Search Results

Search found 44734 results on 1790 pages for 'model based design'.

Page 398/1790 | < Previous Page | 394 395 396 397 398 399 400 401 402 403 404 405  | Next Page >

  • .Net - Whats the difference between a Session Facade and Business Delegate?

    - by KP65
    What I understand so far: Business Delegate - In the presentation tier, as an ASP component, provides an interface for ASP views to access business components without exposing their API, therefore reducing coupling between the two. Session Facade - In the business tier, as a com+ component, encapsulates business objects, provides a course grain interface for views to access business components. Reduces coupling, hides complex business component interaction from views. So what is the actual difference? They seem pretty similar to me..

    Read the article

  • Need a good way to store data in a DB from a table on a webpage that can have N columns.

    - by Abe Miessler
    Users need to be able to add a specific type of column to an otherwise static table on my web page and then save the information they enter in there to the database. I've been told that in reality they will almost never go over 5 columns but I would rather support N. The columns will all be of the same datatype. My first thought was to have an XML column with the values from all added columns in there but I was curious if anyone else had come up with a better solution. Suggestions?

    Read the article

  • Need some clarification on the ANSI/SPARC 3-tier database architecture.

    - by Moonshield
    Hi there, I'm currently revising for a databases exam and looking over some past papers, but there's one question that I'm slightly unsure about and was wondering if someone could offer some assistance. "Describe EACH of the THREE levels of the ANSI SPARC 3 level architecture. Your answer should include the purpose of EACH of the schemas, the level of abstraction they provide and the software tools that would be used to access and support them." As I understand it (although please correct me if I'm wrong): the internal schema specifies the physical storage of the data; the conceptual schema specifies the structure of the database and the domains; and the external schemas are how the database is viewed by "users" (applications, etc.). As for the abstraction, I understand that the conceptual layer means that the physical data storage can be altered without the end user being affected, likewise the The bit that I'm not sure about is what tools are used to access and support each layer. Would the internal schema be handled by the DBMS, the conceptual schema handled by some sort of DDL interpreter and the external schema handled by a DML interpreter (or have I misunderstood what each level does)? Any assistance would be greatly appreciated. Thanks, Moonshield

    Read the article

  • Error: Too Many Arguments Specified when Inserting Values from ASP.NET to SQL Server

    - by SidC
    Good Afternoon All, I have a wizard control that contains 20 textboxes for part numbers and another 20 for quantities. I want the part numbers and quantities loaded into the following table: USE [Diel_inventory] GO /****** Object: Table [dbo].[QUOTEDETAILPARTS] Script Date: 05/09/2010 16:26:54 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[QUOTEDETAILPARTS]( [QuoteDetailPartID] [int] IDENTITY(1,1) NOT NULL, [QuoteDetailID] [int] NOT NULL, [PartNumber] [float] NULL, [Quantity] [int] NULL, CONSTRAINT [pkQuoteDetailPartID] PRIMARY KEY CLUSTERED ( [QuoteDetailPartID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO ALTER TABLE [dbo].[QUOTEDETAILPARTS] WITH CHECK ADD CONSTRAINT [fkQuoteDetailID] FOREIGN KEY([QuoteDetailID]) REFERENCES [dbo].[QUOTEDETAIL] ([ID]) ON UPDATE CASCADE ON DELETE CASCADE GO Here's the snippet from my sproc for this insert: set @ID=scope_identity() Insert into dbo.QuoteDetailParts (QuoteDetailPartID, QuoteDetailID, PartNumber, Quantity) values (@ID, @QuoteDetailPartID, @PartNumber, @Quantity) When I run the ASPX page, I receive an error that there are too many arguments specified for my stored procedure. I understand why I'm getting the error, given the above table layout. However, I need help in structuring my insert syntax to look for values in all 20 PartNumber and Quantity field pairs. Thanks, Sid

    Read the article

  • Explain "Leader/Follower" Pattern

    - by Alex B
    I can't seem to find a good explanation of "Leader/Follower" pattern. All explanations either simply refer to it in the context of some problem, or are completely meaningless. Can anyone explain to the the mechanics of how this pattern works, and why and how it improves performance over more traditional asynchronous IO models? Examples and links to diagrams are appreciated too.

    Read the article

  • DI with disposable objects

    - by sunnychaganty
    Suppose my repository class looks like this: class myRepository : IDisposable{ private DataContext _context; public myRepository(DataContext context){ _context = context; } public void Dispose(){ // to do: implement dispose of DataContext } } now, I am using Unity to control the lifetime of my repository & the data context & configured the lifetimes as: DataContext - singleton myRepository - create a new instance each time Does this mean that I should not be implementing the IDisposable on the repository to clean up the DataContext? Any guidance on such items?

    Read the article

  • How can I position QDockWidgets as the screen shot shows using code?

    - by Nathan
    I want a Qt window to come up with the following arrangement of dock widgets on the right. Qt allows you to provide an argument to the addDockWidget method of QMainWindow to specify the position (top, bottom, left or right) but apparently not how two QDockWidgets placed on the same side will be arranged. Here is the code that adds the dock widgets. this uses PyQt4 but it should be the same for Qt with C++ self.memUseGraph = mem_use_widget(self) self.memUseDock = QDockWidget("Memory Usage") self.memUseDock.setObjectName("Memory Usage") self.memUseDock.setWidget(self.memUseGraph) self.addDockWidget(Qt.DockWidgetArea(Qt.RightDockWidgetArea),self.memUseDock) self.diskUsageGraph = disk_usage_widget(self) self.diskUsageDock = QDockWidget("Disk Usage") self.diskUsageDock.setObjectName("Disk Usage") self.diskUsageDock.setWidget(self.diskUsageGraph) self.addDockWidget(Qt.DockWidgetArea(Qt.RightDockWidgetArea),self.diskUsageDock) When this code is used to add both of them to the right side, one is above the other, not like the screen shot I made. The way I made that shot was to drag them there with the mouse after starting the program, but I need it to start that way.

    Read the article

  • C++ inheritance and member function pointers

    - by smh
    In C++, can member function pointers be used to point to derived (or even base) class members? EDIT: Perhaps an example will help. Suppose we have a hierarchy of three classes X, Y, Z in order of inheritance. Y therefore has a base class X and a derived class Z. Now we can define a member function pointer p for class Y. This is written as: void (Y::*p)(); (For simplicity, I'll assume we're only interested in functions with the signature void f() ) This pointer p can now be used to point to member functions of class Y. This question (two questions, really) is then: Can p be used to point to a function in the derived class Z? Can p be used to point to a function in the base class X?

    Read the article

  • Managing libraries and imports in a programming language

    - by sub
    I've created an interpreter for a stupid programming language in C++ and the whole core structure is finished (Tokenizer, Parser, Interpreter including Symbol tables, core functions, etc.). Now I have a problem with creating and managing the function libraries for this interpreter (I'll explain what I mean with that later) So currently my core function handler is horrible: // Simplified version myLangResult SystemFunction( name, argc, argv ) { if ( name == "print" ) { if( argc < 1 ) { Error('blah'); } cout << argv[ 0 ]; } else if ( name == "input" ) { if( argc < 1 ) { Error('blah'); } string res; getline( cin, res ); SetVariable( argv[ 0 ], res ); } else if ( name == "exit ) { exit( 0 ); } And now think of each else if being 10 times more complicated and there being 25 more system functions. Unmaintainable, feels horrible, is horrible. So I thought: How to create some sort of libraries that contain all the functions and if they are imported initialize themselves and add their functions to the symbol table of the running interpreter. However this is the point where I don't really know how to go on. What I wanted to achieve is that there is e.g.: an (extern?) string library for my language, e.g.: string, and it is imported from within a program in that language, example: import string myString = "abcde" print string.at( myString, 2 ) # output: c My problems: How to separate the function libs from the core interpreter and load them? How to get all their functions into a list and add it to the symbol table when needed? What I was thinking to do: At the start of the interpreter, as all libraries are compiled with it, every single function calls something like RegisterFunction( string namespace, myLangResult (*functionPtr) ); which adds itself to a list. When import X is then called from within the language, the list built with RegisterFunction is then added to the symbol table. Disadvantages that spring to mind: All libraries are directly in the interpreter core, size grows and it will definitely slow it down.

    Read the article

  • Implementing the procducer-consumer pattern with .NET 4.0

    - by bitbonk
    With alle the new paralell programming features in .NET 4.0, what would be a a simple and fast way to implement the producer-consumer pattern (where at least one thread is producing/enqueuing task items and another thread executes/dequeues these tasks). Can we benfit from all these new APIs? What is your preferred implementation of this pattern?

    Read the article

  • stop the CSS filter property cascading

    - by Ayoub
    I tried to make box-shadow affect work cross browsers, in order to make ie work I used "filter" property but the effect cascades to the child element (in my case a span) I tried to stop it by using filter : none but it didn't work searched the web but I couldn't find a solution. please help me solve this problem. HTML code : <div id="shadow"> <span>text text</span> </div> CSS code : #shadow{ -moz-box-shadow: 3px 3px 4px #000; -webkit-box-shadow: 3px 3px 4px #000; box-shadow: 3px 3px 4px #000; /* For IE 8 */ -ms-filter: "progid:DXImageTransform.Microsoft.Shadow(Strength=4, Direction=135, Color='#000000')"; /* For IE 5.5 - 7 */ filter: progid:DXImageTransform.Microsoft.Shadow(Strength=4, Direction=135, Color='#000000'); }

    Read the article

  • Usability: Save changes using "Apply" button or after every single change?

    - by mr.b
    I am interested in hearing opinions and experiences of fellow developers on topic of designing user interface, usability AND maintainability-wise. Common approach is to allow users to tweak options and after form gets "dirty", enable "Apply" button, and user has possibility to back out by pressing cancel. This is most common approach on Windows platform (I believe MS usability guidelines say to do so as well). Another way is to apply changes after every single change has been made to options. Example, user checks some checkbox, and change is applied. User changes value of some text box, and change is applied after box looses focus, etc. You get the point. This approach is most common on Mac OSX. Regardless of my personal opinion (which is that Apple is better at usability, but software I usually write targets Windows users), what do you people think?

    Read the article

  • How to bring the parent element with floated child elements to the center of the document?

    - by Starx
    I have organized a menu. Its HTML is as follows: <ul class="topmenu"> <li><a href="sample.html">Text 1</a></li> <li><a href="sample.html">Text 2</a></li> <li><a href="sample.html">Text 3</a></li> <li><a href="sample.html">Text 4</a></li> <ul> This is a horizontal menu, so I have floated the list items to left to appear them in a horizontal line. I could have used display:inline to appear them in a single line, but since IE does not support it and I don't know any other way to do so, I used float:left;. It's css is: .topmenu { list-style:none; margin:0; padding:0; } .topmenu li { float:left; } This brings the menu in a perfect horizontal line, but the entire list is floated to the left. I want to bring the .topmenu to appear in the center of the document and keep the listitem inside it floated towards the left. I found that this is achievable by defining width property of the .topmenu, but I dont want to fix its width as the list-items are dynamically generated and thus could increase and decrease. Any one know of any solution?

    Read the article

  • domain modeling naming problem

    - by cherouvim
    Hello There are some simple entities in an application (e.g containing only id and title) which rarely change and are being referenced by the more complex entities of the application. These are usually entities such as Country, City, Language etc. How are these called? I've used the following names for those in the past but I'm not sure which is the best way to call them: reference data lookup values dictionaries thanks

    Read the article

  • Is the a pattern for iterating over lists held by a class (dynamicly typed OO languages)

    - by Roman A. Taycher
    If I have a class that holds one or several lists is it better to allow other classes to fetch those lists(with a getter) or to implement a doXList/eachXList type method for that list that take a function and call that function on each element of the list contained by that object. I wrote a program that did a ton of this and I hated passing around all these lists sometimes with method in class a calling method in class B to return lists contained in class C, B contains a C or multiple C's (note question is about dynamically typed OO languages languages like ruby or smalltalk) ex. (that came up in my program) on a Person class containing scheduling preferences and a scheduler class needing to access them.

    Read the article

  • How do I calculate a good hash code for a list of strings?

    - by Ian Ringrose
    Background: I have a short list of strings. The number of strings is not always the same, but are nearly always of the order of a “handful” In our database will store these strings in a 2nd normalised table These strings are never changed once they are written to the database. We wish to be able to match on these strings quickly in a query without the performance hit of doing lots of joins. So I am thinking of storing a hash code of all these strings in the main table and including it in our index, so the joins are only processed by the database when the hash code matches. So how do I get a good hashcode? I could: Xor the hash codes of all the string together Xor with multiply the result after each string (say by 31) Cat all the string together then get the hashcode Some other way So what do people think? (If you care we are using .NET and SqlServer)

    Read the article

  • One page of responsive site is blurry/fuzzy on iphone

    - by Gwendydd
    Here's a weird one. I'm developing a responsive site here: http://74.209.178.54:3000/index.html There are three pages built so far: the home page, the "Why" page, and the "Pricing" page. The Home and Why pages are just fine on my iPhone 4. The "Pricing" page is really blurry. And I don't just mean the images are blurry - absolutely everything is blurry: text, borders, backgrounds... Has anyone seen this before? Do you know what's happening?

    Read the article

  • how to tackle a custom forms database

    - by Neil Hickman
    I'm currently researching a project for the place that I work in. We are trying to create a system that will allow forms to be set up dynamically from a database. My question is what database structure would best suit something like this? I currently have a structure of: forms_form forms_formfields forms_formdata I don't think this is the most appropriate layout for this. Basically to make is make sense I need to be able to make a form within the database that can have infinite fields all customized and have the data when submitted stored in the database.

    Read the article

  • many-to-many-to-many, incl alignment of data from diff sources

    - by JefeCoon
    Re-factoring dbase to support many:many:many. At the second and third levels we need to preserve end-user 'mapping' or aligning of data from different sources, e.g. Order 17 FirstpartyOrderID => aha LineItem_for_BigShinyThingy => AA-1 # maps to 77-a LineItem_for_BigShinyThingy => AA-2 # maps to 77-b, 77-c LineItem_for_LittleWidget => AA-x # maps to 77-zulu, 77-alpha, 99-foxtrot LineItem_for_LittleWidget => AA-y # maps to 77-zulu, 99-foxtrot LineItem_for_LittleWidget => AA-z # maps to 77-alpha ThirdpartyOrderID => foo LineItem_for_BigShinyThingy => 77-a LineItem_for_BigShinyThingy => 77-b LineItem_for_BigShinyThingy => 77-c LineItem_for_LittleWidget => 77-zulu LineItem_for_LittleWidget => 77-alpha ThirdpartyOrderID => bar LineItem_for_LittleWidget => 99-foxtrot Each LineItem has daily datapoints reported from its own source (Firstparty|Thirdparty). In our UI & app we provide tools to align these, then we'd like to save them into the cleanest possible schema for querying, enabling us to diff the reported daily datapoints, and perform other daily calculations (which we'll store in the dbase also, fortunately that should be cake once we've nailed this). We need to map related [firstparty|thirdparty]line_items which have their own respective datapoints. We'll be using the association to pull each line_items collection of datapoints for summary and discrepancy calculations. I'm considering two options, std has_many,through x2 --or-- possibly (scary) ubermasterjoin table OptionA: order<<-->> order_join_table[id,order_id,firstparty_order_id,thirdparty_order_id] <<-->>line_item order_join_table[firstparty_order_id]-->raw_order[id] order_join_table[thirdparty_order_id]-->raw_order[id] raw_order-->raw_line_items[raw_order_id] line_item<<-->> line_item_join[id,LI_join_id,firstparty_LI,thirdparty_LI <<-->>raw_line_items line_item_join[firstparty_LI]-->raw_line_item[id] line_item_join[thirdparty_LI]-->raw_line_item[id] raw_line_item<<-->>datapoints = we rely upon join to store all mappings of first|third orders & line_items = keys to raw_* enable lookup of these order & line_item details = concerns about circular references and/or lack of correct mapping logic, e.g order--line_item--raw_line_items vs. order--raw_order--raw_line_items OptionB: order<<-->> join_master[id,order_id,FP_order_id,TP_order_id,FP_line_item_id,TP_line_item_id] join_master[FP_order_id & TP_order_id]-->raw_order[id] join_master[FP_line_item_id & TP_line_item_id]-->raw_line_item[id] = every combo of FP_line_item + TP_line_item writes a record into the join_master table = "theoretically" queries easy/fast/flexible/sexy At long last, my questions: a) any learnings from painful firsthand experience about how best to implement/tune/optimize many-to-many-to-many relationships b) in rails? c) any painful gotchas (circular references, slow queries, spaghetti-monsters) to watch out for? d) any joy & goodness in Rails3 that makes this magically easy & joyful? e) anyone written the "how to do many-to-many-to-many schema in Rails and make it fast & sexy?" tutorial that I somehow haven't found? If not, I'll follow up with our learnings in the hope it's helpful.. Thanks in advance- --Jeff

    Read the article

  • C# Linq: Can you merge DataContexts?

    - by Andreas Grech
    Say I have one database, and this database has a set of tables that are general to all Clients and some tables that are specific to certain clients. Now what I have in mind is creating a primary DataContext that includes only the tables that are general to all the clients, and then create separate DataContexts that contain only the tables that are specific to the client. Is there a way to kind of "merge" DataContexts so that it becomes one context? So for Client A, I need one DataContext that includes both the general tables and also the tables for that specific client (retrieved from two different DataContexts) ? [Update] What I think I can do is, from the Partial Class of the DataContext instead of letting my DataContext inherit from DataContext I make it inherit from MyDataContext; that way, the tables from MyDataContext and the other DataContext will be available in one DataContext class. What do you think about this approach? Of course with something like this you can only merge two datacontexts at once though...

    Read the article

< Previous Page | 394 395 396 397 398 399 400 401 402 403 404 405  | Next Page >