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• Timestamps and Intervals: NUMTOYMINTERVAL SYSTDATE CALCULATION SQL QUERY

  - by MeachamRob

  I am working on a homework problem, I'm close but need some help with a data conversion I think. Or sysdate - start_date calculation The question is: Using the EX schema, write a SELECT statement that retrieves the date_id and start_date from the Date_Sample table (format below), followed by a column named Years_and_Months_Since_Start that uses an interval function to retrieve the number of years and months that have elapsed between the start_date and the sysdate. (Your values will vary based on the date you do this lab.) Display only the records with start dates having the month and day equal to Feb 28 (of any year). DATE_ID START_DATE YEARS_AND_MONTHS_SINCE_START 2 Sunday , February 28, 1999 13-8 4 Monday , February 28, 2005 7-8 5 Tuesday , February 28, 2006 6-8 Our EX schema that refers to this question is simply a Date_Sample Table with two columns: DATE_ID NUMBER NOT Null START_DATE DATE I Have written this code: SELECT date_id, TO_CHAR(start_date, 'Day, MONTH DD, YYYY') AS start_date , NUMTOYMINTERVAL((SYSDATE - start_date), 'YEAR') AS years_and_months_since_start FROM date_sample WHERE TO_CHAR(start_date, 'MM/DD') = '02/28'; But my Years and months since start column is not working properly. It's getting very high numbers for years and months when the date calculated is from 1999-ish. ie, it should be 13-8 and I'm getting 5027-2 so I know it's not correct. I used NUMTOYMINTERVAL, which should be correct, but don't think the sysdate-start_date is working. Data Type for start_date is simply date. I tried ROUND but maybe need some help to get it right. Something is wrong with my calculation and trying to figure out how to get the correct interval there. Not sure if I have provided enough information to everyone but I will let you know if I figure it out before you do. It's a question from Murach's Oracle and SQL/PL book, chapter 17 if anyone else is trying to learn that chapter. Page 559.

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• What is jQuery for Document.createElementNS()?

  - by C.W.Holeman II

  What is jQuery for Document.createElementNS()? function emleGraphicToSvg(aGraphicNode) { var lu = function luf(aPrefix){ switch (aPrefix){ case 'xhtml': return 'http://www.w3.org/1999/xhtml'; case 'math': return 'http://www.w3.org/1998/Math/MathML'; case 'svg': return 'http://www.w3.org/2000/svg'; } return ''; }; var svg = document.evaluate("svg:svg", aGraphicNode, lu, XPathResult.FIRST_ORDERED_NODE_TYPE, null). singleNodeValue; $(svg).children().remove(); rect = document.createElementNS(lu('svg'), "rect"); rect.setAttribute("x", "35"); rect.setAttribute("y", "25"); rect.setAttribute("width", "200"); rect.setAttribute("height", "50"); rect.setAttribute("class", "emleGraphicOutline"); svg.appendChild(rect); } The code is a simplified fragment from Emle - Electronic Mathematics Laboratory Equipment JavaScript file emle_lab.js. The Look-Up-Function, luf(), maps a complete reference to a shorten name for the namespace in the XPath string and createElementNS(). The existing svg:svg is located, removed and replaced by a new rectangle.

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• Oracle Insert via Select from multiple tables where one table may not have a row

  - by Mikezx6r

  I have a number of code value tables that contain a code and a description with a Long id. I now want to create an entry for an Account Type that references a number of codes, so I have something like this: insert into account_type_standard (account_type_Standard_id, tax_status_id, recipient_id) ( select account_type_standard_seq.nextval, ts.tax_status_id, r.recipient_id from tax_status ts, recipient r where ts.tax_status_code = ? and r.recipient_code = ?) This retrieves the appropriate values from the tax_status and recipient tables if a match is found for their respective codes. Unfortunately, recipient_code is nullable, and therefore the ? substitution value could be null. Of course, the implicit join doesn't return a row, so a row doesn't get inserted into my table. I've tried using NVL on the ? and on the r.recipient_id. I've tried to force an outer join on the r.recipient_code = ? by adding (+), but it's not an explicit join, so Oracle still didn't add another row. Anyone know of a way of doing this? I can obviously modify the statement so that I do the lookup of the recipient_id externally, and have a ? instead of r.recipient_id, and don't select from the recipient table at all, but I'd prefer to do all this in 1 SQL statement.

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• xpath php attributes not working?

  - by Jared

  Getting this error Call to a member function attributes() on a non-object I have found multiple answers to this on SO, but none of them seem to solve my problem? Here is the XML: <Routes> <Route type="source" name="incoming"> </Route> <Routes> Here is the PHP: $doc = new SimpleXMLElement('routingConfig.xml', null, true); class traverseXML { function getData() { global $doc; $routeCount = count($doc -> xpath("Route")); //this value returns correctly $routeArr = array(); for ($i = 1; $i <= $routeCount; $i++) { $name = $doc -> Route[$i] -> attributes() -> name; array_push($routeArr, $name); } return $routeArr; } } $traverseXML = new traverseXML; var_dump($traverseXML -> getData()); I understand what the error means, but how is it a non-object? How do I return the name attribute of Routes/Route[1] ?

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• How to defer execution of an Event on each item in a collection until iteration of collection is com

  - by Metro Smurf

  Of Note: This is more of a curiosity question than anything else. Given a List<Window> where each window has an event attached to the Close Event which removes the window from the collection, how could you use delegates / events to defer the execution of the Close Event until the collection has been iterated? For example: public class Foo { private List<Window> OpenedWindows { get; set; } public Foo() { OpenedWindows = new List<Window>(); } public void AddWindow( Window win ) { win.Closed += OnWindowClosed; OpenedWindows.Add( win ); } void OnWindowClosed( object sender, EventArgs e ) { var win = sender as Window; if( win != null ) { OpenedWindows.Remove( win ); } } void CloseAllWindows() { // obviously will not work because we can't // remove items as we iterate the collection // (the close event removes the window from the collection) OpenedWindows.ForEach( x => x.Close() ); // works fine, but would like to know how to do // this with delegates / events. while( OpenedWindows.Any() ) { OpenedWindows[0].Close(); } } } Specifically, within the CloseAllWindows() method, how could you iterate the collection to call the close event, but defer the event being raised until the collection has been completely iterated?

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• .NET ServiceInstaller get too much time for uninstall services

  - by rodnower

  Hello, we have some Setup Project wrote in Visual Studio 2008 in C# that installs and uninstalls services with ServiceInstaller class. When I install the services this don't get too much time, but when I uninstall with following code the process for each service get few seconds (and we have many services): ServiceInstaller si = new ServiceInstaler(); string path = string.Format("/assemblypath={0}", strServiceExecutablePath); string[] cmdline = { path }; InstallContext context = new InstallContext(string.Empty, cmdline); si.Context = context; si.ServiceName = strServiceName; si.Uninstall(null); Some one know why? Here I want to ask some related question. What difference between working of: InstallUtill /u exePath when it uninstall service and: sc delete serviceName And why when I delete some record from registry from CurrentControlSet\services I still see the service in services.msc but with: <Failed to read description. Error code:2 In description? From where I need to delete service manually for delete it complitely? Thank you for ahead.

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• Calling a network State check from other activities

  - by Laurent

  I realize this question has been answered before but couldn't find an answer that deals with my specific case. I want to create a class called "InternetConnectionChecks" that will handle checking a network state and http timeouts. I'll call the methods twice in the app (once at the beginning to get data from a server, and once at the end to send user orders to the server). For good form I'd like to put all these methods in a single class rather than copy/paste at different points in my code. To check the network state, I'm using ConnectivityManager; thing is, getSystemService requires a class that extends Activity. package arbuckle.app; import android.app.Activity; import android.app.Service; import android.content.Context; import android.net.ConnectivityManager; import android.net.NetworkInfo; public class InternetConnectionChecks extends Activity { public boolean isNetworkAvailable(){ ConnectivityManager connectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo(); if ((activeNetworkInfo != null)&&(activeNetworkInfo.isConnected())){ return true; }else{ return false; } } } QUESTION: if I call the method isNetworkAvailable from another activity, am I: - going to hit up serious errors. - violating good coding form? *If this isn't the right way to do things, can you point me in the right direction to set up a separate class I can call on to check internet connection? Thanks everyone!

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• Merging two arrays in PHP

  - by Industrial

  Hi everyone, I am trying to create a new array from two current arrays. Tried array_merge, but it will not give me what I want. $array1 is a list of keys that I pass to a function. $array2 holds the results from that function, but doesn't contain any non-available resuls for keys. So, I want to make sure that all requested keys comes out with 'null':ed values, as according to the shown $result array. It goes a little something like this: $array1 = array('item1', 'item2', 'item3', 'item4'); $array2 = array( 'item1' => 'value1', 'item2' => 'value2', 'item3' => 'value3' ); Here's the result I want: $result = array( 'item1' => 'value1', 'item2' => 'value2', 'item3' => 'value3', 'item4' => '' ); It can be done this way, but I don't think that it's a good solution - I really don't like to take the easy way out and suppress PHP errors by adding @:s in the code. This sample would obviously throw errors since 'item4' is not in $array2, based on the example. foreach ($keys as $k => $v){ @$array[$v] = $items[$v]; } So, what's the fastest (performance-wise) way to accomplish the same result?

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• Help converting subquery to query with joins

  - by Tim

  I'm stuck on a query with a join. The client's site is running mysql4, so a subquery isn't an option. My attempts to rewrite using a join aren't going too well. I need to select all of the contractors listed in the contractors table who are not in the contractors2label table with a given label ID & county ID. Yet, they might be listed in contractors2label with other label and county IDs. Table: contractors cID (primary, autonumber) company (varchar) ...etc... Table: contractors2label cID labelID countyID psID This query with a subquery works: SELECT company, contractors.cID FROM contractors WHERE contractors.complete = 1 AND contractors.archived = 0 AND contractors.cID NOT IN ( SELECT contractors2label.cID FROM contractors2label WHERE labelID <> 1 AND countyID <> 1 ) I thought this query with a join would be the equivalent, but it returns no results. A manual scan of the data shows I should get 34 rows, which is what the subquery above returns. SELECT company, contractors.cID FROM contractors LEFT OUTER JOIN contractors2label ON contractors.cID = contractors2label.cID WHERE contractors.complete = 1 AND contractors.archived = 0 AND contractors2label.labelID <> 1 AND contractors2label.countyID <> 1 AND contractors2label.cID IS NULL

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• Prolog, check if term is power of 2

  - by Riku

  i have written following code, which should work with my logic, but it does not. I should check if given term is power of two. For example s(s(s(nul))) should return false, s(s(s(s(nul))) should return true. substractWhileY(X,0,rezult). substractWhileY(s(X),Y,rezult):- Y > 0, number is 1, substractWhileY(X,Y - number, rezult). degreeOftwo(X):- substractWhileY(X,2,rezult), pagalba(X, 2, rezult). calculateAnswer(X, currentCounter, currentValue):- currentCounter is currentCounter * 2, substractWhileY(currentValue, currentCounter , rezult), rezult\= null, calculateAnswer(X, currentCounter , rezult). My idea was to check if given therm is degree of any two and if it is not than it is not the degree of two. With numbers it should work like this. For example i give number 8. First time it checks if 8 - 2 = 0. second time if 8 - 4 = 0. third time if 8 - 8 = 0. so the 8 id power of two. Maybe other solution would work better, so thanks for any help.

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• [FLEX] Images won't dynamically refresh

  - by Bridget

  I am writing a Flex application to receive xml from an httpservice. That works because I can populate a datagrid with the information. The xml sends image pathnames. A combobox sends a new HttpService call onChange. This repopulates the datagrid and puts new images in the folder that flex is accessing. I want to dynamically change the image without changing the pathname of the image. <mx:Canvas id="borderCanvas"><mx:Canvas id="dropCanvas"> <mx:Tile id="adTile"><mx:Image></mx:Image> </mx:Tile></mx:Canvas></mx:Canvas> This is my component. I assign my Image sources using this code: var i:Number = 0; while ( i <= dg_conads.rowCount){ var img:Image = new Image(); img.source = null; img.source = imageSource+i+".jpg"; adTile.addChild(img); i++; } My biggest problem is that the images are not refreshing. I get the same image even though I've prevented caching from the HTML wrapper and the ASP.Net website. The image automatically loads in the folder and refreshes in the folder but I can't get the image to refresh in the application. I've tried removeAllChildren(); delete(adTile.getChildAt(0)); and neither worked.

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• Silverlight logging out causes "Object reference not set to an instance"

  - by Alex

  I am using the Silverlight 4 Business Application Template. I've created a DomainDataSource in XAML like so: <riaControls:DomainDataSource x:Name="LogData" QueryName="GetLogs" AutoLoad="True" LoadSize="20" > <riaControls:DomainDataSource.DomainContext> <local:AdminDomainContext /> </riaControls:DomainDataSource.DomainContext> <riaControls:DomainDataSource.QueryParameters> <riaControls:Parameter ParameterName="UserLoginID" Value="{Binding Path=User.UserLoginID, Source={StaticResource WebContext}}" /> </riaControls:DomainDataSource.QueryParameters> </riaControls:DomainDataSource> The problem I'm experiencing is that whenever I log out, I get: Load operation failed for query 'GetLogs'. Object reference not set to an instance of an object. I assume that because I've logged out, User.UserLoginID is now null and is causing the exception. So... anybody know a good way for me to solve this? I don't really want to set the QueryParameter programmatically.

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• Windows Form UserControl design time properties

  - by Raffaeu

  I am struggling with a UserControl. I have a UserControl that represent a Pager and it has a Presenter object property exposed in this way: [Browsable(false)] [DesignSerializationAttribute(DesignSerializationAttribute.Hidden)] public object Presenter { get; set; } The code itself works as I can drag and drop a control into a Windows From without having Visual Studio initializing this property. Now, because in the Load event of this control I call a method of the Presenter that at run-time is null ... I have introduced this additional code: public override void OnLoad(...) { if (this.DesignMode) { base.OnLoad(e); return; } presenter.OnViewReady(); } Now, every time I open a Window that contains this UserControl, Visual Studio modifies the Windows designer code. So, as soon as I open it, VS ask me if I want to save it ... and of course, if I add a control to the Window, it doesn't keep the changes ... As soon as I remove the UserControl Pager the problem disappears ... How should I tackle that in the proper way? I just don't want that the presenter property is initialized at design time as it is injected at runtime ...

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• Cannot understand the behaviour of dotnet compiler while instantiating a class thru interface(C#)

  - by Newbie

  I have a class that impelemnts an interface. The interface is public interface IRiskFactory { void StartService(); void StopService(); } The class that implements the interface is public class RiskFactoryService : IRiskFactory { } Now I have a console application and one window service. From the console application if I write the following code static void Main(string[] args) { IRiskFactory objIRiskFactory = new RiskFactoryService(); objIRiskFactory.StartService(); Console.ReadLine(); objIRiskFactory.StopService(); } It is working fine. However, when I mwrite the same piece of code in Window service public partial class RiskFactoryService : ServiceBase { IRiskFactory objIRiskFactory = null; public RiskFactoryService() { InitializeComponent(); objIRiskFactory = new RiskFactoryService(); <- ERROR } /// <summary> /// Starts the service /// </summary> /// <param name="args"></param> protected override void OnStart(string[] args) { objIRiskFactory.StartService(); } /// <summary> /// Stops the service /// </summary> protected override void OnStop() { objIRiskFactory.StopService(); } } It throws error: Cannot implicitly convert type 'RiskFactoryService' to 'IRiskFactory'. An explicit conversion exists (are you missing a cast?) When I type casted to the interface type, it started working objIRiskFactory = (IRiskFactory)new RiskFactoryService(); My question is why so? Thanks.(C#)

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• Passing $_GET or $_POST data to PHP script that is run with wget

  - by Matt

  Hello, I have the following line of PHP code which works great: exec( 'wget http://www.mydomain.com/u1.php /dev/null &' ); u1.php acts to do various types of maintenance on my server and the above command makes it happen in the background. No problems there. But I need to pass variable data to u1.php before it's executed. I'd like to pass POST data preferably, but could accommodate GET or SESSION data if POST isn't an option. Basically the type of data being passed is user-specific and will vary depending on who is logged in to the site and triggering the above code. I've tried adding the GET data to the end of the URL and that didn't work. So how else might I be able to send the data to u1.php? POST data preferred, SESSION data would work as well (but I tried this and it didn't pick up the logged in user's session data). GET would be a last resort. Thanks!

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• Stopping process in /etc/inittab kills spawned process. Doesn't happen in rc.local.

  - by Paul

  Hi, I'm trying to execute a firmware upgrade while my programming is running in inittab. My program will run 2 commands. One to extract the installer script from the tarball and the other to execute the installer script. In my code I'm using the system() function call. These are the 2 command strings below, system ( "tar zvxf tarball.tar.gz -C / installer.sh 2>&1" ); system( "nohup installer.sh tarball >/dev/null 2>&1 &" ); The installer script requires the tarball to be an argument. I've tried using sudo but i still have the same problem. I've tried nohup with no success. The installer script has to kill my program when doing the firmware upgrade but the installer script will stay alive. If my program is run from the command line or rc.local, on my target device, my upgrade works fine, i.e. when my program is killed my installer script continues. But I need to run my program from /etc/inittab so it can respawn if it dies. To stop my program in inittab the installer script will hash it out and execute "telinit q". This is where my program dies (but thats what I want it to do), but it also kills my installer script. Does anyone know why this is happening and what can I do to solve it? Thanks in advance.

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• What is a good "Error Checking" Pattern (Java)?

  - by Jack

  I'll explain what I mean by input error checking. Say you have a function doSomething(x). If the function completes successfully doSomething does something and returns nothing. However, if there are errors I'd like to be notified. That is what I mean by error checking. I'm looking for, in general, the best way to check for errors. I've thought of the following solutions, each with a potential problem. Flag error checking. If doSomething(x) completes successfully return null. Otherwise, it returns a boolean or an error string. Problem: Side effects. Throwing an exception. Throw an exception if doSomething(x) encounters an error. Problem: If you are performing error checking for parameters only, throwing an IllegalArgumentExceptionseems inappropriate. Validating input prior to function call. If the error checking is only meant for the parameters of the function, then you can call a validator function before calling the doSomething(x) function. Problem: What if a client of the class forgets to call the validator function before calling doSomething(x)? I often encounter this problem and any help or a point in the right direction would be much appreciated.

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• Jasper Reports and iReport issue

  - by William

  I am having an issue with JasperReports I can not solve. I am using Eclipse, OpenReports 3.2 and IReport 3.7 The issue I am having is that the report does nothing. When I preview the report in IReport I can at least get a "Document has no pages" message but when I try to open it using OpenReports it doesn't do anything. I get the open reports header and the copyright message but nothing between them. I was able to track it down to line 150 in ReportRunAction.java in OpenReports. That line is: jasperPrint = jasperEngine.fillReport(reportInput); At least that is the line the page dies on. It trips the catch block that the line is inside of but the error is empty. When I try to print the description it is null. I can't swear that the issue isn't that parameter. Through looking around all I have been able to find is something about how the report needs to be compiled with the same version of the jasperreports.jar that OpenReports uses. I have no idea how to tell if/what version of jasper reports is being bundled into the .jasper file though. Is that my problem? If so how do I tell/set the version of the jar that gets bundled? If not; help!

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• zend_db and join

  - by premtemp

  Hello, I am trying to understand how to use Zend_DB in my program but I have some problem. The class below (DatabaseService) work when I pass it a simple query. However, if I pass it it query with a join clause my page just hangs and not error is return. I cut and paste the qry in a query browesr and it is valid Any help would be great $SQL = "select name from mytable" $db = new DatabaseService($dbinfo) $db ->fetchall($SQL ) // works ----------------------------------------------------------- $SQL = "select count(*) as cnt from EndPoints join CallID on EndPoints.`CallID` = CallID.CallID where EndPoints.LastRegister >= '2010-04-21 00:00:01' and EndPoints.LastRegister <= '2010-04-21 23:59:59' " $db = new DatabaseService($dbinfo) $db ->fetchall($SQL ) // DOES NO WORK class DatabaseService { function DatabaseService($dbinfo,$dbname="") { try { $dbConfig = array( 'host' => $this->host, 'username' => $this->username, 'password' => $password, 'dbname' => $this->dbname ); $this->db = Zend_Db::factory($this->adapter, $dbConfig); Zend_Db_Table::setDefaultAdapter($this->db); } catch(Zend_Exception $e) { $this->error = $e->getMessage(); Helper::log($this->error); return false; } } public function connnect() { if($this->db !=null) { try { $this->db->getConnection(); return true; } catch (Zend_Exception $e) { $err = "FAILED ::".$e->getMessage()." <br />"; } } return false; } public function fetchall($sql) { $res= $this->db->fetchAll($sql); return $res; } }

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• How to use App.Xaml's ResourseDictionaries with own entry point

  - by Polaris

  Hello friends. I created some logic for singleInstance application and I must to use my own entry point (not App.xaml) for Application. I have some styles in App.xaml which now is not working. How can I use this ResourceDictionaries from my App.xaml for entire project in my situation? My class for manage Application Startup public class SingleInstanceManager : WindowsFormsApplicationBase { App app; public SingleInstanceManager() { this.IsSingleInstance = true; } protected override bool OnStartup(Microsoft.VisualBasic.ApplicationServices.StartupEventArgs e) { try { // First time app is launched app = new App(); App.Current.Properties["rcID"] = e.CommandLine; //IntroLibrary.OpenDocumentFromNotify(); app.Run(); return false; } catch (Exception ex) { MessageBox.Show(ex.Message); return false; } } protected override void OnStartupNextInstance(StartupNextInstanceEventArgs eventArgs) { // Subsequent launches base.OnStartupNextInstance(eventArgs); Intro win = (Intro)app.MainWindow; if (eventArgs != null) { App.Current.Properties["rcID"] = eventArgs.CommandLine[0]; } IntroLibrary.OpenDocumentFromNotify(); app.Activate(); } } and my own Entry Point: public class EntryPoint { [STAThread] public static void Main(string[] args) { SingleInstanceManager manager = new SingleInstanceManager(); manager.Run(args); } } And my App.Xaml code behind: public partial class App : Application { protected override void OnStartup(System.Windows.StartupEventArgs e) { base.OnStartup(e); // Create and show the application's main window Intro window = new Intro(); window.Show(); } public void Activate() { // Reactivate application's main window this.MainWindow.Activate(); } } And my App.xaml has some code which decribe ResourceDictionaries which doesnt work. Why?

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• How good idea is it to use code contracts in Visual Studio 2010 Professional (ie. no static checking

  - by Lasse V. Karlsen

  I create class libraries, some which are used by others around the world, and now that I'm starting to use Visual Studio 2010 I'm wondering how good idea it is for me to switch to using code contracts, instead of regular old-style if-statements. ie. instead of this: if (String.IsNullOrWhiteSpace(fileName)) throw new ArgumentNullException("fileName"); (yes, I know, if it is whitespace, it isn't strictly null) use this: Contract.Requires(!String.IsNullOrWhiteSpace(fileName)); The reason I'm asking is that I know that the static checker is not available to me, so I'm a bit nervous about some assumptions that I make, that the compiler cannot verify. This might lead to the class library not compiling for someone that downloads it, when they have the static checker. This, coupled with the fact that I cannot even reproduce the problem, would make it tiresome to fix, and I would gather that it doesn't speak volumes to the quality of my class library if it seemingly doesn't even compile out of the box. So I have a few questions: Is the static checker on by default if you have access to it? Or is there a setting I need to switch on in the class library (and since I don't have the static checker, I won't) Are my fears unwarranted? Is the above scenario a real problem? Any advice would be welcome.

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• Stable/repeatable random sort (MySQL, Rails)

  - by Matt Rogish

  I'd like to paginate through a randomly sorted list of ActiveRecord models (rows from MySQL database). However, this randomization needs to persist on a per-session basis, so that other people that visit the website also receive a random, paginate-able list of records. Let's say there are enough entities (tens of thousands) that storing the randomly sorted ID values in either the session or a cookie is too large, so I must temporarily persist it in some other way (MySQL, file, etc.). Initially I thought I could create a function based on the session ID and the page ID (returning the object IDs for that page) however since the object ID values in MySQL are not sequential (there are gaps), that seemed to fall apart as I was poking at it. The nice thing is that it would require no/minimal storage but the downsides are that it is likely pretty complex to implement and probably CPU intensive. My feeling is I should create an intersection table, something like: random_sorts( sort_id, created_at, user_id NULL if guest) random_sort_items( sort_id, item_id, position ) And then simply store the 'sort_id' in the session. Then, I can paginate the random_sorts WHERE sort_id = n ORDER BY position LIMIT... as usual. Of course, I'd have to put some sort of a reaper in there to remove them after some period of inactivity (based on random_sorts.created_at). Unfortunately, I'd have to invalidate the sort as new objects were created (and/or old objects being removed, although deletion is very rare). And, as load increases the size/performance of this table (even properly indexed) drops. It seems like this ought to be a solved problem but I can't find any rails plugins that do this... Any ideas? Thanks!!

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• fgets throwing unhandled exception while parsing stl

  - by user3478400

  I am new to c++, I am trying to parse a stl file which is of about 64MB and has about ~18K lines in it. The code works fine for first few 100 lines but then fgets throws following exception: "Unhandled exception at 0x77B0BAC5 (ntdll.dll) in STLparser.exe: 0xC0000024: There is a mismatch between the type of object required by the requested operation and the type of object that is specified in the request." I have checked manually the line for which fgets throws exception, there is nothing out of ordinary there. I am out of options for now. Any help to fix this issue will be greatly appreciated. ================CODE========================== #include<fstream> #include<iostream> #include"ParseString.h" #include"Vectors.h" using namespace std; int main(void) { //Define variables FILE *file; char *line = new char; parsestring oneline; int n_Vols = 0, n_Elms = 0, n_nods = -1, E = 0; Nod *nodes = new Nod(); Nod dummy; Elm *elements = new Elm(); int mycounter = 0; //Open file fopen_s(&file, "sample.stl", "r"); while (fgets(line, 1024, file) != NULL) //**********Getting Error Here************* { // populate required data } fclose(file); printf("%d,%d,%d", n_Vols, n_Elms, n_nods); getchar(); return 0; } ===================When broken, execution resumes at this function (not my function, something internal) void __cdecl _unlock ( int locknum ) { /* * leave the critical section. */ LeaveCriticalSection( _locktable[locknum].lock ); }

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• PHP 5.3 and interface \ArrayAccess

  - by Jakub Lédl

  I'm now working on a project and I have one class that implements the ArrayAccess interface. Howewer, I'm getting an error that says that my implementation: must be compatible with that of ArrayAccess::offsetSet(). My implementation looks like this: public function offsetSet($offset, $value) { if (!is_string($offset)) { throw new \LogicException("..."); } $this->params[$offset] = $value; } So, to me it looks like my implementation is correct. Any idea what is wrong? Thanks very much! The class look like this: class HttpRequest implements \ArrayAccess { // tons of private variables, methods for working // with current http request etc. Really nothing that // could interfere with that interface. // ArrayAccess implementation public function offsetExists($offset) { return isset ($this->params[$offset]); } public function offsetGet($offset) { return isset ($this->params[$offset]) ? $this->params[$offset] : NULL; } public function offsetSet($offset, $value) { if (!is_string($offset)) { throw new \LogicException("You can only assing to params using specified key."); } $this->params[$offset] = $value; } public function offsetUnset($offset) { unset ($this->params[$offset]); } }

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• Segmentation Fault

  - by Biranchi

  Hi All, I have the following piece of code for getting the hostname and IP address, #include <stdlib.h> #include <stdio.h> #include <netdb.h> /* This is the header file needed for gethostbyname() */ #include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> int main(int argc, char *argv[]) { struct hostent *he; if (argc!=2){ printf("Usage: %s <hostname>\n",argv[0]); exit(-1); } if ((he=gethostbyname(argv[1]))==NULL){ printf("gethostbyname() error\n"); exit(-1); } printf("Hostname : %s\n",he->h_name); /* prints the hostname */ printf("IP Address: %s\n",inet_ntoa(*((struct in_addr *)he->h_addr))); /* prints IP address */ } but i am getting a warning and segmentation fault as host.c: In function ‘main’: host.c:24: warning: format ‘%s’ expects type ‘char *’, but argument 2 has type ‘int’ What is the error in the code ?? Thanks

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