Search Results

Search found 4081 results on 164 pages for 'qt mfc migration'.

Page 73/164 | < Previous Page | 69 70 71 72 73 74 75 76 77 78 79 80  | Next Page >

  • Which file is the COM++ object and how do I import it to .NET?

    - by Bad Man
    I'm trying to write a COM++ object wrapper around a Qt widget (control) I wrote so I can use it in future .NET projects. e.g.: public __gc class comWidget; In the compile directory are the .exe, an exe.intermediate.manifest, and the comWidget.obj, and also some other crap files (.pdb, etc). So what/how do I import into .NET? I feel like I'm missing an important step for registering the object or whatever, but all these tutorials are terrible outdated and ridiculously unhelpful (for instance, I'm using the old CLR syntax because I can't find any good docs on the new stuff, thx again M$ for being lazy faggots as usual)

    Read the article

  • Linkage Error with Inherited Class

    - by metdos
    I have static library and another program which uses it. In the static library If I define header without inheretence it works fine. class TcpCommunication On the other hand If I use inheretence with a QT class, class TcpCommunication:public QTcpServer I'm getting linkage error when I compiling code which uses this static library. >MStoDKAPId.lib(TcpCommunication.obj) : error LNK2019: unresolved external symbol "__declspec(dllimport) public: virtual __thiscall QTcpServer::~QTcpServer(void)" (__imp_??1QTcpServer@@UAE@XZ) referenced in function "public: virtual __thiscall TcpCommunication::~TcpCommunication(void)" (??1TcpCommunication@@UAE@XZ) What can be the problem? Thanks.

    Read the article

  • How to Optimize Combined Graphical Operations?

    - by Sunny
    Hi, Here is a Scenario, A series of operations that I will call for painting, QPainter p(this); 1). p.fillRect(0,0,320,240, RED_COLOR) 2) p.drawLine(0,0,100,100, BLUE_COLOR) 3) p.fillRect(0,0,320,240, YELLOW_COLOR) Now I want that painter should not draw first FillRect Function. It should not draw line. It should only perform last operation. Is there any way to achive this optimization in Qt. Is this type of drawing/painting optimizations are supported by any library?

    Read the article

  • whats wrong with this piece of code for saving contacts

    - by Shadow
    Hi, i am using the latest Nokia Qt SDK. i have tried to add the contacts, its not getting added.. what is missing here.. // Construct contact manager for default contact backend QContactManager* cm = new QContactManager("simulator"); // QContactManager* cm = new QContactManager("memory"); // i tried this, its also not working // Create example contact QContact example; // Add contact name QContactName name; name.setFirstName("John"); name.setLastName("Doe"); example.saveDetail(&name); // Add contact email address //QContactEmailAddress email; // email.setContexts(QContactDetail::ContextHome); //email.setEmailAddress(“[email protected]”); // example.saveDetail(&email); // Finally, save the contact details cm->saveContact(&example); delete cm; Thanks

    Read the article

  • How to detect an active x component that does not respond any more?

    - by koschi
    My application is written in C++ and uses the Qt framework. I use the QAxWidget class to access an active x component. Now I need some kind of mechanism that notifies my application each time the active x component has crashed or does not respond any more (due to dead lock or infinite loop). (1) can easily been done by watching the external process of the active x component. But maybe there is a more elegant approach? But how can (2) be implemented?

    Read the article

  • How to pass a function to a function?

    - by ShaChris23
    Suppose I have a class with 2 static functions: class CommandHandler { public: static void command_one(Item); static void command_two(Item); }; I have a problem DRY problem where I have 2 functions that have the exact same code for every single line, except for the function that it calls: void CommandOne_User() { // some code A CommandHandler::command_one(item); // some code B } void CommandTwo_User() { // some code A CommandHandler::command_two(item); // some code B } I would like to remove duplication, and, ideally, do something like this: void CommandOne_User() { Function func = CommandHandler::command_one(); Refactored_CommandUser(func); } void CommandTwo_User() { Function func = CommandHandler::command_one(); Refactored_CommandUser(func); } void Refactored_CommandUser(Function func) { // some code A func(item); } I have access to Qt, but not Boost. Could someone help suggest a way on how I can refactor something like this?

    Read the article

  • How to implement the "Edit" menu with "Undo", "Cut", "Paste" and "Copy"?

    - by BastiBense
    Greetings, for one of my applications I'm trying to implement an "Edit" menu. This menu usually has the standard-entries Undo, Cut, Copy and Paste. This menu is not there by default, and users seem to expect it especially on Mac OS X. Is there a an easier way of implementing this, without doing so in every widget manually? Since most widgets have the copy/paste/undo mechanism already implemented via shortcuts, I'd like to provide a few simple menu actions that call them as well. The actions should call whatever widget has the focus first, then they should pass the events upwards the object chain, I guess. I'm using Qt 4.6 on Windows, Linux and Mac OS X. Thanks!

    Read the article

  • How to get tag parameter value with XQuery

    - by uni
    For example i have this xml. I need to get value of parameter val of tag foo with id="two" <top> <sub id="one"> <foo id="two" val="bar" /> sometext </sub> </top> Whis this query (using Qt QXmlQuery): doc('test.xml')/top/sub[@id='one']/foo[@id='two']/<p>{@val}</p> I receive <p val="bar"/>, but I need only text "bar" without any tags. I tried to remove <p> and </p> and receive syntax error, unexpected { How can i get parameter value without any tags?

    Read the article

  • What is the correct way to customize Icon and Text position of items in a QListView?

    - by petermcg
    I'm using C++ and Qt's (4.6) model/view framework and wondering what is the correct way to change the display of items in a QListView or a class derived from QListView from: to: I'm not concerned about the sort order or Flow, I'm interested in the best way to correctly position the text to the right of the icon. If this can only be done by writing a custom QStyledItemDelegate that's totally fine, I want to rule out whether this is the correct approach or whether it's best to look at setLayout or similar, example code would help. The example application I'm looking at is the 'interview' example from qtdemo which amongst other things displays icons and text in a QListView.

    Read the article

  • How to check that a regular expression fall into infty loop or not?

    - by Sorush Rabiee
    I'm trying to learn and hopefully use regular expression with Qt. I found that some patterns cause handler to fall into loop. for example searching \b\b in a text, never will terminate. and number of these expressions is infinite (\b\b\b,\b\b\b\b and so on). I'd like to determine and control all invalid expressions. Is there an algorithm to distinguish valid and invalid expressions? If not, how can I prevent my program from falling into an infinite loop?

    Read the article

  • Numeric GUI bottleneck

    - by Physic
    Hi all, I've made a GUI to set up and start a numerical integrator using PyQT4, Wing, QT, and Python 2.6.6, on my Mac. The thing is, when I run the integrator form the GUI, it takes very many times longer than when I crudely run the integrator from the command line. As an example, a 1000 year integration took 98 seconds on the command line and ~570 seconds from the GUI. In the GUI, the integration runs from a thread and then returns. It uses a a queue to communicate back to the GUI. Does anyone have any ideas as to where the bottleneck is? I suspect that others may be experiencing something like this just on a smaller scale. t = threading.Thread( target=self.threadsafe_start_thread, args=( self.queue, self.selected ) ) t.start() Thanks!

    Read the article

  • qmake library reordering

    - by user1095108
    I put this into a qmake file: QTPLUGIN += component LIBS += -L../lib -lmodule -lcomponent -lnetworking But qmake reorders the libraries behind my back: g++ -m64 -Wl,-O1,--sort-common,--as-needed,-z,relro -o testb .obj/constants.o .obj/main.o .obj/qrc_application.o -L/usr/lib -L../lib -lmodule -lnetworking -lcomponent -lQtGui -lQtNetwork -lQtCore -lpthread Probably because component is a static plugin. But it has a static dependency on the networking library and hence the reordering causes a link error. It is a static dependency and hence is ok in my opinion. How to work around this? I'm using qt 4.8.1.

    Read the article

  • How to force calling of QWidget::paintEvent() when its hovered by other window?

    - by Pie_Jesu
    Hi there. I have occured a problem: I'm writing a widget, which displays current date's day number. It's like a button, but it's not derived from QPushButton class. Just from QWidget. So I reimplemented enterEvent(), leaveEvent(), mousePressEvent(), mouseReleaseEvent(). I call update() inside these methods and widget has realistic button behavior (paintEvent() is reimplemented too). But when I change system date and hover that widget with other window, my widget doesn't calls paintEvent() and displays old date. Only when I place mouse over it, widget repaints it's contents. I guess there is an option, which paints old contents on hover event to avoid unnecessary paint events. But I need to disable it. Tried to set many attributes (Qt::WidgetAttribute enum). But it doesn't helps. Please, help me (and sorry for my bad english).

    Read the article

  • CSC folder data access AND roaming profiles issues (Vista with Server 2003, then 2008)

    - by Alex Jones
    I'm a junior sysadmin for an IT contractor that helps small, local government agencies, like little towns and the like. One of our clients, a public library with ~ 50 staff users, was recently migrated from Server 2003 Standard to Server 2008 R2 Standard in a very short timeframe; our senior employee, the only network engineer, had suddenly put in his two weeks notice, so management pushed him to do this project before quitting. A bit hasty on management's part? Perhaps. Could we do anything about that? Nope. Do I have to fix this all by myself? Pretty much. The network is set up like this: a) 50ish staff workstations, all running Vista Business SP2. All staff use MS Outlook, which uses RPC-over-HTTPS ("Outlook Anywhere") for cached Exchange access to an offsite location. b) One new (virtualized) Server 2008 R2 Standard instance, running atop a Server 2008 R2 host via Hyper-V. The VM is the domain's DC, and also the site's one and only file server. Let's call that VM "NEWBOX". c) One old physical Server 2003 Standard server, running the same roles. Let's call it "OLDBOX". It's still on the network and accessible, but it's been demoted, and its shares have been disabled. No data has been deleted. c) Gigabit Ethernet everywhere. The organization's only has one domain, and it did not change during the migration. d) Most users were set up for a combo of redirected folders + offline files, but some older employees who had been with the organization a long time are still on roaming profiles. To sum up: the servers in question handle user accounts and files, nothing else (eg, no TS, no mail, no IIS, etc.) I have two major problems I'm hoping you can help me with: 1) Even though all domain users have had their redirected folders moved to the new server, and loggin in to their workstations and testing confirms that the Documents/Music/Whatever folders point to the new paths, it appears some users (not laptops or anything either!) had been working offline from OLDBOX for a long time, and nobody realized it. Here's the ugly implication: a bunch of their data now lives only in their CSC folders, because they can't access the share on OLDBOX and sync with it finally. How do I get this data out of those CSC folders, and onto NEWBOX? 2) What's the best way to migrate roaming profile users to non-roaming ones, without losing vital data like documents, any lingering PSTs, etc? Things I've thought about trying: For problem 1: a) Reenable the documents share on OLDBOX, force an Offline Files sync for ALL domain users, then copy OLDBOX's share's data to the equivalent share on NEWBOX. Reinitialize the Offline Files cache for every user. With this: How do I safely force a domain-wide Offline Files sync? Could I lose data by reenabling the share on OLDBOX and forcing the sync? Afterwards, how can I reinitialize the Offline Files cache for every user, without doing it manually, workstation by workstation? b) Determine which users have unsynced changes to OLDBOX (again, how?), search each user's CSC folder domain-wide via workstation admin shares, and grab the unsynched data. Reinitialize the Offline Files cache for every user. With this: How can I detect which users have unsynched changes with a script? How can I search each user's CSC folder, when the ownership and permissions set for CSC folders are so restrictive? Again, afterwards, how can I reinitialize the Offline Files cache for every user, without doing it manually, workstation by workstation? c) Manually visit each workstation, copy the contents of the CSC folder, and manually copy that data onto NEWBOX. Reinitialize the Offline Files cache for every user. With this: Again, how do I 'break into' the CSC folder and get to its data? As an experiment, I took one workstation's HD offsite, imaged it for safety, and then tried the following with one of our shop PCs, after attaching the drive: grant myself full control of the folder (failed), grant myself ownership of the folder (failed), run chkdsk on the whole drive to make sure nothing's messed up (all OK), try to take full control of the entire drive (failed), try to take ownership of the entire drive (failed) MS KB articles and Googling around suggests there's a utility called CSCCMD that's meant for this exact scenario...but it looks like it's available for XP, not Vista, no? Again, afterwards, how can I reinitialize the Offline Files cache for every user, without doing it manually, workstation by workstation? For problem 2: a) Figure out which users are on roaming profiles, and where their profiles 'live' on the server. Create new folders for them in the redirected folders repository, migrate existing data, and disable the roaming. With this: Finding out who's roaming isn't hard. But what's the best way to disable the roaming itself? In AD Users and Computers, or on each user's workstation? Doing it centrally on the server seems more efficient; that said, all of the KB research I've done turns up articles on how to go from local to roaming, not the other way around, so I don't have good documentation on this. In closing: we have good backups of NEWBOX and OLDBOX, but not of the workstations themselves, so anything drastic on the client side would need imaging and testing for safety. Thanks for reading along this far! Hopefully you can help me dig us out of this mess.

    Read the article

  • Migrate from Oracle to MySQL

    - by Cassy
    Hi together. We ran into serious performance problems with our Oracle database and we would like to try to migrate to a MySQL-based database (either MySQL directly or, more preferrable, Infobright). The thing is, we need to let the old and the new system overlap for at least some weeks if not months, before we actually know, if all features of the new database match our needs. So, here is our situation: The Oracle database consists of multiple tables with each millions of rows. During the day, there are literally thousands of statements, which we cannot stop for migration. Every morning, new data is imported into the Oracle database, replacing some thousands of rows. Copying this process is not a problem, so we could, in theory, import in both databases in parallel. But, and here lies the challenge, for this to work, we need to have an export from the Oracle database with a consistent state from one day. (We cannot export some tables on Monday and some others on Tuesday, etc.) This means, that at least the export should be finished in less than one day. Our first thought was to dump the schema, but I wasn't able to find a tool to import an Oracle dump file into mysql. Exporting tables in CSV files might work, but I'm afraid it could take too long. So my question now is: What should I do? Is there any tool to import Oracle dump files into MySQL? Does anybody have any experience with such a large-scale migration? Thanks in advance, Cassy PS: Please, don't suggest performance optimization techniques for Oracle, we already tried a lot :-)

    Read the article

  • Html.EditorFor, Html.DisplayFor not working on MVC1.0 -> MVC2.0 manual migration

    - by lawrence-chase
    Has anyone encountered this problem? I manually migrated a MVC1.0 application to MVC2.0 and everything so far seems to be working fine. Today I wanted to try out the Html.EditorFor helper and it doesn't render the template. I set it up the same way in a fresh MVC2.0 application and the template does render. Is there anything other (or specifically needed when mirgrating to activate this behavior) than throwing the partial view like DateTime.ascx into Views/Shared/EditorTemplates and using the helper methods to render the model objects? I'm stumped.

    Read the article

  • msdeploy IIS 6 to 7 migration issue

    - by rboorgapally
    I am trying to view the dependencies of my website on IIS 6.0 running on windows server 2003. When I type the following command, msdeploy -verb:getDependencies -source:metakey=lm/w3svc/1 I got the following error: C:\Program Files\IIS\Microsoft Web Deploy>msdeploy -verb:getDependencies -source :metakey=lm/w3svc/1 Error: Object of type 'metaKey' and path 'lm/w3svc/1' cannot be created Error: The metabase key '/lm/w3svc/1' could not be found. Error: Access is denied. (Exception from HRESULT: 0x80070005 (E_ACCESSDENIED)) Error count: 1 Can any one explain these to me?

    Read the article

  • iPhone - Core Data crash on migration

    - by Sergey Zenchenko
    I have problems, when i install app from Xcode all works but if I build app and install it from iTunes I have an error with the database at launch. This happens only than i have changes in the core data model and need to migrate to a new version. At first launch at crashes with message: Thread 0: 0 libSystem.B.dylib 0x00034588 pwrite + 20 1 libsqlite3.dylib 0x000505ec _sqlite3_purgeEligiblePagerCacheMemory + 2808 2 libsqlite3.dylib 0x000243d8 sqlite3_backup_init + 7712 3 libsqlite3.dylib 0x000244ac sqlite3_backup_init + 7924 4 libsqlite3.dylib 0x0000d418 sqlite3_file_control + 4028 5 libsqlite3.dylib 0x000228b4 sqlite3_backup_init + 764 6 libsqlite3.dylib 0x00022dd0 sqlite3_backup_init + 2072 7 libsqlite3.dylib 0x000249a8 sqlite3_backup_init + 9200 8 libsqlite3.dylib 0x00029800 sqlite3_open16 + 11360 9 libsqlite3.dylib 0x0002a200 sqlite3_open16 + 13920 10 libsqlite3.dylib 0x0002ab84 sqlite3_open16 + 16356 11 libsqlite3.dylib 0x00049418 sqlite3_prepare16 + 54056 12 libsqlite3.dylib 0x00002940 sqlite3_step + 44 13 CoreData 0x00011958 _execute + 44 14 CoreData 0x000113e0 -[NSSQLiteConnection execute] + 696 15 CoreData 0x000994be -[NSSQLConnection prepareAndExecuteSQLStatement:] + 26 16 CoreData 0x000be14c -[_NSSQLiteStoreMigrator performMigration:] + 244 17 CoreData 0x000b6c60 -[NSSQLiteInPlaceMigrationManager migrateStoreFromURL:type:options:withMappingModel:toDestinationURL:destinationType:destinationOptions:error:] + 1040 18 CoreData 0x000aceb0 -[NSStoreMigrationPolicy(InternalMethods) migrateStoreAtURL:toURL:storeType:options:withManager:error:] + 92 19 CoreData 0x000ad6f0 -[NSStoreMigrationPolicy migrateStoreAtURL:withManager:metadata:options:error:] + 72 20 CoreData 0x000ac9ee -[NSStoreMigrationPolicy(InternalMethods) _gatherDataAndPerformMigration:] + 880 21 CoreData 0x0000965c -[NSPersistentStoreCoordinator addPersistentStoreWithType:configuration:URL:options:error:] + 1328 At next launches app doesn't loads data from database.

    Read the article

  • UpdateModel() fails after migration from MVC 1.0 to MVC 2.0

    - by Alastair Pitts
    We are in the process of migrating our ASP.NET MVC 1.0 web app to MVC 2.0 but we have run into a small snag. In our report creation wizard, it is possible leave the Title text box empty and have it be populated with a generic title (in the post action). The code that does the update on the model of the Title is: if (TryUpdateModel(reportToEdit, new[] { "Title" })) { //all ok here try to create (custom validation and attach to graph to follow) //if title is empty get config subject if (reportToEdit.Title.Trim().Length <= 0) reportToEdit.Title = reportConfiguration.Subject; if (!_service.CreateReport(1, reportToEdit, SelectedUser.ID, reportConfigID, reportCategoryID, reportTypeID, deviceUnitID)) return RedirectToAction("Index"); } In MVC 1.0, this works correctly,the reportToEdit has an empty title if the textbox is empty, which is then populated with the Subject property. In MVC 2.0 this fails/returns false. If I add the line above: UpdateModel(reportToEdit, new[] { "Title" }); it throws System.InvalidOperationException was unhandled by user code Message="The model of type 'Footprint.Web.Models.Reports' could not be updated." Source="System.Web.Mvc" StackTrace: at System.Web.Mvc.Controller.UpdateModel[TModel](TModel model, String prefix, String[] includeProperties, String[] excludeProperties, IValueProvider valueProvider) at System.Web.Mvc.Controller.UpdateModel[TModel](TModel model, String[] includeProperties) at Footprint.Web.Controllers.ReportsController.Step1(FormCollection form) in C:\TFS Workspace\ExtBusiness_Footprint\Branches\apitts_uioverhaul\Footprint\Footprint.Web\Controllers\ReportsController.cs:line 398 at lambda_method(ExecutionScope , ControllerBase , Object[] ) at System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters) at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters) at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters) at System.Web.Mvc.ControllerActionInvoker.<>c__DisplayClassd.<InvokeActionMethodWithFilters>b__a() at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation) InnerException: Reading the MVC2 Release notes I see this breaking change: Every property for model objects that use IDataErrorInfo to perform validation is validated, regardless of whether a new value was set. In ASP.NET MVC 1.0, only properties that had new values set would be validated. In ASP.NET MVC 2, the Error property of IDataErrorInfo is called only if all the property validators were successful. but I'm confused how this is affecting me. I'm using the entity framework generated classes. Can anyone pinpoint why this is failing?

    Read the article

  • Any Flex 4 migration experience?

    - by Gok Demir
    My current development stack is MySQL + iBatis + Spring + Spring BlazeDS Integration 1.01 + BlazeDS 3.2 and Flex 3 with Mate 0.8.9 framework. Now Flash Builder 4 beta 2 is out. There are cool features like Data Centric Development (DCD), form generation etc... Do you know how Spring Blazeds Integration works with BlazeDS 4? What about Mate? Is there any issues with Flex 4 ? How DCD suits with mate eventmaps. I know it is better to try it out myself but I just want to check if somebody ever tried to migrate Flex 4. If so what are the issues? Did you notice any productivity speed up? Thanks.

    Read the article

  • sqlalchemy date type in 0.6 migration using mssql

    - by nosklo
    I'm connection to mssql server through pyodbc, via FreeTDS odbc driver, on linux ubuntu 10.04. Sqlalchemy 0.5 uses DATETIME for sqlalchemy.Date() fields. Now Sqlalchemy 0.6 uses DATE, but sql server 2000 doesn't have a DATE type. How can I make DATETIME be the default for sqlalchemy.Date() on sqlalchemy 0.6 mssql+pyodbc dialect? I'd like to keep it as clean as possible. Here's code to reproduce the issue: import sqlalchemy from sqlalchemy import Table, Column, MetaData, Date, Integer, create_engine engine = create_engine( 'mssql+pyodbc://sa:sa@myserver/mydb?driver=FreeTDS') m = MetaData(bind=engine) tb = sqlalchemy.Table('test_date', m, Column('id', Integer, primary_key=True), Column('dt', Date()) ) tb.create() And here is the traceback I'm getting: Traceback (most recent call last): File "/tmp/teste.py", line 15, in <module> tb.create() File "/home/nosklo/.local/lib/python2.6/site-packages/sqlalchemy/schema.py", line 428, in create bind.create(self, checkfirst=checkfirst) File "/home/nosklo/.local/lib/python2.6/site-packages/sqlalchemy/engine/base.py", line 1647, in create connection=connection, **kwargs) File "/home/nosklo/.local/lib/python2.6/site-packages/sqlalchemy/engine/base.py", line 1682, in _run_visitor **kwargs).traverse_single(element) File "/home/nosklo/.local/lib/python2.6/site-packages/sqlalchemy/sql/visitors.py", line 77, in traverse_single return meth(obj, **kw) File "/home/nosklo/.local/lib/python2.6/site-packages/sqlalchemy/engine/ddl.py", line 58, in visit_table self.connection.execute(schema.CreateTable(table)) File "/home/nosklo/.local/lib/python2.6/site-packages/sqlalchemy/engine/base.py", line 1157, in execute params) File "/home/nosklo/.local/lib/python2.6/site-packages/sqlalchemy/engine/base.py", line 1210, in _execute_ddl return self.__execute_context(context) File "/home/nosklo/.local/lib/python2.6/site-packages/sqlalchemy/engine/base.py", line 1268, in __execute_context context.parameters[0], context=context) File "/home/nosklo/.local/lib/python2.6/site-packages/sqlalchemy/engine/base.py", line 1367, in _cursor_execute context) File "/home/nosklo/.local/lib/python2.6/site-packages/sqlalchemy/engine/base.py", line 1360, in _cursor_execute context) File "/home/nosklo/.local/lib/python2.6/site-packages/sqlalchemy/engine/default.py", line 277, in do_execute cursor.execute(statement, parameters) sqlalchemy.exc.ProgrammingError: (ProgrammingError) ('42000', '[42000] [FreeTDS][SQL Server]Column or parameter #2: Cannot find data type DATE. (2715) (SQLExecDirectW)') '\nCREATE TABLE test_date (\n\tid INTEGER NOT NULL IDENTITY(1,1), \n\tdt DATE NULL, \n\tPRIMARY KEY (id)\n)\n\n' ()

    Read the article

  • Django data migration when changing a field to ManyToMany

    - by Ken H
    I have a Django application in which I want to change a field from a ForeignKey to a ManyToManyField. I want to preserve my old data. What is the simplest/best process to follow for this? If it matters, I use sqlite3 as my database back-end. If my summary of the problem isn't clear, here is an example. Say I have two models: class Author(models.Model): author = models.CharField(max_length=100) class Book(models.Model): author = models.ForeignKey(Author) title = models.CharField(max_length=100) Say I have a lot of data in my database. Now, I want to change the Book model as follows: class Book(models.Model): author = models.ManyToManyField(Author) title = models.CharField(max_length=100) I don't want to "lose" all my prior data. What is the best/simplest way to accomplish this? Ken

    Read the article

  • Custom Workflow migration to Windows Workflow foundation

    - by ASV
    I have an application that runs workflows custom developed in .Net 3.5. Now we want to build a case (to help customer understand) for migrating these custom workflows to WF. What should be the highlights of such a case? P.N: the customer has not asked for it but we want to build a case and present it to the customer. Thanks in advance ASV

    Read the article

  • Large number of simultaneous long-running operations in Qt

    - by Hostile Fork
    I have some long-running operations that number in the hundreds. At the moment they are each on their own thread. My main goal in using threads is not to speed these operations up. The more important thing in this case is that they appear to run simultaneously. I'm aware of cooperative multitasking and fibers. However, I'm trying to avoid anything that would require touching the code in the operations, e.g. peppering them with things like yieldToScheduler(). I also don't want to prescribe that these routines be stylized to be coded to emit queues of bite-sized task items...I want to treat them as black boxes. For the moment I can live with these downsides: Maximum # of threads tend to be O(1000) Cost per thread is O(1MB) To address the bad cache performance due to context-switches, I did have the idea of a timer which would juggle the priorities such that only idealThreadCount() threads were ever at Normal priority, with all the rest set to Idle. This would let me widen the timeslices, which would mean fewer context switches and still be okay for my purposes. Question #1: Is that a good idea at all? One certain downside is it won't work on Linux (docs say no QThread::setPriority() there). Question #2: Any other ideas or approaches? Is QtConcurrent thinking about this scenario? (Some related reading: how-many-threads-does-it-take-to-make-them-a-bad-choice, many-threads-or-as-few-threads-as-possible, maximum-number-of-threads-per-process-in-linux)

    Read the article

< Previous Page | 69 70 71 72 73 74 75 76 77 78 79 80  | Next Page >