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  • google custom search gives different result number for same query

    - by santiagozky
    We are using google custom search and we have found that often the totalResults iterates between two values, even for the same query. The different values can be slightly different or more than double. The parameters I am using look like this: https://www.googleapis.com/customsearch/v1? q=something cx=XXXXXXXXXX lr=lang_en siteSearch=www.mydomain.com start=1 fields=context%2Citems%28fileFormat%2CformattedUrl%2Clink%2Cpagemap%2Csnippet%2Ctitle%29%2Cqueries%2CsearchInformation%28searchTime%2CtotalResults%29%2Cspelling%2FcorrectedQuery key=YYYYYYYYYYYYYYY filter=0 This is problem because of calculating the number of result pages. How can I get the same results for the same query?

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  • How should I make searching a relational database more efficient?

    - by Travis J
    This is in the scope of a web application. I have a database which has a few nested relations. There is a feature which depicts the history of a large chain of relations. It is essentially a data analysis feature. The issue is that in order to search, a large object graph must be loaded - the loading time for this object graph is not quick enough to be viable. The problem is that without loading the whole graph it makes searching from a single string nearly impossible. In order to search, explicit fields must be specified and the search data supplied. Is there a design pattern for exposing the data in a way which facilitates a single string search instead of having to explicitly define parameters?

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  • Scala factory pattern returns unusable abstract type

    - by GGGforce
    Please let me know how to make the following bit of code work as intended. The problem is that the Scala compiler doesn't understand that my factory is returning a concrete class, so my object can't be used later. Can TypeTags or type parameters help? Or do I need to refactor the code some other way? I'm (obviously) new to Scala. trait Animal trait DomesticatedAnimal extends Animal trait Pet extends DomesticatedAnimal {var name: String = _} class Wolf extends Animal class Cow extends DomesticatedAnimal class Dog extends Pet object Animal { def apply(aType: String) = { aType match { case "wolf" => new Wolf case "cow" => new Cow case "dog" => new Dog } } } def name(a: Pet, name: String) { a.name = name println(a +"'s name is: " + a.name) } val d = Animal("dog") name(d, "fred") The last line of code fails because the compiler thinks d is an Animal, not a Dog.

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  • SQLAuthority News – Windows Azure Training Kit Updated October 2012

    - by pinaldave
    Microsoft has recently released the updated to Windows Azure Training Kit. Earlier this month they have updated the kit and included quite a lot of things. Now the training kit contains 47 hands-on labs, 24 demos and 38 presentations. The best part is that the kit is now available to download in two different formats 1) Full Package (324.5 MB) and 2) Web Installer (2.4 MB). The full package enables you to download all of the hands-on labs and presentations to your local machine. The Web Installer allows you to select and download just the specific hands-on labs and presentations that you need. This Windows Azure Training Kit contains Hands on Labs, Presentations and Videos and Demos. I encourage all of you to try this out as well. The Kit also contains details about Samples and Tools. The training kit is the most authoritative learning resource on Windows Azure. You can download the Windows Azure Training Kit from here. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Azure, SQL Download, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Using Java classes in JRuby

    - by kerry
    I needed to do some reflection today so I fired up interactive JRuby (jirb) to inspect a jar.  Surprisingly, I couldn’t remember exactly how to use Java classes in JRuby.  So I did some searching on the internet and found this to be a common question with many answers.  So I figure I will document it here in case I forget how in the future. Add it’s folder to the load path, require it, then use it! $: << '/path/to/my/jars/' require 'myjar' # so we don't have to reference it absolutely every time (optional) include Java::com.goodercode my_object = SomeClass.new

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  • Oracle Applications Guidance for Exalogic

    - by james.bayer
    Exalogic is continuing to help Oracle deliver on the tagline “Hardware and Software – Engineered to Work Together”.  My Oracle Support article ID 1302529.1 was just posted and enumerates various Oracle Applications versions that are recommended for deployment on Exalogic.  Please access the note via My Oracle Support for the details.  These applications currently include: Oracle Applications such as E-Business Suite, Siebel, PeopleSoft Enterprise, and JD Edwards EnterpriseOne Utilities Applications including Mobile Workforce Management, Meter Data Management, and Customer Care and Billing Oracle Retail Applications Merchandising Operations Management and Merchandising Planning & Optimization modules The reference video below offers a great explanation for how Exalogic can be an ideal platform for Oracle software including Oracle Applications.

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  • Is LightDM is broken? Autologin works

    - by Ben
    I recently upgraded my Mythbuntu box to 11.10. LightDM worked for a while and then I configured autologin on my user account. After some time, I've removed some packages to lean down the system. Now when I log out (from either Unity or Gnome Shell) I lose the X session, LightDM doesn't start back up. If I disable autologin through /etc/lightdm/lightdm.conf I get no login screen & no X. As I said, autologin works and gives me a Ubuntu Classic desktop. This is the only reference in dmesg to lightdm; [ 17.351023] type=1400 audit(1329530135.420:19): apparmor="STATUS" operation="profile_load" name="/usr/lib/lightdm/lightdm-guest-session-wrapper" pid=1097 comm="apparmor_parser" Can anyone help?

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  • The perils of double-dash comments [T-SQL]

    - by jamiet
    I was checking my Twitter feed on my way in to work this morning and was alerted to an interesting blog post by Valentino Vranken that highlights a problem regarding the OLE DB Source in SSIS. In short, using double-dash comments in SQL statements within the OLE DB Source can cause unexpected results. It really is quite an important read if you’re developing SSIS packages so head over to SSIS OLE DB Source, Parameters And Comments: A Dangerous Mix! and be educated. Note that the problem is solved in SSIS2012 and Valentino explains exactly why. If reading Valentino’s post has switched your brain into “learn mode” perhaps also check out my post SSIS: SELECT *... or select from a dropdown in an OLE DB Source component? which highlights another issue to be aware of when using the OLE DB Source. As I was reading Valentino’s post I was reminded of a slidedeck by Chris Adkin entitled T-SQL Coding Guidelines where he recommends never using double-dash comments: That’s good advice! @Jamiet

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  • Going home now :-)

    - by Mike Dietrich
    3 weeks of traveling through Asia and Australia - nearly 500 customers and partners in 8 workshops in Tokyo, Seoul, Beijing, Shenzhen, Singapore, Melbourne, Perth and Manila. Great people in all places, many interesting discussions, several new reference prospects for Oracle Database 11g Release 2 - YOU should upgrade as well pretty soon :-) But now it's time to go home. We are a bit exhausted but we really enjoyed it talking to and with you. And I'd suppose we'll meet again the sooner or later. Thanks to everybody - and special thanks to the local colleagues and especially to Abe-san, Kota-san, Blair Layton and Shaheen Ismail for taking care on us, organizing our workshops and the whole setup!!!

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  • SQL SERVER – Enable PowerPivot Plugin in Excel

    - by pinaldave
    Recently I had interesting experience at one conference. My PowerPivot plugin got disabled and I had no clue how to enable the same. After while, I figured out how to enable the same. Once I got back from the event, I searched online and realize that many other people online are facing the same problem. Here is how I solved the problem. When I started Excel it did not load PowerPivot plugin. I found in option>> Add in the plug in to be disabled. I enabled the plugin and it worked very well. Let us see that with images. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: PowerPivot

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  • Why use link classes in oql instead of classes that contain links

    - by Isaac
    itop abstracts its very complex database design with an object query language (oql). For this there are classes definded, like 'Ticket' and 'Server'. Now a Ticket usually is linked to a Server. In my naive way I would give the Ticket class an attribute 'affected_server_list', where I could reference the affected servers. itop does it different: neither Servers nor Tickets know of each other. Instead there is a class 'linkTicketToServer', which provides the link between the two. The first thing I noticed is that it makes oql queries more complex. So I wondered why they designed it this way. One thing that occured to me is that it allows for more flexiblity, in that I can add links without modifying the original classes. Is this allready why one would implement it this way, or are there other reasons for this kind of design?

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  • build command by concatenating string in bash

    - by Lennart Rolland
    I have a bash script that builds a command-line in a string based on some parameters before executing it in one go. The parts that are concatenated to the command string are supposed to be separated by pipes to facilitate a "streaming" of data through each component. A very simplified example: #!/bin/bash part1=gzip -c part2=some_other_command cmd="cat infile" if [ ! "$part1" = "" ] then cmd+=" | $part1" fi if [ ! "$part2" = "" ] then cmd+=" | $part2" fi cmd+="> outfile" #show command. It looks ok echo $cmd #run the command. fails with pipes $cmd For some reason the pipes don't seem to work. When I run this script i get different error messages relating usually to the first part of the command (before the first pipe). So my question is whether or not it is possible to build a command in this way, and what is the best way to do it?

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  • Has RFC2324 been implemented?

    - by anthony-arnold
    I know RFC2324 was an April Fools joke. However, it seems pretty well thought out, and after reading it I figured it wouldn't be out of the question to design an automated coffee machine that used this extension to HTTP. We programmers love to reference this RFC when arguing web standards ("418 I'm a Teapot lolz!") but the joke's kind of on us. Ubiquitous computing research assumes that network-connected coffee machines are probably going to be quite common in the future, along with Internet-connected fruit and just about everything else. Has anyone actually implemented a coffee machine that is controlled via HTCPCP? Not necessarily commercial, but hacked together in a garage, maybe? I'm not talking about just a web server that responds to HTCPCP requests; I mean a real coffee machine that actually makes coffee. I haven't seen an example of that.

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  • Why should ViewModel route actions to Controller when using the MVCVM pattern?

    - by Lea Hayes
    When reading examples across the Internet (including the MSDN reference) I have found that code examples are all doing the following type of thing: public class FooViewModel : BaseViewModel { public FooViewModel(FooController controller) { Controller = controller; } protected FooController Controller { get; private set; } public void PerformSuperAction() { // This just routes action to controller... Controller.SuperAction(); } ... } and then for the view: public class FooView : BaseView { ... private void OnSuperButtonClicked() { ViewModel.PerformSuperAction(); } } Why do we not just do the following? public class FooView : BaseView { ... private void OnSuperButtonClicked() { ViewModel.Controller.SuperAction(); // or, even just use a shortcut property: Controller.SuperAction(); } }

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  • Problem in Addon Domain name binding with existing directory in my webspace

    - by articlestack
    I recently purchased a domain thinkzarahatke.com. At the time of purchasing i selected an option, say url redirect, to my existing site. Further I had entered Naming server detail. But I dint find any other option to change URL rewrite parameters under Domain Name Manager. From the cPanel of my hosting space, I had added new domain as addon and set a sundirectory for it. Now If I am trying to access my new domain directly, it is automatically redirecting to my old website. While if i access some inside directory, like thinkzarahatke.com/blog, then i am able to access to my new site. What wrong i done? Please tell me if i need to do some more settings with addon domain.

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  • Writing an ASP.Net Web based TFS Client

    - by Glav
    So one of the things I needed to do was write an ASP.Net MVC based application for our senior execs to manage a set of arbitrary attributes against stories, bugs etc to be able to attribute whether the item was related to Research and Development, and if so, what kind. We are using TFS Azure and don’t have the option of custom templates. I have decided on using a string based field within the template that is not very visible and which we don’t use to write a small set of custom which will determine the research and development association. However, this string munging on the field is not very user friendly so we need a simple tool that can display attributes against items in a simple dropdown list or something similar. Enter a custom web app that accesses our TFS items in Azure (Note: We are also using Visual Studio 2012) Now TFS Azure uses your Live ID and it is not really possible to easily do this in a server based app where no interaction is available. Even if you capture the Live ID credentials yourself and try to submit them to TFS Azure, it wont work. Bottom line is that it is not straightforward nor obvious what you have to do. In fact, it is a real pain to find and there are some answers out there which don’t appear to be answers at all given they didn’t work in my scenario. So for anyone else who wants to do this, here is a simple breakdown on what you have to do: Go here and get the “TFS Service Credential Viewer”. Install it, run it and connect to your TFS instance in azure and create a service account. Note the username and password exactly as it presents it to you. This is the magic identity that will allow unattended, programmatic access. Without this step, don’t bother trying to do anything else. In your MVC app, reference the following assemblies from “C:\Program Files (x86)\Microsoft Visual Studio 11.0\Common7\IDE\ReferenceAssemblies\v2.0”: Microsoft.TeamFoundation.Client.dll Microsoft.TeamFoundation.Common.dll Microsoft.TeamFoundation.VersionControl.Client.dll Microsoft.TeamFoundation.VersionControl.Common.dll Microsoft.TeamFoundation.WorkItemTracking.Client.DataStoreLoader.dll Microsoft.TeamFoundation.WorkItemTracking.Client.dll Microsoft.TeamFoundation.WorkItemTracking.Common.dll If hosting this in Internet Information Server, for the application pool this app runs under, you will need to enable 32 Bit support. You also have to allow the TFS client assemblies to store a cache of files on your system. If you don’t do this, you will authenticate fine, but then get an exception saying that it is unable to access the cache at some directory path when you query work items. You can set this up by adding the following to your web.config, in the <appSettings> element as shown below: <appSettings> <!-- Add reference to TFS Client Cache --> <add key="WorkItemTrackingCacheRoot" value="C:\windows\temp" /> </appSettings> With all that in place, you can write the following code: var token = new Microsoft.TeamFoundation.Client.SimpleWebTokenCredential("{you-service-account-name", "{your-service-acct-password}"); var clientCreds = new Microsoft.TeamFoundation.Client.TfsClientCredentials(token); var currentCollection = new TfsTeamProjectCollection(new Uri(“https://{yourdomain}.visualstudio.com/defaultcollection”), clientCreds); TfsConfigurationServercurrentCollection.EnsureAuthenticated(); In the above code, not the URL contains the “defaultcollection” at the end of the URL. Obviously replace {yourdomain} with whatever is defined for your TFS in Azure instance. In addition, make sure the service user account and password that was generated in the first step is substituted in here. Note: If something is not right, the “EnsureAuthenticated()” call will throw an exception with the message being you are not authorised. If you forget the “defaultcollection” on the URL, it will still fail but with a message saying you are not authorised. That is, a similar but different exception message. And that is it. You can then query the collection using something like: var service = currentCollection.GetService<WorkItemStore>(); var proj = service.Projects[0]; var allQueries = proj.StoredQueries; for (int qcnt = 0; qcnt < allQueries.Count; qcnt++) {     var query = allQueries[qcnt];     var queryDesc = string.format(“Query found named: {0}”,query.Name); } You get the idea. If you search around, you will find references to the ServiceIdentityCredentialProvider which is referenced in this article. I had no luck with this method and it all looked too hard since it required an extra KB article and other magic sauce. So I hope that helps. This article certainly would have helped me save a boat load of time and frustration.

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  • AJAX Requests & Client-Side JavaScript

    - by Sarah24
    I am new to AJAX and trying to understand a question I've been given: A HTTP request is generated by a form which contains some drop-down list. When the form is submitted, a new web page is displayed with some relevant text information (which is dependent on the list item selected). Now, the same parameters are sent to the server via an AJAX request, and the same text information is returned. Q. What tasks would the client-side JavaScript have to do to ensure a valid request was constructed and sent? Any useful links or quick explanations greatly appreciated.

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  • What are the files pushed to MDS?

    - by harsh.singla
    All files which are under AIAComponents will move to MDS. This contains EnterpriseObjectLibrary, EnterpriseBusinessServiceLibrary, ApplicationObjectLibrary, ApplicationBusinessServiceLibrary, B2BObjectLibrary, ExtensionServiceLibrary, and UtilityArtifacts. Also there are some common transformation (.xsl) files, which are kept under Transformations folder, moved to MDS. AIAConfigurationProperties.xml file will be there in MDS. Every cross reference (.xref) object will also be there. Every Domain value Map (.dvm) will also be there. Common fault policy, which by default included in composite during composite generation, if a user does not choose to customize fault policy. All these files are location under AIAMetaData directory and then placed in their respective folders. We are planning to put Error handling and BSR systems related data also to MDS.

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  • Some New .NET Downloads and Resources

    - by Kevin Grossnicklaus
    Last week I was fortunate enough to spend time in Redmond on Microsoft’s campus for the 2011 Microsoft MVP Summit.  It was great to hang out with a number of old friends and get the opportunity to talk tech with the various product teams up at Microsoft.  The weather wasn’t exactly sunny but Microsoft always does a great job with the Summit and everyone had a blast (heck, I even got to run the bases at SafeCo field) While much of what we saw is covered under NDA, there a ton of great things in the pipeline from Microsoft and many things that are already available (or just became so) that I wasn’t necessarily aware of.  The purpose of this post is to share some of the info I learned on resources and tools available to .NET developers today.  Please let me know if you have any questions (or if you know of something else cool which might benefit others). Enjoy! Visual Studio 2010 SP1 Microsoft has issued the RTM release of Visual Studio 2010 SP1.  You can download the full SP1 on MSDN as of today (March 10th to the general public) and take advantage of such things as: Silverlight 4 is included in the box (as opposed to a separate install) Silverlight 4 Profiling WCF RIA Services SP1 Intellitrace for 64-bit and SharePoint ASP.NET now easily supports IIS Express and SQL CE Want a description of all that’s new beyond the above biased list (which arguably only contains items I think are important)?  Check out this KB article. Portable Library Tools CTP Without much fanfare Microsoft has released a CTP of a new add-in to Visual Studio 2010 which simplifies code sharing between projects targeting different runtimes (i.e. Silverlight, WPF, Win7 Phone, XBox).   With this Add-In installed you can add a new project of type “Portable Library” and specify which platforms you wish to target.  Once that is done, any code added to this library will be limited to use only features which are common to all selected frameworks.  Other projects can now reference this portable library and be provided assemblies custom built to their environment.  This greatly simplifies the current process of sharing linked files between platforms like WPF and Silverlight.  You can find out more about this CTP and how it works on this great blog post. Visual Studio Async CTP Microsoft has also released a CTP of a set of language and framework enhancements to provide a much more powerful asynchronous programming model.   Due to the focus on async programming in all types of platforms (and it being the ONLY option in Silverlight and Win7 phone) a move towards a simpler and more understandable model is always a good thing. This CTP (called Visual Studio Async CTP) can be downloaded here.  You can read more about this CTP on this blog post. MSDN Code Samples Gallery Microsoft has also launched new code samples gallery on their MSDN site: http://code.msdn.microsoft.com/.   This site allows you to easily search for small samples of code related to a particular technology or platform.  If a sample of code you are looking for is not found, you can request one via the site and other developers can see your request and provide a sample to the site to suit your needs.  You can also peruse requested samples and, if you find a scenario where you can provide value, upload your own sample for the benefit of others.  Samples are packaged into the VS .vsix format and include any necessary references/dependencies.  By using .vsix as the deployment mechanism, as samples are installed from the site they are kept in your Visual Studio 2010 Samples Gallery and kept for your future reference. If you get a chance, check out the site and see how it is done.  Although a somewhat simple concept, I was very impressed with their implementation and the way they went about trying to suit a need.  I’ll definitely be looking there in the future as need something or want to share something. MSDN Search Capabilities Another item I learned recently and was not aware of (that might seem trivial to some) is the power of the MSDN site’s search capabilities.  Between the Code Samples Gallery described above and the search enhancements on MSDN, Microsoft is definitely investing in their platform to help provide developers of all skill levels the tools and resources they need to be successful. What do I mean by the MSDN search capability and why should you care? If you go to the MSDN home page (http://msdn.microsoft.com) and use the “Search MSDN with Big” box at the very top of the page you will see some very interesting results.  First, the search actually doesn’t just search the MSDN library it searches: MSDN Library All Microsoft Blogs CodePlex StackOverflow Downloads MSDN Magazine Support Knowledgebase (I’m not sure it even ends there but the above are all I know of) Beyond just searching all the above locations, the results are formatted very nicely to give some contextual information based on where the result came from.  For example, if a keyword search returned results from CodePlex, each row in the search results screen would include a large amount of information specific to CodePlex such as: Looking at the above results immediately tells you everything from the page views to the CodePlex ratings.  All in all, knowing that this much information is indexed and available from a single search location will lead me to utilize this as one of my initial searches for development information.

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  • What light attenuation function does UDK use?

    - by ananamas
    I'm a big fan of the light attenuation in UDK. Traditionally I've always used the constant-linear-quadratic falloff function to control how "soft" the falloff is, which gives three values to play with. In UDK you can get similar results, but you only need to tweak one value: FalloffExponent. I'm interested in what the actual mathematical function here is. The UDK lighting reference describes it as follows: FalloffExponent: This allows you to modify the falloff of a light. The default falloff is 2. The smaller the number, the sharper the falloff and the more the brightness is maintained until the radius is reached. Does anyone know what it's doing behind the scenes?

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  • Removing existing filtered pages from Google's index: noindex / 301 / canonical to non-filtered page?

    - by Noam
    I've decided to remove some of my site's pages from the Google index to focus more of the indexed pages on higher quality pages. The pages I'm going to remove are already in the index. These removed pages are filtered pages which will continue to exist, I just don't want them in the google index because they add little quality to the same page without any filter selected. I've added in webmaster tools specification of narrow for the parameters that set these filters, but it doesn't seem this changes anything in how he handles these pages. So I'm considering three options: Adding <meta name="robots" content="noindex" /> to the html header of these filtered pages 301 to the non-filtered page that contains the most similar information and will remain in the index Canonical tag. Which I'm not sure is exactly the mainstream use case, as these aren't really the same pages. Which should I use?

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  • JavaOne - Java SE Embedded Booth - Digi - Home Health Hub (HHH)

    - by David Clack
    Hi All,  So another exciting platform we will have in the booth at JavaOne is the Digi  Home Health Hub (HHH) platform. http://www.digi.com/products/wireless-wired-embedded-solutions/single-board-computers/idigi-telehealth-application-kit#overview This is a Freescale reference design that has been built by Digi, the system is powered by a Freescale i.MX28 ARM SOC, what's really exciting me is it has every wireless protocol you could ever want on a single motherboard. Ethernet, 802.11b/g/n Wi-Fi, Bluetooth, ZigBee, configurable Sub-GHz radio, NFC plus USB, audio and LCD/touch screen option. I've been experimenting with lots of wireless capable healthcare products in the last few months, plus some Bluetooth Pulse / Oxy meters, we have been looking at how the actual healthcare wireless protocols work. Steve Popovich - Vice President, Digi Internationalwill be doing a talk at the Java Embedded @ JavaOne conference in the Hotel Nikko, right next door to the JavaOne show in the Hilton. If you are registered at JavaOne you can come over to the Java Embedded @ JavaOne for $100 Come see us in booth 5605 See you there Dave

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  • Avoiding Hacker Trix

    - by Mike Benkovich
    Originally posted on: http://geekswithblogs.net/benko/archive/2014/08/20/avoiding-hacker-trix.aspxThis week we're doing a session called "Avoiding Hacker Trix" which goes thru some of the top web exploits that you should be aware of. In this webcast we will cover a variety of things including what we call the secure development process, cross site scripting attack, one click attack, SQL Injection and more. There are a bunch of links we cover, but rather than having you copy these down I'm providing them here... Links from the slide deck: Anti-XSS Library Download www.Fiddler2.com www.HelloSecureWorld.com Open Source Web Application Project - Top 10 Exploits Exploit: Cross Site Scripting - Paypal Exploit: SQL Injection - www.ri.gov Exploit: Cross Site Scripting - FTD Exploit: Insecure Direct Object Reference - Cahoots Exploit: Integer Overflow - Apple

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  • Rule Engine in .net

    - by user641812
    I have to import data from excel to SQL database. Excel data contains various parameters and there value like P1,P1,P4,P5 etc. I have to apply business rules Like if( P1 100 and P1 < 200) then insert the record in database. Similarly in some cases string values are also validated. Can I have any open source rule engine that contains UI to change , add , delete the rules. Am using C# to read the excel and and insert the records One more thing which is best approach: Read excel first and store every record as an object in a collection, then iterate through the collection, apply business rules on every object and then insert record in the database Or Read one record from excel apply business rule and then insert record in the database. Repeat the process for whole excel.

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  • To Bit or Not To Bit

    - by Johnm
    'Twas a long day of troubleshooting and firefighting and now, with most of the office vacant, you face a blank scripting window to create a new table in his database. Many questions circle your mind like dirty water gurgling down the bathtub drain: "How normalized should this table be?", "Should I use an identity column?", "NVarchar or Varchar?", "Should this column be NULLABLE?", "I wonder what apple blue cheese bacon cheesecake tastes like?" Well, there are times when the mind goes it's own direction. A Bit About Bit At some point during your table creation efforts you will encounter the decision of whether to use the bit data type for a column. The bit data type is an integer data type that recognizes only the values of 1, 0 and NULL as valid. This data type is often utilized to store yes/no or true/false values. An example of its use would be a column called [IsGasoline] which would be intended to contain the value of 1 if the row's subject (a car) had a gasoline engine and a 0 if the subject did not have a gasoline engine. The bit data type can even be found in some of the system tables of SQL Server. For example, the sysssispackages table in the msdb database which contains SQL Server Integration Services Package information for the packages stored in SQL Server. This table contains a column called [IsEncrypted]. A value of 1 indicates that the package has been encrypted while the value of 0 indicates that it is not. I have learned that the most effective way to disperse the crowd that surrounds the office coffee machine is to engage into SQL Server debates. The bit data type has been one of the most reoccurring, as well as the most enjoyable, of these topics. It contains a practical side and a philosophical side. Practical Consideration This data type certainly has its place and is a valuable option for database design; but it is often used in situations where the answer is really not a pure true/false response. In addition, true/false values are not very informative or scalable. Let's use the previously noted [IsGasoline] column for illustration. While on the surface it appears to be a rather simple question when evaluating a car: "Does the car have a gasoline engine?" If the person entering data is entering a row for a Jeep Liberty, the response would be a 1 since it has a gasoline engine. If the person is entering data is entering a row for a Chevrolet Volt, the response would be a 0 since it is an electric engine. What happens when a person is entering a row for the gasoline/electric hybrid Toyota Prius? Would one person's conclusion be consistent with another person's conclusion? The argument could be made that the current intent for the database is to be used only for pure gasoline and pure electric engines; but this is where the scalability issue comes into play. With the use of a bit data type a database modification and data conversion would be required if the business decided to take on hybrid engines. Whereas, alternatively, if the int data type were used as a foreign key to a reference table containing the engine type options, the change to include the hybrid option would only require an entry into the reference table. Philosophical Consideration Since the bit data type is often used for true/false or yes/no data (also called Boolean) it presents a philosophical conundrum of what to do about the allowance of the NULL value. The inclusion of NULL in a true/false or yes/no response simply violates the logical principle of bivalence which states that "every proposition is either true or false". If NULL is not true, then it must be false. The mathematical laws of Boolean logic support this concept by stating that the only valid values of this scenario are 1 and 0. There is another way to look at this conundrum: NULL is also considered to be the absence of a response. In other words, it is the equivalent to "undecided". Anyone who watches the news can tell you that polls always include an "undecided" option. This could be considered a valid option in the world of yes/no/dunno. Through out all of these considerations I have discovered one absolute certainty: When you have found a person, or group of persons, who are willing to entertain a philosophical debate of the bit data type, you have found some true friends.

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