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  • php not well formed?

    - by Idealflip
    Hi Everyone, when my site loads, it stops half way because of specific php code. When I try commenting out the php code, the whole page loads properly (input boxes, buttons etc.) This is the code that causes the issue <?php //if the add location button is clicked, the add location, the whole form will not be submitted if($_REQUEST['command'] == 'Add'){ if($_POST['companyLocation'] == ""){ $errmsg="Please enter a location1"; } elseif($_POST['companySize'] == ""){ $errmsg="Please enter a size for the location"; } else{ $location = Location::instance(); $testing = $location->doesExist($_POST['companyLocation']); if ($testing == true){ $errmsg="Location already exists"; } else{ $objLocation = new Obj_Location(); $objLocation->set_Name($_POST['companyLocation']); $objLocation->set_Size($_POST['companySize']); $location->addLocation($objLocation); $location->saveInstance(); } } } //this is the part that breaks! when I comment it out, the page loads properly. $location = Location::instance(); $location->deleteItem($_GET["item"]); $location->saveInstance(); $location->listItems(); ?>

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  • How can I create global context variables in JBOSS?

    - by NobodyMan
    This is a follow-up to a question I posted a while back: "Can I use a single WAR in multiple environments?". I was able to create a single-war solution in Tomcat, but now we are migrating our app to JBoss 4.2 and I can't figure out how to set up global environment variables. In Tomcat 6 this was pretty straightforward: I simply put the following snippet in tomcat/conf/Catalina/myappname.xml: <Context ...> <Environment name="TARGET_ENV" value="DEV" type="java.lang.String" override="false"/> </Context> Then in my app I was able to resolve the environment name with the following: Context context = (Context) InitialContext().lookup("java:comp/env"); String targetEnvironment = (String) context.lookup("TARGET_ENV"); The problem is that I can't find out where/how to place global variables in JBoss. I've tried putting the <Environment> tag in the following files to no avail: server/all/deploy/jboss-web.deployer/context.xml server/default/deploy/jboss-web.deployer/context.xml I know that I can put environment variables in my app's web.xml but that defeats the purpose of having a unified war - I'd still need custom .war's for dev, qa and prod. I'm a JBoss newbie so if there's any additional information that would help just let me know and I'll append to this question. Many thanks! --N

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  • Setting up magic routes for plugins in CakePHP 1.3?

    - by Matt Huggins
    I'm working on upgrading my project from CakePHP 1.2 to 1.3. In the process, it seems that the "magic" routing for plugins by which a controller name (e.g.: "ForumsController") matching the plugin name (e.g.: "forums") no longer automatically routes to the root of the plugin URL (e.g.: "www.example.com/forums" pointing to plugin "forums", controller "forums", action "index"). The error message given is as follows: Error: ForumsController could not be found. Error: Create the class ForumsController below in file: app/controllers/forums_controller.php <?php class ForumsController extends AppController { var $name = 'Forums'; } ?> In fact, even if I navigate to "www.example.com/forums/forums" or "www.example.com/forums/forums/index", I get the same exact error. Do I need to explicitly set up routes to every single plugin I use? This seems to destroy a lot of the magic I like about CakePHP. I've only found that doing the following works: Router::connect('/forums/:action/*', array('plugin' => 'forums', 'controller' => 'forums')); Router::connect('/forums', array('plugin' => 'forums', 'controller' => 'forums', 'action' => 'index')); Setting up 2 routes for every single plugin seems like overkill, does it not? Is there a better solution that will cover all my plugins, or at least reduce the number of routes I need to set up for each plugin?

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  • Working with fields which can mutate or be new instances altogether

    - by dotnetdev
    Structs are usually used for immutable data, eg a phone number, which does not mutate, but instead you get a new one (eg the number 000 becoming 0001 would mean two seperate numbers). However, pieces of information like Name, a string, can either mutate (company abc changing its name to abcdef, or being given a new name like def). For fields like this, I assume they should reside in the mutable class and not an immutable structure? My way of structuring code is to have an immutable concept, like Address (any change is a new address completely), in a struct and then reference it from a class like Customer, since Customer always has an address. So I would put CompanyName, or Employer, in the class as it is mutable. But a name can either mutate and so be the same 1 instance, or a new name setup and while the company still owning the first name too. Would the correct pattern for assigning a new instance (eg a new company name but the old name still owned by the company) be?: string name = ""; string newName = new string(); newName = "new"; name = newName; And a mutation just the standard assignment pattern? Thanks

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  • Connection Pool Strategy: Good, Bad or Ugly?

    - by Drew
    I'm in charge of developing and maintaining a group of Web Applications that are centered around similar data. The architecture I decided on at the time was that each application would have their own database and web-root application. Each application maintains a connection pool to its own database and a central database for shared data (logins, etc.) A co-worker has been positing that this strategy will not scale because having so many different connection pools will not be scalable and that we should refactor the database so that all of the different applications use a single central database and that any modifications that may be unique to a system will need to be reflected from that one database and then use a single pool powered by Tomcat. He has posited that there is a lot of "meta data" that goes back and forth across the network to maintain a connection pool. My understanding is that with proper tuning to use only as many connections as necessary across the different pools (low volume apps getting less connections, high volume apps getting more, etc.) that the number of pools doesn't matter compared to the number of connections or more formally that the difference in overhead required to maintain 3 pools of 10 connections is negligible compared to 1 pool of 30 connections. The reasoning behind initially breaking the systems into a one-app-one-database design was that there are likely going to be differences between the apps and that each system could make modifications on the schema as needed. Similarly, it eliminated the possibility of system data bleeding through to other apps. Unfortunately there is not strong leadership in the company to make a hard decision. Although my co-worker is backing up his worries only with vagueness, I want to make sure I understand the ramifications of multiple small databases/connections versus one large database/connection pool.

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  • XSLT - How to select top a to top b

    - by user812241
    how can I extract the first 2 C-Values ('Baby' and 'Cola') where B is 'RED'. Input instance is: <Root> <A> <B>BLACK</B> <C>Apple</C> </A> <A> <B>RED</B> <C>Baby</C> </A> <A> <B>GREEN</B> <C>Sun</C> </A> <A> <B>RED</B> <C>Cola</C> </A> <A> <B>RED</B> <C>Mobile</C> </A> </Root> Output instance must be: <Root> <D>Baby</D> <D>Cola</D> </Root> I thought about the combination of for-each and global variables. But in XSLT it is not possible to change the value for a global variable to break the for-each. I have no idea anymore.

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  • C#: Need one of my classes to trigger an event in another class to update a text box

    - by Matt
    Total n00b to C# and events although I have been programming for a while. I have a class containing a text box. This class creates an instance of a communication manager class that is receiving frames from the Serial Port. I have this all working fine. Every time a frame is received and its data extracted, I want a method to run in my class with the text box in order to append this frame data to the text box. So, without posting all of my code I have my form class... public partial class Form1 : Form { CommManager comm; public Form1() { InitializeComponent(); comm = new CommManager(); } private void updateTextBox() { //get new values and update textbox } . . . and I have my CommManager class class CommManager { //here we manage the comms, recieve the data and parse the frame } SO... essentially, when I parse that frame, I need the updateTextBox method from the form class to run. I'm guessing this is possible with events but I can't seem to get it to work. I tried adding an event handler in the form class after creating the instance of CommManager as below... comm = new CommManager(); comm.framePopulated += new EventHandler(updateTextBox); ...but I must be doing this wrong as the compiler doesn't like it... Any ideas?!

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  • Using Mercurial (hg), can you just "hg backout" all the commits you did for the files you don't want

    - by Jian Lin
    Using Mercurial (hg), can you just "hg backout" all the commits you did for the files you don't want to push, and then do a push? Because Mercurial (or Git) won't let us push a single file or a single folder to another repository, so I am thinking: 1) How about, we just look at the commit we did, and hg backout the ones we don't want to push. 2) hg out -v to see the list of files that will be pushed 3) now do the push by hg push Is this a good way? This is because I got the following advice: 1) Don't commit that file if you don't want it to be pushed (but sometimes even just for experimentation, I do want to keep the intermediate revisions) (-- maybe I can hg commit and hg backout right away to prevent it from being pushed.) 2) Some people told me just to hg clone tmp from that repository i want to push to, and then copy the local file over to this tmp working directory, hg commit to this tmp repository, and then do a push. But I found that the hg clone tmp will take up 400MB of new data and files, and make the hard drive work very hard, just to push 1 file? So I would rather not use this method.

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  • drupal themes: how do I include several css files / js files on my theme's .info file?

    - by egarcia
    I'm creating a new Drupal theme. Until now, I only needed to include a single css file and a single js file. So my theme.info file had something like this: stylesheets[all][] = css/style.css scripts[] = js/script.js Now I must include jquery and jquery-ui in order to use a calendar date. These come with 2 new javascript files, and 1 additonal css file that I must add to the site. The calendar input form is going to be used in all pages (on a side block) so it is ok for me to load the extra css/javascript on all pages. I think the easiest thing would be to reference them on the .info file itself. At first I tried to just put them there with separate spaces: stylesheets[all][] = css/style.css css/ui-lightness/jquery-ui-1.8.1.custom.css scripts[] = js/script.js js/jquery-1.4.2.min.js js/jquery-ui-1.8.1.custom.min.js I emptied drupal's cache and... none of them loaded. I then tried separating each file with a comma, and flushing the cache again. Same result. I've browsed some drupal pages, but could not find how to add several javascript/css files on one theme (they always seem to add just 1 of each). So, how do I include several css/javascript files on the .info file?

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  • Using Memcached in Python/Django - questions.

    - by Thomas
    I am starting use Memcached to make my website faster. For constant data in my database I use this: from django.core.cache import cache cache_key = 'regions' regions = cache.get(cache_key) if result is None: """Not Found in Cache""" regions = Regions.objects.all() cache.set(cache_key, regions, 2592000) #(2592000sekund = 30 dni) return regions For seldom changed data I use signals: from django.core.cache import cache from django.db.models import signals def nuke_social_network_cache(self, instance, **kwargs): cache_key = 'networks_for_%s' % (self.instance.user_id,) cache.delete(cache_key) signals.post_save.connect(nuke_social_network_cache, sender=SocialNetworkProfile) signals.post_delete.connect(nuke_social_network_cache, sender=SocialNetworkProfile) Is it correct way? I installed django-memcached-0.1.2, which show me: Memcached Server Stats Server Keys Hits Gets Hit_Rate Traffic_In Traffic_Out Usage Uptime 127.0.0.1 15 220 276 79% 83.1 KB 364.1 KB 18.4 KB 22:21:25 Can sombody explain what columns means? And last question. I have templates where I am getting much records from a few table (relationships). So in my view I get records from one table and in templates show it and related info from others. Generating page last a few seconds for very small table (<100records). Is it some easy way to cache queries from templates? Have I to do some big structure in my view (with all related tables), cache it and send to template?

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  • FragmentActivity doesn't see activity in onActivityCreate(), after screen orientation changed

    - by hai bison
    I'm using Android support library v13. There is a strange thing I couldn't understand. When creating new activity, I load fragment as: Main activity layout: ... <FrameLayout android:id="@+id/fragment_1" ... /> In onCreate() of main activity: mFragment = (FragmentActivity) getSupportFragmentManager().findFragmentById(R.id.fragment_1); // if screen orientation changed, no need to create new instance of fragment if (mFragment == null) { mFragment = ...; // create new instance of fragment FragmentTransaction ft = getSupportFragmentManager().beginTransaction(); ft.replace(R.id.fragment_1, mFragment); // because this is called ONCE, we can use this method ft.commitAllowingStateLoss(); } Now, everything works perfectly in emulators 1.5, 1.6 and 2.2. I have a phone 2.2.2. But there is an exception: if the app is running, and screen orientation changed. Inside onActivityCreated(), getActivity() sometimes returns null. This only happens in emulators 1.5/ 1.6/ 2.2. My phone 2.2.2 works very well, I test hundreds of times but never catch that bug. Even other emulators 3.x, 4.x work well too. Unfortunately I don't have phone 1.5/ 1.6/ 2.2. So did you have experience with this? Is that a bug of the support library, or emulators? Could you please help me? Thank you in advance.

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  • Unit Testing the Use of TransactionScope

    - by Randolpho
    The preamble: I have designed a strongly interfaced and fully mockable data layer class that expects the business layer to create a TransactionScope when multiple calls should be included in a single transaction. The problem: I would like to unit test that my business layer makes use of a TransactionScope object when I expect it to. Unfortunately, the standard pattern for using TransactionScope is a follows: using(var scope = new TransactionScope()) { // transactional methods datalayer.InsertFoo(); datalayer.InsertBar(); scope.Complete(); } While this is a really great pattern in terms of usability for the programmer, testing that it's done seems... unpossible to me. I cannot detect that a transient object has been instantiated, let alone mock it to determine that a method was called on it. Yet my goal for coverage implies that I must. The Question: How can I go about building unit tests that ensure TransactionScope is used appropriately according to the standard pattern? Final Thoughts: I've considered a solution that would certainly provide the coverage I need, but have rejected it as overly complex and not conforming to the standard TransactionScope pattern. It involves adding a CreateTransactionScope method on my data layer object that returns an instance of TransactionScope. But because TransactionScope contains constructor logic and non-virtual methods and is therefore difficult if not impossible to mock, CreateTransactionScope would return an instance of DataLayerTransactionScope which would be a mockable facade into TransactionScope. While this might do the job it's complex and I would prefer to use the standard pattern. Is there a better way?

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  • RadioButtonGroup with each RadioButton added in components?

    - by futureal
    Hi, Working in Flex 3, I have a series of components being rendered on a canvas, each of which should represent a single potential selection, ideally in a RadioButtonGroup. So in my parent canvas I am defining the RadioButtonGroup, and each component provides a single RadioButton. However, this doesn't seem to work. Suppose there is a component called aComponent defined as such: <mx:Canvas ...> ... <mx:RadioButton id="someButton" groupName="myRadioButtonGroup" ... /> </mx:Canvas> The outer canvas: <mx:Canvas ...> ... <mx:Script> public function doesSomething():void { var myComponent:aComponent = new aComponent(); outerCanvas.addChild(myComponent); } </mx:Script> ... <mx:RadioButtonGroup id="myRadioButtonGroup" /> </mx:Canvas> So my guess was that at this point if, say, four of these components were added, the radio buttons would behave in mutually exclusive fashion and I'd be able to access myRadioButtonGroup.selectedValue to get the current selection. However, it doesn't seem to work that way. Is what I'm trying to do even possible, or have I maybe just missed something? Thanks!

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  • sql server 2005 command line install error ADD_LOCAL property already installed

    - by Belliez
    I have a silent installation of SQL Server 2005 that works great when installing SQL Server on a machine that does not have it already installed. I use the following parameters when I perform the installation: #define SQL_SILENT "/passive /qb" #define SQL_USERNAME "username=MyUserName" #define SQL_COMPANYNAME "companyname=MyCompanyName" #define SQL_ADDLOCAL "ADDLOCAL=SQL_Engine" #define SQL_UPGRADE "" #define SQL_DISABLENETWORKPROTOCOLS "disablenetworkprotocols=0" #define SQL_INSTANCENAME "instancename=MYSQLINSTANCE" #define SQL_SQLAUTOSTART "SQLAUTOSTART=1" #define SQL_SECURITYMODE "SECURITYMODE=SQL" #define SQL_SAPWD "SAPWD=StrongPassword" #define SQL_SQLACCOUNT "SQLACCOUNT=""""" #define SQL_SQLPASSWORD "SQLPASSWORD=""""" It installs the instance of SQL Server Express without a problem. However, when I attempt to install SQL Server on a machine that already has another instance with components I get the following error: *"A component that you have specified in the ADD_LOCAL property is already installed. To upgrade the existing component, refer to the template.ini and set the UPGRADE property to the name of the component."* I have also tried using the UPGRADE method as per the error message #define SQL_UPGRADE "UPGRADE=SQL_Engine INSTANCENAME=MYSQLINSTANCE" but get the following error: "SQL Server Setup cannot perform the upgrade because the component is not installed on the computer. To proceed, verify the component to be upgraded in currently installed, and that the component to be upgraded is specified in the ADDLOCAL property." Does anyone have any suggestions? Thank you

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  • using yield in C# like I would in Ruby

    - by Sarah Vessels
    Besides just using yield for iterators in Ruby, I also use it to pass control briefly back to the caller before resuming control in the called method. What I want to do in C# is similar. In a test class, I want to get a connection instance, create another variable instance that uses that connection, then pass the variable to the calling method so it can be fiddled with. I then want control to return to the called method so that the connection can be disposed. I guess I'm wanting a block/closure like in Ruby. Here's the general idea: private static MyThing getThing() { using (var connection = new Connection()) { yield return new MyThing(connection); } } [TestMethod] public void MyTest1() { // call getThing(), use yielded MyThing, control returns to getThing() // for disposal } [TestMethod] public void MyTest2() { // call getThing(), use yielded MyThing, control returns to getThing() // for disposal } ... This doesn't work in C#; ReSharper tells me that the body of getThing cannot be an iterator block because MyThing is not an iterator interface type. That's definitely true, but I don't want to iterate through some list. I'm guessing I shouldn't use yield if I'm not working with iterators. Any idea how I can achieve this block/closure thing in C# so I don't have to wrap my code in MyTest1, MyTest2, ... with the code in getThing()'s body?

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  • Create cross platform Java SWT Application

    - by mchr
    I have written a Java GUI using SWT. I package the application using an ANT script (fragment below). <jar destfile="./build/jars/swtgui.jar" filesetmanifest="mergewithoutmain"> <manifest> <attribute name="Main-Class" value="org.swtgui.MainGui" /> <attribute name="Class-Path" value="." /> </manifest> <fileset dir="./build/classes" includes="**/*.class" /> <zipfileset excludes="META-INF/*.SF" src="lib/org.eclipse.swt.win32.win32.x86_3.5.2.v3557f.jar" /> </jar> This produces a single jar which on Windows I can just double click to run my GUI. The downside is that I have had to explicitly package the windows SWT package into my jar. I would like to be able to run my application on other platforms (primarily Linux and OS X). The simplest way to do it would be to create platform specific jars which packaged the appropriate SWT files into separate JARs. Is there a better way to do this? Is it possible to create a single JAR which would run on multiple platforms?

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  • Python base classes share attributes?

    - by tad
    Code in test.py: class Base(object): def __init__(self, l=[]): self.l = l def add(self, num): self.l.append(num) def remove(self, num): self.l.remove(num) class Derived(Base): def __init__(self, l=[]): super(Derived, self).__init__(l) Python shell session: Python 2.6.5 (r265:79063, Apr 1 2010, 05:22:20) [GCC 4.4.3 20100316 (prerelease)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import test >>> a = test.Derived() >>> b = test.Derived() >>> a.l [] >>> b.l [] >>> a.add(1) >>> a.l [1] >>> b.l [1] >>> c = test.Derived() >>> c.l [1] I was expecting "C++-like" behavior, in which each derived object contains its own instance of the base class. Is this still the case? Why does each object appear to share the same list instance?

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  • Importing data from third party datasource (open architecture design )

    - by mare
    How would you design an application (classes, interfaces in class library) in .NET when we have a fixed database design on our side and we need to support imports of data from third party data sources, which will most likely be in XML? For instance, let us say we have a Products table in our DB which has columns Id Title Description TaxLevel Price and on the other side we have for instance Products: ProductId ProdTitle Text BasicPrice Quantity. Currently I do it like this: Have the third party XML convert to classes and XSD's and then deserialize its contents into strong typed objects (what we get as a result of this process is classes like ThirdPartyProduct, ThirdPartyClassification, etc.). Then I have methods like this: InsertProduct(ThirdPartyProduct newproduct) I do not use interfaces at the moment but I would like them to. What I would like is implement something like public class Contoso_ProductSynchronization : ProductSynchronization InsertProduct(ContosoProduct p) where ProductSynchronization will be an interface or abstract class. There will most likely be many implementations of ProductSynchronization. I cannot hardcode the types - classes like ContosoProduct, NorthwindProduct might be created from the third party XML's (so preferably I would continue to use deserialization). Hopefully someone will understand what I'm trying to explain here. Just imagine you are the seller and you have numerous providers and each one uses their own proprietary XML format. I don't mind the development, which will of course be needed everytime new format appears, because it will only require 10-20 methods to be implemented, I just want the architecture to be open and support that.

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  • Flash compiler error 1061: Call to a possibly undefined method run... but run exists!

    - by Zane Geiger
    So I've been working on making a game in Processing but I think Flash would be a better way to get more people playing it, so I've decided to learn Flash. The problem is that I keep getting really stupid errors on incredibly simple things. For instance, I want to make a 'Block' object to use in a platform game. So I make a new .as file, name it Block.as, and define the Block class within it like so: package { public class Block { public function Block() { // constructor code } public function run() { } } } I don't want to add the code yet, I just want to ensure that this works. So in my main timeline code, I try to create an instance of the Block object and execute its run method: var block1:Block = new Block(); block1.run(); Every time it gives me this inane error: Scene 1, Layer 'Layer 1', Frame 1, Line 2 1061: Call to a possibly undefined method run through a reference with static type Block. What undefined method!? It's defined RIGHT THERE in Block.as. The class file is even in the same folder and everything. I'm getting REALLY annoyed at how poorly Flash handles such a ridiculously simple project. Does anyone know why Flash hates me?

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  • Is there any point in using a volatile long?

    - by Adamski
    I occasionally use a volatile instance variable in cases where I have two threads reading from / writing to it and don't want the overhead (or potential deadlock risk) of taking out a lock; for example a timer thread periodically updating an int ID that is exposed as a getter on some class: public class MyClass { private volatile int id; public MyClass() { ScheduledExecutorService execService = Executors.newScheduledThreadPool(1); execService.scheduleAtFixedRate(new Runnable() { public void run() { ++id; } }, 0L, 30L, TimeUnit.SECONDS); } public int getId() { return id; } } My question: Given that the JLS only guarantees that 32-bit reads will be atomic is there any point in ever using a volatile long? (i.e. 64-bit). Caveat: Please do not reply saying that using volatile over synchronized is a case of pre-optimisation; I am well aware of how / when to use synchronized but there are cases where volatile is preferable. For example, when defining a Spring bean for use in a single-threaded application I tend to favour volatile instance variables, as there is no guarantee that the Spring context will initialise each bean's properties in the main thread.

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  • Integrated Windows authentication in IIS causing ADO.NET failure

    - by TrueWill
    We have a .NET 3.5 Web Service running under IIS. It must use identity impersonate="true" and Integrated Windows authentication in order to authenticate to third-party software. In addition, it connects to a SQL Server database using ADO.NET and SQL Server Authentication (specifying a fixed User ID and Password in the connection string). Everything worked fine until the database was moved to another SQL Server. Then the Web Service would throw the following exception: A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server) This error only occurs if identity impersonate is true in the Web.config. Again, the connection string hasn't changed and it specifies the user. I have tested the connection string and it works, both under the impersonated account and under the service account (and from both the remote machine and the server). What needs to be changed to get this to work with impersonation?

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  • Generating jquery 'rules' from business model to UI in asp.net mvc

    - by jim
    Hi all, I've had a good look around and am certain that there's no matching question on SO, so here goes. Has anyone created a 'helper' method on their model that generates jquery (or plain javascript) rules validation dynamically, based on the criteria/rules that are contained within the object and taken from a repository (i.e. DB). What i'm thinking of is a discrete set of partial views (and associated models) that have rules at the business logic 'level' and rather than (or in combination with) validating the rule(s) at postback, translating the same rules into tightly focussed jquery methods that work identically at client (js) and server (c#) levels. I can see benefits here re performance. Also, the rules definitions could be created in a single place (in c#) and the jquery generated off of that, thus allowing single edits to update both code streams. I appreciate that there would be limitations imposed by language specific contstraints but the general principle could be quite interesting if used appropriately. I'm also aware that testibility could be an issue when using two different language structures and hoping to achieve similar test outcomes - but those aside... any thoughts or experiences of similar out there?? cheers jimi

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  • Schema for storing "binary" values, such as Male/Female, in a database

    - by latentflip
    Intro I am trying to decide how best to set up my database schema for a (Rails) model. I have a model related to money which indicates whether the value is an income (positive cash value) or an expense (negative cash value). I would like separate column(s) to indicate whether it is an income or an expense, rather than relying on whether the value stored is positive or negative. Question: How would you store these values, and why? Have a single column, say Income, and store 1 if it's an income, 0 if it's an expense, null if not known. Have two columns, Income and Expense, setting their values to 1 or 0 as appropriate. Something else? I figure the question is similar to storing a person's gender in a database (ignoring aliens/transgender/etc) hence my title. My thoughts so far Lookup might be easier with a single column, but there is a risk of mistaking 0 (false, expense) for null (unknown). Having seperate columns might be more difficult to maintain (what happens if we end up with a 1 in both columns? Maybe it's not that big a deal which way I go, but it would be great to have any concerns/thoughts raised before I get too far down the line and have to change my code-base because I missed something that should have been obvious! Thanks, Philip

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  • Should a C++ constructor do real work?

    - by Wade Williams
    I'm strugging with some advice I have in the back of my mind but for which I can't remember the reasoning. I seem to remember at some point reading some advice (can't remember the source) that C++ constructors should not do real work. Rather, they should initialize variables only. The advice when on to explain that real work should be done in some sort of init() method, to be called separately after the instance was created. The situation is I have a class that represents a hardware device. It makes logical sense to me for the constructor to call the routines that query the device in order to build up the instance variables that describe the device. In other words, once new instantiates the object, the developer receives an object which is ready to be used, no separate call to object-init() required. Is there a good reason why constructors shouldn't do real work? Obviously it could slow allocation time, but that wouldn't be any different if calling a separate method immediately after allocation. Just trying to figure out what gotchas I not currently considering that might have lead to such advice.

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  • WCF with MANY database connections

    - by Jorge Dominguez
    I'm working in the development of an ERP type .Net WinForms application consuming a WCF service. It's to be used by many small companies (in the range of 100-200). Database is SQL Server 2008 and the service will be hosted as a Windows service. Even thought there will be a single DB Server, our customer insists in having separate databases for each company. That is because of stability/support concerns (like DB being damaged or took offline for some reason thus affecting all clients). Concerns coming from previous experiences (not necessarily with same platform). With a single database, connections to the DB would be opened at service start up and pooling used, but, I'm not sure how connections could be managed in a multiple DB scenario: Could a connection to the corresponding DB be opened and closed for each service request? would performance be acceptable? If a connection is opened and maintained for each company accessing the system, what's the practical limit of opened connections (to different databases)? It would be very interesting to hear your opinions and suggestions for this situation. Tanks

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