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  • Is there a good way of displaying required field indicators when using DataAnnotations in MVC 2?

    - by Jeremy Gruenwald
    I've got validation working with DataAnnotations on all my models, but I'd like to display an indicator for required fields on page load. Since I've got all my validation centralized, I'd rather not hard-code indicators in the View. Calling validation on load would show the validation summary. Has anyone found a good way of letting the model determine what's required, but checking it upon rendering the view, similar to Html.ValidationMessageFor?

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  • When is a good time to start thinking about scaling?

    - by Slokun
    I've been designing a site over the past couple days, and been doing some research into different aspects of scaling a site horizontally. If things go as planned, in a few months (years?) I know I'd need to worry about scaling the site up and out, since the resources it would end up consuming would be huge. So, this got me to thinking, when is the best time to start thinking about, and designing for, scalability? If you start too early on, you could easily over complicate your design, and make it impossible to actually build. You could also get too caught up in the details, the architecture, whatever, and wind up getting nothing done. Also, if you do get it working, but the site never takes off, you may have wasted a good chunk of extra effort. On the other hand, you could be saving yourself a ton of effort down the road. Designing it from the ground up to be big would make it much easier later on to let it grow big, with very little rewriting going on. I know for what I'm working on, I've decided to make at least a few choices now on the side of scaling, but I'm not going to do a complete change of thinking to get it to scale completely. Notably, I've redesigned my database from a conventional relational design to one similar to what was suggested on the Reddit site linked below, and I'm going to give memcache a try. So, the basic question, when is a good time to start thinking or worrying about scaling, and what are some good designs, tips, etc. for when doing so? A couple of things I've been reading, for those who are interested: http://www.codinghorror.com/blog/2009/06/scaling-up-vs-scaling-out-hidden-costs.html http://highscalability.com/blog/2010/5/17/7-lessons-learned-while-building-reddit-to-270-million-page.html http://developer.yahoo.com/performance/rules.html

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  • not unique ids in a route in Rails

    - by Victor P
    In a blog in Rails I want to have paths like http://mydomain.com/posts/28383/comments#21 This is the 21st comment of the 28383th post. The 21 is not an unique id, but the pair 28383, #21 is unique. How can I do this in Rails? Do I have to change the routes? the model? I will be very thankful if you can point me in the right direction Thanks

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  • Branching Strategies

    - by Craig H
    The company I work for is starting to have issues with their current branching model, and I was wondering what different kinds of branching strategies the community has been exposed to? Are there any good ones for different situations? What does your company use? What are the advantages and disadvantages of them?

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  • MVC validation error with strongly typed view

    - by Remnant
    I have a simple form that I would like to validate on form submission. Note I have stripped out the html for ease of viewing <%=Html.TextBox("LastName", "")%> //Lastname entry <%=Html.ValidationMessage("LastName")%> <%=Html.TextBox("FirstName", "")%>//Firstname entry <%=Html.ValidationMessage("FirstName")%> <%=Html.DropDownList("JobRole", Model.JobRoleList)%> //Dropdownlist of job roles <% foreach (var record in Model.Courses) // Checkboxes of different courses for user to select { %> <li><label><input type="checkbox" name="Courses" value="<%=record.CourseName%>" /><%= record.CourseName%></label></li> <% } %> On submission of this form I would like to check that both FirstName and LastName are populated (i.e. non-zero length). In my controller I have: public ActionResult Submit(string FirstName, string LastName) { if (FirstName.Trim().Length == 0) ModelState.AddModelError("FirstName", "You must enter a first name"); if (LastName.Trim().Length == 0) ModelState.AddModelError("LastName", "You must enter a first name"); if (ModelState.IsValid) { //Update database + redirect to action } return View(); //If ModelState not valid, return to View and show error messages } Unfortunately, this code logic produces an error that states that no objects are found for JobRole and Courses. If I remove the dropdownlist and checkboxes then all works fine. The issue appears to be that when I return the View the view is expecting objects for the dropwdownlist and checkboxes (which is sensible as that is what is in my View code) How can I overcome this problem? Things I have considered: In my controller I could create a JobRoleList object and Course object to pass to the View so that it has the objects to render. The issue with this is that it will overwrite any dropdownlist / checkbox selections that the user has already made. In the parameters of my controller method Submit I could aslo capture the JobRoleList object and Course object to pass back to the View. Again, not sure this would capture any items the user has already selected. I have done much googling and reading but I cannot find a good answer. When I look at examples in books or online (e.g. Nerddinner) all the validation examples involve simple forms with TextBox inputs and don't seems to show instances with multiple checkboxes and dropdownlists. Have I missed something obvious here? What would be best practice in this situation? Thanks

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  • displaying list of registered user in django-admin

    - by theactiveactor
    My Book model has an author attribute which today is simply a CharField. The value for author should be one of the registered users of my Django site. When creating a new Book object in Django admin, I would like author to be displayed as a combo box showing all registered users. How would I go about achieving this?

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  • NSMutableArray of NSString in CoreData(iPhone

    - by azia
    I have a class, which describe an object for parsing XML. This class contains NSStrings and NSMutableArrays of NSStrings.I want to store parsed data using CoreData. How should I write CoreData model to store such objects if there is no such data type like NSMutableArray? Is there any way?

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  • Many-To-Many Query with Linq-To-NHibernate

    - by rjygraham
    Ok guys (and gals), this one has been driving me nuts all night and I'm turning to your collective wisdom for help. I'm using Fluent Nhibernate and Linq-To-NHibernate as my data access story and I have the following simplified DB structure: CREATE TABLE [dbo].[Classes]( [Id] [bigint] IDENTITY(1,1) NOT NULL, [Name] [nvarchar](100) NOT NULL, [StartDate] [datetime2](7) NOT NULL, [EndDate] [datetime2](7) NOT NULL, CONSTRAINT [PK_Classes] PRIMARY KEY CLUSTERED ( [Id] ASC ) CREATE TABLE [dbo].[Sections]( [Id] [bigint] IDENTITY(1,1) NOT NULL, [ClassId] [bigint] NOT NULL, [InternalCode] [varchar](10) NOT NULL, CONSTRAINT [PK_Sections] PRIMARY KEY CLUSTERED ( [Id] ASC ) CREATE TABLE [dbo].[SectionStudents]( [SectionId] [bigint] NOT NULL, [UserId] [uniqueidentifier] NOT NULL, CONSTRAINT [PK_SectionStudents] PRIMARY KEY CLUSTERED ( [SectionId] ASC, [UserId] ASC ) CREATE TABLE [dbo].[aspnet_Users]( [ApplicationId] [uniqueidentifier] NOT NULL, [UserId] [uniqueidentifier] NOT NULL, [UserName] [nvarchar](256) NOT NULL, [LoweredUserName] [nvarchar](256) NOT NULL, [MobileAlias] [nvarchar](16) NULL, [IsAnonymous] [bit] NOT NULL, [LastActivityDate] [datetime] NOT NULL, PRIMARY KEY NONCLUSTERED ( [UserId] ASC ) I omitted the foreign keys for brevity, but essentially this boils down to: A Class can have many Sections. A Section can belong to only 1 Class but can have many Students. A Student (aspnet_Users) can belong to many Sections. I've setup the corresponding Model classes and Fluent NHibernate Mapping classes, all that is working fine. Here's where I'm getting stuck. I need to write a query which will return the sections a student is enrolled in based on the student's UserId and the dates of the class. Here's what I've tried so far: 1. var sections = (from s in this.Session.Linq<Sections>() where s.Class.StartDate <= DateTime.UtcNow && s.Class.EndDate > DateTime.UtcNow && s.Students.First(f => f.UserId == userId) != null select s); 2. var sections = (from s in this.Session.Linq<Sections>() where s.Class.StartDate <= DateTime.UtcNow && s.Class.EndDate > DateTime.UtcNow && s.Students.Where(w => w.UserId == userId).FirstOrDefault().Id == userId select s); Obviously, 2 above will fail miserably if there are no students matching userId for classes the current date between it's start and end dates...but I just wanted to try. The filters for the Class StartDate and EndDate work fine, but the many-to-many relation with Students is proving to be difficult. Everytime I try running the query I get an ArgumentNullException with the message: Value cannot be null. Parameter name: session I've considered going down the path of making the SectionStudents relation a Model class with a reference to Section and a reference to Student instead of a many-to-many. I'd like to avoid that if I can, and I'm not even sure it would work that way. Thanks in advance to anyone who can help. Ryan

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  • add properties to users google app engine

    - by juanefren
    What is the best way to save a user profile with Google App Engine (Python) ? What I did to solve this problem is create another Model, with a UserProperty, but requesting the profile from the user I have to do something like this: if user: profile = Profile.all().filter('user =', user).fetch(1) if profile: property = s.get().property Any ideas?

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  • What RESTful API would you use for a turn-based game server?

    - by Ross
    How would you model a turn-based game server as a RESTful API? For example, a chess server, where you could play a game of chess against another client of the same API. You would need some way of requesting and negotiating a game with the other client, and some way of playing the individual moves of the game. Is this a good candidate for a REST (RESTful) API? Or should this be modelled a different way?

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  • Asp.Net MVC Not Duplicate forms when Edit/Add

    - by Pino
    When we have anything that requires user input (Eg adding a product to a database) the Edit screen looks the same as the add screen. When using MVC .Net how do you handle this? Do you return the same view? Just adjust the model to reflect the change?

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  • finding ALL cycles in a huge sparse matrix

    - by Andy
    Hi there, First of all I'm quite a Java beginner, so I'm not sure if this is even possible! Basically I have a huge (3+million) data source of relational data (i.e. A is friends with B+C+D, B is friends with D+G+Z (but not A - i.e. unmutual) etc.) and I want to find every cycle within this (not necessarily connected) directed graph. I've found this thread (http://stackoverflow.com/questions/546655/finding-all-cycles-in-graph/549402#549402) which has pointed me to Donald Johnson's (elementary) cycle-finding algorithm which, superficially at least, looks like it'll do what I'm after (I'm going to try when I'm back at work on Tuesday - thought it wouldn't hurt to ask in the meanwhile!). I had a quick scan through the code of the Java implementation of Johnson's algorithm (in that thread) and it looks like a matrix of relations is the first step, so I guess my questions are: a) Is Java capable of handling a 3+million*3+million matrix? (was planning on representing A-friends-with-B by a binary sparse matrix) b) Do I need to find every connected subgraph as my first problem, or will cycle-finding algorithms handle disjoint data? c) Is this actually an appropriate solution for the problem? My understanding of "elementary" cycles is that in the graph below, rather than picking out A-B-C-D-E-F it'll pick out A-B-F, B-C-D etc. but that's not the end of the world given the task. E / \ D---F / \ / \ C---B---A d) If necessary, I can simplify the problem by enforcing mutuality in relations - i.e. A-friends-with-B <== B-friends-with-A, and if really necessary I can maybe cut down the data size, but realistically it is always going to be around the 1mil mark. z) Is this a P or NP task?! Am I biting off more than I can chew? Thanks all, any help appreciated! Andy

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  • VB6's private static in C# ?

    - by blez
    In VB6 there are local static variables that keep their values after the exit of procedure. It's like using public vars but on local block. For example: sub count() static x as integer x = x + 1 end sub After 10 calls, x will be 10. I tried to search the same thing in .NET (and even Java) but there was none. Why? Does it break the OOP model in some way, and is there a way to emulate that.

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  • javascript conflict on accesing DOM

    - by justjoe
    i read this statement from a book i read The Document Object Model or DOM is really not a part of JavaScript but a separate entity existing outside it. Although you can use JavaScript to manipulate DOM objects, other scripting languages may equally well access them too. what is the best way to avoid conflict between javascript and other client-siede scripting language when we have to deal with XMLHTTPRequest object

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  • Error while executing query

    - by iHeartDucks
    I get an error message on this query query = "select count(*) from pgns_game where raw_moves = %s" params = ('a',) total_rows = self.model.objects.raw(query, params) and it says InvalidQuery('Raw query must include the primary key') I am clearly missing something but I don't know what. Any ideas?

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  • [Django] How to post to a facebook page

    - by patrick
    Hi! I need to post a status update of one of my facebook page when I create a model into my django project, but I don't know how to do it using the new facebook graph api: http://github.com/facebook/python-sdk/blob/master/src/facebook.py can you explain to me how to do it? Thanks in advance :)

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  • XML Schema for a .NET type that inherits and implements

    - by John Ruiz
    Hi, Please consider the following three .NET types: I have an interface, an abstract class, and a concrete class. My question is how to write the XML Schema to include the properties from the interface and from the abstract class. public interface IStartable { bool RequiresKey { get; set; } void Start(object key); } public abstract class Vehicle { uint WheelCount { get; set; } } public class Car : Vehicle, IStartable { public bool RequiresKey { get; set; } public string Make { get; set; } publilc string Model { get; set; } public Car() {} public void Start(object key) { // start car with key } } I don't know how to complete this schema: <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace="cars" xmlns="cars" xmlns:c="cars"> <!-- How do I get car to have vehicle's wheelcount AND IStartable's RequiresKey? --> <xs:element name="Car" type="c:Car" /> <xs:complexType name="Car"> <xs:complexContent> <xs:extension base="c:Vehicle"> <xs:group ref=c:CarGroup" /> </xs:extension> </xs:complexContent> </xs:complexType> <xs:group name="CarGroup"> <xs:sequence> <xs:element name="Make" type="xs:token" /> <xs:element name="Model" type="xs:token" /> </xs:sequence> </xs:group> <xs:complexType name="Vehicle"> <xs:sequence> <xs:element name="WheelCount" type="xs:unsignedInt" /> </xs:sequence> </xs:complexType> <xs:complexType name="IStartable"> <xs:sequence> <xs:element name="RequiresKey" type="xs:boolean" /> </xs:sequence> </xs:complexType> </xs:schema>

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  • how to specify a BIGINT in a rails scaffold?

    - by webdestroya
    I am trying to create a model in ruby that uses a BIGINT datatype (as opposed to the INT done by :integer). I have search all over Google, but all I seem to find is "run an SQL statement to alter the table to a BIGINT" - This seems a bit hack-ish to me, so I wanted to know if there was a way to specify a bigint in the ruby system like :big_int or something Any ideas?

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  • Pylons error handling

    - by TJ Huffington
    Hello, I am just getting started with Pylons and am confused as to how to account for exceptions. What is the proper way to error check user input (ensure a correct email address, check that it doesn't yet exist in the database, etc ...)? Should these checks go inside the model classes or somewhere else? Sample code would be great.

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  • Mongrel not using latest deployed code, despite multiple restarts

    - by ming yeow
    What could be the potential reasons why mongrel does not use the latest code in the ~/current branch? The code changes are in the MODELs. The code changes in the CONTROLLERS TAKE EFFECT. I tried the following: god restart app deploying several times manually stopping mongrel cluster, deleting the pid files, and starting them again Anyone has similar experiences? Where could the server be potentially caching the model files?

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