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• USB and CD data cannot be read or mounted in 12.10

  - by aravind4j

  I'm using Ubuntu 12.10. I wrote a data disk using Brasero Disk Burner, but the system cannot read the CD. I tried to write the same data into my HP v220w pen drive but now there is an error in that too. It shows the following: Error mounting /dev/sdb at /media/aravind4j/Aravind4j: Command-line `mount -t "ntfs" -o "uhelper=udisks2,nodev,nosuid,uid=1000,gid=1000,dmask=0077,fmask=0177" "/dev/sdb" "/media/aravind4j/Aravind4j"' exited with non-zero exit status 13: $MFTMirr does not match $MFT (record 0). Failed to mount '/dev/sdb': Input/output error NTFS is either inconsistent, or there is a hardware fault, or it's a SoftRAID/FakeRAID hardware. In the first case run chkdsk /f on Windows then reboot into Windows twice. The usage of the /f parameter is very important! If the device is a SoftRAID/FakeRAID then first activate it and mount a different device under the /dev/mapper/ directory, (e.g. /dev/mapper/nvidia_eahaabcc1). Please see the 'dmraid' documentation for more details. (udisks-error-quark, 0) I used a NTFS file system for the pen drive as you can recognize from the above statement. I would like to recover the files so please help me recover the files without formatting the drive.

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• Are the only types of data "sources" static and dynamic?

  - by blunders

  Thinking that there might be others, but not sure -- but before getting into that, let me explain what I mean by static and dynamic data sources. Static (or datastore) - Meaning that the data's state is non-changing, and if was changed, that would be a new state, and the old data would be considered stateless; meaning it no longer is known to exist, or not exist. Another way of possibly looking at a static data source might be that if read and written back without modification, the checksum for before and after should be exactly the same regardless of the duration of time between the reading and rewriting of the data. Examples: Photos, Files, Database Record, Dynamic (or datastream) - Meaning that the data's state is known to be in flux, and never expected to be the same per input. Example: Live video/audio feed, Stock Market feed, First let me say, the above is a very loose mapping of the concepts, and I'd welcome any feedback. Next, onto the core of the question, that being are these the only two types of data sources. My guess, is that yes, they are -- but that there are hybrid versions of the two. That being, streaming data that has a fixed state. For example, the data being streamed has a checksum given and each unique checksum is known to be a single instance of static data. On the flip side, static data could be chained via say a version control system; when played back, each version might be viewed as a segment of a stream; thing is, the very fact that it can be played back makes the data source static. Another type might be that the data source is being organically discovered, and it's simply unknown what the state is. Questions, feedback, requests -- just comment, thanks!!

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• NoSQL

  - by NoReasoning

  Last night, (Tuesday, June 28), at the KC .NET User group meeting, George Westwater gave a terrific presentation on NoSQL. The best way to define it (the best way is to see George explain it, and he says he will record his presentation and make it available through his blog – link above)  is databases  that does not use relational technology. And his point, and this is true – I have been around awhile – is that non-relational databases have been used for over 50 years in the business. He points out that Wall Street firms have been using non-relational technology ever since they started using computers. IBM still fully supports IMS, now in version 11 (12 is in beta), because these firms are still using this product and will continue to do so for a long time. Of course, like a lot of computer business technology, there are a lot of new NoSQL products available these days, simply as a reaction to the problems of scaling relational databases for internet use. As a result, it almost looks as though NoSQL is something new. And there are a lot, I mean a LOT, I mean a L-O-T , of new products out there for this technology. The best resource to cover all of these products is http://nosql-database.org/, which has a huge listing of what is available. My interest in the subject is primarily due to my interest in Windows Azure and the fact that Windows Azure storage is all non-relational, even the table storage. It is very fascinating and most of all, far cheaper than using SQL Azure for storage in the “cloud."

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• Turning a problem into a data

  - by Fogmeister

  OK, I have an app that I'm creating but I'm just really not sure about how to approach the problem. The idea is fairly simple. I'm just not sure how to wrap it in a data model (or even if I should). TBH I feel like I'm making it more complicated than it needs to be. How it works. The app will have circles along the top in a row that need to be connected to circles along the bottom in a row. 10 circles at the top. 10 at the bottom. One connection per pair of dots. Anyway, I can get the dots to connect I'm just not sure how to wrap it in a data model so that I can analyse what has been connected and see if it is right or not. The circles will be questions and answers. I can make an array of question objects with a question and answer properties. I can then display these as the dot pairs. I'm just not sure how to record which questions have been connected to which answers. It is valid for a user to connect a wrong answer as they all get checked at the end. I was thinking of using SpriteKit but this isn't a restriction. I could use UIKit or something else. TBH, this question is fairly language free as I'm just after a way of modelling it.

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• Sitecore Item Web API and Json.Net Test Drive (Part II –Strongly Typed)

  - by jonel

  In the earlier post I did related to this topic, I have talked about using Json.Net to consume the result of Sitecore Item Web API. In that post, I have used the keyword dynamic to express my intention of consuming the returned json of the API. In this article, I will create some useful classes to write our implementation of consuming the API using strongly-typed. We will start of with the Record class which will hold the top most elements the API will present us. Pretty straight forward class. It has 2 properties to hold the statuscode and the result elements. If you intend to use a different property name in your class from the json property, you can do so by passing a string literal of the json property name to the JsonProperty attribute and name your class property differently. If you look at the earlier post, you will notice that the API returns an array of items that contains all of the Sitecore content item or items and stores them under the result->items array element. To be able to map that array of items, we have to write a collection property and decorate that with the JsonProperty attribute. The JsonItem class is a simple class which will map to the corresponding item property contained in the array. If you notice, these properties are just the basic Sitecore fields. And here’s the main portion of this post that will binds them all together. And here’s the output of this code. In closing, the same result can be achieved using the dynamic keyword or defining classes to map the json propery returned by the Sitecore Item Web API. With a little bit more of coding, you can take advantage of power of strongly-typed solution. Have a good week ahead of you.

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• Best Architecture for ASP.NET WebForms Application

  - by stack man

  I have written an ASP.NET WebForms portal for a client. The project has kind of evolved rather than being properly planned and structured from the beginning. Consequently, all the code is mashed together within the same project and without any layers. The client is now happy with the functionality, so I would like to refactor the code such that I will be confident about releasing the project. As there seems to be many differing ways to design the architecture, I would like some opinions about the best approach to take. FUNCTIONALITY The portal allows administrators to configure HTML templates. Other associated "partners" will be able to display these templates by adding IFrame code to their site. Within these templates, customers can register and purchase products. An API has been implemented using WCF allowing external companies to interface with the system also. An Admin section allows Administrators to configure various functionality and view reports for each partner. The system sends out invoices and email notifications to customers. CURRENT ARCHITECTURE It is currently using EF4 to read/write to the database. The EF objects are used directly within the aspx files. This has facilitated rapid development while I have been writing the site but it is probably unacceptable to keep it like that as it is tightly coupling the db with the UI. Specific business logic has been added to partial classes of the EF objects. QUESTIONS The goal of refactoring will be to make the site scalable, easily maintainable and secure. 1) What kind of architecture would be best for this? Please describe what should be in each layer, whether I should use DTO's / POCO / Active Record pattern etc. 2) Is there a robust way to auto-generate DTO's / BOs so that any future enhancements will be simple to implement despite the extra layers? 3) Would it be beneficial to convert the project from WebForms to MVC?

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• invitation: Oracle Endeca Information Discovery Bootcamp

  - by mseika

  The Oracle Endeca Information Discovery (OEID) Boot Camp is designed to give partners an understanding of OEID’s features, and how it complements the existing Oracle Business Intelligence suite. Participants will learn how to develop & implement solutions using a Data Discovery method. Training is in EnglishWhat will be covered?The Oracle Endeca Information Discovery (OEID) Boot Camp is a three-day class with a combination of lecture and hands-on exercises, tailored to make participants aware of the Oracle Endeca Information Discovery platform, and to gain valuable skills for the implementation of projects.The course will follow a combination of lectures and hands-on lab sessions, to allow participants to apply the knowledge they have gained by extracting from sample data sources, and creating an end-user application that will be used to answer several business questions. What You Will Learn Architecture: OEID Components, use of graphs, overview of clustering OEID Installation: Architecture planning, infrastructure requirements, installation process, production hints & tips OEID Administration: Data store management, administrative operations, portal configuration, data sources, system monitoring Indexing: Integration Suite, Data source analysis, Graph (ETL) creation, record design techniques Portlets: Studio portlets, custom portlet development, querying functions Reporting: Studio applications & best practices, visualizations, EQL PrerequisitesYou must bring a laptop with you for the Hands-on labs ENVIRONMENT – LAPTOP REQUIREMENTS For the OEID boot camp, participants will perform the hands-on lab exercises using a virtual machine image. These virtual machines will be provided to participants within a cloud environment, requiring participants to bring a laptop to the Boot Camp that can access a Windows server utilizing Microsoft RDP from their laptop. Participants will not need to install any software onto their laptops, but must ensure that they have the proper software installed for their OS, to connect through RDP to a server. HARDWARE • CPU: Dual-core, x64, 1.8Ghz or higher • RAM: 2GB SOFTWARE • Microsoft Remote Desktop Client • Internet Explorer 7, Firefox, or Google Chrome This boot camp is intended for prospective implementers of Oracle Endeca Information Discovery (OEID), or those in a presales role looking to gain insight into the technical benefits of this new package. Attendees should have experience and familiarity with the basic concepts of business intelligence. Where and When ? Monday, October 15th until wednesday, October 17th included 9:00 - 18:00 Oracle France 15, boulevard Charles de Gaulle 92715 Colombes Access Register Here Limited number of seats !

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• Pidgin XML

  - by David Totzke

  I'm looking at an xml document that gets passed to a COM object (yes, I said the "C" word) to save a new record.  You can tell by the "new|" at the top of the file before the xml declaration.  If we were saving, there would be "edit|" at the top.  Couldn't you just have a root element with something like: <myRootElement mode="new"> Ah, here's why that won't work... There's no single root element but that's ok because next we find that this document is actually several documents.  <?xml version="1.0"?> appears several times.  The final document opens with <myElementStart> and closes with <myElementEnd> so it's not even well-formed. This isn't a style thing.  This is broken.  I mean, basic well-formed XML only has two rules; three if you count the xml declaration but it works as a document for DTO purposes without it. One root element. Close all elements with a matching tag. As a result, both ends of this conversation need to speak the same dialect of broken XML in order to communicate.  To join the conversation, you must also learn pidgin XML. How can you start out so right - XML being the obvious choice in this instance - and then go so horribly wrong? Dave Just because I can…

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• Why can't tuxboot and ubuntu play well together?

  - by mmr

  I'm trying to get clonezilla to run off of a usb stick, and it seems that the right way to do that is via tuxboot. Tuxboot is not compilable on ubuntu. I used git to get it from the repository, and then when I run the 'install' script (because building it is apparently not allowed, since the build script just tries to install windows things). Qmake-linux wants my qmake executable to be in the same directory as the stuff I pulled down, and let's just say that if there's a way to do this easily, I ain't seein' it. So then I download the linux file, the most recent of which is tuxboot-linux-25. Try to run it, get a failure that libpng12.so.0 isn't found. OK, then I go to install that via the instructions I found on the web but firefox seems to have already deleted from my history (yay!) Then I add the /usr/local/lib directory to ldconfig via emacs (had to install that too, of course): http://ubuntuforums.org/showthread.php?t=369848 I still get the errors that libpng12.so.0 cannot be opened because 'No such file or directory'. ldconfig -p | grep libpng shows that the library is there, but it still doesn't seem to be findable. What to do next? (for the record, doing this in windows is painless-- download, click, and it's done. But I'm trying to be all linuxy and get away from Windows for this...)

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• What's the proper term for a function inverse to a constructor - to unwrap a value from a data type?

  - by Petr Pudlák

  Edit: I'm rephrasing the question a bit. Apparently I caused some confusion because I didn't realize that the term destructor is used in OOP for something quite different - it's a function invoked when an object is being destroyed. In functional programming we (try to) avoid mutable state so there is no such equivalent to it. (I added the proper tag to the question.) Instead, I've seen that the record field for unwrapping a value (especially for single-valued data types such as newtypes) is sometimes called destructor or perhaps deconstructor. For example, let's have (in Haskell): newtype Wrap = Wrap { unwrap :: Int } Here Wrap is the constructor and unwrap is what? The questions are: How do we call unwrap in functional programming? Deconstructor? Destructor? Or by some other term? And to clarify, is this/other terminology applicable to other functional languages, or is it used just in the Haskell? Perhaps also, is there any terminology for this in general, in non-functional languages? I've seen both terms, for example: ... Most often, one supplies smart constructors and destructors for these to ease working with them. ... at Haskell wiki, or ... The general theme here is to fuse constructor - deconstructor pairs like ... at Haskell wikibook (here it's probably meant in a bit more general sense), or newtype DList a = DL { unDL :: [a] -> [a] } The unDL function is our deconstructor, which removes the DL constructor. ... in The Real World Haskell.

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• Help parsing long (3.5mil lines) text file, line by line and storing data, need a strategy

  - by Jarrod

  This is a question about solving a particular problem I am struggling with, I am parsing a long list of text data, line by line for a business app in PHP (cron script on the CLI). The file follows the format: HD: Some text here {text here too} DC: A description here DC: the description continues here DC: and it ends here. DT: 2012-08-01 HD: Next header here {supplemental text} ... this repeats over and over for a few hundred megs I have to read each line, parse out the HD: line and grab the text on this line. I then compare this text against data stored in a database. When a match is found, I want to then record the following DC: lines that succeed the matched HD:. Pseudo code: while ( the_file_pointer_isnt_end_of_file) { line = getCurrentLineFromFile title = parseTitleFrom(line) matched = searchForMatchInDB(line) if ( matched ) { recordTheDCLines // <- Best way to do this? } } My problem is that because I am reading line by line, what is the best way to trigger the script to start saving DC lines, and then when they are finished save them to the database? I have a vague idea, but have yet to properly implement it. I would love to hear the communities ideas\suggestions! Thank you.

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• 12.10 upgrade broke brightness keys [closed]

  - by Chris Morgan

  I have been running Ubuntu (64-bit) on my HP 6710b laptop (Core 2 Duo with integrated graphics) for several years, and the backlight brightness keys have always worked. Since I upgraded to Ubuntu 12.10 earlier today, those keys do not work any more. The secondary function keys: Fn+F3: sleep; still works (and considerably faster than ever before!) Fn+F8: battery info; still works Fn+F9: reduce brightness; stopped working in 12.10 Fn+F10: increase brightness; stopped working in 12.10 It may also be worth while mentioning that X does not appear to be receiving the brightness events at all, or at least not sending them out further. (This I detected with a key logger I wrote for a Uni project, which uses X's Record extension; it is informed of the sleep and battery info keystrokes, but doesn't receive the brightness ones at all.) In the mean time, I know that I can use the Brightness & Lock settings screen to alter the brightness. (Wow! I can suddenly make my backlight darker than I could before—I can go right down to turning the backlight off, something I couldn't do before... but this model has a fairly dim screen, so I don't expect to use that much, if ever.) How can I get the brightness keys working again? This question is probably strongly related to I can't control my Brightness in HP Compaq 6710s.

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• Ensure Payroll Success with PeopleSoft Year-End Training for U.S. and Canada

  - by Breanne Cooley

  Year-end payroll processing and reporting is a requirement for your business. If you're responsible for completing these processes in either Canada or the United States using the PeopleSoft Payroll application, and if you're new to PeopleSoft Payroll or to performing these processes, consider enrolling in Oracle University's expert training. Our PeopleSoft Payroll specialists will guide you through the necessary steps to ensure you can smoothly and successfully perform your job. Training is specific to the country for which you are performing the processing and reporting. Training lasts one day and is delivered in our Live Virtual Class Format, which helps you avoid travel during this busy season. Here's the training we recommend: PeopleSoft Year-End Payroll - U.S. This course teaches you how to complete U.S. year-end processing and reporting using PeopleSoft Payroll for North America, step-by-step. Update tax reporting setup tables and update employees' income and tax records. Load each employee's year-end data into a single year-end record for processing and reporting.  Identify reports needed to reconcile the year-end data. Correct tax balances and other data as necessary. Generate final print and online W-2 forms and prepare the electronic file for the Social Security Administration.  Enter corrected W-2 information and print a W-2c form. Report periodic retirement distributions and related tax withholding amounts on form 1099-R.   Please Note: this course is intended for organizations using PeopleSoft release 8.81 or higher. PeopleSoft Year-End Payroll – Canada This course covers the steps necessary to perform Canadian year-end processing using Oracle's PeopleSoft Payroll for North America. Explore adjustments, balances, year-end slip processing, common pitfalls and errors and balancing reports.  Produce accurate year-end reporting results such as T4, T4A, RL-1 and RL-2.  Please Note: this course is intended for organizations using PeopleSoft release 8.81 or higher. See you in class! -Oracle University Marketing Team 

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• Deploy multiple emails to email providers, but without showing favouritism

  - by Ardman

  We are currently developing a new email deployment system. We have the system currently configured so that it reads a record from the database and loads the email content and deploys it to the target. Now we want to move this over to multiple threads. That is easily done, except we then hit the email providers returning SMTP codes referring to "Too many connections", or "Deferred connection". The solution to this is to have a thread open up a connection to the email provider and deploy n emails and then disconnect. We have currently configured the application so that it will support these session based email deployments. The problem is this, the database table has multiple email addresses in and they aren't grouped by email provider because that will show favouritism. We need to be able to retrieve a set number of, i.e. Hotmail, emails (@hotmail.com, @hotmail.co.uk, @live.co.uk) so that we are reducing the number of connections to Hotmail and reducing the risks of getting the "Too many connections" error. We are at the point now where we have gone round and round in circles trying to get a solution, so I thought I'd throw it out there and see if anyone has any ideas? EDIT I would like to stress that this application is not used for spamming purposes.

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• How do you determine whether a website is a scam [closed]

  - by Tom

  What's the best way to determine if a website is a scam. For example, at first sight (no pun intended) the following website seems to be legitimate. But the price of the product is suspiciously low (all the reviews point to an RRP of approximately £1000). http://www.maxiargos.com/index.php/asus-zenbook-ux31e-dh72-13-3-inch-thin-and-light-ultrabook-silver-aluminum.html Another indication is the lack of SSL for the checkout page, and lack of useful information in the WHOIS record. Registration Service Provided By: TMDHOSTING Contact: +1.8665325635 Domain Name: MAXIARGOS.COM Registrant: PrivacyProtect.org Domain Admin ([email protected]) ID#10760, PO Box 16 Note - All Postal Mails Rejected, visit Privacyprotect.org Nobby Beach null,QLD 4218 AU Tel. +45.36946676 Creation Date: 09-Nov-2011 Expiration Date: 09-Nov-2012 Domain servers in listed order: ns1.tmdhosting410.com ns2.tmdhosting410.com Administrative Contact: PrivacyProtect.org Domain Admin ([email protected]) ID#10760, PO Box 16 Note - All Postal Mails Rejected, visit Privacyprotect.org Nobby Beach null,QLD 4218 AU Tel. +45.36946676 Technical Contact: PrivacyProtect.org Domain Admin ([email protected]) ID#10760, PO Box 16 Note - All Postal Mails Rejected, visit Privacyprotect.org Nobby Beach null,QLD 4218 AU Tel. +45.36946676 Billing Contact: PrivacyProtect.org Domain Admin ([email protected]) ID#10760, PO Box 16 Note - All Postal Mails Rejected, visit Privacyprotect.org Nobby Beach null,QLD 4218 AU Tel. +45.36946676

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• New XAML-Based User Group started in Birmingham, Alabama.

  - by mbcrump

  I’m pleased to announce that a new XAML-Based User Group has started in Birmingham, Alabama. The group is being hosted by Michael Crump and Jonathan Marbutt. The reason is very simple: we feel that Birmingham needs a fresh start. We are both very passionate about .NET and are hoping to share our experiences with the community. We have created a site (http://allaboutxaml.net) and our first meetup is now scheduled. We are here to discuss all things that have to do with xaml. This includes Silverlight, WPF, Windows Phone 7, Surface, Lightswitch and Silverlight with SharePoint 2010. We: believe strongly in xaml and are passionate about what we talk about. believe in an open-forum. believe a user group should be FUN as well as educational. do not claim to be an expert on anything, we are here to share. record every presentation and put it on the web for others to benefit. meet monthly but are flexible on the actual date. do our events outside of technical colleges. have families and our meetings start and stop on time. welcome new speakers. welcome adult beverages. Our first meeting is going to be on February 15th, 2011 (6PM), at Logan's on HWY 280. It is going to be more of a meetup than a meeting. I would like to discuss current xaml-based projects that you are working on and get to know one another. If you are interested in coming then please sign up here so that we know how many to expect. Please visit our site to find out more about us: http://allaboutxaml.net.

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• Algorithm to match timestamped events from two sources

  - by urza.cc

  I have two different physical devices (one is camera, one is other device) that observe the same scene and mark when a specified event occures. (record timestamp) So they each produce a serie of timestamps "when the event was observed". Theoretically the recorded timestamps should be very well aligned: Visualized ideal situation on two time lines "s" and "r" as recorded from the two devices: but more likely they will not be so nicely aligned and there might be missing events from timeline s or r: I am looking for algorithm to match events from "s" and "r" like this: So that the result will be something like: (s1,null); (s2,r1); (s3,null); (s4,r2); (s5,r3); (null,r4); (s6,r5); Or something similar. Maybe with some "confidence" rating. I have some ideas, but I feel that this might be probably a well known problem, that has some good known solutions, but I don't know the right terminology. I am a little bit out of my element here, this is not my primary area of programming.. Any helps, suggestions etc will be appreciated.

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• Possible to draw a select portion of a render target? (in XNA)

  - by TheBroodian

  I'm going to try to do this in reverse fashion and skip straight to the punch line, and then give the back story afterward: Is it possible to, after drawing a scene to a RenderTarget2D, only draw a select portion of the RenderTarget2D, if I don't want the entire thing? I'm using xTile to manage world data in my game (it's a great piece of work, colinvella [xTile's author] has made an amazing product), and for the most part it works great. xTile supports parallax effects in its layers to add some wonderful depth to 2d scenes, which was great, until I implemented a dynamic split-screen system into my game. Wanted to make a co-op game that wouldn't require players to be in close proximity to each other, so I made it so that if the players separate too far apart, the singular full-screen viewport 'snaps-apart', and is replaced by two split-screen viewports, which then smoothly transition to their respective player targets. The effect is pretty smooth aside from the part where the parallax backgrounds become skewed once the viewports split, because xTile's ratio for handling parallax effects is dependent upon viewport size. This is unfortunate, because the effect would otherwise be really snazzy, but the backgrounds become pretty heavily affected when the game goes from single-viewport to multi-viewport. So, Colinvella suggests using rendertargets to record the scene at full viewport size, and then only drawing a portion of it. But as far as I can tell, that isn't even possible? That being said, I've never even used render targets before, so I'm still learning, hence the question here.

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• Flow Fields in Dynamics NAV

  - by T

  I don’t know the exact business reason but someone asked how to identify all sales shipping orders with any negative quantities on them.  They needed to print these separately from the shipments that only have all positive quantities. Here is one way to solve this problem In NAV, open Sales Shipment Header Add a field of type Boolean (The field type should match the value you expect to return from the flow field method.  In this case we will use an exist so we expect a bool but we could have used a Sum, Average, Min, Max, Count, or a Lookup to return a value). Define it as a flow field and click on the ellipse next to CalcFormula Now [Has Negative Qty] is false if no negatives exist And [Has Negative Qty] and true if a negative exist So it is ready to be used as a filter on the report. Don’t forget that if you are using it in code, you may need to CalcFields. Hope that helps.  If you really can’t afford the field in your header, you can use code to check the lines for a negative value each time and use a skip or break function to skip that header record but it seems expensive to check them all if you only want a few to print. Please let me know if you think of a better solution.

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• Is there a canonical source supporting "all-surrogates"?

  - by user61852

  Background The "all-PK-must-be-surrogates" approach is not present in Codd's Relational Model or any SQL Standard (ANSI, ISO or other). Canonical books seems to elude this restrictions too. Oracle's own data dictionary scheme uses natural keys in some tables and surrogate keys in other tables. I mention this because these people must know a thing or two about RDBMS design. PPDM (Professional Petroleum Data Management Association) recommend the same canonical books do: Use surrogate keys as primary keys when: There are no natural or business keys Natural or business keys are bad ( change often ) The value of natural or business key is not known at the time of inserting record Multicolumn natural keys ( usually several FK ) exceed three columns, which makes joins too verbose. Also I have not found canonical source that says natural keys need to be immutable. All I find is that they need to be very estable, i.e need to be changed only in very rare ocassions, if ever. I mention PPDM because these people must know a thing or two about RDBMS design too. The origins of the "all-surrogates" approach seems to come from recommendations from some ORM frameworks. It's true that the approach allows for rapid database modeling by not having to do much business analysis, but at the expense of maintainability and readability of the SQL code. Much prevision is made for something that may or may not happen in the future ( the natural PK changed so we will have to use the RDBMS cascade update funtionality ) at the expense of day-to-day task like having to join more tables in every query and having to write code for importing data between databases, an otherwise very strightfoward procedure (due to the need to avoid PK colisions and having to create stage/equivalence tables beforehand ). Other argument is that indexes based on integers are faster, but that has to be supported with benchmarks. Obviously, long, varying varchars are not good for PK. But indexes based on short, fix-length varchar are almost as fast as integers. The questions - Is there any canonical source that supports the "all-PK-must-be-surrogates" approach ? - Has Codd's relational model been superceded by a newer relational model ?

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• Visual Studio 2012 first impressions...no Macros!

  - by bconlon

  Yesterday I installed Microsoft Visual Studio 2012 for the first time (all 8.5GB) and after 20 years of (mostly) happy times using VS they have removed Macros, one of the most handy features.The first thing I wanted to do when I upgraded my VS2010 project was to add a #elseif block to each file. This would usually be simple case of find in files of the previous #elseif and then Ctrl+Shift+R to record a macro which would be: F8 (to select the next file from find list), F3 (to find the correct position in file), Ctrl+V to paste the new code. Then all I would need to do is keep Ctrl+Shift+P (Play Macro) pressed until all the files were processed.But alas Ctrl+Shift+R does nothing! I won’t say that I use Macros every day but it was a very useful feature.To continue my moaning a little more, I also don't like the bland interface. This has been well documented by others, but now I have used it myself, I find it difficult to tell one grey area of screen from another and the lack of colour makes the icons unclear.I also don't see why the menus now need to SHOUT in capital letters?On the plus side, they have now added the ability to see WPF properties in the debugger...a bit of an oversight in Visual Studio 2010. Oh, but you still can't edit and continue on files that contain templated code.Whilst Visual Studio 2012 is not a complete disaster like Windows 8 (why develop a desk top OS to be the same as a Smart device OS), it does not float my boat.Rant over.#

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• How to Structure a Trinary state in DB and Application

  - by ABMagil

  How should I structure, in the DB especially, but also in the application, a trinary state? For instance, I have user feedback records which need to be reviewed before they are presented to the general public. This means a feedback reviewer must see the unreviewed feedback, then approve or reject them. I can think of a couple ways to represent this: Two boolean flags: Seen/Unseen and Approved/Rejected. This is the simplest and probably the smallest database solution (presumably boolean fields are simple bits). The downside is that there are really only three states I care about (unseen/approved/rejected) and this creates four states, including one I don't care about (a record which is seen but not approved or rejected is essentially unseen). String column in the DB with constants/enum in application. Using Rating::APPROVED_STATE within the application and letting it equal whatever it wants in the DB. This is a larger column in the db and I'm concerned about doing string comparisons whenever I need these records. Perhaps mitigatable with an index? Single boolean column, but allow nulls. A true is approved, a false is rejected. A null is unseen. Not sure the pros/cons of this solution. What are the rules I should use to guide my choice? I'm already thinking in terms of DB size and the cost of finding records based on state, as well as the readability of code the ends up using this structure.

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• My game seems to be incompatible with recording software. What could be causing this?

  - by Lewis Wakeford

  I've just finished a little Game-Dev project for university and I need to record a video to accompany my submission (just in case they can't get my source to work). Basically my game doesn't work at all when FRAPS or Bandicam attempts to attach to it, I get a black screen and a stream of GL INVALID OPERATION messages from my error reporting code. Dxtory can't seem to hook into it correctly at all, it doesn't display it's FPS counter or anything. My game logic appears to be running correctly from the debug traces, it just seems like all the gl library calls break. I don't know a huge amount about how these programs operate so I don't really know what I could be doing to cause this. I've heard they read from the OpenGL frame buffers so maybe I'm doing something wrong there? I'm letting GLFW and GLEW do all the low level initialization, but I have successfully recorded projects with the same setup and recording software. Essentially, has anyone ever run into something like this before or do you know anything about how these programs work that could give a clue as to the cause of the issue?

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• Designing and refactoring of payment logic

  - by jokklan

  Im currently working on an application that helps users to coordinate dinner clubs and all related accounting. (A dinner club is where people in a group, take turns to cook for the rest and then you pay a small amount to participate. This is pretty normal in dorms and colleges where im from). However there is some different models that all have a price and the accounting aspect is therefore a little spread. We both have DinnerClub, ShoppingItem and are about to implement the third Payment when users pay their debts (or get refunded for expenses). Each of these have a "price" attribute and a users expense (that he or she needs refunded) is calculated by the total of these "prices" minus what other users have bought and he or she have used/participated in. My question is then if someone have some hints to refactor this bring all this behavior together in one place? For now have i thought about a Transaction class that are responsible for this behaviour, but I'm a little worried about the performance impact on having to query for another polymorphic record each time i want to show the price on dinner clubs and shopping items (i have a standard index page with a list for both so it's a lot of extra records being queried)...

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• Thoughts on exception handling.

  - by AndyScott

  Was working on a windows form app (something I haven't done in a while), adding threading and logging so that it would work a little more smoothly and have a record of who did what.  I was just about at the point where I was going to check it into source control when I noticed that the Output window was showing "A first chance exception of type 'System.InvalidCastException' occurred in mscorlib.dll", so I googled it.  In reading some threads about the error, I came across the following comment and it got me thinking: "In addition, while they should be avoided if possible, exceptions are a quite legitimate part of program execution. It's their going unhandled that is a real issue, because that means crashy, crashy." How do you normally use exception handling?  I feel that exceptions are intended to handle errors in code (in my experience generally related to bad data making its way into the system).  Now don't get me wrong, I understand that exceptions happen and should be dealt with, but I feel that they are a "last resort" to keep a program from crashing, but should never be a way to pass data or continue logical processing that could be handled in standard code flow. I mention this, because I have seen it done. What do you think?

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