Search Results

Search found 59569 results on 2383 pages for 'data theory'.

Page 379/2383 | < Previous Page | 375 376 377 378 379 380 381 382 383 384 385 386  | Next Page >

  • Avoid loading unnecessary data from db into objects (web pages)

    - by GmGr
    Really newbie question coming up. Is there a standard (or good) way to deal with not needing all of the information that a database table contains loaded into every associated object. I'm thinking in the context of web pages where you're only going to use the objects to build a single page rather than an application with longer lived objects. For example, lets say you have an Article table containing id, title, author, date, summary and fullContents fields. You don't need the fullContents to be loaded into the associated objects if you're just showing a page containing a list of articles with their summaries. On the other hand if you're displaying a specific article you might want every field loaded for that one article and maybe just the titles for the other articles (e.g. for display in a recent articles sidebar). Some techniques I can think of: Don't worry about it, just load everything from the database every time. Have several different, possibly inherited, classes for each table and create the appropriate one for the situation (e.g. SummaryArticle, FullArticle). Use one class but set unused properties to null at creation if that field is not needed and be careful. Give the objects access to the database so they can load some fields on demand. Something else? All of the above seem to have fairly major disadvantages. I'm fairly new to programming, very new to OOP and totally new to databases so I might be completely missing the obvious answer here. :)

    Read the article

  • Asp.net mvc small amount data storage

    - by Trimack
    Hi there, I am writing some learning tests (i.e. what's the answer for...; choose correct options...). Now my question is, how should I store them. SQL db seems quite an overkill, but I really don't know what would be the best choice if I wanted to select random subset of questions etc. Perhaps some simple xml files? Thanks for advice.

    Read the article

  • Is a base class with shared fields and functions good design

    - by eych
    I've got a BaseDataClass with shared fields and functions Protected Shared dbase as SqlDatabase Protected Shared dbCommand as DBCommand ... //also have a sync object used by the derived classes for Synclock'ing Protected Shared ReadOnly syncObj As Object = New Object() Protected Shared Sub Init() //initializes fields, sets connections Protected Shared Sub CleanAll() //closes connections, disposes, etc. I have several classes that derive from this base class. The derived classes have all Shared functions that can be called directly from the BLL with no instantiation. The functions in these derived classes call the base Init(), call their specific stored procs, call the base CleanAll() and then return the results. So if I have 5 derived classes with 10 functions each, totaling 50 possible function calls, since they are all Shared, the CLR only calls one at a time, right? All calls are queued to wait until each Shared function completes. Is there a better design with having Shared functions in your DAL and still have base class functions? Or since I have a base class, is it better to move towards instance methods within the DAL?

    Read the article

  • don't wanna lose data on Android after uninstalling

    - by soclose
    Hi, Now I make a trial application. I'd like to store IMEI and other info in Android permanently. And I don't want to lose them after uninstalling it. I tested with shared preference but it deletes after un-installation. SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0); SharedPreferences.Editor editor = settings.edit(); editor.putBoolean("silentMode", true); // Commit the edits! editor.commit(); let me know where to store.

    Read the article

  • Retrieving data from facebook in a winform

    - by gillyb
    Hey, I understand that using the facebook API I need an api key to connect, but I still don't understand how i would go about doing this, and how can i retrieve information upon users using the API (i'm only interested in retrieving the information that is publicly available e.g: username, birthdate, and other info that a specific user left public) I downloaded the facebook development kit, and tried adding the FacebookService control, but i don't get it... All the examples/samples i found on the internet are older than the version i have and therefore work a little different.. Can someone please post an example of how i would connect, using a certain API key, and retrieve someones public info/public photos (if there are any) ?? Thanks. :)

    Read the article

  • json object composition details

    - by Ethan
    in .json text, is the 'value' in a basic single pair object the title of a value type (e.g. [string, number, object]), or a value for a typed object (e.g. 2, or "dog", or Object3)? This is how http://www.json.org/ presents the information: "An object is an unordered set of name/value pairs. An object begins with { (left brace) and ends with } (right brace). Each name is followed by : (colon) and the name/value pairs are separated by , (comma)."

    Read the article

  • JAVA: storing input into array

    - by Jann
    I need to write a program where the program would generate random letter and i would need to store this random character into an array char[] arrayRandom = new char[10]; for (int i = 0; i < 8; i++) { randomNumLet = (generator.nextInt(20) + 1); System.out.print(arrayRandomLetter[randomNumLet] + " "); arrayRandomLetter[randomNumLet] = arrayRandom[i]; } is there anything wrong with my code? because when i run this and printed the array i get boxes for all the values in the array and there are some letter that this line of code cannot print System.out.print(arrayRandomLetter[randomNumLet] + " "); Thanks

    Read the article

  • Does the type in this KVC validation method matter?

    - by dontWatchMyProfile
    For example, in the docs a KVC-style validation method is implemented like this: -(BOOL)validateAge:(id *)ioValue error:(NSError **)outError They used id* as the type for ioValue. Since that's not part of the method signature, I wonder if it would hurt to do something like: -(BOOL)validateAge:(NSNumber *)ioValue error:(NSError **)outError Is this still fine with KVC?

    Read the article

  • Do you use Styrofoam balls to model your systems?

    - by Nick D
    [Objective-C] Do you still use Styrofoam balls to model your systems, where each ball represents a class? Tom Love: We do, actually. We've also done a 3D animation version of it, which we found to be nowhere near as useful as the Styrofoam balls. There's something about a physical, conspicuous structure hanging from the ceiling right in the middle of a development project that's regularly updated to provide not only the structure of the system that you're building, but also the current status of each one of the classes. We've done it on 19 projects the last time I've counted. One of them was 1,856 classes, which is big - actually, probably bigger than it should be. It was a big commercial project, so it needed to be somewhat big. Masterminds of Programming It is the first time I've read or heard about using styrofoam balls to model classes. Is that a commonly used technique? And, how does that sort of modeling help us to design better the system? If you have any photos to share which can show us how the classes are represented it'd be great!

    Read the article

  • Database time data retrieval, time based queries

    - by Raphael Pineda
    I am new to time manipulation or time arithmetic operations and am currently developing a navigation system with Web server based information and currently I have this Database that contains a table peek hours whose columns are id, start_time, end_time , edge_id, day_of_the_week, edge_weight ------------------------------------------------------------------------ | Peek Hours | ------------------------------------------------------------------------ | | | | | | | | id | start_time | end_time | edge_id | day_of_the_week | edge_weight | | | | | | | | ------------------------------------------------------------------------ I am using PHP as a webservice and so based on the current time i want to get all the records that would fit this equation start_time< current_time < end_time

    Read the article

  • MySql Retrive data from same table.

    - by Muhammad Sajid
    Hi, I have a table which contains id, name, parentId of Top level Menus & their children like: -------------------------------------- id | name | parentId -------------------------------------- 1 | Color | 0 -------------------------------------- 2 | Flower | 0 -------------------------------------- 3 | Red | 1 -------------------------------------- 4 | pink | 1 -------------------------------------- 5 | Rose | 2 -------------------------------------- 6 | Lily | 2 -------------------------------------- And I want to fetch these record some thing that the resultant array must be like --------------------------------------------------------------- id | Pname | parentId | child | childId --------------------------------------------------------------- 1 | Color | 1 | Red | 3 --------------------------------------------------------------- 2 | Color | 1 | Pink | 4 --------------------------------------------------------------- 3 | Flower | 2 | Rose | 5 --------------------------------------------------------------- 4 | Flower | 2 | Lily | 6 --------------------------------------------------------------- my query was like: SELECT name AS Pname FROM myTbl WHERE id = (SELECT parentId FROM myTbl WHERE parentId = 1 ) but mysql say #1242 - Subquery returns more than 1 row Could anyone solve it. Thanks..

    Read the article

  • Storing n-grams in database in < n number of tables.

    - by kurige
    If I was writing a piece of software that attempted to predict what word a user was going to type next using the two previous words the user had typed, I would create two tables. Like so: == 1-gram table == Token | NextWord | Frequency ------+----------+----------- "I" | "like" | 15 "I" | "hate" | 20 == 2-gram table == Token | NextWord | Frequency ---------+------------+----------- "I like" | "apples" | 8 "I like" | "tomatoes" | 12 "I hate" | "tomatoes" | 20 "I hate" | "apples" | 2 Following this example implimentation the user types "I" and the software, using the above database, predicts that the next word the user is going to type is "hate". If the user does type "hate" then the software will then predict that the next word the user is going to type is "tomatoes". However, this implimentation would require a table for each additional n-gram that I choose to take into account. If I decided that I wanted to take the 5 or 6 preceding words into account when predicting the next word, then I would need 5-6 tables, and an exponentially increase in space per n-gram. What would be the best way to represent this in only one or two tables, that has no upper-limit on the number of n-grams I can support?

    Read the article

  • How to add additional data column in EF using ASP.Net MVC 2

    - by Picflight
    My Table: [LocationId] [Address] [ZipCode] When I show a list of Location's, I also want to show the distance from a given zip code. In Asp.Net Web Forms I had a stored procedure that would return the distance and I would call this SP on ItemDataBound on my GridView. Or, I also would have my SP that is returning the Location list add another column ([Distance]) which I could display in my GridView. How would you do this using Entity Framework and Asp.Net Mvc 2?

    Read the article

  • Predicate crashing iPhone App!

    - by DVG
    To preface, this is a follow up to an inquiry made a few days ago: http://stackoverflow.com/questions/2981803/iphone-app-crashes-when-merging-managed-object-contexts Short Version: EXC_BAD_ACCESS is crashing my app, and zombie-mode revealed the culprit to be my predicate embedded within the fetch request embedded in my Fetched Results Controller. How does an object within an object get released without an explicit command to do so? Long Version: Application Structure Platforms View Controller - Games View Controller (Predicated upon platform selection) - Add Game View Controller When a row gets clicked on the Platforms view, it sets an instance variable in Games View for that platform, then the Games Fetched Results Controller builds a fetch request in the normal way: - (NSFetchedResultsController *)fetchedResultsController{ if (fetchedResultsController != nil) { return fetchedResultsController; } //build the fetch request for Games NSFetchRequest *request = [[NSFetchRequest alloc] init]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"Game" inManagedObjectContext:context]; [request setEntity:entity]; //predicate NSPredicate *predicate = [NSPredicate predicateWithFormat:@"platform == %@", selectedPlatform]; [request setPredicate:predicate]; //sort based on name NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil]; [request setSortDescriptors:sortDescriptors]; //fetch and build fetched results controller NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:request managedObjectContext:context sectionNameKeyPath:nil cacheName:@"Root"]; aFetchedResultsController.delegate = self; self.fetchedResultsController = aFetchedResultsController; [sortDescriptor release]; [sortDescriptors release]; [predicate release]; [request release]; [aFetchedResultsController release]; return fetchedResultsController; } At the end of this method, the fetchedResultsController's _fetch_request - _predicate member is set to an NSComparisonPredicate object. All is well in the world. By the time - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section gets called, the _predicate is now a Zombie, which will eventually crash the application when the table attempts to update itself. I'm more or less flummoxed. I'm not releasing the fetched results controller or any of it's parts, and the only part getting dealloc'd is the predicate. Any ideas?

    Read the article

  • How can I create multiple identical AWS EC2 server instances with large amounts of persistent data?

    - by mojones
    I have a CPU-intensive data-processing application that I want to run across many (~100,000) input files. The application needs a large (~20GB) data file in order to run. What I would like to do is create an EC2 machine image that has my application and associated data files installed boot up a large number (e.g. 100) of instances of this image split my input files up into 100 batches and send one batch to be processed on each instance I am having trouble figuring out the best way to ensure that each instance has access to the large data file. The data file is too big to fit on the root filesystem of an AMI. I could use Block Storage, but a given Block Storage volume can only be attached to a single instance, so I would need 100 clones. Is there some way to create a custom image that has more space on the root filsystem so that I can include my large data file? Or is there a better way to tackle this problem?

    Read the article

  • Can I use a keyPath in a predicate?

    - by dontWatchMyProfile
    For some reason, this didn't work (although the keypath does exist): NSPredicate *predicate = [NSPredicate predicateWithFormat:@"department.departmentName == %@", departmentName]; [fetchRequest setPredicate:predicate]; NSError *fetchError = nil; NSUInteger count = [moc countForFetchRequest:fetchRequest error:&fetchError]; // execution simply stops at this line, with no error or console log Execution just stops at the last line above when asking for the count. I don't get an console log. Also I don't get any kind of exception. The execution just stops. There are no objects in the persistent store yet. So maybe it crashes because of it tries to follow a keypath in a nonexisting object? Does that make sense? The line where GDB stops is this: 0x002a31cb <+0459> test %eax,%eax Previously to that, I see a lot of NSSQLAdapter... calls in the stack trace. There's definitely something wrong. Well, but when I set the Entity to the destination of the key path and then just do something like NSPredicate *predicate = [NSPredicate predicateWithFormat:@"departmentName == %@", departmentName]; then there is no problem and count simply is 0.

    Read the article

  • WPF how to fill combobox in data grid

    - by Rizwan Ullah
    public class DA_ActivityType { public int Id { get; set; } public string Name { get; set; } } public static List GetActivitytypes() { DataContext dbo = new DataContext(); IEnumerable activityTypes = from actType in dbo.ActivityTypes select new DA_ActivityType { Id = actType.TypeId, Name = actType.Name }; return activityTypes.ToList(); } //XAML Code

    Read the article

  • WPF - data binding trigger before content changed

    - by 0xDEAD BEEF
    How do i create trigger, which fires BEFORE binding changes value? How to do this for datatemplate? <ContentControl Content="{Binding Path=ActiveView}" Margin="0,95,0,0"> <ContentControl.Triggers> <--some triger to fire, when ActiveView is changing or has changed ?!?!? --> </ContentControl.Triggers> public Object ActiveView { get { return m_ActiveView; } set { if (PropertyChanging != null) PropertyChanging(this, new PropertyChangingEventArgs("ActiveView")); m_ActiveView = value; if (PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs("ActiveView")); } } How to do this for DataTemplate? <DataTemplate DataType="{x:Type us:LOLClass1}"> <ContentControl> <ContentControl.RenderTransform> <ScaleTransform x:Name="shrinker" CenterX="0.0" CenterY="0.0" ScaleX="1.0" ScaleY="1.0"/> </ContentControl.RenderTransform> <us:UserControl1/> </ContentControl> <DataTemplate.Triggers> <-- SOME TRIGER BEFORE CONTENT CHANGES--> <BeginStoryboard> <Storyboard> <DoubleAnimation Storyboard.TargetName="shrinker" Storyboard.TargetProperty="ScaleX" From="1.0" To="0.8" Duration="0:0:0.3"/> <DoubleAnimation Storyboard.TargetName="shrinker" Storyboard.TargetProperty="ScaleY" From="1.0" To="0.8" Duration="0:0:0.3"/> </Storyboard> </BeginStoryboard> </-- SOME TRIGER BEFORE CONTENT CHANGES--> </DataTemplate.Triggers> </DataTemplate> How to get notification BEFORE binding is changed? (i want to capture changing Visual component to bitmap and create sliding view animation)

    Read the article

  • where should i encode this html data in an asp.net mvc site

    - by ooo
    here is my view code: <%=Model.HtmlData %> here is my controller code: public ActionResult GetPage() { ContentPageViewModel vm = new ContentPageViewModel(); vm.HtmlData = _htmlPageRepository.Get("key"); return View(vm); } my repository class basically queries a database table that has the fields: id, pageName, htmlContent the .Get() method passes in a pageName (or key) and returns the htmlContent value. Right now i have just started this (haven't persisted anything to the db yet) so i am not doing any explicit encoding in my code now. What is the best practice for where i need to do encoding (in the model, the controller, the view ??)

    Read the article

  • Silverlight Data Binding for Collection in Stack Panel

    - by Blake Blackwell
    I'm new to Silverlight, so I don't have a complete grasp of all the controls at my disposal. What I would like to do is use databinding and a view model to maintain a collection of items. Here is some mock code for what I'd like to do: Model public class MyItem { public string DisplayText { get; set; } public bool Enabled { get; set; } } ViewModel public class MyViewModel : INotifyPropertyChanged { private ObservableCollection<MyItem> _myItems = new ObservableCollection<MyItem>(); public ObservableCollection<MyItem> MyItems { get { return _myItems; } set { _myItems = value NotifyPropertyChanged(this, "MyItems"); } } } View <Grid x:Name="LayoutRoot" Background="White"> <StackPanel ItemsSource="{Binding MyItems}"> <StackPanel Orientation="Horizontal"> <CheckBox "{Binding Enabled, Mode=TwoWay}"></CheckBox> <TextBlock Text="{Binding DisplayText, Mode=TwoWay}" /> </StackPanel> </StackPanel> </Grid> So my end goal would be that every time I add another MyItem to the MyItems collection it would create a new StackPanel with checkbox and textblock. I don't have to use a stack panel but just thought I'd use that for this sample.

    Read the article

  • How do you make an in-place construction of a struct casted to array compile in Visual C++ 2008?

    - by Irwin1138
    I'm working with quite a big codebase which compiles fine in linux but vc++ 2008 spits errors. The problem code goes like this: Declaration: typedef float vec_t; typedef vec_t vec2_t[2]; The codebase is littered with in-place construction like this one: (vec2_t){0, divs} Or more complex: (vec2_t){ 1/(float)Vid_GetScreenW(), 1/(float)Vid_GetScreenH()} As far as I know, this code constructs a struct, then converts it to an array and passes the address to the function. I personally never used in-place construction like this so I have no clue how to make this one work. I don't maintain the linux build, only the windows one. And I can't get it to compile. Is there some switch, some macro to make vc++ compile it? Maybe there is a similar nifty way to construct those arrays and pass them to the functions in-place that compiles just fine in vc++?

    Read the article

  • Better way to summarize data about stop times?

    - by Vimvq1987
    This question is close to this: http://stackoverflow.com/questions/2947963/find-the-period-of-over-speed Here's my table: Longtitude Latitude Velocity Time 102 401 40 2010-06-01 10:22:34.000 103 403 50 2010-06-01 10:40:00.000 104 405 0 2010-06-01 11:00:03.000 104 405 0 2010-06-01 11:10:05.000 105 406 35 2010-06-01 11:15:30.000 106 403 60 2010-06-01 11:20:00.000 108 404 70 2010-06-01 11:30:05.000 109 405 0 2010-06-01 11:35:00.000 109 405 0 2010-06-01 11:40:00.000 105 407 40 2010-06-01 11:50:00.000 104 406 30 2010-06-01 12:00:00.000 101 409 50 2010-06-01 12:05:30.000 104 405 0 2010-06-01 11:05:30.000 I want to summarize times when vehicle had stopped (velocity = 0), include: it had stopped since "when" to "when" in how much minutes, how many times it stopped and how much time it stopped. I wrote this query to do it: select longtitude, latitude, MIN(time), MAX(time), DATEDIFF(minute, MIN(Time), MAX(time)) as Timespan from table_1 where velocity = 0 group by longtitude,latitude select DATEDIFF(minute, MIN(Time), MAX(time)) as minute into #temp3 from table_1 where velocity = 0 group by longtitude,latitude select COUNT(*) as [number]from #temp select SUM(minute) as [totaltime] from #temp3 drop table #temp This query return: longtitude latitude (No column name) (No column name) Timespan 104 405 2010-06-01 11:00:03.000 2010-06-01 11:10:05.000 10 109 405 2010-06-01 11:35:00.000 2010-06-01 11:40:00.000 5 number 2 totaltime 15 You can see, it works fine, but I really don't like the #temp table. Is there anyway to query this without use a temp table? Thank you.

    Read the article

< Previous Page | 375 376 377 378 379 380 381 382 383 384 385 386  | Next Page >