You will setup the Config file according to the specifications of the EasyTest library my mapping to your executable and other settings.  You can find the details for the configuration of EasyTest here.  My file looks like this Create a new folder in your test project called “StepDefinitions”.  Add a new SpecFlow Step Definition file item under the StepDefinitions folder.  I typically call this class StepDefinition.cs. Have your step definition inherit from the Liekhus.Testing.BDD.DevExpress.StepDefinition class.  This will give you the default behaviors for your test in the next section. OK.  Now that we have done this series of steps, we will work on simplifying this.  This is an early preview of this new project and is not fully ready for consumption.  If you would like to experiment with it, please feel free.  Our goals are to make this a installable project on it’s own with it’s own project templates and default settings.  This will be coming in later versions.  Currently this project is in Alpha release. Let’s write our first test Remove the basic test that is created for you. We will not use the default test but rather create our own SpecFlow “Feature” files. Add a new item to your project and select the SpecFlow Feature file under C#. Name your feature file as you do your class files after the test they are performing. Writing a feature file uses the Cucumber syntax of Given… When… Then.  Think of it in these terms.  Givens are the pre-conditions for the test.  The Whens are the actual steps for the test being performed.  The Thens are the verification steps that confirm your test either passed or failed.  All of these steps are generated into a an EasyTest format and executed against your XAF project.  You can find more on the Cucumber syntax by using the Secret Ninja Cucumber Scrolls.  This document has several good styles of tests, plus you can get your fill of Chuck Norris vs Ninjas.  Pretty humorous document but full of great content. My first test is going to test the entry of a new Album into the application and is outlined below. The Feature section at the top is more for your documentation purposes.  Try to be descriptive of the test so that it makes sense to the next person behind you.  The Scenario outline is described in the Ninja Scrolls, but think of it as test template.  You can write one test outline and have multiple datasets (Scenarios) executed against that test.  Here are the steps of my test and their descriptions Given I am starting a new test – tells our test to create a new EasyTest file And (Given) the application is open – tells EasyTest to open our application defined in the Config.xml When I am at the “Albums” screen – tells XAF to navigate to the Albums list view And (When) I click the “New:Album” button – tells XAF to click the New Album button on the ribbon And (When) I enter the following information – tells XAF to find the field on the screen and put the value in that field And (When) I click the “Save and Close” button – tells XAF to click the “Save and Close” button on the detail window Then I verify results as “user” – tells the testing framework to execute the EasyTest as your configured user Once you compile and prepare your tests you should see the following in your Test View.  For each of your CreateNewAlbum lines in your scenarios, you will see a new test ready to execute. From here you will use your testing framework of choice to execute the test.  This in turn will execute the EasyTest framework to call back into your XAF application and test your business application. Again, please remember that this is an early preview and we are still working out the details.  Please let us know if you have any comments/questions/concerns. Thanks and happy testing.

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  • Microsoft Sql Server driver for Nodejs - Part 2

    - by chanderdhall
    Nodejs, Sql server and Json response with Rest This post is part 2 of Microsoft Sql Server driver for Node js.In this post we will look at the JSON responses from the Microsoft Sql Server driver for Node js. Pre-requisites: If you have read the Part 1 of the series, you should be good. We will be using a framework for Rest within Nodejs - Restify, but that would need no prior learning. Restify: Restify is a simple node module for building RESTful services. It is slimmer than Express. Express is a complete module that has all what you need to create a full-blown browser app. However, Restify does not have additional overhead of templating, rendering etc that would be needed if your app has views. So, as the name suggests it's an awesome framework for building RESTful services and is very light-weight. Set up - You can continue with the same directory or project structure we had in the previous post, or can start a new one. Install restify using npm and you are good to go. npm install restify Go to Server.js and include Restify in your solution. Then create the server object using restify.CreateServer() - SLICK - ha? var restify = require('restify'); var server = restify.createServer(); server.listen(8080, function () { console.log('%s listening at %s', server.name, server.url); }); Then make sure you provide a port for the Server to listen at. The call back function is optional but helps you for debugging purposes. Once you are done, save the file and then go to the command prompt and hit 'node server.js' and you should see the following:   To test the server, go to your browser and type the address 'http://localhost:8080/' and oops you will see an error.   Why is that? - Well because we haven't defined any routes. Let's go ahead and create a route. To begin with I'd like to return whatever is typed in the url after my name and the following code should do it. server.get('/ChanderDhall/:status', function respond(req, res, next) { res.end("hello " + req.params.name + "") }); You can also avoid writing call backs inline. Something like this. function respond(req, res, next) { res.end("Chander Dhall " + req.params.name + ""); } server.get('/hello/:name', respond); Now if you go ahead and type http://localhost:8080/ChanderDhall/LovesNode you will get the response 'Chander Dhall loves node'. NOTE: Make sure your url has the right case as it's case-sensitive. You could have also typed it in as 'server.get('/chanderdhall/:name', respond);' Stored procedure: We've talked a lot about Restify now, but keep in mind the post is about being able to use Sql server with Node and return JSON. To see this in action, let's go ahead and create another route to a list of Employees from a stored procedure. server.get('/Employees', Employees); The following code will return a JSON response.  function Employees(req, res, next) { res.header("Content-Type: application/json"); //Need to specify the Content-Type which is //JSON in our case. sql.open(conn_str, function (err, conn) { if (err) { //Logs an error console.log("Error opening the database connection!"); return; } console.log("before query!"); conn.queryRaw("exec sp_GetEmployees", function (err, results) { if (err) { //Connection is open but an error occurs whileWhat else can be done? May be create a formatter or may be even come up with a hypermedia type but that may upset some pragmatists. Well, that's going to be a totally different discussion and is really not part of this series. Summary: We've discussed how to execute a stored procedure using Microsoft Sql Server driver for Node. Also, we have discussed how to format and send out a clean JSON to the app calling this API.  

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  • CodePlex Daily Summary for Sunday, April 18, 2010

    CodePlex Daily Summary for Sunday, April 18, 2010New ProjectsBare Bones Email Trace Listener: Bare Bones Email Trace Listener is about the simplest email trace listener you can have. No bells, no whistles, and no good if you need authenticat...Cartellino: Scopo del progetto è la realizzazione di un software in grado di rilevare i dati dai rilevatori 3Tec (www.3tec.it) e stampare i cartellini presenza...Castle Windsor app.config Properties: The Castle Windsor app.config Properties library makes it possible for users of Castle Windsor to reference appSettings values in Windsor's XML pro...DeskD: This is a simple desktop dictionary application(something like WordWeb) created in Java using Netbeans IDE. Since i am new to codeplex all updates ...FunPokerMakerOnline: It is a play of poker online with a game editor. It is done with .net 4 and WPF and SOAP or WCF. KLOCS Team GIN Project: This is a Master's Degree program group project. It may have academic interest, but won't be maintained after June 2010KNN: This is KNN projectProject Santa: Program to organize teams using mysql databases and c# in a clean and robust task and group system. For more information see my blog post at http:/...ProjetoIntegradoJuridico: Sistema Integrado de Acompanhamento JurídicoRSSR for Windows Phone 7: This is a simple RSS reader application, the project aims to show people that it is easy to build application for windows phones. The applicatio...Simple Rcon: Simple Rcon is a simple lightweight rcon client for HL1/HL2 Servers. It is developed in C# and WPFTAB METHOD SQL Create a data dictionary from your Transact SQL code: TABMETHODSQL makes it easier for data/information workers to document their work. Create a data governance solution that maps sql data process, inc...TM BF Tournament: WPF software to manage Trackmania tournament with Battle France RulesviBlog: visinia plugin, this plugin is used to add blogging facility in visinia cmsviNews: visinia plugin, this plugin can be used to create a news portal like cnn.com nytimeVolumeMaster: VolumeMaster is an On Screen Display (OSD) that gets activated whenever the volume changes. It's written in WPF and uses Vista Core Audio API by Ra...WiiCIS.NET: This is a managed port of WiiCIS, which is a Nintendo Wiimote library originally created by TheOboeNerd and posted on Sourceforge.New ReleasesCastle Windsor app.config Properties: Version 1.0: Initial release.Code for Rapid C# Windows Development eBook: Enumerable Debugger Visualizer Version 1.1: Second release of the Enumerable Debugger Visualizer. There are more classes registered and it is more robust. The list of classes I have register...Convection Game Engine (Basic Edition): Convection Basic (40223): Compiled version of Convection Basic change set 40223.CycleMania Starter Kit EAP - ASP.NET 4 Problem - Design - Solution: Cyclemania 0.08.59: See Source Code tab for recent change history.DbEntry.Net (Lephone Framework): DbEntry.Net 3.9: DbEntry.Net is a lightweight Object Relational Mapping (ORM) database access compnent for .Net 3.5. It has clearly and easily programing interface ...Hash Calculator: HashCalculator 2.0: Upgraded to .NET Framework 4.0 Added support to calculate CRC32 hash function Added "Cancel" button in the Windows 7 taskbar thumbnailHKGolden Express: HKGoldenExpress (Build 201004172120): New features: Added jump links at top of page of message. Bug fix: Fixed page count bug. Improvements: HKGolden Express now uses DocumentBuild...HTML Ruby: 6.21.4: Styles added to override those on some sites for better rendering of ruby Fix regression on complex ruby annotation rendering Better spacingHTML Ruby: 6.21.5: Removed debug code in preference handling Status bar indicator now resets for each action Replace ruby in place without using document fragment...IceChat: IceChat 2009 Alpha 12.4 EXE Update: This is simply an update to the main IceChat program files and DLL. Simpply overwrite the ones in the place where IceChat 2009 is installed.IceChat: IceChat 2009 Alpha 12.4 Full Install: Build Alpha 12.4 - April 17 2010 Added IceChatScript.dll , needs to be added in same folder with EXE and IPluginIceChat.dll Added Self Notice in ...PokeIn Comet Ajax Library: PokeIn Library v05 x64: With this version, PokeIn library has become a stable. Numerous tests have completed. This is the first release candidate of PokeIn. Cheers!PokeIn Comet Ajax Library: PokeIn Library v05 x86: PokeIn Library version 0.5 (x86) With this version, PokeIn library has become a stable. Numerous tests have completed. This is the first release c...Project Santa: Project Santa V1.0: The first initial release of my project manager program, for more information see http://coderplex.blogspot.com/2010/04/project-manager-using-mysq...Salient: TestingWithVSDevServer v1: Using code from Salient, I have assembled a few strategies for programmatic contol of the Visual Studio Development Server (WebDev.WebServer.exe). ...SharePoint Navigation Menu: spNavigationMenu 1.1: Changed the CAML query so it will order by Link Order, then Title. Added the ability to override the On Hover event on the parent menu to use On ...Simple Rcon: Simple Rcon Version 1: Version 1TAB METHOD SQL Create a data dictionary from your Transact SQL code: RELEASE 1: TESTING THE RELEASE SYSTEMTribe.Cache: Tribe.Cache Beta 0.1: Beta release of Tribe.Cache - Now with cache expiration serviceviBlog: viBlog_beta: visinia plugin to add blogging facility in visinia cmsviNews: viNews_beta: visinia plugin.visinia: visinia_beta2: visinia beta 2 released with many new feature.Visual Studio DSite: Visual C++ 2008 Login Form: A simple login form made in visual c 2008. Source code only.WiiCIS.NET: WiiCIS.NET v0.11: 0.11 Removed an unnecessary function from the Wiimote class, and improved the demo. You will need the latest version of SlimDX to compile the sourc...WinControls TreeListView: TreeListView 1.5.1: -fixes issue #5837 -Preliminary feature #5874WoW Character Viewer: Viewer Setup: Finally, I've brought out the next setup of WoW Viewer. Most loose ends have been tied up. Loading and Saving of character files has been fixed.Most Popular ProjectsRawrAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseMicrosoft SQL Server Community & Samplespatterns & practices – Enterprise LibraryPHPExcelFacebook Developer ToolkitBlogEngine.NETMvcContrib: a Codeplex Foundation projectIronPythonMost Active ProjectsRawrpatterns & practices – Enterprise LibraryIndustrial DashboardFarseer Physics EnginejQuery Library for SharePoint Web ServicesIonics Isapi Rewrite FilterGMap.NET - Great Maps for Windows Forms & PresentationProxi [Proxy Interface]BlogEngine.NETCaliburn: An Application Framework for WPF and Silverlight

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  • Developer Training – Difficult Questions and Alternative Perspective – Part 3

    - by pinaldave
    Developer Training - Importance and Significance - Part 1 Developer Training – Employee Morals and Ethics – Part 2 Developer Training – Difficult Questions and Alternative Perspective - Part 3 Developer Training – Various Options for Developer Training – Part 4 Developer Training – A Conclusive Summary- Part 5 Congratulations!  You are now a fully trained developer!  You spent hours in a classroom, watching webinars, and reading materials.  You are now more educated and more prepared than ever before.  Now what? Stay or Quit The simple answer is that you now have two options – stay where you are or move on to a new job.  Even though you might now be smarter than you have ever felt before, this can still be a tough decision to make.  You feel extra trained and ready for a promotion or a raise, but you and your employer might not see eye to eye on this issue.  The logical conclusion is to go on a job hunt, but that might not be the most ethical thing to do. Click Image to Enlarge Manager’s Perspective Click Image to Enlarge Try to see the issue from your manager’s perspective.  You feel that you have just spent a lot of time and energy getting trained, and you should be rewarded.  But they have invested their time and energy in you.  They might see the training as a way to help you complete the goals they require from you, or as a way to help you complete tasks that will ultimately end in a reward or promotion. Moral Compass As in most cases, honesty is the best policy.  Be open with your manager about your expectations, and ask them to explain their goals.  When there is open and honest communication, everyone can walk away happy.  If you’re unable to discuss with your manager for one reason or another, just try to keep the company policy in mind and follow your own moral compass.  If all else fails, and your company is unwilling to make allowances for your new value, offer to pay the company back for the training before moving on your way. Whether you stay at your old job or move on to a new one, you are still faced with the question of what you’re going to do with all your new knowledge.  If you feel comfortable, offer to train others around you who are interested in the same subject.  This can look very good on your resume, and if you are working in a team environment it is sure to help you in the long run! What Next? You can even offer to train other trainers at the company – managers, those above you, or even report back to your original trainer about how your education is helping you in the work place.  Obviously this should be completely voluntary on the trainer’s part.  Taking advice from a “newbie” may not be their favorite idea, but it could also show the company that you are open to expanding your horizons and being helpful to everyone around you. Last in Line for Opportunity Click Image to Enlarge At this time, let us address a subject related to training and what to do with it – what if you are always overlooked for training?  This can as thorny a problem as receiving training in the first place.  The best advice is to let your supervisors know that you are always open to training and very interested in certain topics.  If you are consistently passed over, be patient.  Your turn will probably come, but the company as a whole has to focus on other problems at the moment.  If you feel that there are more personal issues at play, be sure to bring this up with your supervisor in a calm and professional manager so that everything can be worked out best for both parties. You, Yourself and Your Future! If all else fails, offer to pay for training yourself.  Perhaps money problems are at the root of being passed over.  Even if there are other reasons, offering to pay your own way shows your dedication and could work out well for you in the long run.  Always remember – in life you have to go out and make your own way, you cannot always sit and wait for things to land in your lap. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Developer Training, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • techniques for an AI for a highly cramped turn-based tactics game

    - by Adam M.
    I'm trying to write an AI for a tactics game in the vein of Final Fantasy Tactics or Vandal Hearts. I can't change the game rules in any way, only upgrade the AI. I have experience programming AI for classic board games (basically minimax and its variants), but I think the branching factor is too great for the approach to be reasonable here. I'll describe the game and some current AI flaws that I'd like to fix. I'd like to hear ideas for applicable techniques. I'm a decent enough programmer, so I only need the ideas, not an implementation (though that's always appreciated). I'd rather not expend effort chasing (too many) dead ends, so although speculation and brainstorming are good and probably helpful, I'd prefer to hear from somebody with actual experience solving this kind of problem. For those who know it, the game is the land battle mini-game in Sid Meier's Pirates! (2004) and you can skim/skip the next two paragraphs. For those who don't, here's briefly how it works. The battle is turn-based and takes place on a 16x16 grid. There are three terrain types: clear (no hindrance), forest (hinders movement, ranged attacks, and sight), and rock (impassible, but does not hinder attacks or sight). The map is randomly generated with roughly equal amounts of each type of terrain. Because there are many rock and forest tiles, movement is typically very cramped. This is tactically important. The terrain is not flat; higher terrain gives minor bonuses. The terrain is known to both sides. The player is always the attacker and the AI is always the defender, so it's perfectly valid for the AI to set up a defensive position and just wait. The player wins by killing all defenders or by getting a unit to the city gates (a tile on the other side of the map). There are very few units on each side, usually 4-8. Because of this, it's crucial not to take damage without gaining some advantage from it. Units can take multiple actions per turn. All units on one side move before any units on the other side. Order of execution is important, and interleaving of actions between units is often useful. Units have melee and ranged attacks. Melee attacks vary widely in strength; ranged attacks have the same strength but vary in range. The main challenges I face are these: Lots of useful move combinations start with a "useless" move that gains no immediate advantage, or even loses advantage, in order to set up a powerful flank attack in the future. And, since the player units are stronger and have longer range, the AI pretty much always has to take some losses before they can start to gain kills. The AI must be able to look ahead to distinguish between sacrificial actions that provide a future benefit and those that don't. Because the terrain is so cramped, most of the tactics come down to achieving good positioning with multiple units that work together to defend an area. For instance, two defenders can often dominate a narrow pass by positioning themselves so an enemy unit attempting to pass must expose itself to a flank attack. But one defender in the same pass would be useless, and three units can defend a slightly larger pass. Etc. The AI should be able to figure out where the player must go to reach the city gates and how to best position its few units to cover the approaches, shifting, splitting, or combining them appropriately as the player moves. Because flank attacks are extremely deadly (and engineering flank attacks is key to the player strategy), the AI should be competent at moving its units so that they cover each other's flanks unless the sacrifice of a unit would give a substantial benefit. They should also be able to force flank attacks on players, for instance by threatening a unit from two different directions such that responding to one threat exposes the flank to the other. The AI should attack if possible, but sometimes there are no good ways to approach the player's position. In that case, the AI should be able to recognize this and set up a defensive position of its own. But the AI shouldn't be vulnerable to a trivial exploit where the player repeatedly opens and closes a hole in his defense and shoots at the AI as it approaches and retreats. That is, the AI should ideally be able to recognize that the player is capable of establishing a solid defense of an area, even if the defense is not currently in place. (I suppose if a good unit allocation algorithm existed, as needed for the second bullet point, the AI could run it on the player units to see where they could defend.) Because it's important to choose a good order of action and interleave actions between units, it's not as simple as just finding the best move for each unit in turn. All of these can be accomplished with a minimax search in theory, but the search space is too large, so specialized techniques are needed. I thought about techniques such as influence mapping, but I don't see how to use the technique to great effect. I thought about assigning goals to the units. This can help them work together in some limited way, and the problem of "how do I accomplish this goal?" is easier to solve than "how do I win this battle?", but assigning good goals is a hard problem in itself, because it requires knowing whether the goal is achievable and whether it's a good use of resources. So, does anyone have specific ideas for techniques that can help cleverize this AI? Update: I found a related question on Stackoverflow: http://stackoverflow.com/questions/3133273/ai-for-a-final-fantasy-tactics-like-game The selected answer gives a decent approach to choosing between alternative actions, but it doesn't seem to have much ability to look into the future and discern beneficial sacrifices from wasteful ones. It also focuses on a single unit at a time and it's not clear how it could be extended to support cooperation between units in defending or attacking.

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  • SQL SERVER – Fundamentals of Columnstore Index

    - by pinaldave
    There are two kind of storage in database. Row Store and Column Store. Row store does exactly as the name suggests – stores rows of data on a page – and column store stores all the data in a column on the same page. These columns are much easier to search – instead of a query searching all the data in an entire row whether the data is relevant or not, column store queries need only to search much lesser number of the columns. This means major increases in search speed and hard drive use. Additionally, the column store indexes are heavily compressed, which translates to even greater memory and faster searches. I am sure this looks very exciting and it does not mean that you convert every single index from row store to column store index. One has to understand the proper places where to use row store or column store indexes. Let us understand in this article what is the difference in Columnstore type of index. Column store indexes are run by Microsoft’s VertiPaq technology. However, all you really need to know is that this method of storing data is columns on a single page is much faster and more efficient. Creating a column store index is very easy, and you don’t have to learn new syntax to create them. You just need to specify the keyword “COLUMNSTORE” and enter the data as you normally would. Keep in mind that once you add a column store to a table, though, you cannot delete, insert or update the data – it is READ ONLY. However, since column store will be mainly used for data warehousing, this should not be a big problem. You can always use partitioning to avoid rebuilding the index. A columnstore index stores each column in a separate set of disk pages, rather than storing multiple rows per page as data traditionally has been stored. The difference between column store and row store approaches is illustrated below: In case of the row store indexes multiple pages will contain multiple rows of the columns spanning across multiple pages. In case of column store indexes multiple pages will contain multiple single columns. This will lead only the columns needed to solve a query will be fetched from disk. Additionally there is good chance that there will be redundant data in a single column which will further help to compress the data, this will have positive effect on buffer hit rate as most of the data will be in memory and due to same it will not need to be retrieved. Let us see small example of how columnstore index improves the performance of the query on a large table. As a first step let us create databaseset which is large enough to show performance impact of columnstore index. The time taken to create sample database may vary on different computer based on the resources. USE AdventureWorks GO -- Create New Table CREATE TABLE [dbo].[MySalesOrderDetail]( [SalesOrderID] [int] NOT NULL, [SalesOrderDetailID] [int] NOT NULL, [CarrierTrackingNumber] [nvarchar](25) NULL, [OrderQty] [smallint] NOT NULL, [ProductID] [int] NOT NULL, [SpecialOfferID] [int] NOT NULL, [UnitPrice] [money] NOT NULL, [UnitPriceDiscount] [money] NOT NULL, [LineTotal] [numeric](38, 6) NOT NULL, [rowguid] [uniqueidentifier] NOT NULL, [ModifiedDate] [datetime] NOT NULL ) ON [PRIMARY] GO -- Create clustered index CREATE CLUSTERED INDEX [CL_MySalesOrderDetail] ON [dbo].[MySalesOrderDetail] ( [SalesOrderDetailID]) GO -- Create Sample Data Table -- WARNING: This Query may run upto 2-10 minutes based on your systems resources INSERT INTO [dbo].[MySalesOrderDetail] SELECT S1.* FROM Sales.SalesOrderDetail S1 GO 100 Now let us do quick performance test. I have kept STATISTICS IO ON for measuring how much IO following queries take. In my test first I will run query which will use regular index. We will note the IO usage of the query. After that we will create columnstore index and will measure the IO of the same. -- Performance Test -- Comparing Regular Index with ColumnStore Index USE AdventureWorks GO SET STATISTICS IO ON GO -- Select Table with regular Index SELECT ProductID, SUM(UnitPrice) SumUnitPrice, AVG(UnitPrice) AvgUnitPrice, SUM(OrderQty) SumOrderQty, AVG(OrderQty) AvgOrderQty FROM [dbo].[MySalesOrderDetail] GROUP BY ProductID ORDER BY ProductID GO -- Table 'MySalesOrderDetail'. Scan count 1, logical reads 342261, physical reads 0, read-ahead reads 0. -- Create ColumnStore Index CREATE NONCLUSTERED COLUMNSTORE INDEX [IX_MySalesOrderDetail_ColumnStore] ON [MySalesOrderDetail] (UnitPrice, OrderQty, ProductID) GO -- Select Table with Columnstore Index SELECT ProductID, SUM(UnitPrice) SumUnitPrice, AVG(UnitPrice) AvgUnitPrice, SUM(OrderQty) SumOrderQty, AVG(OrderQty) AvgOrderQty FROM [dbo].[MySalesOrderDetail] GROUP BY ProductID ORDER BY ProductID GO It is very clear from the results that query is performance extremely fast after creating ColumnStore Index. The amount of the pages it has to read to run query is drastically reduced as the column which are needed in the query are stored in the same page and query does not have to go through every single page to read those columns. If we enable execution plan and compare we can see that column store index performance way better than regular index in this case. Let us clean up the database. -- Cleanup DROP INDEX [IX_MySalesOrderDetail_ColumnStore] ON [dbo].[MySalesOrderDetail] GO TRUNCATE TABLE dbo.MySalesOrderDetail GO DROP TABLE dbo.MySalesOrderDetail GO In future posts we will see cases where Columnstore index is not appropriate solution as well few other tricks and tips of the columnstore index. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Index, SQL Optimization, SQL Performance, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Recent Innovations to ILOM

    - by B.Koch
    by Josh Rosen If you are wondering how Oracle can make some of the most advanced, reliable, and fault tolerant servers on the market, look no further than Oracle Integrated Lights Out Manager or ILOM.  We build ILOM into every server we create, from Oracle x86 Systems such as X3-2 to the SPARC T-Series family. Oracle ILOM is an embedded service processor, but it's really more than that.  It's a computer within a computer.  It's smart, it's tightly integrated into all aspects of the server's operation, and it's a big reason why Oracle servers are used for some of the most mission-critical workloads out there. To understand the value of ILOM, there is no better place to start than its fault management capability.  We have taken the sophisticated fault management architecture from Solaris, developed and refined over a decade, and built it into each and every ILOM. ILOM detects a potential issue at its earliest stage, watching low-level sensors.   If the root cause of a problem is not clear from a single error reading, ILOM will look for other clues and combine multiple pieces of information to correctly identify a failing component. ILOM provides peace of mind. We tailor our fault management for each new server platform that we produce.  You can rest assured that it's always actively keeping the server healthy.  And if there is a problem, you can be confident it will let you know by sending you a notification by e-mail or trap. We also heard IT managers tell us they needed a Ph.D. in computer engineering to manage today's servers. It doesn't have to be that way.  Thanks to the latest innovations to Oracle ILOM, we present hardware inventory and status in way that makes sense – to anyone.  Green means everything is healthy and red means something is wrong.  When a component needs to be replaced a clear message indicates where the problem is and points you at a knowledge article about that problem.  It's that simple. Simpler management and simple interfaces mean reduced complexity and lower costs to manage.  And we know that's really important. ILOM does all this while also providing advanced service processor features you depend on for managing enterprise class systems.  You can remotely control the server power, interact with a virtual video console for the server, and mount media on the server remotely.  There is no need to spend money on a KVM switch to get this functionality. And when people hear how advanced ILOM is, they can't believe ILOM is free.  All features are enabled and included with each Oracle server that you buy.  There are no advanced licenses you need to purchase or features to unlock. Configuring ILOM has also never been easier.  It is now possible to configure almost all aspects of the server directly from ILOM.  This includes changing BIOS settings, persistently modifying boot order, and optimizing power settings -- all directly from ILOM. But Oracle's innovation does not stop with ILOM.  Oracle has engineered Oracle Enterprise Manager Ops Center to integrate directly with ILOM, providing centralized management across all of our servers. Ops Center will discover each of your Oracle servers over the network by searching for ILOMs.  When it finds one, it knows how to communicate with ILOM to monitoring and configure that server from application to disk. Since every server that Oracle produces, from x86 Systems to SPARC T-Series up and down the line, comes with Oracle ILOM, you can manage all Oracle servers in the same way.  And while all of our servers may have different components on the inside, each with their specialized functions, the way you integrate them and the way you monitor and manage them is exactly the same. Oracle ILOM is state-of-art.  If you are looking for a server that make systems management simple and is easy to integrate and maintain, check out the latest advances to Oracle ILOM. Josh Rosen is a Principal Product Manager at Oracle and previously spent more than a decade as a developer and architect of system management software. Josh has worked on system management for many of Oracle's hardware products ranging from the earliest blade systems to the latest Oracle x86 servers.

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  • Handling HumanTask attachments in Oracle BPM 11g PS4FP+ (I)

    - by ccasares
    Adding attachments to a HumanTask is a feature that exists in Oracle HWF (Human Workflow) since 10g. However, in 11g there have been many improvements on this feature and this entry will try to summarize them. Oracle BPM 11g 11.1.1.5.1 (aka PS4 Feature Pack or PS4FP) introduced two great features: Ability to link attachments at a Task scope or at a Process scope: "Task" attachments are only visible within the scope (lifetime) of a task. This means that, initially, any member of the assignment pattern of the Human Task will be able to handle (add, review or remove) attachments. However, once the task is completed, subsequent human tasks will not have access to them. This does not mean those attachments got lost. Once the human task is completed, attachments can be retrieved in order to, i.e., check them in to a Content Server or to inject them to a new and different human task. Aside note: a "re-initiated" human task will inherit comments and attachments, along with history and -optionally- payload. See here for more info. "Process" attachments are visible within the scope of the process. This means that subsequent human tasks in the same process instance will have access to them. Ability to use Oracle WebCenter Content (previously known as "Oracle UCM") as the backend for the attachments instead of using HWF database backend. This feature adds all content server document lifecycle capabilities to HWF attachments (versioning, RBAC, metadata management, etc). As of today, only Oracle WCC is supported. However, Oracle BPM Suite does include a license of Oracle WCC for the solely usage of document management within BPM scope. Here are some code samples that leverage the above features. Retrieving uploaded attachments -Non UCM- Non UCM attachments (default ones or those that have existed from 10g, and are stored "as-is" in HWK database backend) can be retrieved after the completion of the Human Task. Firstly, we need to know whether any attachment has been effectively uploaded to the human task. There are two ways to find it out: Through an XPath function: Checking the execData/attachment[] structure. For example: Once we are sure one ore more attachments were uploaded to the Human Task, we want to get them. In this example, by "get" I mean to get the attachment name and the payload of the file. Aside note: Oracle HWF lets you to upload two kind of [non-UCM] attachments: a desktop document and a Web URL. This example focuses just on the desktop document one. In order to "retrieve" an uploaded Web URL, you can get it directly from the execData/attachment[] structure. Attachment content (payload) is retrieved through the getTaskAttachmentContents() XPath function: This example shows how to retrieve as many attachments as those had been uploaded to the Human Task and write them to the server using the File Adapter service. The sample process excerpt is as follows:  A dummy UserTask using "HumanTask1" Human Task followed by a Embedded Subprocess that will retrieve the attachments (we're assuming at least one attachment is uploaded): and once retrieved, we will write each of them back to a file in the server using a File Adapter service: In detail: We've defined an XSD structure that will hold the attachments (both name and payload): Then, we can create a BusinessObject based on such element (attachmentCollection) and create a variable (named attachmentBPM) of such BusinessObject type. We will also need to keep a copy of the HumanTask output's execData structure. Therefore we need to create a variable of type TaskExecutionData... ...and copy the HumanTask output execData to it: Now we get into the embedded subprocess that will retrieve the attachments' payload. First, and using an XSLT transformation, we feed the attachmentBPM variable with the name of each attachment and setting an empty value to the payload: Please note that we're using the XSLT for-each node to create as many target structures as necessary. Also note that we're setting an Empty text to the payload variable. The reason for this is to make sure the <payload></payload> tag gets created. This is needed when we map the payload to the XML variable later. Aside note: We are assuming that we're retrieving non-UCM attachments. However in real life you might want to check the type of attachment you're handling. The execData/attachment[]/storageType contains the values "UCM" for UCM type attachments, "TASK" for non-UCM ones or "URL" for Web URL ones. Those values are part of the "Ext.Com.Oracle.Xmlns.Bpel.Workflow.Task.StorageTypeEnum" enumeration. Once we have fed the attachmentsBPM structure and so it now contains the name of each of the attachments, it is time to iterate through it and get the payload. Therefore we will use a new embedded subprocess of type MultiInstance, that will iterate over the attachmentsBPM/attachment[] element: In every iteration we will use a Script activity to map the corresponding payload element with the result of the XPath function getTaskAttachmentContents(). Please, note how the target array element is indexed with the loopCounter predefined variable, so that we make sure we're feeding the right element during the array iteration:  The XPath function used looks as follows: hwf:getTaskAttachmentContents(bpmn:getDataObject('UserTask1LocalExecData')/ns1:systemAttributes/ns1:taskId, bpmn:getDataObject('attachmentsBPM')/ns:attachment[bpmn:getActivityInstanceAttribute('SUBPROCESS3067107484296', 'loopCounter')]/ns:fileName)  where the input parameters are: taskId of the just completed Human Task attachment name we're retrieving the payload from array index (loopCounter predefined variable)  Aside note: The reason whereby we're iterating the execData/attachment[] structure through embedded subprocess and not, i.e., using XSLT and for-each nodes, is mostly because the getTaskAttachmentContents() XPath function is currently not available in XSLT mappings. So all this example might be considered as a workaround until this gets fixed/enhanced in future releases. Once this embedded subprocess ends, we will have all attachments (name + payload) in the attachmentsBPM variable, which is the main goal of this sample. But in order to test everything runs fine, we finish the sample writing each attachment to a file. To that end we include a final embedded subprocess to concurrently iterate through each attachmentsBPM/attachment[] element: On each iteration we will use a Service activity that invokes a File Adapter write service. In here we have two important parameters to set. First, the payload itself. The file adapter awaits binary data in base64 format (string). We have to map it using XPath (Simple mapping doesn't recognize a String as a base64-binary valid target):  Second, we must set the target filename using the Service Properties dialog box:  Again, note how we're making use of the loopCounter index variable to get the right element within the embedded subprocess iteration. Handling UCM attachments will be part of a different and upcoming blog entry. Once I finish will all posts on this matter, I will upload the whole sample project to java.net.

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  • Oracle Linux and Oracle VM pricing guide

    - by wcoekaer
    A few days ago someone showed me a pricing guide from a Linux vendor and I was a bit surprised at the complexity of it. Especially when you look at larger servers (4 or 8 sockets) and when adding virtual machine use into the mix. I think we have a very compelling and simple pricing model for both Oracle Linux and Oracle VM. Let me see if I can explain it in 1 page, not 10 pages. This pricing information is publicly available on the Oracle store, I am using the current public list prices. Also keep in mind that this is for customers using non-oracle x86 servers. When a customer purchases an Oracle x86 server, the annual systems support includes full use (all you can eat) of Oracle Linux, Oracle VM and Oracle Solaris (no matter how many VMs you run on that server, in case you deploy guests on a hypervisor). This support level is the equivalent of premier support in the list below. Let's start with Oracle VM (x86) : Oracle VM support subscriptions are per physical server on which you deploy the Oracle VM Server product. (1) Oracle VM Premier Limited - 1- or 2 socket server : $599 per server per year (2) Oracle VM Premier - more than 2 socket server (4, or 8 or whatever more) : $1199 per server per year The above includes the use of Oracle VM Manager and Oracle Enterprise Manager Cloud Control's Virtualization management pack (including self service cloud portal, etc..) 24x7 support, access to bugfixes, updates and new releases. It also includes all options, live migrate, dynamic resource scheduling, high availability, dynamic power management, etc If you want to play with the product, or even use the product without access to support services, the product is freely downloadable from edelivery. Next, Oracle Linux : Oracle Linux support subscriptions are per physical server. If you plan to run Oracle Linux as a guest on Oracle VM, VMWare or Hyper-v, you only have to pay for a single subscription per system, we do not charge per guest or per number of guests. In other words, you can run any number of Oracle Linux guests per physical server and count it as just a single subscription. (1) Oracle Linux Network Support - any number of sockets per server : $119 per server per year Network support does not offer support services. It provides access to the Unbreakable Linux Network and also offers full indemnification for Oracle Linux. (2) Oracle Linux Basic Limited Support - 1- or 2 socket servers : $499 per server per year This subscription provides 24x7 support services, access to the Unbreakable Linux Network and the Oracle Support portal, indemnification, use of Oracle Clusterware for Linux HA and use of Oracle Enterprise Manager Cloud control for Linux OS management. It includes ocfs2 as a clustered filesystem. (3) Oracle Linux Basic Support - more than 2 socket server (4, or 8 or more) : $1199 per server per year This subscription provides 24x7 support services, access to the Unbreakable Linux Network and the Oracle Support portal, indemnification, use of Oracle Clusterware for Linux HA and use of Oracle Enterprise Manager Cloud control for Linux OS management. It includes ocfs2 as a clustered filesystem (4) Oracle Linux Premier Limited Support - 1- or 2 socket servers : $1399 per server per year This subscription provides 24x7 support services, access to the Unbreakable Linux Network and the Oracle Support portal, indemnification, use of Oracle Clusterware for Linux HA and use of Oracle Enterprise Manager Cloud control for Linux OS management, XFS filesystem support. It also offers Oracle Lifetime support, backporting of patches for critical customers in previous versions of package and ksplice zero-downtime updates. (5) Oracle Linux Premier Support - more than 2 socket servers : $2299 per server per year This subscription provides 24x7 support services, access to the Unbreakable Linux Network and the Oracle Support portal, indemnification, use of Oracle Clusterware for Linux HA and use of Oracle Enterprise Manager Cloud control for Linux OS management, XFS filesystem support. It also offers Oracle Lifetime support, backporting of patches for critical customers in previous versions of package and ksplice zero-downtime updates. (6) Freely available Oracle Linux - any number of sockets You can freely download Oracle Linux, install it on any number of servers and use it for any reason, without support, without right to use of these extra features like Oracle Clusterware or ksplice, without indemnification. However, you do have full access to all errata as well. Need support? then use options (1)..(5) So that's it. Count number of 2 socket boxes, more than 2 socket boxes, decide on basic or premier support level and you are done. You don't have to worry about different levels based on how many virtual instance you deploy or want to deploy. A very simple menu of choices. We offer, inclusive, Linux OS clusterware, Linux OS Management, provisioning and monitoring, cluster filesystem (ocfs), high performance filesystem (xfs), dtrace, ksplice, ofed (infiniband stack for high performance networking). No separate add-on menus. NOTE : socket/cpu can have any number of cores. So whether you have a 4,6,8,10 or 12 core CPU doesn't matter, we count the number of physical CPUs.

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  • Simple-Talk development: a quick history lesson

    - by Michael Williamson
    Up until a few months ago, Simple-Talk ran on a pure .NET stack, with IIS as the web server and SQL Server as the database. Unfortunately, the platform for the site hadn’t quite gotten the love and attention it deserved. On the one hand, in the words of our esteemed editor Tony “I’d consider the current platform to be a “success”; it cost $10K, has lasted for 6 years, was finished, end to end in 6 months, and although we moan about it has got us quite a long way.” On the other hand, it was becoming increasingly clear that it needed some serious work. Among other issues, we had authors that wouldn’t blog because our current blogging platform, Community Server, was too painful for them to use. Forgetting about Simple-Talk for a moment, if you ask somebody what blogging platform they’d choose, the odds are they’d say WordPress. Regardless of its technical merits, it’s probably the most popular blogging platform, and it certainly seemed easier to use than Community Server. The issue was that WordPress is normally hosted on a Linux stack running PHP, Apache and MySQL — quite a difference from our Microsoft technology stack. We certainly didn’t want to rewrite the entire site — we just wanted a better blogging platform, with the rest of the existing, legacy site left as is. At a very high level, Simple-Talk’s technical design was originally very straightforward: when your browser sends an HTTP request to Simple-Talk, IIS (the web server) takes the request, does some work, and sends back a response. In order to keep the legacy site running, except with WordPress running the blogs, a different design is called for. We now use nginx as a reverse-proxy, which can then delegate requests to the appropriate application: So, when your browser sends a request to Simple-Talk, nginx takes that request and checks which part of the site you’re trying to access. Most of the time, it just passes the request along to IIS, which can then respond in much the same way it always has. However, if your request is for the blogs, then nginx delegates the request to WordPress. Unfortunately, as simple as that diagram looks, it hides an awful lot of complexity. In particular, the legacy site running on IIS was made up of four .NET applications. I’ve already mentioned one of these applications, Community Server, which handled the old blogs as well as managing membership and the forums. We have a couple of other applications to manage both our newsletters and our articles, and our own custom application to do some of the rendering on the site, such as the front page and the articles. When I say that it was made up of four .NET applications, this might conjure up an image in your mind of how they fit together: You might imagine four .NET applications, each with their own database, communicating over well-defined APIs. Sadly, reality was a little disappointing: We had four .NET applications that all ran on the same database. Worse still, there were many queries that happily joined across tables from multiple applications, meaning that each application was heavily dependent on the exact data schema that each other application used. Add to this that many of the queries were at least dozens of lines long, and practically identical to other queries except in a few key spots, and we can see that attempting to replace one component of the system would be more than a little tricky. However, the problems with the old system do give us a good place to start thinking about desirable qualities from any changes to the platform. Specifically: Maintainability — the tight coupling between each .NET application made it difficult to update any one application without also having to make changes elsewhere Replaceability — the tight coupling also meant that replacing one component wouldn’t be straightforward, especially if it wasn’t on a similar Microsoft stack. We’d like to be able to replace different parts without having to modify the existing codebase extensively Reusability — we’d like to be able to combine the different pieces of the system in different ways for different sites Repeatable deployments — rather than having to deploy the site manually with a long list of instructions, we should be able to deploy the entire site with a single command, allowing you to create a new instance of the site easily whether on production, staging servers, test servers or your own local machine Testability — if we can deploy the site with a single command, and each part of the site is no longer dependent on the specifics of how every other part of the site works, we can begin to run automated tests against the site, and against individual parts, both to prevent regressions and to do a little test-driven development In the next part, I’ll describe the high-level architecture we now have that hopefully brings us a little closer to these five traits.

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  • OSB/OSR/OER in One Domain - QName violates loader constraints

    - by John Graves
    For demos, testing and prototyping, I wanted a single domain which contained three servers:OSB - Oracle Service BusOSR - Oracle Service RegistryOER - Oracle Enterprise Repository These three can work together to help with service governance in an enterprise.  When building out the domain, I found errors in the OSR server due to some conflicting classes from the OSB.  This wouldn't be an issue if each server was given a unique classpath setting with the node manager, but I was having the node manager use the standard startup scripts. The domain's bin/setDomainEnv.sh script has a large set of extra libraries added for OSB which look like this: if [ "${POST_CLASSPATH}" != "" ] ; then POST_CLASSPATH="${COMMON_COMPONENTS_HOME}/modules/oracle.jrf_11.1.1/jrf.jar${CLASSPATHSEP}${POST_CLASSPATH}" export POST_CLASSPATH else POST_CLASSPATH="${COMMON_COMPONENTS_HOME}/modules/oracle.jrf_11.1.1/jrf.jar" export POST_CLASSPATH fi if [ "${PRE_CLASSPATH}" != "" ] ; then PRE_CLASSPATH="${COMMON_COMPONENTS_HOME}/modules/oracle.jdbc_11.1.1/ojdbc6dms.jar${CLASSPATHSEP}${PRE_CLASSPATH}" export PRE_CLASSPATH else PRE_CLASSPATH="${COMMON_COMPONENTS_HOME}/modules/oracle.jdbc_11.1.1/ojdbc6dms.jar" export PRE_CLASSPATH fi POST_CLASSPATH="${POST_CLASSPATH}${CLASSPATHSEP}/oracle/fmwhome/Oracle_OSB1/soa/modules/oracle.soa.common.adapters_11.1.1/oracle.soa.common.adapters.jar\ ${CLASSPATHSEP}${ALSB_HOME}/lib/version.jar\ ${CLASSPATHSEP}${ALSB_HOME}/lib/alsb.jar\ ${CLASSPATHSEP}${ALSB_HOME}/3rdparty/lib/j2ssh-ant.jar\ ${CLASSPATHSEP}${ALSB_HOME}/3rdparty/lib/j2ssh-common.jar\ ${CLASSPATHSEP}${ALSB_HOME}/3rdparty/lib/j2ssh-core.jar\ ${CLASSPATHSEP}${ALSB_HOME}/3rdparty/lib/j2ssh-dameon.jar\ ${CLASSPATHSEP}${ALSB_HOME}/3rdparty/classes${CLASSPATHSEP}\ ${ALSB_HOME}/lib/external/log4j_1.2.8.jar${CLASSPATHSEP}\ ${DOMAIN_HOME}/config/osb" I didn't take the time to sort out exactly which jar was causing the problem, but I simply surrounded this block with a conditional statement: if [ "${SERVER_NAME}" == "osr_server1" ] ; then POST_CLASSPATH=""else if [ "${POST_CLASSPATH}" != "" ] ; then POST_CLASSPATH="${COMMON_COMPONENTS_HOME}/modules/oracle.jrf_11.1.1/jrf.jar${CLASSPATHSEP}${POST_CLASSPATH}" export POST_CLASSPATH else POST_CLASSPATH="${COMMON_COMPONENTS_HOME}/modules/oracle.jrf_11.1.1/jrf.jar" export POST_CLASSPATH fi if [ "${PRE_CLASSPATH}" != "" ] ; then PRE_CLASSPATH="${COMMON_COMPONENTS_HOME}/modules/oracle.jdbc_11.1.1/ojdbc6dms.jar${CLASSPATHSEP}${PRE_CLASSPATH}" export PRE_CLASSPATH else PRE_CLASSPATH="${COMMON_COMPONENTS_HOME}/modules/oracle.jdbc_11.1.1/ojdbc6dms.jar" export PRE_CLASSPATH fi POST_CLASSPATH="${POST_CLASSPATH}${CLASSPATHSEP}/oracle/fmwhome/Oracle_OSB1/soa/modules/oracle.soa.common.adapters_11.1.1/oracle.soa.common.adapters.jar\ ${CLASSPATHSEP}${ALSB_HOME}/lib/version.jar\ ${CLASSPATHSEP}${ALSB_HOME}/lib/alsb.jar\ ${CLASSPATHSEP}${ALSB_HOME}/3rdparty/lib/j2ssh-ant.jar\ ${CLASSPATHSEP}${ALSB_HOME}/3rdparty/lib/j2ssh-common.jar\ ${CLASSPATHSEP}${ALSB_HOME}/3rdparty/lib/j2ssh-core.jar\ ${CLASSPATHSEP}${ALSB_HOME}/3rdparty/lib/j2ssh-dameon.jar\ ${CLASSPATHSEP}${ALSB_HOME}/3rdparty/classes${CLASSPATHSEP}\ ${ALSB_HOME}/lib/external/log4j_1.2.8.jar${CLASSPATHSEP}\ ${DOMAIN_HOME}/config/osb" fi I could have also just done an if [ ${SERVER_NAME} = "osb_server1" ], but I would have also had to include the AdminServer because they are needed there too.  Since the oer_server1 didn't mind, I did the negative case as shown above. To help others find this post, I'm including the error that was reported in the OSR server before I made this change. ####<Mar 30, 2012 4:20:28 PM EST> <Error> <HTTP> <localhost.localdomain> <osr_server1> <[ACTIVE] ExecuteThread: '0' for queue: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <11d1def534ea1be0:30e96542:13662023753:-8000-000000000000001c> <1333084828916> <BEA-101017> <[ServletContext@470316600[app:registry module:registry.war path:/registry spec-version:null]] Root cause of ServletException. java.lang.LinkageError: Class javax/xml/namespace/QName violates loader constraints at com.idoox.wsdl.extensions.PopulatedExtensionRegistry.<init>(PopulatedExtensionRegistry.java:84) at com.idoox.wsdl.factory.WSDLFactoryImpl.newDefinition(WSDLFactoryImpl.java:61) at com.idoox.wsdl.xml.WSDLReaderImpl.parseDefinitions(WSDLReaderImpl.java:419) at com.idoox.wsdl.xml.WSDLReaderImpl.readWSDL(WSDLReaderImpl.java:309) at com.idoox.wsdl.xml.WSDLReaderImpl.readWSDL(WSDLReaderImpl.java:272) at com.idoox.wsdl.xml.WSDLReaderImpl.readWSDL(WSDLReaderImpl.java:198) at com.idoox.wsdl.util.WSDLUtil.readWSDL(WSDLUtil.java:126) at com.systinet.wasp.admin.PackageRepositoryImpl.validateServicesNamespaceAndName(PackageRepositoryImpl.java:885) at com.systinet.wasp.admin.PackageRepositoryImpl.registerPackage(PackageRepositoryImpl.java:807) at com.systinet.wasp.admin.PackageRepositoryImpl.updateDir(PackageRepositoryImpl.java:611) at com.systinet.wasp.admin.PackageRepositoryImpl.updateDir(PackageRepositoryImpl.java:643) at com.systinet.wasp.admin.PackageRepositoryImpl.update(PackageRepositoryImpl.java:553) at com.systinet.wasp.admin.PackageRepositoryImpl.init(PackageRepositoryImpl.java:242) at com.idoox.wasp.ModuleRepository.loadModules(ModuleRepository.java:198) at com.systinet.wasp.WaspImpl.boot(WaspImpl.java:383) at org.systinet.wasp.Wasp.init(Wasp.java:151) at com.systinet.transport.servlet.server.Servlet.init(Unknown Source) at weblogic.servlet.internal.StubSecurityHelper$ServletInitAction.run(StubSecurityHelper.java:283) at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321) at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:120) at weblogic.servlet.internal.StubSecurityHelper.createServlet(StubSecurityHelper.java:64) at weblogic.servlet.internal.StubLifecycleHelper.createOneInstance(StubLifecycleHelper.java:58) at weblogic.servlet.internal.StubLifecycleHelper.<init>(StubLifecycleHelper.java:48) at weblogic.servlet.internal.ServletStubImpl.prepareServlet(ServletStubImpl.java:539) at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:244) at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:184) at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.wrapRun(WebAppServletContext.java:3732) at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3696) at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321) at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:120) at weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:2273) at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:2179) at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1490) at weblogic.work.ExecuteThread.execute(ExecuteThread.java:256) at weblogic.work.ExecuteThread.run(ExecuteThread.java:221)

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  • SQL SERVER – Replace a Column Name in Multiple Stored Procedure all together

    - by pinaldave
    I receive a lot of emails every day. I try to answer each and every email and comments on Facebook and Twitter. I prefer communication on social media as this gives opportunities to others to read the questions and participate along with me. There is always some question which everyone likes to read and remember. Here is one of the questions which I received in email. I believe the same question will be there any many developers who are beginning with SQL Server. I decided to blog about it so everyone can read it and participate. “I am beginner in SQL Server. I have a very interesting situation and need your help. I am beginner to SQL Server and that is why I do not have access to the production server and I work entirely on the development server. The project I am working on is also in the infant stage as well. In product I had to create a multiple tables and every table had few columns. Later on I have written Stored Procedures using those tables. During a code review my manager has requested to change one of the column which I have used in the table. As per him the naming convention was not accurate. Now changing the columname in the table is not a big issue. I figured out that I can do it very quickly either using T-SQL script or SQL Server Management Studio. The real problem is that I have used this column in nearly 50+ stored procedure. This looks like a very mechanical task. I believe I can go and change it in nearly 50+ stored procedure but is there a better solution I can use. Someone suggested that I should just go ahead and find the text in system table and update it there. Is that safe solution? If not, what is your solution. In simple words, How to replace a column name in multiple stored procedure efficiently and quickly? Please help me here with keeping my experience and non-production server in mind.” Well, I found this question very interesting. Honestly I would have preferred if this question was asked on my social media handles (Facebook and Twitter) as I am very active there and quite often before I reach there other experts have already answered this question. Anyway I am now answering the same question on the blog so all of us can participate here and come up with an appropriate answer. Here is my answer - “My Friend, I do not advice to touch system table. Please do not go that route. It can be dangerous and not appropriate. The issue which you faced today is what I used to face in early career as well I still face it often. There are two sets of argument I have observed – there are people who see no value in the name of the object and name objects like obj1, obj2 etc. There are sets of people who carefully chose the name of the object where object name is self-explanatory and almost tells a story. I am not here to take any side in this blog post – so let me go to a quick solution for your problem. Note: Following should not be directly practiced on Production Server. It should be properly tested on development server and once it is validated they should be pushed to your production server with your existing deployment practice. The answer is here assuming you have regular stored procedures and you are working on the Development NON Production Server. Go to Server Note >> Databases >> DatabaseName >> Programmability >> Stored Procedure Now make sure that Object Explorer Details are open (if not open it by clicking F7). You will see the list of all the stored procedures there. Now you will see a list of all the stored procedures on the right side list. Select either all of them or the one which you believe are relevant to your query. Now… Right click on the stored procedures >> SELECT DROP and CREATE to >> Now select New Query Editor Window or Clipboard. Paste the complete script to a new window if you have selected Clipboard option. Now press Control+H which will bring up the Find and Replace Screen. In this screen insert the column to be replaced in the “Find What”box and new column name into “Replace With” box. Now execute the whole script. As we have selected DROP and CREATE to, it will created drop the old procedure and create the new one. Another method would do all the same procedure but instead of DROP and CREATE manually replace the CREATE word with ALTER world. There is a small advantage in doing this is that if due to any reason the error comes up which prevents the new stored procedure to be created you will have your old stored procedure in the system as it is. “ Well, this was my answer to the question which I have received. Do you see any other workaround or solution? Reference : Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Server Management Studio, SQL Stored Procedure, SQL Tips and Tricks, T SQL, Technology

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