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  • AVAudioPlayer not unloading cached memory after each new allocation

    - by Rob
    I am seeing in Instruments that when I play a sound via the standard "AddMusic" example method that Apple provides, it allocates 32kb of memory via the prepareToPlay call (which references the AudioToolBox framework's Cache_DataSource::ReadBytes function) each time a new player is allocated (i.e. each time a different sound is played). However, that cached data never gets released. This obviously poses a huge problem if it doesn't get released and you have a lot of sound files to play, since it tends to keep allocating memory and eventually crashes if you have enough unique sound files (which I unfortunately do). Have any of you run across this or what am I doing wrong in my code? I've had this issue for a while now and it's really bugging me since my code is verbatim of what Apple's is (I think). How I call the function: - (void)playOnce:(NSString *)aSound { // Gets the file system path to the sound to play. NSString *soundFilePath = [[NSBundle mainBundle] pathForResource:aSound ofType:@"caf"]; // Converts the sound's file path to an NSURL object NSURL *soundURL = [[NSURL alloc] initFileURLWithPath: soundFilePath]; self.soundFileURL = soundURL; [soundURL release]; AVAudioPlayer * newAudio=[[AVAudioPlayer alloc] initWithContentsOfURL: soundFileURL error:nil]; self.theAudio = newAudio; // automatically retain audio and dealloc old file if new m4a file is loaded [newAudio release]; // release the audio safely // this is where the prior cached data never gets released [theAudio prepareToPlay]; // set it up and play [theAudio setNumberOfLoops:0]; [theAudio setVolume: volumeLevel]; [theAudio setDelegate: self]; [theAudio play]; } and then theAudio gets released in the dealloc method of course.

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  • Why qry.post executed with asynchronous mode?

    - by Ryan
    Recently I met a strange problem, see code snips as below: var sqlCommand: string; connection: TADOConnection; qry: TADOQuery; begin connection := TADOConnection.Create(nil); try connection.ConnectionString := 'Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Test.MDB;Persist Security Info=False'; connection.Open(); qry := TADOQuery.Create(nil); try qry.Connection := connection; qry.SQL.Text := 'Select * from aaa'; qry.Open; qry.Append; qry.FieldByName('TestField1').AsString := 'test'; qry.Post; beep; finally qry.Free; end; finally connection.Free; end; end; First, Create a new access database named test.mdb and put it under the directory of this test project, we can create a new table named aaa in it which has only one text type field named TestField1. We set a breakpoint at line of "beep", then lunch the test application under ide debug mode, when ide stops at the breakpoint line (qry.post has been executed), at this time we use microsoft access to open test.mdb and open table aaa you will find there are no any changes in table aaa, if you let the ide continue running after pressing f9 you can find a new record is inserted in to table aaa, but if you press ctrl+f2 to terminate the application at the breakpoint, you will find the table aaa has no record been inserted, but in normal circumstance, a new record should be inserted in to the table aaa after qry.post executed. who can explain this problem , it troubles me so long time. thanks !!! BTW, the ide is delphi 2010, and the access mdb file is created by microsoft access 2007 under windows 7

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  • Foreign key not working in MySQL: Why can I INSERT a value that's not in the foreign column?

    - by stalepretzel
    I've created a table in MySQL: CREATE TABLE actions ( A_id int NOT NULL AUTO_INCREMENT, type ENUM('rate','report','submit','edit','delete') NOT NULL, Q_id int NOT NULL, U_id int NOT NULL, date DATE NOT NULL, time TIME NOT NULL, rate tinyint(1), PRIMARY KEY (A_id), CONSTRAINT fk_Question FOREIGN KEY (Q_id) REFERENCES questions(P_id), CONSTRAINT fk_User FOREIGN KEY (U_id) REFERENCES users(P_id)); This created the table I wanted just fine (although a "DESCRIBE actions;" command showed me that the foreign keys were keys of type MUL, and I'm not sure what this means). However, when I try to enter a Q_id or a U_id that does not exist in the questions or users tables, MySQL still allows these values. What did I do wrong? How can I prevent a table with a foreign key from accepting invalid data? If I add TYPE=InnoDB to the end, I get an error: ERROR 1005 (HY000): Can't create table './quotes/actions.frm' (errno: 150) Why might that happen? I'm told that it's important to enforce data integrity with functional foreign keys, but also that InnoDB should not be used with MySQL. What do you recommend?

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  • Testing a Gui-heavy WPF application.

    - by Hamish Grubijan
    We (my colleagues) have a messy 12 y.o. mature app that is GUI-based, and the current plan is to add new dialogs & other GUI in WPF, as well as replace some of the older dialogs in WPF as well. At the same time we wish to be able to test that Monster - GUI automation in a maintainable way. Some challenges: The application is massive. It constantly gains new features. It is being changed around (bug fixes, patches). It has a back end, and a layer in-between. The state of it can get out of whack if you beat it to death. What we want is: Some tool that can automate testing of WPF. auto-discovery of what the inputs and the outputs of the dialog are. An old test should still work if you add a label that does nothing. It should fail, however, if you remove a necessary text field. It would be very nice if the test suite was easy to maintain, if it ran and did not break most of the time. Every new dialog should be created with testability in mind. At this point I do not know exactly what I want, so I am marking this as a community wiki. If having to test a huge GUI-based app rings the bell (even if not in WPF), then please share your good, bad and ugly experiences here.

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  • ScrollView content async downloading problem

    - by Newbee
    Hi! I have UIScrollView with lots of UIImageView inside. In the loadView method I assign some temporary image for each of subview UIImageView images and starts several threads to async download images from internet. Each thread downloads and assign images as follows: NSData *data = [NSData dataWithContentsOfURL:URL]; UIImage *img = [UIImage imageWithData:data]; img_view.image = img; Here is the problem - I expects picture will changed after each image downloaded by I can see only temporary images until all images will downloads. UIScrollView still interact while images downloads - I can scroll temporary images inside it and see scrollers and nothing blocks run loop, but downloaded images doesn't updates.. What I tried to do: Call sleep() in the download thread -- not helps. Call setNeedsDisplay for each ImageView inside ScrollView and for ScrollView -- not helps. What's wrong ? Thanks. Update. I tried some experiments with number of threads and number of images to download. Now I'm sure -- images redraws only when thread finished. For example - if I load 100 images with one thread -- picture updates one time after all images downloads. If I increase number of threads to 10 -- picture updates 10 times -- 10 images appears per update. One more update. I fixed problem by staring new thread from the downloading threads each time one image downloaded and exit current thread (instead of download several images in one thread in the cycle and exit thread only when all downloaded). Obviously it's not a good solution and there must be right approach.

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  • PHP ZipArchive Empty in IE

    - by Jesse Bunch
    Hi, I am using PHP's ZipArchive class to create a zip file containing photos and then serve it up to the browser for download. Here is my code: /** * Grabs the order, packages the files, and serves them up for download. * * @param string $intEntryID * @return void * @author Jesse Bunch */ public static function download_order_by_entry_id($intUniqueID) { $objCustomer = PhotoCustomer::get_customer_by_unique_id($intUniqueID); if ($objCustomer): if (!class_exists('ZipArchive')): trigger_error('ZipArchive Class does not exist', E_USER_ERROR); endif; $objZip = new ZipArchive(); $strZipFilename = sprintf('%s/application/tmp/%s-%s.zip', $_SERVER['DOCUMENT_ROOT'], $objCustomer->getEntryID(), time()); if ($objZip->open($strZipFilename, ZIPARCHIVE::CREATE) !== TRUE): trigger_error('Unable to create zip archive', E_USER_ERROR); endif; foreach($objCustomer->arrPhotosRequested as $objPhoto): $filename = PhotoCart::replace_ee_file_dir_in_string($objPhoto->strHighRes); $objZip->addFile($filename,sprintf('/press_photos/%s-%s', $objPhoto->getEntryID(), basename($filename))); endforeach; $objZip->close(); header('Last-Modified: '.gmdate('D, d M Y H:i:s', filemtime($strZipFilename)).' GMT', TRUE, 200); header('Cache-Control: no-cache', TRUE); header('Pragma: Public', TRUE); header('Expires: ' . gmdate('D, d M Y H:i:s', time()) . ' GMT', TRUE); header('Content-Length: '.filesize($strZipFilename), TRUE); header('Content-disposition: attachment; filename=press_photos.zip', TRUE); header('Content-Type: application/octet-stream', TRUE); ob_start(); readfile($strZipFilename); ob_end_flush(); exit; else: trigger_error('Invalid Customer', E_USER_ERROR); endif; } This code works really well with all browsers but IE. In IE, the file downloads correctly, but the zip archive is empty. When trying to extract the files, Windows tells me that the zip archive is corrupt. Has anyone had this issue before?

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  • Natural vs surrogate keys on support tables

    - by Bugeo
    I have read many articles about the battle between natural versus surrogate primary keys. I agree in the use of surrogate keys to identify records of tables whose contents are created by the user. But in the case of supporting tables what should I use? For example, in a hypothetical table "orderStates". If you use a natural key would have the following data: TABLE ORDERSTATES {ID: "NEW", NAME: "New"} {ID: "MANAGEMENT" NAME: "Management"} {ID: "SHIPPED" NAME: "Shipped"} If I use a surrogate key would have the following data: TABLE ORDERSTATES {ID: 1 CODE: "NEW", NAME: "New"} {ID: 2 CODE: "MANAGEMENT" NAME: "Management"} {ID: 3 CODE: "SHIPPED" NAME: "Shipped"} Now let's take an example: a user enters a new order. In the case in which use natural keys, in the code I can write this: newOrder.StateOrderId = "NEW"; With the surrogate keys instead every time I have an additional step. stateOrderId_NEW = .... I retrieve the id corresponding to the recod code "NEW" newOrder.StateOrderId = stateOrderId_NEW; The same will happen every time I have to move the order in a new status. So, in this case, what are the reason to chose one key type vs the other one?

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  • Do you use Styrofoam balls to model your systems?

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

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  • Passive and active sockets

    - by davsan
    Quoting from this socket tutorial: Sockets come in two primary flavors. An active socket is con­nect­ed to a remote active socket via an open data con­nec­tion... A passive socket is not con­nect­ed, but rather awaits an in­com­ing con­nec­tion, which will spawn a new active socket once a con­nec­tion is es­tab­lished ... Each port can have a single passive socket binded to it, await­ing in­com­ing con­nec­tions, and mul­ti­ple active sockets, each cor­re­spond­ing to an open con­nec­tion on the port. It's as if the factory worker is waiting for new mes­sages to arrive (he rep­re­sents the passive socket), and when one message arrives from a new sender, he ini­ti­ates a cor­re­spon­dence (a con­nec­tion) with them by del­e­gat­ing someone else (an active socket) to ac­tu­al­ly read the packet and respond back to the sender if nec­es­sary. This permits the factory worker to be free to receive new packets. ... Then the tutorial explains that, after a connection is established, the active socket continues receiving data until there are no remaining bytes, and then closes the connection. What I didn't understand is this: Suppose there's an incoming connection to the port, and the sender wants to send some little data every 20 minutes. If the active socket closes the connection when there are no remaining bytes, does the sender have to reconnect to the port every time it wants to send data? How do we persist a once established connection for a longer time? Can you tell me what I'm missing here? My second question is, who determines the limit of the concurrently working active sockets?

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  • I can't figure out why this fps counter is inaccurate.

    - by rmetzger
    I'm trying to track frames per second in my game. I don't want the fps to show as an average. I want to see how the frame rate is affected when I push keys and add models etc. So I am using a variable to store the current time and previous time, and when they differ by 1 second, then I update the fps. My problem is that it is showing around 33fps but when I move the mouse around really fast, the fps jumps up to 49fps. Other times, if I change a simple line of code elsewhere not related to the frame counter, or close the project and open it later, the fps will be around 60. Vsync is on so I can't tell if the mouse is still effecting the fps. Here is my code which is in an update function that happens every frame: FrameCount++; currentTime = timeGetTime (); static unsigned long prevTime = currentTime; TimeDelta = (currentTime - prevTime) / 1000; if (TimeDelta > 1.0f) { fps = FrameCount / TimeDelta; prevTime = currentTime; FrameCount = 0; TimeDelta = 0; } Here are the variable declarations: int FrameCount; double fps, currentTime, prevTime, TimeDelta, TimeElapsed; Please let me know what is wrong here and how to fix it, or if you have a better way to count fps. Thanks!!!!!! I am using DirectX 9 btw but I doubt that is relevant, and I am using PeekMessage. Should I be using an if else statement instead? Here is my message processing loop: MSG msg; ZeroMemory (&msg, sizeof (MSG)); while (msg.message != WM_QUIT) { if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) { TranslateMessage (&msg); DispatchMessage (&msg); } Update (); RenderFrame (); }

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  • Mysql Database Question about Large Columns

    - by murat
    Hi, I have a table that has 100.000 rows, and soon it will be doubled. The size of the database is currently 5 gb and most of them goes to one particular column, which is a text column for PDF files. We expect to have 20-30 GB or maybe 50 gb database after couple of month and this system will be used frequently. I have couple of questions regarding with this setup 1-) We are using innodb on every table, including users table etc. Is it better to use myisam on this table, where we store text version of the PDF files? (from memory usage /performance perspective) 2-) We use Sphinx for searching, however the data must be retrieved for highlighting. Highlighting is done via sphinx API but still we need to retrieve 10 rows in order to send it to Sphinx again. This 10 rows may allocate 50 mb memory, which is quite large. So I am planning to split these PDF files into chunks of 5 pages in the database, so these 100.000 rows will be around 3-4 million rows and couple of month later, instead of having 300.000-350.000 rows, we'll have 10 million rows to store text version of these PDF files. However, we will retrieve less pages, so again instead of retrieving 400 pages to send Sphinx for highlighting, we can retrieve 5 pages and it will have a big impact on the performance. Currently, when we search a term and retrieve PDF files that have more than 100 pages, the execution time is 0.3-0.35 seconds, however if we retrieve PDF files that have less than 5 pages, the execution time reduces to 0.06 seconds, and it also uses less memory. Do you think, this is a good trade-off? We will have million of rows instead of having 100k-200k rows but it will save memory and improve the performance. Is it a good approach to solve this problem and do you have any ideas how to overcome this problem? The text version of the data is used only for indexing and highlighting. So, we are very flexible. Thanks,

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  • php, user-uploaded files, version control, and website deployment

    - by user151841
    I have a website that I regularly update the code to. I keep it in version control. When I want to deploy a new version of the site, I do an export and then symlink the served directory name to the directory of the deployment. There is a place where users can upload files, and I noticed once that, after I had deployed a new version, the user files were gone! Of course, I hadn't added them to the repository, and since the served site was from an export, they weren't uploaded into a version-controlled directory anyways. PHP doesn't yet have integrated svn functionality, so I couldn't do much programmatically to user uploaded files. My solution was to create an additional website, files.website.com, which sits in a parallel directory to the served website, and is served out of a directory that is under version control. That way they don't get obliterated when I do an upgrade to the website. From time to time, I manually add uploaded files to the svn project, deleted user-deleted ones, and commit the new version. I'm working on a shell script to run from cron to do this, but it isn't my forte, so it's on the backburner as it's not a pressing need. Is there a better way to do this?

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  • Synchronizing screencasting (ffmpeg) and capturing from the webcam (OpenCV)

    - by lyuba
    As from my previous questions, I am trying to build a simple eye tracker. Decided to start from a Linux version (run Ubuntu). To complete this task one should organize screencasting and webcam capturing in such way that frames from both streams exactly match each other and there is the same number of frames in each of them totally. Screencasting fsp fully depends on the camera's fsp, so each time we get the image from the webcam we can potentially grab a screen frame and stay happy. However, all the tools for the fast screencasting, like ffmpeg, for example, return the .avi file as the result and require the fsp already known to be started. From the other side, tools like Java+Robot or ImageMagick seem to require around 20ms to return the .jpg screenshot, which is pretty slow for the task. But they may be requested right after each time the webcam frame is grabbed and provide the needed synchronization. So the sub-questions are: 1. Does the USD camera's frame rate vary during a single session? 2. Are there any tools which provide fast screencasting frame by frame? 3. Is there any way to make ffmpeg push a new frame to the .avi file only when program initiates this request? For my task I may either use C++ or Java. I am, actually, an interface designer, not the driver programmer, and this task seems to be pretty low-level. I would be grateful for any suggestion and tip!

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  • SQL Server database change workflow best practices

    - by kubi
    The Background My group has 4 SQL Server Databases: Production UAT Test Dev I work in the Dev environment. When the time comes to promote the objects I've been working on (tables, views, functions, stored procs) I make a request of my manager, who promotes to Test. After testing, she submits a request to an Admin who promotes to UAT. After successful user testing, the same Admin promotes to Production. The Problem The entire process is awkward for a few reasons. Each person must manually track their changes. If I update, add, remove any objects I need to track them so that my promotion request contains everything I've done. In theory, if I miss something testing or UAT should catch it, but this isn't certain and it's a waste of the tester's time, anyway. Lots of changes I make are iterative and done in a GUI, which means there's no record of what changes I made, only the end result (at least as far as I know). We're in the fairly early stages of building out a data mart, so the majority of the changes made, at least count-wise, are minor things: changing the data type for a column, altering the names of tables as we crystallize what they'll be used for, tweaking functions and stored procs, etc. The Question People have been doing this kind of work for decades, so I imagine there have got to be a much better way to manage the process. What I would love is if I could run a diff between two databases to see how the structure was different, use that diff to generate a change script, use that change script as my promotion request. Is this possible? If not, are there any other ways to organize this process? For the record, we're a 100% Microsoft shop, just now updating everything to SQL Server 2008, so any tools available in that package would be fair game.

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  • iPhone application update (using Core Data on Sqlite)

    - by owen
    I have an app which is using Core Data on Sqlite, Now I have a update which has some DB structure changes say adding a new table I know when an app get updated, it updates the app binary only, nothing on document directory will be changed. When the app gets updated and launchs at the first time and run [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:[self managedObjectModel]]; It will find the difference between the data model and DB structure in Sqlite and will throw an exception and quit. Error: "The model used to open the store is incompatible with the one used to create the store" So, can anyone here give me some idea how to update an app when there is a DB structure change? I think we can run a DB script to create that new table when it launchs the update at the first time. But if there are other changes like changing the type of some fields or deleting some fields, and we need to migrate the old data, this is really a headache. In this case, Is the only way to do is creating a new app? Is there anyone tried something similar like this?

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  • How can I prevent/make it hard to download my flash video?

    - by Billy
    I want to at least prevent normal users to download my flash video. What's the best way to do it? Create a httphandler, add a token (e.g. timeid), set the cache control to no-cache so that only the users with correct token can view the correct video. Is that feasible? It is the requirement from client that the video should not be downloaded by users and should be watched only in the particular website. I want to know if this works: http://www.somesite.com/video.swf?time=1248319067 Server will generate a token(time in the above example) so that user can only have one request to this link. If the user wants to watch the video again, he needs to go to our website to get the token again. Is this okay to prevent novices from downloading? I can't download this flash video by the downloadHelper firefox plugin: http://news.bbc.co.uk/2/hi/americas/8164177.stm Updated (13:49 pm 2009/07/23): The above file can be downloaded using some video download software. The video files of following Chinese sites are well protected (I can't download it using many video download software): http://programme.tvb.com/drama/abrideforaride/video/ Do you know how it is done?

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  • Winsock tcp/ip Socket listening but connection refused, race condition?

    - by Wayne
    Hello folks. This involves two automated unit tests which each start up a tcp/ip server that creates a non-blocking socket then bind()s and listen()s in a loop on select() for a client that connects and downloads some data. The catch is that they work perfectly when run separately but when run as a test suite, the second test client will fail to connect with WSACONNREFUSED... UNLESS there is a Thread.Sleep() of several seconds between them??!!! Interestingly, there is retry loop every 1 second for connecting after any failure. So the second test loops for a while until timeout after 10 minutes. During that time, netstat -na shows the correct port number is in the LISTEN state for the server socket. So if it is in the listen state? Why won't it accept the connection? In the code, there are log messages that show the select NEVER even gets a socket ready to read (which means ready to accept a connection when it applies to a listening socket). Obviously the problem must be related to some race condition between finishing one test which means close() and shutdown() on each end of the socket, and the start up of the next. This wouldn't be so bad if the retry logic allowed it to connect eventually after a couple of seconds. However it seems to get "gummed up" and won't even retry. However, for some strange reason the listening socket SAYS it's in the LISTEN state even through keeps refusing connections. So that means it's the Windoze O/S which is actually catching the SYN packet and returning a RST packet (which means "Connection Refused"). The only other time I ever saw this error was when the code had a problem that caused hundreds of sockets to get stuck in TIME_WAIT state. But that's not the case here. netstat shows only about a dozen sockets with only 1 or 2 in TIME_WAIT at any given moment. Please help.

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  • Oracle command hangs when using view for "WHILE x IN..." subquery

    - by Calvin Fisher
    I'm working on a web service that fetches data from an oracle data source in chunks and passes it back to an indexing/search tool in XML format. I'm the C#/.NET guy, and am kind of fuzzy on parts of Oracle. Our Oracle team gave us the following script to run, and it works well: SELECT ROWID, [columns] FROM [table] WHERE ROWID IN ( SELECT ROWID FROM ( SELECT ROWID FROM [table] WHERE ROWID > '[previous_batch_last_rowid]' ORDER BY ROWID ) WHERE ROWNUM <= 10000 ) ORDER BY ROWID 10,000 rows is an arbitrary but reasonable chunk size and ROWID is sufficiently unique for our purposes to use as a UID since each indexing run hits only one table at a time. Bracketed values are filled in programmatically by the web service. Now we're going to start adding views to the indexing, each of which will union a few separate tables. Since ROWID would no longer function as a unique identifier, they added a column to the views (VIEW_UNIQUE_ID) that concatenates the ROWIDs from the component tables to construct a UID for each union. But this script does not work, even though it follows the same form as the previous one: SELECT VIEW_UNIQUE_ID, [columns] FROM [view] WHERE VIEW_UNIQUE_ID IN ( SELECT VIEW_UNIQUE_ID FROM ( SELECT VIEW_UNIQUE_ID FROM [view] WHERE ROWID > '[previous_batch_last_view_unique_id]' ORDER BY VIEW_UNIQUE_ID ) WHERE ROWNUM <= 10000 ) ORDER BY VIEW_UNIQUE_ID It hangs indefinitely with no response from the Oracle server. I've waited 20+ minutes and the SQLTools dialog box indicating a running query remains the same, with no progress or updates. I've tested each subquery independently and each works fine and takes a very short amount of time (<= 1 second), so the view itself is sound. But as soon as the inner two SELECT queries are added with "WHERE VIEW_UNIQUE_ID IN...", it hangs. Why doesn't this query work for views? In what important way are they not interchangeable here?

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  • How to reuse results with a schema for end of day stock-data

    - by Vishalrix
    I am creating a database schema to be used for technical analysis like top-volume gainers, top-price gainers etc.I have checked answers to questions here, like the design question. Having taken the hint from boe100 's answer there I have a schema modeled pretty much on it, thusly: Symbol - char 6 //primary Date - date //primary Open - decimal 18, 4 High - decimal 18, 4 Low - decimal 18, 4 Close - decimal 18, 4 Volume - int Right now this table containing End Of Day( EOD) data will be about 3 million rows for 3 years. Later when I get/need more data it could be 20 million rows. The front end will be asking requests like "give me the top price gainers on date X over Y days". That request is one of the simpler ones, and as such is not too costly, time wise, I assume. But a request like " give me top volume gainers for the last 10 days, with the previous 100 days acting as baseline", could prove 10-100 times costlier. The result of such a request would be a float which signifies how many times the volume as grown etc. One option I have is adding a column for each such result. And if the user asks for volume gain in 10 days over 20 days, that would require another table. The total such tables could easily cross 100, specially if I start using other results as tables, like MACD-10, MACD-100. each of which will require its own column. Is this a feasible solution? Another option being that I keep the result in cached html files and present them to the user. I dont have much experience in web-development, so to me it looks messy; but I could be wrong ( ofc!) . Is that a option too? Let me add that I am/will be using mod_perl to present the response to the user. With much of the work on mysql database being done using perl. I would like to have a response time of 1-2 seconds.

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  • Django notification get date one accesses a link

    - by dana
    hi there, i'm making a notification system, so that a user in a virtual community to be announced when someone sends him a message, or starts following him (the follow relation is like a friend relation, but it is not necessarily reciprocal) my view function: def notification_view(request, last_checked): u = Relation.objects.filter(date_follow>Notification.objects.get(last_checked=last_checked)) v = Message.objects.filter(date>Notification.objects.get(last_checked=last_checked)) if u: notification_type = follow if notice_settings == receive_notification or notice_settings == only_follow following = u if v: notification_type = message if notice_settings == receive_notification or notice_settings == only_messages message = v return render_to_response('notification/notification.html', { 'following': following, 'message':message, }, context_instance=RequestContext(request)) the models.py: class NoticeType(models.Model): follow = models.ForeignKey(Relations, editable = False) message = models.ForeignKey(Messages) classroom_invitation = models.ForeignKey(Classroom) class Notification(models.Model): receiver = models.ForeignKey(User, editable=False) date = models.DateTimeField(auto_now=True, editable = False) notice_type = models.ForeignKey(NoticeType, editable = False, related_name = "notification_type") sent = models.BooleanField(default = True) last_checked = models.DateTimeField(auto_now=True, editable = False) class NotificationSettings(models.Model): user = models.ForeignKey(User) receive_notifications = models.BooleanField(default = True) only_follow = models.BooleanField(default = False) only_message = models.BooleanField(default = False) only_classroom = models.BooleanField(default = False) #receive_on_email = models.BooleanField(default = False) my problem is: i want last_checked to be the time when someone acceses a link (the notification link). How can i possibily save that time? how can i get it? thanks in avance!

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  • How is a referencing environment generally implemented for closures?

    - by Alexandr Kurilin
    Let's say I have a statically/lexically scoped language with deep binding and I create a closure. The closure will consist of the statements I want executed plus the so called referencing environment, or, to quote this post, the collection of variables which can be used. What does this referencing environment actually look like implementation-wise? I was recently reading about ObjectiveC's implementation of blocks, and the author suggests that behind the scenes you get a copy of all of the variables on the stack and also of all the references to heap objects. The explanation claims that you get a "snapshot" of the referencing environment at the point in time of the closure's creation. Is that more or less what happens, or did I misread that? Is anything done to "freeze" a separate copy of the heap objects, or is it safe to assume that if they get modified between closure creation and the closure executing, the closure will no longer be operating on the original version of the object? If indeed there's copying being made, are there memory usage considerations in situations where one might want to create plenty of closures and store them somewhere? I think that misunderstanding of some of these concepts might lead to tricky issues like the ones Eric Lippert mentions in this blog post. It's interesting because you'd think that it wouldn't make sense to keep a reference to a value type that might be gone by the time the closure is called, but I'm guessing that in C# the compiler will figure out that the variable is needed later and put it into the heap instead. It seems that in most memory-managed languages everything is a reference and thus ObjectiveC is a somewhat unique situation with having to deal with copying what's on the stack.

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  • NSTimer to smooth out playback position

    - by Michael
    I have an audio player and I want to show the current time of the the playback. I'm using a custom play class. The app downloads the mp3 to a file then plays from the file when 5% has been downloaded. I have a progress view update as the file plays and update a label on each call to the progress view. However, this is jerky... sometimes even going backward a digit or two. I was considering using an NSTimer to smooth things out. I would be fired every second to a method and pass the percentage played figure to the method then update the label. First, does this seem reasonable? Second, how do I pass the percentage (a float) over to the target of the timer. Right now I am putting the percent played into a dictionary but this seems less than optimal. This is what is called update the progress bar: -(void)updateAudioProgress:(Percentage)percent { audio = percent; if (!seekChanging) slider.value = percent; NSMutableDictionary *myDictionary = [[NSMutableDictionary alloc] init]; [myDictionary setValue:[NSNumber numberWithFloat:percent] forKey:@"myPercent"]; [NSTimer scheduledTimerWithTimeInterval:5 target:self selector:@selector(myTimerMethod:) userInfo:myDictionary repeats:YES]; [myDictionary release]; } This is called first after 5 seconds but then updates each time the method is called. As always, comments and pointers appreciated.

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  • Cannot implicity convert type void to System.Threading.Tasks.Task<bool>

    - by sagesky36
    I have a WCF Service that contains the following method. All the methods in the service are asynchrounous and compile just fine. public async Task<Boolean> ValidateRegistrationAsync(String strUserName) { try { using (YeagerTechEntities DbContext = new YeagerTechEntities()) { DbContext.Configuration.ProxyCreationEnabled = false; DbContext.Database.Connection.Open(); var reg = await DbContext.aspnet_Users.FirstOrDefaultAsync(f => f.UserName == strUserName); if (reg != null) return true; else return false; } } catch (Exception) { throw; } } My client application was set to access the WCF service with the check box for the "Allow generation of asynchronous operations" and it generated the proxy just fine. I am receiving the above subject error when trying to call this WCF service method from my client with the following code. Mind you, I know what the error message means, but this is my first time trying to call an asynchronous task in a WCF service from a client. Task<Boolean> blnMbrShip = db.ValidateRegistrationAsync(FormsAuthentication.Decrypt(cn.Value).Name); What do I need to do to properly call the method so the design time compile error disappears? Thanks so much in advance...

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  • visusal studio embedded crystal report keeps prompting database login?

    - by phill
    I'm using visual studio 2005 to develop a form with a combobox passing a value into the parameter of an embedded crystal report. I'm trying to figure out why it keeps prompting me for a database login every single time you try to run the report with a different combobox selection. Here is my code: private Sub Form1_load... Dim ConnName As String Dim ServerName As String Dim DBName As String Dim user As String Dim pass As String Dim gDBA As ADODB.Connection Dim records As ADODB.Recordset Dim datver As ADODB.Recordset Dim query As String '---OPEN THE DATABASE CONNECTIONS gDBA = New ADODB.Connection ': gDBA.CursorLocation = adUseServer 'Added to prevent time out error gDBA.CommandTimeout = 1000 : gDBA.ConnectionTimeout = 1000 gDBA.ConnectionString = "Server=svr13;Database=subscribers;User ID=KViews;Password=Solution;Trusted_Connection=True;" gDBA.Open("Data Source=Kaseya;Initial Catalog=subscribers;User Id=KViews;Password=Solution;", "KViews", "Solution") records = New ADODB.Recordset query = "select distinct groupname from _v_k order by groupname desc" 'records.ActiveConnection = gDBA.ConnectionString records.CursorType = CursorTypeEnum.adOpenForwardOnly records.LockType = LockTypeEnum.adLockReadOnly records.Open(query, gDBA) Do While Not records.EOF ComboBox1.Items.Add(records.Fields("groupname").Value) records.MoveNext() Loop end Sub Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim selected As String selected = ComboBox1.Text Dim cryRpt As New ReportDocument cryRpt.Load("C:\Visual Studio 2005\Projects\WindowsApplication1\WindowsApplication1\CrystalReport1.rpt") cryRpt.SetDatabaseLogon("KViews", "Solutions", "svr13", "subscribers") cryRpt.SetParameterValue("companyname", selected) CrystalReportViewer1.ReportSource = cryRpt CrystalReportViewer1.Refresh() End Sub I looked at this previous posting http://stackoverflow.com/questions/1132314/database-login-prompt-with-crystal-reports but this wasn't very helpful. I couldn't find where a CMC was to disable the prompt. Any ideas? thanks in advance

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  • Problems setting up AuthLogic

    - by sscirrus
    Hi all, I'm trying to set up a simple login using AuthLogic into my User table. Every time I try, the login fails and I don't know why. I'm sure this is a simple error but I've been hitting a brick wall with it for a while. #user_sessions_controller def create @user_session = UserSession.new(params[:user_session]) if @user_session.save flash[:notice] = "Login successful!" else flash[:notice] = "We couldn't log you in. Please try again!" redirect_to :controller => "index", :action => "index" end end #_user_login.html.erb (this is the partial from my index page where Users log in) <% form_tag user_session_path do %> <p><label for="login">Login:</label> <%= text_field_tag "login", nil, :class => "inputBox", :id => "login", </p> <p><label for="password">Password: </label> <%= password_field_tag "password", nil, :class => "inputBox", :id => "password", </p> <p><%= submit_tag "submit", :class => "submit" %></p> <% end %> I had Faker generate some data for my user table but I cannot log in! Every time I try it just redirects to index. Where am I going wrong? Thanks everybody.

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