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  • Can't install Dual Boot from USB live - crash and nouvea problem

    - by user215064
    I just got a new laptop with Windows 8 pre-installed and I'm trying to make a dual boot with Ubuntu on my other hard drive but I can't make the Live USB work. I followed all the procedure for disabling the Security Boot and the UEFI setting but still doesn't work. It seems to start the installing procedure but I never get to choose anything: after a few seconds the screen turns black with an error message [18.707838] divide error: 0000 [#1] SMP (it goes on for several lines quoting some nouveau problem). Any ideas?

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  • boot problem in samsung

    - by user286366
    i have formatted my laptop completely and installed Ubuntu 14.4 after installation Ubuntu is not booting directly i have to put the pen drive(which has Ubuntu 14.4 live cd) every time on start up and press f4 which is for recovery after booting if take the pen drive then no problem its working normally my laptop is Samsung np370 with Intel i5 3rd gen processor with 6gb ram and 1tb hard disk please help me

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  • login problem for 13.10, my username does not appear

    - by Anand
    After upgrading my Ubuntu to the newest version 13.10, in the login interface, my account does not appear. I can login the guest session. There is also a remote login. I have no place to input my username to login my account. Does anyone have the same problem? ----EDIT---- Here is the file lightdm.conf [SeatDefaults] greeter-session=unity-greeter user-session=ubuntu ----EDIT TWO--- Here is the official bug report: https://bugs.launchpad.net/ubuntu/+source/unity-greeter/+bug/1235785

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  • Problem with Software Center

    - by user215391
    I am not able use my Ubuntu Software Center and Synaptic package manager. I can't understand what's the problem. When I use the command: sudo apt-get update it shows this error: E: Malformed line 1 in source list /etc/apt/sources.list.d/canonical_partner.list (dist parse) E: The list of sources could not be read. I have seen How do I remove a malformed line from my sources.list?, but it didn't help.

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  • problem after suspend ubuntu 12.04

    - by alex
    I'd like to have a thing cleared. I just started using Ubuntu and installed 12.04 the only problem is that when i turn my laptop back on after suspension i get a black screen with this written: legacy_resume():pnp_bus_resume+0x0/0x70 return -19 PM: Device 00:09 failed to resume: error -19 i8042: Can't reactivate AUX port and after this message at times my touchpad doesn't work as well. I am currently using a vpc eh2n1e thanks for the support

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  • Problem connecting to certain wifi networks

    - by Romas
    I'm using lenovo u300s (it has Intel Centrino Wireless-N 1030 card), and I can connect to wireless network at home with no problem, but I can not connect to any networks at my university. I'm not sure if it's the case but most of university networks are open and you need to sign up your username as you enter browser. There is also an eudoroam network, but I can not connect to it either. Any suggestions? Yes I have the latest ubuntu version.

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  • AMD Drivers problem

    - by Darthkpo
    So, I'm kind of new to Ubuntu and Linux in general, I installed the latest (Ubuntu 14.04) and everything went fine, except for the resolution so I thought that it was a driver problem because I have a AMD HD 7750 and maybe it required additional proprietary drivers so I installed AMD Catalyst (Latest version), and then rebooted. And now my monitor says Can't Display and I can't see the GUI. I can go to terminal (Pressing Ctrl + Alt + F1, F2, F3 etc) but Not the UI.

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  • Collision detection problem in XNA

    - by Fantasy
    I'm having two problems with my collision detection in XNA. There are two boxes, the red box represents a player and the blue box represents a wall. The first problem is when the player moves to the upper side or bottom side of the wall and collides with it, and then try to go to the left or right, the player will just jump in the opposite direction as seen in the video. However if I go to the right side or the left side of the wall and try to go up or down the player will smoothly go up or down without jumping. The second problem is that when I collide with the box and my key is still pressed down the blue box goes half way through red box and and goes back out and it keeps doing that until I stop pressing the keyboard. its not very clear on the video but the keeps going in and out really fast until I stop pressing the key. Here is a video example:- http://www.youtube.com/watch?v=mKLJsrPviYo and Here is my code Vector2 Position; Rectangle PlayerRectangle, BoxRectangle; float Speed = 0.25f; enum Direction { Up, Right, Down, Left }; Direction direction; protected override void Update(GameTime gameTime) { // Allows the game to exit if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed) this.Exit(); KeyboardState keyboardState = Keyboard.GetState(); if (keyboardState.IsKeyDown(Keys.Up)) { Position.Y -= (float)(Speed * gameTime.ElapsedGameTime.TotalMilliseconds); direction = Direction.Up; } if (keyboardState.IsKeyDown(Keys.Down)) { Position.Y += (float)(Speed * gameTime.ElapsedGameTime.TotalMilliseconds); direction = Direction.Down; } if (keyboardState.IsKeyDown(Keys.Right)) { Position.X += (float)(Speed * gameTime.ElapsedGameTime.TotalMilliseconds); direction = Direction.Right; } if (keyboardState.IsKeyDown(Keys.Left)) { Position.X -= (float)(Speed * gameTime.ElapsedGameTime.TotalMilliseconds); direction = Direction.Left; } if (PlayerRectangle.Intersects(BoxRectangle)) { if (direction == Direction.Right) Position.X = BoxRectangle.Left - PlayerRectangle.Width; else if (direction == Direction.Left) Position.X = BoxRectangle.Right; if (direction == Direction.Down) Position.Y = BoxRectangle.Top - PlayerRectangle.Height; else if (direction == Direction.Up) Position.Y = BoxRectangle.Bottom; } PlayerRectangle = new Rectangle((int)Position.X, (int)Position.Y, (int)32, (int)32); base.Update(gameTime); }

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  • network problem

    - by TimbooXD
    I was trying to make my IP static from my ubuntu 12.10 laptop but I made a mistake and after restarting with sudo /etc/init.d/networking restart Ubuntu crashed. So after restart my system it said that it couldn't use the network. Now I need to reconnect to the Internet and make my ip static. It is for a server and that isn't the problem, but how can I reconnect and make my ip static and which data I need to know?

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  • Problem in searching String array [on hold]

    - by user2573607
    I'm working on a bank interface project, where I have to search an array of string when the user types in his username. The array has 10 strings, but only the first string is recognized as a valid username...I'm positive that the syntax of the search technique(Linear Search) is correct, but I cannot seem to find the problem. The code however compiles properly. Any answer will be appreciated, TIA! Aparna

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  • SelectMany in Linq to entity

    - by Brazeta
    I was looking at some examples in microsoft site about linq and I see an example that I need to modify! http://msdn.microsoft.com/en-us/vcsharp/aa336758.aspx#SelectManyCompoundfrom3 public void Linq16() { List customers = GetCustomerList(); var orders = from c in customers from o in c.Orders where o.OrderDate >= new DateTime(1998, 1, 1) select new { c.CustomerID, o.OrderID, o.OrderDate }; ObjectDumper.Write(orders); } Insted of having a select that retrives the CustomerID, OrderID and OrderDate I want to select the CustomerID and a System.Collection.Generic.List that contains all the orders for that user! Essentially I want to group my orders by CustomerID, but i noticed that linq to entity does not allow a .ToList(object) inside the select. I want something like this... List customers = GetCustomerList(); var orders = from c in customers from o in c.Orders where o.OrderDate >= new DateTime(1998, 1, 1) select new xpto { TheCostumerID = c.CustomerID, CostumerOrders = o.Select(i=>i.OrderID).ToList(), }; ...but the .ToList() is a big problem, at least for me. I'm trying to find out the solution for that but so far I have acomplished nothing! Please help me.

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  • Uploading to TwitVid using x_verify_credentials_authorization

    - by deepa
    Hi, I am developing an iPhone application that uploads videos to TwitVid using the library TwitVid-iPhone-OAuth3. I have selected this library since Twitter is shifting to OAuth mechanism of authentication. 1) Does this new library allows to upload without user-name and password parameters? 2) I am using the following steps for uploading videos (assumed that new library allows to upload without user-name and password parameters). But, I am getting the error 'Incorrect Signature'. I am not able to identify the mistake that I am doing here. Could you please help me out to solve this problem. Authenticate the app using OAuth (MGTwitterEngine etc) which redirects the user to the web-page asking for log-in and app authentication. If the user authenticates the app, access token will obtained as final step. Upload the video to TwitVid using the following code snippet: OAuth *authorizer = [[OAuth alloc] initWithConsumerKey: @"my_consumer_key" andConsumerSecret: @"my_consumer_secret"]; authorizer.oauth_token = //The key-part of the access token obtained in step 2 authorizer.oauth_token_secret = //The secret-part of the access token obtained in step 2 authorizer.oauth_token_authorized = YES; //Since authenticated in steps 1 and 2 NSString *authHeader = [authorizer oAuthHeaderForMethod: @"POST" andUrl: @"https://api.twitter.com/1/account/verify_credentials.xml" andParams: nil]; twitVid = [[TwitVid alloc] init]; [mTwitVid setDelegate: self]; [mTwitVid authenticateWithXVerifyCredentialsAuthorization: authHeader xAuthServiceProvider: nil]; Thanks and Regards, Deepa

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  • Mono ASP.NET Oracle Connection

    - by bladepit
    Hello to everybody, if i want to connect to orcale i became the following error: libclntsh.so Description: HTTP 500. Error processing request. Stack Trace: System.DllNotFoundException: libclntsh.so at (wrapper managed-to-native) System.Data.OracleClient.Oci.OciCalls/OciNativeCalls.OCIEnvCreate (intptr&,System.Data.OracleClient.Oci.OciEnvironmentMode,intptr,intptr,intptr,intptr,int,intptr) <0x0005d at System.Data.OracleClient.Oci.OciCalls.OCIEnvCreate (intptr&,System.Data.OracleClient.Oci.OciEnvironmentMode,intptr,intptr,intptr,intptr,int,intptr) [0x00000] in /src/monoscript/mono-2.4.2.3/mcs/class/System.Data.OracleClient/System.Data.OracleClient.Oci/OciCalls.cs:738 at System.Data.OracleClient.Oci.OciEnvironmentHandle..ctor (System.Data.OracleClient.Oci.OciEnvironmentMode) [0x00013] in /src/monoscript/mono-2.4.2.3/mcs/class/System.Data.OracleClient/System.Data.OracleClient.Oci/OciEnvironmentHandle.cs:35 at System.Data.OracleClient.Oci.OciGlue.CreateConnection (System.Data.OracleClient.OracleConnectionInfo) [0x00000] in /src/monoscript/mono-2.4.2.3/mcs/class/System.Data.OracleClient/System.Data.OracleClient/OciGlue.cs:86 at System.Data.OracleClient.OracleConnectionPoolManager.CreateConnection (System.Data.OracleClient.OracleConnectionInfo) [0x00006] in /src/monoscript/mono-2.4.2.3/mcs/class/System.Data.OracleClient/System.Data.OracleClient/OracleConnectionPoolManager.cs:57 at System.Data.OracleClient.OracleConnectionPool.CreateConnection () [0x0000e] in /src/monoscript/mono-2.4.2.3/mcs/class/System.Data.OracleClient/System.Data.OracleClient/OracleConnectionPool.cs:97 at System.Data.OracleClient.OracleConnectionPool.GetConnection () [0x000ba] in /src/monoscript/mono-2.4.2.3/mcs/class/System.Data.OracleClient/System.Data.OracleClient/OracleConnectionPool.cs:74 at System.Data.OracleClient.OracleConnection.Open () [0x00061] in /src/monoscript/mono-2.4.2.3/mcs/class/System.Data.OracleClient/System.Data.OracleClient/OracleConnection.cs:410 at WebServer.Controllers.HomeController.Index () [0x00006] in /home/bhcweb/Projects/Controllers/HomeController.cs:19 at (wrapper dynamic-method) System.Runtime.CompilerServices.ExecutionScope.lambda_method (System.Runtime.CompilerServices.ExecutionScope,System.Web.Mvc.ControllerBase,object[]) <0x00080 at System.Web.Mvc.ActionMethodDispatcher.Execute (System.Web.Mvc.ControllerBase,object[]) <0x0001b at System.Web.Mvc.ReflectedActionDescriptor.Execute (System.Web.Mvc.ControllerContext,System.Collections.Generic.IDictionary2<string, object>) <0x000fd> at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod (System.Web.Mvc.ControllerContext,System.Web.Mvc.ActionDescriptor,System.Collections.Generic.IDictionary2) <0x0001c at System.Web.Mvc.ControllerActionInvoker/c_AnonStoreyB.<m_E () <0x00067 at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter (System.Web.Mvc.IActionFilter,System.Web.Mvc.ActionExecutingContext,System.Func`1) <0x000c4 What is my Problem there? I have read that i have to set my ORACLE_HOME AND LD_LIBRARY_PATH. If i do echo $ORACLE_HOME and $LD_LIBRARY_PATH the path which i have set is coming out: /usr/lib/oracle/xe/app/oracle/product/10.2.0/client/lib This is the path where the libclntsh.so is in. Is this right? Best regards bladepit

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  • Getting Google results in Java? Need help!

    - by Cris Carter
    Hello. Right now, I'm trying to get the results from Google in Java, by searching for a term. I'm using a desktop program, not an applet. That in itself isn't complicated. but then Google gave me a 403 error. Anyways, I added referrer and User Agent and then it worked. Now, my problem is that I don't get the results page from Google. Instead, I get their script which gets the results page. My code right now simply uses a GET request on "http://www.google.com/search?q=" + Dork; Then it outputs each line. Here is what I get when I run my program: <.!doctype html<.head<.titledork - Google Search<./title<.scriptwindow.google={kEI:"9myaS-Date).getTime()}}};try{}catch(u){}window.google.jsrt_kill=1; align:center}#logo{display:block;overflow:hidden;position:relative;width:103px;height:37px; <./ script<./div Lots of stuff like that. I shortened it (A LOT) and put in dots to fit it here. So my big question is: How do I turn this whole mess into the nice results page I get when searching Google with a browser? Any help would be seriously appreciated, and I really need the answer fast. Also, please keep in mind that I do NOT want to use Google's API for this. Thanks in advance!

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  • Hibernate HQL m:n join problem

    - by smallufo
    I am very unfamiliar with SQL/HQL , and am currently stuck with this 'maybe' simple problem : I have two many-to-many Entities , with a relation table : Car , CarProblem , and Problem . One Car may have many Problems , One Problem may appear in many Cars, CarProblem is the association table with other properties . Now , I want to find Car(s) with specified Problem , how do I write such HQL ? All ids are Long type . I've tried a lot of join / inner-join combinations , but all in vain.. -- updated : Sorry , forget to mention : Car has many CarProblem Problem has many CarProblem Car and Problem are not directly connected in Java Object. -- update , java code below -- @Entity public class Car extends Model{ @OneToMany(mappedBy="car" , cascade=CascadeType.ALL) public Set<CarProblem> carProblems; } @Entity public class CarProblem extends Model{ @ManyToOne public Car car; @ManyToOne public Problem problem; ... other properties } @Entity public class Problem extends Model { other properties ... // not link to CarProblem , It seems not related to this problem // **This is a very stupid query , I want to get rid of it ...** public List<Car> findCars() { List<CarProblem> list = CarProblem.find("from CarProblem as cp where cp.problem.id = ? ", id).fetch(); Set<Car> result = new HashSet<Car>(); for(CarProblem cp : list) result.add(cp.car); return new ArrayList<Car>(result); } } The Model is from Play! framework , so these properties are all public .

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  • Huge burst of memory in c# service, what could be the cause?

    - by Daniel
    I'm working on a c# service application and i have this problem where out of no where and for no obvious reason, the memory for the process will climb from 150mb to almost 2gb in about 5 seconds and then back to 150mb. But nothing in our system should be using any where near that amount of memory (so its probably a bug somewhere). It might be a tight while true loop somewhere but the cpu usage at the time was very low so i thought i'd look for other ideas. Now the weirder thing is when i compile the service for 64bit, the same massive burst will occur except it exceeded 10gb of ram (paging most of it) and it just caused lots of problems with the computer and everything running on it. After a while it shuts down but it looks like windows is still willing to give it more memory. Would you have any ideas or tools that i can use in order to find this? Yes it has lots of logging however nothing in the logs stand out as to why this is happening. I can run the service in a console app mode, so my next test was going to be running it in visual studio debugger and see if i can find anything. It only happens occasionally but usually about 10-20 minutes after startup. On 32bit mode it cleans up and continues on like normally. 64bit mode it crashes after a while and uses stupid amounts of memory. But i'm really stumped as to why this is happening!!!

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  • Dynamic programming Approach- Knapsack Puzzle

    - by idalsin
    I'm trying to solve the Knapsack problem with the dynamical programming(DP) approach, with Python 3.x. My TA pointed us towards this code for a head start. I've tried to implement it, as below: def take_input(infile): f_open = open(infile, 'r') lines = [] for line in f_open: lines.append(line.strip()) f_open.close() return lines def create_list(jewel_lines): #turns the jewels into a list of lists jewels_list = [] for x in jewel_lines: weight = x.split()[0] value = x.split()[1] jewels_list.append((int(value), int(weight))) jewels_list = sorted(jewels_list, key = lambda x : (-x[0], x[1])) return jewels_list def dynamic_grab(items, max_weight): table = [[0 for weight in range(max_weight+1)] for j in range(len(items)+1)] for j in range(1,len(items)+1): val= items[j-1][0] wt= items[j-1][1] for weight in range(1, max_weight+1): if wt > weight: table[j][weight] = table[j-1][weight] else: table[j][weight] = max(table[j-1][weight],table[j-1][weight-wt] + val) result = [] weight = max_weight for j in range(len(items),0,-1): was_added = table[j][weight] != table[j-1][weight] if was_added: val = items[j-1][0] wt = items[j-1][1] result.append(items[j-1]) weight -= wt return result def totalvalue(comb): #total of a combo of items totwt = totval = 0 for val, wt in comb: totwt += wt totval += val return (totval, -totwt) if totwt <= max_weight else (0,0) #required setup of variables infile = "JT_test1.txt" given_input = take_input(infile) max_weight = int(given_input[0]) given_input.pop(0) jewels_list = create_list(given_input) #test lines print(jewels_list) print(greedy_grab(jewels_list, max_weight)) bagged = dynamic_grab(jewels_list, max_weight) print(totalvalue(bagged)) The sample case is below. It is in the format line[0] = bag_max, line[1:] is in form(weight, value): 575 125 3000 50 100 500 6000 25 30 I'm confused as to the logic of this code in that it returns me a tuple and I'm not sure what the output tuple represents. I've been looking at this for a while and just don't understand what the code is pointing me at. Any help would be appreciated.

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  • binary files writing/reading problems...

    - by ScReYm0
    Ok i have problem with my code for reading binary file... First i will show you my writing code: void book_saving(char *file_name, struct BOOK *current) { FILE *out; BOOK buf; out = fopen(file_name, "wb"); if(out != NULL) { printf_s("Writting to file..."); do { if(current != NULL) { strcpy(buf.catalog_number, current-catalog_number); strcpy(buf.author, current-author); buf.price = current-price; strcpy(buf.publisher, current-publisher); strcpy(buf.title, current-title); buf.price = current-year_published; fwrite(&buf, sizeof(BOOK), 1, out); } current = current-next; }while(current != NULL); printf_s("Done!\n"); fclose(out); } } and here is my "version" for reading: int book_open(struct BOOK *current, char *file_name) { FILE *in; BOOK buf; BOOK *vnext; int count; int i; in = fopen("west", "rb"); printf_s("Reading database from %s...", file_name); if(!in) { printf_s("\nERROR!"); return 1; } i = fread(&buf,sizeof(BOOK), 1, in); while(!feof(in)) { if(current != NULL) { current = malloc(sizeof(BOOK)); current-next = NULL; } strcpy(current-catalog_number, buf.catalog_number); strcpy(current-title, buf.title); strcpy(current-publisher, buf.publisher); current-price = buf.price; current-year_published = buf.year_published; fread(&buf, 1, sizeof(BOOK), in); while(current-next != NULL) current = current-next; fclose(in); } printf_s("Done!"); return 0; } I just need to save my linked list in binary file and to be able to read it back ... please help me. The program just don't read it or its crash every time different situation ...

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  • Best way of storing an "array of records" at design-time

    - by smartins
    I have a set of data that I need to store at design-time to construct the contents of a group of components at run-time. Something like this: type TVulnerabilityData = record Vulnerability: TVulnerability; Name: string; Description: string; ErrorMessage: string; end; What's the best way of storing this data at design-time for later retrieval at run-time? I'll have about 20 records for which I know all the contents of each "record" but I'm stuck on what's the best way of storing the data. The only semi-elegant idea I've come up with is "construct" each record on the unit's initialization like this: var VulnerabilityData: array[Low(TVulnerability)..High(TVulnerability)] of TVulnerabilityData; .... initialization VulnerabilityData[0].Vulnerability := vVulnerability1; VulnerabilityData[0].Name := 'Name of Vulnerability1'; VulnerabilityData[0].Description := 'Description of Vulnerability1'; VulnerabilityData[0].ErrorMessage := 'Error Message of Vulnerability1'; VulnerabilityData[1]...... ..... VulnerabilityData[20]...... Is there a better and/or more elegant solution than this? Thanks for reading.

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  • Using Essential Use Cases to design a UI-centric Application

    - by Bruno Brant
    Hello all, I'm begging a new project (oh, how I love the fresh taste of a new project!) and we are just starting to design it. In short: The application is a UI that will enable users to model an execution flow (a Visio like drag & drop interface). So our greatest concern is usability and features that will help the users model fast and clearly the execution flow. Our established methodology makes extensive use of Use Cases in order to create a harmonious view of the application between the programmers and users. This is a business concern, really: I'd prefer to use an Agile Method with User Stories rather than User Cases, but we need to define a clear scope to sell the product to our clients. However, Use Cases have a number of flaws, most of which are related to the fact that they include technical details, like UI, etc, as can be seem here. But, since we can't use User Stories and a fully interactive design, I've decided that we compromise: I will be using Essential Use Cases in order to hide those details. Now I have another problem: it's essential (no pun intended) to have a clear description of UI interaction, so, how should I document it? In other words, how do I specify a application through the use of Essential Use Cases where the UI interaction is vital to it? I can see some alternatives: Abandon the use of Use Cases since they don't correctly represent the problem Do not include interface descriptions in the use case, but create another documentation (Story Boards) and link then to the Essential Use Cases Include UI interaction description to the Essential Use Cases, since they are part of the business rules in the perspective of the users and the application itself

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  • Starting out Silverlight 4 design

    - by Fermin
    I come from mainly a web development background (ASP.NET, ASP.NET MVC, XHTML, CSS etc) but have been tasked with creating/designing a Silverlight application. The application is utilising Bing Maps control for Silverlight, this will be contained in a user control and will be the 'main' screen in the system. There will be numerous other user controls on the form that will be used to choose/filter/sort/order the data on the map. I think of it like Visual Studio: the Bing Maps will be like the code editor window and the other controls will be like Solutions Explorer, Find Results etc. (although a lot less of them!) I have read up and I'm comfortable with the data side (RIA-Services) of the application. I've (kinda) got my head around databinding and using a view model to present data and keep the code behind file lite. What I do need some help on is UI design/navigation framework, specifically 2 aspects: How do I best implement a fluid design so that the various user controls which filter the map data can be resized/pinned/unpinned (for example, like the Solution Explorer in VS)? I made a test using a Grid with a GridSplitter control, is this the best way? Would it be best to create a Grid/Gridsplitter with Navigation Frames inside the grid to load the content? Since I have multiple user controls that basically use the same set of data, should I set the dataContext at the highest possible level (e.g. if using a grid with multiple frames, at the Grid level?). Any help, tips, links etc. will be very much appreciated!

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  • Product Catalog Schema design

    - by FlySwat
    I'm building a proof of concept schema for a product catalog to possibly replace a very aging and crufty one we use. In our business, we sell both physical materials and services (one time and reoccurring charges). The current catalog schema has each distinct category broken out into individual tables, while this is nicely normalized and performs well, it is fairly difficult to extend. Adding a new attribute to a particular product involves changing the table schema and backpopulating old data. An idea I've been toying with has been something along the line of a base set of entity tables in 3rd normal form, these will contain the facts that are common among ALL products. Then, I'd like to build an Attribute-Entity-Value schema that allows each entity type to be extended in a flexible way using just data and no schema changes. Finally, I'd like to denormalize this data model into materialized views for each individual entity type. This views are what the application would access. We also have many tables that contain business rules and compatibility rules. These would join against the base entity tables instead of the views. My big concerns here are: Performance - Attribute-Entity-Value schemas are flexible, but typically perform poorly, should I be concerned? More Performance - Denormalizing using materialized views may have some risks, I'm not positive on this yet. Complexity - While this schema is flexible and maintainable using just data, I worry that the complexity of the design might make future schema changes difficult. For those who have designed product catalogs for large scale enterprises, am I going down the totally wrong path? Is there any good best practice schema design reading available for product catalogs?

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  • Table Design For SystemSettings, Best Model

    - by Chris L
    Someone suggested moving a table full of settings, where each column is a setting name(or type) and the rows are the customers & their respective settings for each setting. ID | IsAdmin | ImagePath ------------------------------ 12 | 1          | \path\to\images 34 | 0          | \path\to\images The downside to this is every time we want a new setting name(or type) we alter the table(via sql) and add the new (column)setting name/type. Then update the rows(so that each customer now has a value for that setting). The new table design proposal. The proposal is to have a column for setting name and another column for setting. ID | SettingName | SettingValue ---------------------------- 12 | IsAdmin        | 1 12 | ImagePath   | \path\to\images 34 | IsAdmin        | 0 34 | ImagePath   | \path\to\images The point they made was that adding a new setting was as easy as a simple insert statement to the row, no added column. But something doesn't feel right about the second design, it looks bad, but I can't come up with any arguments against it. Am I wrong?

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