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• Database structure for ecommerce site

  - by imanc

  Hey Guys, I have been tasked with designing an ecommerce solution. The aspect that is causing me the most problems is the database. Currently the site consists of 10+ country based shops each with their own database (all residing on the same mysql instance). For the new site I'd rather all these shop databases be merged into one database so that all tables (products, orders, customers etc.) have a shop_id field. From a programming perspective this seems to make the most sense as we won't have to manage data across multiple databases. Currently the entire site generates about 120k orders a year, but is experiencing fairly heavy growth and we need to design a solution that will scale. In 5 years there may be more than a million orders per year and a database that contains 5 years order history (archiving maybe a solution here). The question is - do we use a single database, or do we keep the database-per-shop structure? I am currently trying to find supporting evidence for either avenue. The company I am designing the solution for prefer the per-shop database structure because they believe it will allow the sites to scale. But my argument is that the shop's database probably won't get that busy over the next few years that they exceed the capacity of a mysql database and a "no expenses spared" hardware set-up. I am wondering if anyone has any advice either way? Does anyone have experience with websites / ecommerce sites that have tables containing millions of records? I know there is probably not a clear answer here, but at what stage do we have too many records or too large table files to have a fast loading site? Also, if anyone has any advice on sources of information - books, websites, etc. where I can do further research, it would be highly appreciated! Cheers, imanc

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• Help with mysql sum and group query and managing results for jquery graph.

  - by Scarface

  I have a system I am trying to design that will retrieve information from a database, so that it can be plotted in a jquery graph. I need to retrieve the information and somehow put it in the necessary coordinates format (for example two coordinates var d = [[1269417600000, 10],[1269504000000, 15]];). My table that I am selecting from is a table that stores user votes with fields: points_id (1=vote up, 2=vote down), user_id, timestamp, topic_id What I need to do is select all the votes and somehow group them into respective days and then sum the difference between 1 votes and 2 votes for each day. I then need to somehow display the data in the appropriate plotting format shown earlier. For example April 1, 4 votes. The data needs to be separated by commas, except the last plot entry, so I am not sure how to approach that. I showed an example below of the kind of thing I need but it is not correct, echo "var d=["; $query=mysql_query( "SELECT *, SUM(IF(points_id = \"1\", 1,0))-SUM(IF([points_id = \"2\", 1,0)) AS 'total' FROM points LEFT JOIN topic ON topic.topic_id=points.topic_id WHERE topic.creator='$user' GROUP by timestamp HAVING certain time interval" ); while ($row=mysql_fetch_assoc($query)){ $timestamp=$row['timestamp']; $votes=$row['total']; echo "[$timestamp,$vote],"; } echo "];";

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• Users Hierarchy Logic

  - by user342944

  Hi guys, I am writing a user security module using SQLServer 2008 so threfore need to design a database accordingly. Formally I had Userinfo table with UserID, Username and ParentID to build a recursion and populated tree to represent hierarchy but now I have following criteria which I need to develop. I have now USERS, ADMINISTRATORS and GROUPS. Each node in the user hierarchy is either a user, administrator or group. User Someone who has login access to my application Administrator A user who may also manage all their child user accounts (and their children etc) This may include creating new users and assigning permissions to those users. There is no limit to the number of administrators in user structure. The higher up in the hierarchy that I go administrators have more child accounts to manage which include other child administrators. Group A user account can be designated as a group. This will be an account which is used to group one or more users together so that they can be manage as a unit. But no one can login to my application using a group account. This is how I want to create structure Super Administrator administrator ------------------------------------------------------------- | | | Manager A Manager B Manager C (adminstrator) (administrator) (administrator) | ----------------------------------------- | | | Employee A Employee B Sales Employees (User) (User) (Group) | ------------------------ | | | Emp C Emp D Emp E (User) (User) (User) Now how to build the table structure to achieve this. Do I need to create Users table alongwith Group table or what? Please guide I would really appreciate.

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• jQuery: select checkbox when upload field is clicked

  - by Arne Stephensson

  I'm working on a CMS. When a user wants to replace an existing thumbnail image, they can upload a replacement, and check a checkbox to certify that they are indeed replacing the image. The checkbox seems necessary because otherwise the form submits a blank value (due to the presence of the upload field with no value) and wipes out the existing image without a replacement image being specified. The problem is that I keep forgetting to manually activate the checkbox and the uploaded image does not actually replace the existing one because without the checkbox being clicked, the receiving PHP file does not (by design) process the incoming filename. I suspect that users will have the same problem and I want to keep this from happening by reducing the number of steps required. One solution would be to check the checkbox with jQuery whenever the upload field is clicked. So why doesn't this work: $('#upload_field').click(function () { if ($('#replace_image').attr('checked',true)) { $('#replace_image').removeAttr('checked'); alert('Unchecked'); } else if ($('#replace_image').attr('checked',false)) { $('#replace_image').attr('checked','checked'); alert('Checked'); } });

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• ContentPresenter within ControlTemplate cannot change attached dependency property

  - by happyclicker

  Why does the following simplified code not set the font-size of the TextBlock to 50? <Window.Resources> <ControlTemplate TargetType="ContentControl" x:Key="Test"> <ContentPresenter TextBlock.FontSize="50" /> </ControlTemplate> </Window.Resources> <Grid> <ContentControl Template="{StaticResource Test}"> <TextBlock>Test should be rendered big</TextBlock> </ContentControl> </Grid> If I change the value of the FontSize property, visual studio shows me the text in the size I want. After compiling or executing the app, the size of the textblock is always reset to its default size. I have also tested various versions with styles and embedded resources but I end always in the situation that I cannot set attached dp's from within a ControlTemplate that contains a ContentPresenter. Is this by design?

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• Entity Framework and WCf

  - by Nihilist

  Hi I am little confused on designing WCf services with EF. When using WCf and EF, where do we draw this line on what properties to return and what not to with the entity. Here is my scenario I have User. Here are the relations. User [1 to many] Address, User [ 1 to many] Email, User [ 1 to many] Phone So now on the webform, on page1 I can edit user information. say I can edit few properties on the user entity and can also edit address, phone, email entities[ like add / delete and update any] On page2, i can only update user properties and nothing related to navigation properties [ address, email, phone]. So when I return the User Entity [ OR DTO] should i be returning the navigation properties too? Or should the client make multiple calls to get navigation properites. Also, how does it go with Save? Like should the client make multiple calls to save user and related entites or just one call to save the graph? Lets say, if I just have a Save(User user) [ where user has all the related entities too] both page1 and page2 will call save and pass me the user. but one page1 i will need a lot more information. but on page2 i just need the user primitive properties. So my question is, where do we draw this line, how do we design theses services ? Is the WCF operation designed on the page and the fields it has ? I am hoping i explained my problem well enough.

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• Using a CMS with an external database

  - by George Reith

  I am looking at building an external site with a CMS, probably Drupal or ExpressionEngine. The problem is that our company already has a membership database that is designed to work with our existing enterprise software. Migrating data from the database manually is not an option as modifications and new data must be accessible in real-time. Because the design of the external database will differ from the CMS's own I have decided the best way forward is to use two databases and force the CMS to use the external to read user information (cannot write to) and a local for everything else the CMS needs to do (read + write). Is this feasible with these Drupal or ExpressionEngine? Ideally I need to be able to use hooks as I do not wan't to modify core CMS files. Sifting through the docs I am not able to find what I would hook into for ether CMS. (Note: I know it is possible, but I want to know if it's feasible). Finally if there is a better way of handling this situation please also chime in. Perhaps there is something at the database level to reference a field or table in an external database? I'm clutching at straws someone can point me in the right direction I'm sure.

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• SIMPLE PHP MVC Framework [closed]

  - by Allen

  I need a simple and basic MVC example to get me started. I don't want to use any of the available packaged frameworks. I am in need of a simple example of a simple PHP MVC framework that would allow, at most, the basic creation of a simple multi-page site. I am asking for a simple example because I learn best from simple real world examples. Big popular frameworks (such as code igniter) are to much for me to even try to understand and any other "simple" example I have found are not well explained or seem a little sketchy in general. I should add that most examples of simple MVC frameworks I see use mod_rewrite (for URL routing) or some other Apache-only method. I run PHP on IIS. I need to be able to understand a basic MVC framework, so that I could develop my own that would allow me to easily extend functionality with classes. I am at the point where I understand basic design patterns and MVC pretty well. I understand them in theory, but when it comes down to actually building a real world, simple, well designed MVC framework in PHP, I'm stuck. Edit: I just want to note that I am looking for a simple example that an experienced programmer could whip up in under an hour. I mean simple as in bare bones simple. I don't want to use any huge frameworks, I am trying to roll my own. I need a decent SIMPLE example to get me going.

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• Sharing a COM port over TCP

  - by guinness

  What would be a simple design pattern for sharing a COM port over TCP to multiple clients? For example, a local GPS device that could transmit co-ordinates to remote hosts in realtime. So I need a program that would open the serial port and accept multiple TCP connections like: class Program { public static void Main(string[] args) { SerialPort sp = new SerialPort("COM4", 19200, Parity.None, 8, StopBits.One); Socket srv = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp); srv.Bind(new IPEndPoint(IPAddress.Any, 8000)); srv.Listen(20); while (true) { Socket soc = srv.Accept(); new Connection(soc); } } } I would then need a class to handle the communication between connected clients, allowing them all to see the data and keeping it synchronized so client commands are received in sequence: class Connection { static object lck = new object(); static List<Connection> cons = new List<Connection>(); public Socket socket; public StreamReader reader; public StreamWriter writer; public Connection(Socket soc) { this.socket = soc; this.reader = new StreamReader(new NetworkStream(soc, false)); this.writer = new StreamWriter(new NetworkStream(soc, true)); new Thread(ClientLoop).Start(); } void ClientLoop() { lock (lck) { connections.Add(this); } while (true) { lock (lck) { string line = reader.ReadLine(); if (String.IsNullOrEmpty(line)) break; foreach (Connection con in cons) con.writer.WriteLine(line); } } lock (lck) { cons.Remove(this); socket.Close(); } } } The problem I'm struggling to resolve is how to facilitate communication between the SerialPort instance and the threads. I'm not certain that the above code is the best way forward, so does anybody have another solution (the simpler the better)?

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• Catching specific vs. generic exceptions in c#

  - by Scott Vercuski

  This question comes from a code analysis run against an object I've created. The analysis says that I should catch a more specific exception type than just the basic Exception. Do you find yourself using just catching the generic Exception or attempting to catch a specific Exception and defaulting to a generic Exception using multiple catch blocks? One of the code chunks in question is below: internal static bool ClearFlags(string connectionString, Guid ID) { bool returnValue = false; SqlConnection dbEngine = new SqlConnection(connectionString); SqlCommand dbCmd = new SqlCommand("ClearFlags", dbEngine); SqlDataAdapter dataAdapter = new SqlDataAdapter(dbCmd); dbCmd.CommandType = CommandType.StoredProcedure; try { dbCmd.Parameters.AddWithValue("@ID", ID.ToString()); dbEngine.Open(); dbCmd.ExecuteNonQuery(); dbEngine.Close(); returnValue = true; } catch (Exception ex) { ErrorHandler(ex); } return returnValue; } Thank you for your advice EDIT: Here is the warning from the code analysis Warning 351 CA1031 : Microsoft.Design : Modify 'ClearFlags(string, Guid)' to catch a more specific exception than 'Exception' or rethrow the exception

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• Error handling in C++, constructors vs. regular methods

  - by Dennis Ritchie

  I have a cheesesales.txt CSV file with all of my recent cheese sales. I want to create a class CheeseSales that can do things like these: CheeseSales sales("cheesesales.txt"); //has no default constructor cout << sales.totalSales() << endl; sales.outputPieChart("piechart.pdf"); The above code assumes that no failures will happen. In reality, failures will take place. In this case, two kinds of failures could occur: Failure in the constructor: The file may not exist, may not have read-permissions, contain invalid/unparsable data, etc. Failure in the regular method: The file may already exist, there may not be write access, too little sales data available to create a pie chart, etc. My question is simply: How would you design this code to handle failures? One idea: Return a bool from the regular method indicating failure. Not sure how to deal with the constructor. How would seasoned C++ coders do these kinds of things?

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• Assembly-wide / root-level styles in WPF class library

  - by WarpedBoard

  I have a C# (2008/.NET 3.5) class library assembly that supports WPF (based on http://dotupdate.wordpress.com/2007/12/05/how-to-add-a-wpf-control-library-template-to-visual-c-express-2008/). I've created several windows, and am now attempting to create a common style set for them. However, as it's a class library (instead of a WPF app), I don't have an app.xaml (and its contained Application & corresponding Application.Resources) in which to store these styles for global access. So: How can I create a top-level set of style definitions that'll be seen by all xaml files in the assembly, given that I do not have app.xaml (see above)? And/or is it possible to add a working app.xaml to a class library? FYI, I did try creating a ResourceDictionary in a ResourceDictionary.xaml file, and include it in each window within a "Window.Resources" block. That turned out to solve the styling of Buttons, etc... but not for the enclosing Window. I can put 'Style="{StaticResource MyWindowStyle}"' in the Window's opening block, and it compiles and shows up in the VS Design window fine, but during actual runtime I get a parse exception (MyWindowStyle could not be found; I'm guessing Visual Studio sees the dictionary included after the line in question, but the CRL does things more sequentially and therefore hasn't loaded the ResourceDictionary yet).

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• How to get at specific HTML elements of a document using C# and Hide them/Show them etc.

  - by LaserBeak

  Basically I want to load a HTML document and using controls such as multiple check boxes which will be programmed to hide, delete or show HTML elements with certain ID's. So I am thinking I would have to set an inline CSS property for visibility to: false on the ones I want to hide or delete them altogether when necessary. I need this so I don't have to edit my Ebay HTML templates in dreamweaver all the time, where I usually have to scroll around messy code and manually delete or add tags and their respective content. Whereas I just want to create one master template in dreamweaver which has all the variations that my products have, since they are all of the same genre with slight changes here and there and I just need to enable and disable the visibility of these variants as required and copy + paste the final html. I haven's used Windows Forms before, but tried doing this in WebForms which I do know a bit. I am able to get the result that I want by wrapping any HTML elements in a <asp:PlaceHolder></asp:PlaceHolder> and just setting that place holders visibility to false after the associated checkbox is checked and a postback occurs, finally I add a checkbox/button control that removes all the checkboxes, including itself etc for final html. But this method seems just like too much pain in the ass as I have to add the placeholder tags around everything that I need control over as ordinary html elements do not run at server, also webforms injects a bunch of Javascript and ViewState data so I don't have clean HTML which I can just copy after viewing the page source. Any tips/code that you can suggest to achieve the desired effect with the least changes required to existing HTML documents? Ideally I would want to load the HTML document in, have a live design preview of it and underneath have a bunch of well labelled checkboxes programmed to hide, delete or show elements with certain ID's. Thanks...

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• Scientific Algorithms that can produce imagery, pseudocode perhaps?

  - by Ross

  Hello, I have a client who are based in the field of mathematics. We are developing, amongst other things, a website. I like to create a mock-up of a drawing tool that an produce some imagery in the background based on some scientific algorithms. The intention being that the may client, later, may create there own. (They use emacs for everything, great client.) I'm look for an answer of where or what to go looking for. Not code specific, pseudocode even, as we can adapt and have not yet settled on a platform. I'm afraid my mathematic stops at the power of two and some trigonometry. Appreciated if they're are any mathematics related students/academics how could enlighten me? What to search for will be accepted? Edit: To summarise/clarify, I want to draw pretty pictures (the design perspective). I want them to have some context (i.e. not just for the sake of pretty images but have some explanation available). In essence I would to create a rendering engine which we can draw the images and we set the style parameters: line, colour, etc... But to pursue this option I want to experiment myself. Thanks Ross

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• DotNetOpeId - Using OpenIdButton for Google Apps

  - by JediPotPie

  I am an ASP.NET newbie and I am trying to design an OpenID/SSO system for an internal web application. The web application is pretty simple and the authentication is currently being managed by a database with usernames and passwords. I want to replace the existing accounts stored in the database with Google Apps accounts. I have downloaded the latest DotNetOpenAuth-3.4.3.10103 package and got the OpenIdRelyingPartyWebForms sample up and running on IIS. I have built my own login page using just a OpenIdButton object that points to a development Google domain. The button seems to work fine in FireFox, at least it is forwarding me to the Google Apps login, but nothing happens when I load the same page in IE. When I click the Google button, nothing happens, zip. The same is true for the Yahoo button in the login.aspx page given in the sample. Here is the .aspx code I am using... <rp:OpenIdButton runat="server" ImageUrl="http://www.google.com/accounts/google_transparent.gif" Text="Login with Google!" ID="googleLoginButton" Identifier="https://www.google.com/accounts/o8/site-xrds?hd=dev.connexcloud.com" />

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• What is the appropriate HTML 5 element for a hero unit/showcase?

  - by deb

  A lot of marketing and content-heavy sites showcase the page's primary content using large text and/or images, sometimes with a slider, containing a call to action for signing up for a service, or downloading an app, etc.. I'm not sure what this design element is called, I got the term hero unit from twitter bootstrap: http://twitter.github.com/bootstrap/components.html#typography I think most of you know what I'm trying to describe... If it's not clear I can add screenshots or links to this question. I looked at a few different sites, and some put this hero unit inside a ASIDE element, others use SECTION, ARTICLE and even HEADER. Using twitter bootstrap as an example again: <header class="jumbotron masthead"> <div class="inner"> <h1>Bootstrap, from Twitter</h1> <p>Simple and flexible HTML, CSS, and Javascript for popular user interface components and interactions.</p> <p class="download-info"> Is HEADER the most appropriate tag for this type of content? Or should I use ASIDE, ARTICLE or SECTION?

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• Why there is no scoped locks for multiple mutexes in C++0x or Boost.Thread?

  - by Vicente Botet Escriba

  C++0x thread library or Boost.thread define non-member variadic template function that lock all lock avoiding dead lock. template <class L1, class L2, class... L3> void lock(L1&, L2&, L3&...); While this function avoid help to deadlock, the standard do not includes the associated scoped lock to write exception safe code. { std::lock(l1,l2); // do some thing // unlock li l2 exception safe } That means that we need to use other mechanism as try-catch block to make exception safe code or define our own scoped lock on multiple mutexes ourselves or even do that { std::lock(l1,l2); std::unique_lock lk1(l1, std::adopted); std::unique_lock lk2(l2, std::adopted); // do some thing // unlock li l2 on destruction of lk1 lk2 } Why the standard doesn't includes a scoped lock on multiple mutexes of the same type, as for example { std::array_unique_lock<std::mutex> lk(l1,l2); // do some thing // unlock l1 l2 on destruction of lk } or tuples of mutexes { std::tuple_unique_lock<std::mutex, std::recursive_mutex> lk(l1,l2); // do some thing // unlock l1 l2 on destruction of lk } Is there something wrong on the design?

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• MySQL " identify storage engine statement"

  - by sammysmall

  This IS NOT a Homework question! While building my current student database project I realized that I may want to identify comprehensive information about a database design in the future. More-so if I am fortunate enough to get a job in this field and were handed a database project how could I break down certain elements for identification... In all of my previous designs I have been using MySQL Community Server (GPL) 5.1.42, I thought (duh) that I was using the MyISAM based on most of my text-book instruction and MySQL 5.0 Reference Manual :: 13 Storage Engines :: 13.1 The MyISAM Storage Engine I determined that this was in fact incorrect for this version and the use of "SHOW ENGINES" at the console... No problem, figured out why they have "versions" the need to pay attention to what version is being used, and the need for a means to determine what I am about to mess up "if" I do not pay attention to detail... Q1. Specifically what statement will identify the version used by someone elses initial database creation? (since I created my own databases I know what version I used) Q2. Specifically what statement will identify the storage engine that the developer used when creating the database. (I specified a particular database in my collection then tried SHOW Engine, did not work, then tried to just get the metadata from one table in that database: mysql SELECT duck_cust, table_type, engine - FROM INFORMATION_SCHEMA.tables - WHERE table_schema = 'tp' - ORDER BY table_type ASC, table_name DESC; as this was not really what I wanted (and did not work) I am looking for some direction from the pros... Q3. (If you really have the inclination to continue helping) If I were to access a database from an earlier/later "version" are there backward/forward compatibility issues for maintaining/updating data between versions? Please and Thank you in advance for your time and efforts! sammysmall

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• WCF data services (OData), query with inheritance limitation?

  - by Mathieu Hétu

  Project: WCF Data service using internally EF4 CTP5 Code-First approach. I configured entities with inheritance (TPH). See previous question on this topic: Previous question about multiple entities- same table The mapping works well, and unit test over EF4 confirms that queries runs smoothly. My entities looks like this: ContactBase (abstract) Customer (inherits from ContactBase), this entity has also several Navigation properties toward other entities Resource (inherits from ContactBase) I have configured a discriminator, so both Customer and Resource map to the same table. Again, everythings works fine on the Ef4 point of view (unit tests all greens!) However, when exposing this DBContext over WCF Data services, I get: - CustomerBases sets exposed (Customers and Resources sets seems hidden, is it by design?) - When I query over Odata on Customers, I get this error: Navigation Properties are not supported on derived entity types. Entity Set 'ContactBases' has a instance of type 'CodeFirstNamespace.Customer', which is an derived entity type and has navigation properties. Please remove all the navigation properties from type 'CodeFirstNamespace.Customer'. Stacktrace: at System.Data.Services.Serializers.SyndicationSerializer.WriteObjectProperties(IExpandedResult expanded, Object customObject, ResourceType resourceType, Uri absoluteUri, String relativeUri, SyndicationItem item, DictionaryContent content, EpmSourcePathSegment currentSourceRoot) at System.Data.Services.Serializers.SyndicationSerializer.WriteEntryElement(IExpandedResult expanded, Object element, ResourceType expectedType, Uri absoluteUri, String relativeUri, SyndicationItem target) at System.Data.Services.Serializers.SyndicationSerializer.<DeferredFeedItems>d__b.MoveNext() at System.ServiceModel.Syndication.Atom10FeedFormatter.WriteItems(XmlWriter writer, IEnumerable`1 items, Uri feedBaseUri) at System.ServiceModel.Syndication.Atom10FeedFormatter.WriteFeedTo(XmlWriter writer, SyndicationFeed feed, Boolean isSourceFeed) at System.ServiceModel.Syndication.Atom10FeedFormatter.WriteFeed(XmlWriter writer) at System.ServiceModel.Syndication.Atom10FeedFormatter.WriteTo(XmlWriter writer) at System.Data.Services.Serializers.SyndicationSerializer.WriteTopLevelElements(IExpandedResult expanded, IEnumerator elements, Boolean hasMoved) at System.Data.Services.Serializers.Serializer.WriteRequest(IEnumerator queryResults, Boolean hasMoved) at System.Data.Services.ResponseBodyWriter.Write(Stream stream) Seems like a limitation of WCF Data services... is it? Not much documentation can be found on the web about WCF Data services (OData) and inheritance specifications. How can I overpass this exception? I need these navigation properties on derived entities, and inheritance seems the only way to provide mapping of 2 entites on the same table with Ef4 CTP5... Any thoughts?

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• How can I cluster short messages [Tweets] based on topic ? [Topic Based Clustering]

  - by Jagira

  Hello, I am planning an application which will make clusters of short messages/tweets based on topics. The number of topics will be limited like Sports [ NBA, NFL, Cricket, Soccer ], Entertainment [ movies, music ] and so on... I can think of two approaches to this Ask for users to tag questions like Stackoverflow does. Users can select tags from a predefined list of tags. Then on server side I will cluster them on based of tags. Pros:- Simple design. Less complexity in code. Cons:- Choices for users will be restricted. Clusters will not be dynamic. If a new event occurs, the predefined tags will miss it. Take the message, delete the stopwords [ predefined in a dictionary ] and apply some clustering algorithm to make a cluster and depending on its popularity, display the cluster. The cluster will be maintained according to its sustained popularity. New messages will be skimmed and assigned to corresponding clusters. Pros:- Dynamic clustering based on the popularity of the event/accident. Cons:- Increased complexity. More server resources required. I would like to know whether there are any other approaches to this problem. Or are there any ways of improving the above mentioned methods? Also suggest some good clustering algorithms.I think "K-Nearest Clustering" algorithm is apt for this situation.

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• How do virtual destructors work?

  - by Prabhu

  Few hours back I was fiddling with a Memory Leak issue and it turned out that I really got some basic stuff about virtual destructors wrong! Let me put explain my class design. class Base { virtual push_elements() {} }; class Derived:public Base { vector<int> x; public: void push_elements(){ for(int i=0;i <5;i++) x.push_back(i); } }; void main() { Base* b = new Derived(); b->push_elements(); delete b; } The bounds checker tool reported a memory leak in the derived class vector. And I figured out that the destructor is not virtual and the derived class destructor is not called. And it surprisingly got fixed when I made the destructor virtual. Isn't the vector deallocated automatically even if the derived class destructor is not called? Is that a quirk in BoundsChecker tool or is my understanding of virtual destructor wrong?

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• Dependency injection in constructors

  - by andre

  Hello everyone. I'm starting a new project and setting up the base to work on. A few questions have risen and I'll probably be asking quite a few in here, hopefully I'll find some answers. First step is to handle dependencies for objects. I've decided to go with the dependency injection design pattern, to which I'm somewhat new, to handle all of this for the application. When actually coding it I came across a problem. If a class has multiple dependencies and you want to pass on multiple dependencies via the constructor (so that they cannot be changed after you instantiate the object). How do you do it without passing an array of dependencies, using call_user_func_array(), eval() or Reflection? This is what i'm looking for: <?php class DI { public function getClass($classname) { if(!$this->pool[$classname]) { # Load dependencies $deps = $this->loadDependencies($classname); # Here is where the magic should happen $instance = new $classname($dep1, $dep2, $dep3); # Add to pool $this->pool[$classname] = $instance; return $instance; } else { return $this->pool[$classname]; } } } Again, I would like to avoid the most costly methods to call the class. Any other suggestions?

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• Magento delete some scripts

  - by Patrik van Dendis

  Hi I use a magento for my e-commerce. I have custom design, but when I show my source code I can see some scripts and css styles after my footer. I want edit it but I dont know where. <!--{%FOOTER_LINK}--> </div> </div> <script type='text/javascript' src='//www.beetailer.com/javascripts/beetailer.js'></script> <style type="text/css"> div.share-buttons {margin-top: 5px; margin-bottom: 2px; height: 28px; vertical-align: middle; text-align: justify} div.share-buttons-fb-like {width: 260px;} div.share-custom-container {width: 260px;} .share-buttons-fb-like .share-custom-container span {width: 260px !important;} iframe.fb_ltr {width: 260px !important;} div.top-container {margin-bottom: 0px; text-align: justify} .header-container .top-container {margin-bottom: 0px; text-align: justify} .header-container {margin-bottom: 0px;} div.share-buttons-og { margin-right: 5px !important;} .og-want {margin-top: 2px !important;} .og-own {margin-top: 2px !important;} </style>

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• Reverse geocode street name and city as text

  - by Taylor Satula

  Hello, I have been having some trouble finding a good way to output just the street name and city as text (Infinite Loop, Cupertino shown here) that can be displayed in my iPhone app. This needs to be able to dynamically change as you change streets and city. I don't have the slightest idea of how to do this, I hope someone can help. I have attached a very rough image of what I am trying to acheave. I have found this (http://code.google.com/apis/maps/documentation/javascript/services.html#Geocoding) for google maps about how to reverse geocode using javascript, but what I do not understand is how this would be done in a iPhone development setting. I work in web design and I see how it would be done in HTML but I am very new to iPhone development and don't have the slightest clue of how it would be done here. If someone could spell out how to do this I would be extremely grateful. I cannot seem to find what I am looking for by searching Google. Reference picture: http://www.threepixeldrift.com/images/deep-storage/reversegeocodeiphoneapp.jpg

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• Need help tuning a SQL statement

  - by jeffself

  I've got a table that has two fields (custno and custno2) that need to be searched from a query. I didn't design this table, so don't scream at me. :-) I need to find all records where either the custno or custno2 matches the value returned from a query on the same table based on a titleno. In other words, the user types in 1234 for the titleno. My query searches the table to find the custno associated with the titleno. It also looks for the custno2 for that titleno. Then it needs to do a search on the same table for all other records that have either the custno or custno2 returned in the previous search in the custno or custno2 fields for those other records. Here is what I've come up with: SELECT BILLYR, BILLNO, TITLENO, VINID, TAXPAID, DUEDATE, DATEPIF, PROPDESC FROM TRCDBA.BILLSPAID WHERE CUSTNO IN (select custno from trcdba.billspaid where titleno = '1234' union select custno2 from trcdba.billspaid where titleno = '1234' and custno2 != '') OR CUSTNO2 IN (select custno from trcdba.billspaid where titleno = '1234' union select custno2 from trcdba.billspaid where titleno = '1234' and custno2 != '') The query takes about 5-10 seconds to return data. Can it be rewritten to work faster?

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