Search Results

Search found 23311 results on 933 pages for 'multiple computers'.

Page 290/933 | < Previous Page | 286 287 288 289 290 291 292 293 294 295 296 297  | Next Page >

  • Should I pass a SqlDataReader by reference or not when passing it out to multiple threads.

    - by deroby
    Hi all, being new to c# I've run into this 'conundrum' when passing around a SqlDataReader between different threads. Without going into too much detail, the idea is to have a main thread fetching data from the database (a large recordset) and then have a helper-task run through this record by record and doing some stuff based upon the contents of this. There is no feedback to the recordset, it simply wades through until no records are left. This works fine, but given the nature of the job at hand it should be possible to have this job spread over different threads (CPUs) to maximize throughput (the order of execution is of no significance). The question then becomes, when I pass this recordset in a SqlDataReader, do I have to use ref or not ? It kind of boils down to the question : if I pass the object around without specifying ref, won't it create new copies in memory and have records processed n times ? Or, don't I risk having the record-position being moved forward while not all fields have been fully read yet ? The latter seems more like a 'data racing' issue and probably is covered by the lock()ing mechanism (or not?). My initial take on the problem was that it doesn't really hurt passing the variable using ref, yet as a colleague put it : "you only need ref when you're doing something wrong" =) Additionally using ref restricts me from applying a Using() construction too which isn't very nice either. I thus create a "basic" project that tackles the same approach but without the ref notation. Tests so far show that it works flawlessly on a Core2Duo (2cpu) using any number of threads, yet I'm still a bit wary... What do you experts think about this ? Use ref or not ? You can find the test-project here as it seems I can't upload it to this question directly ?!? ps: it's just a test-project and I'm new to c#, so please be gentle on me when breaking down the code =P

    Read the article

  • What is the fastest way to find duplicates in multiple BIG txt files?

    - by user2950750
    I am really in deep water here and I need a lifeline. I have 10 txt files. Each file has up to 100.000.000 lines of data. Each line is simply a number representing something else. Numbers go up to 9 digits. I need to (somehow) scan these 10 files and find the numbers that appear in all 10 files. And here comes the tricky part. I have to do it in less than 2 seconds. I am not a developer, so I need an explanation for dummies. I have done enough research to learn that hash tables and map reduce might be something that I can make use of. But can it really be used to make it this fast, or do I need more advanced solutions? I have also been thinking about cutting up the files into smaller files. To that 1 file with 100.000.000 lines is transformed into 100 files with 1.000.000 lines. But I do not know what is best: 10 files with 100 million lines or 1000 files with 1 million lines? When I try to open the 100 million line file, it takes forever. So I think, maybe, it is just too big to be used. But I don't know if you can write code that will scan it without opening. Speed is the most important factor in this, and I need to know if it can be done as fast as I need it, or if I have to store my data in another way, for example, in a database like mysql or something. Thank you in advance to anybody that can give some good feedback.

    Read the article

  • How to have Load balanced web services sending messages with nservicebus to multiple subscribers ?

    - by Mrt
    I have load balanced web servers, that with the existing code base, handles when a user logs into the site. I would like to send a broadcast message to any applications that have subscribed saying 'hey x logged in' ? So have many web servers and many applications subscribing. How does discovery work/configuration work with nservicebus ? Should each application know about each web server and subscribe individually or is this where the distributer comes in, so web servers all send to the 1 distributer and all application subscribe to single distributer and the distributer relays the message ? I've tried to research this, but having troubles. Thanks MrT

    Read the article

  • How can I rewrite the history of a published git branch in multiple steps?

    - by Frerich Raabe
    I've got a git repository with two branches, master and amazing_new_feature. The latter branch contains the work on, well, an amazing new feature. A colleague and me are both working on the same repository, and the two of us commit to both branches. Now the work on the amazing new feature finished, and a bit more than 100 commits were accumulated in the amazing_new_feature branch. I'd like to clean those commits up a bit (using git rebase -i) before merging the work into master. The issue we're facing is that it's quite a pain to rewrite/reorder all 100 commits in one go. Instead, what I'd like to do is: Rewrite/merge/reorder the first few commits in the amazing_new_feature branch and put the result into a dedicated branch which contains the 'cleaned up' history (say, a amazing_new_feature_ready_for_merge branch). Rebase the remaining amazing_new_feature branch on the amazing_new_feature_ready_for_merge branch. Repeat at 1. My idea is that at some point, all the work from amazing_new_feature should be in amazing_new_feature_ready_for_merge and then I can merge the latter into master. Is this a sensible approach, or are there better/easier/more fool-proff solutions to this problem? I'm especially scared about the second step of the above algorithm since it means rebasing a published branch. IIRC it's a dangerous thing to do.

    Read the article

  • Big table or multiple separate tables? (database design question)

    - by Khou
    This is a database design question. I want to build an invoice web application, an invoice can have many items, and each user can have an inventory list of product items that they can store and choose to add to an invoice item. My questions are: 1. Should I store all product inventory for all users using my application under one single table? Or have a separate product inventory table created for each user? 2. Is this even possible? 1 table is easier, but what if this single table grows too big, will I have a problem? (primary key INT).

    Read the article

  • How do you create a transaction that spans multiple statements in Python with MySQLdb?

    - by Fast Fish
    I know that with an InnoDB table, transactions are autocommit, however I understand that to mean for a single statement? For example, I want to check if a user exists in a table, and then if it doesn't, create it. However there lies a race condition. I believe using a transaction prior to doing the select, will ensure that the table remains untouched until the subsequent insert, and the transaction is committed. How can you do this with MySQLdb and Python?

    Read the article

  • How do I connect multiple sortable lists to each other in jQuery UI?

    - by Abs
    I'm new to jQuery, and I'm totally struggling with using jQuery UI's sortable. I'm trying to put together a page to facilitate grouping and ordering of items. My page has a list of groups, and each group contains a list of items. I want to allow users to be able to do the following: 1. Reorder the groups 2. Reorder the items within the groups 3. Move the items between the groups The first two requirements are no problem. I'm able to sort them just fine. The problem comes in with the third requirement. I just can't connect those lists to each other. Some code might help. Here's the markup. <ul id="groupsList" class="groupsList"> <li id="group1" class="group">Group 1 <ul id="groupItems1" class="itemsList"> <li id="item1-1" class="item">Item 1.1</li> <li id="item1-2" class="item">Item 1.2</li> </ul> </li> <li id="group2" class="group">Group 2 <ul id="groupItems2" class="itemsList"> <li id="item2-1" class="item">Item 2.1</li> <li id="item2-2" class="item">Item 2.2</li> </ul> </li> <li id="group3" class="group">Group 3 <ul id="groupItems3" class="itemsList"> <li id="item3-1" class="item">Item 3.1</li> <li id="item3-2" class="item">Item 3.2</li> </ul> </li> </ul> I was able to sort the lists by putting $('#groupsList').sortable({}); and $('.itemsList').sortable({}); in the document ready function. I tried using the connectWith option for sortable to make it work, but I failed spectacularly. What I'd like to do is have the every groupItemsX list connected to every groupItemsX list but itself. How should I do that?

    Read the article

  • How can I "merge", "flatten" or "pivot" results from a query which returns multiple rows into a sing

    - by dsm
    I have a simple query over a table, which returns results like the following: id id_type id_ref 2702 5 31 2702 16 14 2702 17 3 2702 40 1 2702 26 4 And I would like to merge the results into a single row, for instance: id concatenation 2702 5,16,17,40,26:31,14,3,1,4 Is there any way to do this within a trigger? NB: I know I can use a cursor, but I would really prefer not to unless there is no better way.

    Read the article

  • What is the recommended way of parsing an XML feed with multiple namespaces with ActionScript 3.0?

    - by dafko
    I have seen the following methods to be used in several online examples, but haven't found any documentation on the recommended way of parsing an XML feed. Method 1: protected function xmlResponseHandler(event:ResultEvent):void { var atom:Namespace = new Namespace("http://www.w3.org/2005/Atom"); var microsoftData:Namespace = new Namespace("http://schemas.microsoft.com/ado/2007/08/dataservices"); var microsoftMetadata:Namespace = new Namespace("http://schemas.microsoft.com/ado/2007/08/dataservices/metadata"); var ac:ArrayCollection = new ArrayCollection(); var keyValuePairs:KeyValuePair; var propertyList:XMLList = (event.result as XML)..atom::entry.atom::content.microsoftMetadata::properties; for each (var properties:XML in propertyList) { keyValuePairs = new KeyValuePair(properties.microsoftData::FieldLocation, properties.microsoftData::Locationid); ac.addItem(keyValuePairs); } cb.dataProvider = ac; } Method 2: protected function xmlResponseHandler(event:ResultEvent):void { namespace atom = "http://www.w3.org/2005/Atom"; namespace d = "http://schemas.microsoft.com/ado/2007/08/dataservices"; namespace m = "http://schemas.microsoft.com/ado/2007/08/dataservices/metadata"; use namespace d; use namespace m; use namespace atom; var ac:ArrayCollection = new ArrayCollection(); var keyValuePairs:KeyValuePair; var propertyList:XMLList = (event.result as XML)..entry.content.properties; for each (var properties:XML in propertyList) { keyValuePairs = new KeyValuePair(properties.FieldLocation, properties.Locationid); ac.addItem(keyValuePairs); } cb.dataProvider = ac; } Sample XML feed: <?xml version="1.0" encoding="iso-8859-1" standalone="yes"?> <feed xml:base="http://www.test.com/Test/my.svc/" xmlns:d="http://schemas.microsoft.com/ado/2007/08/dataservices" xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata" xmlns="http://www.w3.org/2005/Atom"> <title type="text">Test_Locations</title> <id>http://www.test.com/test/my.svc/Test_Locations</id> <updated>2010-04-27T20:41:23Z</updated> <link rel="self" title="Test_Locations" href="Test_Locations" /> <entry> <id>1</id> <title type="text"></title> <updated>2010-04-27T20:41:23Z</updated> <author> <name /> </author> <link rel="edit" title="Test_Locations" href="http://www.test.com/id=1" /> <category term="MySQLModel.Test_Locations" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme" /> <content type="application/xml"> <m:properties> <d:FieldLocation>Test Location</d:FieldLocation> <d:Locationid>test0129</d:Locationid> </m:properties> </content> </entry> <entry> <id>2</id> <title type="text"></title> <updated>2010-04-27T20:41:23Z</updated> <author> <name /> </author> <link rel="edit" title="Test_Locations" href="http://www.test.com/id=2" /> <category term="MySQLModel.Test_Locations" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme" /> <content type="application/xml"> <m:properties> <d:FieldLocation>Yet Another Test Location</d:FieldLocation> <d:Locationid>test25</d:Locationid> </m:properties> </content> </entry> </feed>

    Read the article

  • how can I change top-margin the right way if multiple css class assigned?

    - by Radek
    I assigned these classes menu second_menu menu_about_author to ul so the html code looks like <ul class="menu second_menu menu_about_author"> I wanted this ul to have the same properties like menu and second_menu and then I wanted to move the menu_about_author little bit down. I did so by .menu_about_author { margin-top:40px; } but it didn't work any idea why the margin-top:40px; is crossed? the link to the image is [1]: http://img153.imageshack.us/img153/882/58daeef0c3c846e4a8d6321.png

    Read the article

  • How do I use multiple arguments from an array to construct an execl() call in C?

    - by chucknelson
    I have a string array in C named args[] - now how can I use this list of arguments to construct a proper call to execl()? So if the array contains: {"/bin/ls","ls","-a","-l"} ...how can I eventually construct an execl() call that is: execl("/bin/ls","ls","-a","-l",NULL); I must be thinking about this wrong, as I can't find anything online, just talk about defining functions that can take a variable number of arguments.

    Read the article

  • How do I load multiple FLV files, with the same COMPLETE event handler?

    - by Josamoto
    When loading files with the Loader in ActionScript 3, I am able to inspect the event attribute on the complete event handler to determine what the URL is for the file that has completed downloading. Loader exposes a variable in the event handler attribute: event.target.url which I means that when the handler returns, I can easily determine which file is loading. However, my client has sent numerous FLV files built in After Effects that constitute the UI elements of a Flash application built for them. Loading FLV files require the use of URLLoader, and this does not appear to expose the name of the file being loaded. So I either need to convert the FLV's to SWF, so I can load them as normal. Is there a way to determine the URL inside the onComplete event handler fired by URLLoader?

    Read the article

  • How can I make CAPTCHA work across multiple pages?

    - by jm04469
    Ever visit a website such as myspace where they leverage CAPTCHA to prevent spam? The typical pattern is to present a challenge to each URL that is opened, yet the challenge doesn't actually belong to the page itself which causes additional bandwidth usage. So, if I open up six pages at the same time and want to present a challenge on each page. I want the challenge to be tied to the page and not to the session. How can I make this work with Spring and/or Struts.

    Read the article

  • IF I have multiple candidate keys which one is a primary key and justify your choice ??

    - by zahrani
    Given R = { Account , Analyst , Assets, Broker, Client, Commission, Company, Dividend, Exchange, Investment, Office, Profile, Return, Risk_profile, Stock, Volume} and a set of functional dependencies F{fd1, fd2,fd3, fd4, fd5,fd6, fd7, fd8, fd9, fd10, fd11} where: fd1: Client - Office fd2: Stock - Exchange, Dividend fd3: Broker - Profile fd4: Company - Stock fd5: Client - Risk_profile, Analyst fd6: Analyst - Broker fd7: Stock, Broker - Invenstment, Volume fd8: Stock - Company fd9: Investment,Commission - Return fd10: Stock, Broker - Client fd11: Account - Assests these are candidate key(s) : (Account, Commission,Analyst ,Company) (Account, Commission,Analyst ,Stock) (Account ,Commission,Broker ,Company) (Account ,Commission,Broker ,Stock) (Account ,Commission,Client, Company) (Account ,Commission,Client ,Stock) (Q) Select a primary key and justify your choice ? I was select (Account ,Commission,Broker ,Stock) as a primary key ??? I chose that because it has the most direct dependencies compared to other ones. e.g. more attributes are functionally dependent on this primary key. please check if my answer is it true ? or Not I'm waiting your answer asap thank you

    Read the article

  • Numpy array, how to select indices satisfying multiple conditions?

    - by Bob
    Suppose I have a numpy array x = [5, 2, 3, 1, 4, 5], y = ['f', 'o', 'o', 'b', 'a', 'r']. I want to select the elements in y corresponding to elements in x that are greater than 1 and less than 5. I tried x = array([5, 2, 3, 1, 4, 5]) y = array(['f','o','o','b','a','r']) output = y[x > 1 & x < 5] # desired output is ['o','o','b','a'] but this doesn't work. How would I do this?

    Read the article

  • QT NOOB: Add action handler for multiple objects of same type.

    - by what
    I have a simple QT application with 10 radio buttons with names radio_1 through radio_10. It is a ui called Selector, and is part of a class called TimeSelector In my header file for this design, i have this: //! [1] class TimeSelector : public QWidget { Q_OBJECT public: TimeSelector(QWidget *parent = 0); private slots: //void on_inputSpinBox1_valueChanged(int value); //void on_inputSpinBox2_valueChanged(int value); private: Ui::Selector ui; }; //! [1] the commented out void_on_inputSpinBox1_valueChanged(int value) is from the tutorial for the simple calculator. I know i can do: void on_radio_1_valueChanged(int value); but I would need 10 functions. I want to be able to make one function that works for everything, and lets me pass in maybe a name of the radio button that called it, or a reference to the radio button so i can work with it and determine who it was. I am very new to QT but this seems like it should be very basic and doable, thanks.

    Read the article

  • Android/Eclipse: Creating multiple builds with different com identifiers.

    - by Dave
    Hi, I have an app that requires two builds - one is a demo app, the other uses the same codebase but uses a flag to introduce different functionality. The identifier must be different each time (e.g. com.siteA.appA and com.siteB.appB). However it doesn't appear to be trivial to use the refactor functionality in Eclipse to change the com identifier - all references change apart from the "import com.siteA.appA.R" reference. Is there a way to create different builds with different com identifiers/app name within Eclipse? Thanks

    Read the article

  • How do I set up for sharing code (ASP.NET) across multiple domain names?

    - by Scott J.
    I have built a website and now the customer wants to split it between three different domains. What is the best way to do this? This is what I have so far. c:/website1/ points to www.website1.com c:/website1/vd1/ points to www.website2.com c:/website1/vd2/ points to www.website3.com The webhost I'm working with has done it the following way, but now I'm getting a bunch of errors that seems like it's not seeing the App_code folder. Do I need to make a lot of changes? How does this affect the location references?

    Read the article

  • Is the C++ compiler optimizer allowed to break my destructor ability to be called multiple times?

    - by sharptooth
    We once had an interview with a very experienced C++ developer who couldn't answer the following question: is it necessary to call the base class destructor from the derived class destructor in C++? Obviously the answer is no, C++ will call the base class destructor automagically anyway. But what if we attempt to do the call? As I see it the result will depend on whether the base class destructor can be called twice without invoking erroneous behavior. For example in this case: class BaseSafe { public: ~BaseSafe() { } private: int data; }; class DerivedSafe { public: ~DerivedSafe() { BaseSafe::~BaseSafe(); } }; everything will be fine - the BaseSafe destructor can be called twice safely and the program will run allright. But in this case: class BaseUnsafe { public: BaseUnsafe() { buffer = new char[100]; } ~BaseUnsafe () { delete[] buffer; } private: char* buffer; }; class DerivedUnsafe { public: ~DerivedUnsafe () { BaseUnsafe::~BaseUnsafe(); } }; the explicic call will run fine, but then the implicit (automagic) call to the destructor will trigger double-delete and undefined behavior. Looks like it is easy to avoid the UB in the second case. Just set buffer to null pointer after delete[]. But will this help? I mean the destructor is expected to only be run once on a fully constructed object, so the optimizer could decide that setting buffer to null pointer makes no sense and eliminate that code exposing the program to double-delete. Is the compiler allowed to do that?

    Read the article

  • Computer Invisible On Domain

    - by Giawa
    Good afternoon, I'm sorry that this isn't a programming question specifically, but stackoverflow has been great at answering questions in the past, so I thought I'd give it a shot. One of our Linux users attempted to install Cygwin on our Windows Server 2008 Domain Controller. Now it is no longer possible to browse the domain and see all of the computers. For example, \\my_domain_name will just bring up a username/password dialog box (that will not accept any username or password, even the domain administrator) and no computers will ever be listed. However, I can still connect to computers based on their name or IP address. So \\eridanus or \\192.168.1.85 still work to connect to the shared directories of computers on our network. Does anyone know where I can find these settings? and how I can fix this problem? Thanks, Giawa

    Read the article

< Previous Page | 286 287 288 289 290 291 292 293 294 295 296 297  | Next Page >