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  • MySQL create stored procedure fails but all internal queries succeed alone?

    - by Mark
    Hi all, I just created a simple database in MySQL, and I am learning how to write stored proc's. I'm familiar with M$SQL and as far as I can see the following should work: use mydb; -- -------------------------------------------------------------------------------- -- Routine DDL -- -------------------------------------------------------------------------------- DELIMITER // CREATE PROCEDURE mydb.doStats () BEGIN CREATE TABLE IF NOT EXISTS resultprobability ( ballNumber INT NOT NULL , probability FLOAT NULL, PRIMARY KEY (ballNumber) ); CREATE TABLE IF NOT EXISTS drawProbability ( drawDate DATE NOT NULL , ball1 INT NULL , ball2 INT NULL , ball3 INT NULL , ball4 INT NULL , ball5 INT NULL , ball6 INT NULL , ball7 INT NULL , score FLOAT NULL , PRIMARY KEY (drawDate) ); TRUNCATE TABLE resultprobability; TRUNCATE TABLE drawprobability; INSERT INTO resultprobability (ballNumber, probability) (select resultset.ballNumber ballNumber,(count(0)/(select count(0) from resultset)) probability from resultset group by resultset.ballNumber); INSERT INTO drawProbability (drawDate, ball1, ball2, ball3, ball4, ball5, ball6, ball7, score) (select distinct r.drawDate, a.ballnumber ball1, b.ballnumber ball2, c.ballnumber ball3, d.ballnumber ball4, e.ballnumber ball5, f.ballnumber ball6,g.ballnumber ball7, ((a.probability + b.probability + c.probability + d.probability + e.probability + f.probability + g.probability)/7) score from resultset r inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 1) a on a.drawdate = r.drawDate inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 2) b on b.drawdate = r.drawDate inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 3) c on c.drawdate = r.drawDate inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 4) d on d.drawdate = r.drawDate inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 5) e on e.drawdate = r.drawDate inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 6) f on f.drawdate = r.drawDate inner join (select r.drawDate, r.ballNumber, p.probability from resultset r inner join resultprobability p on p.ballNumber = r.ballNumber where r.appearence = 7) g on g.drawdate = r.drawDate order by score desc); END // DELIMITER ; instead i get the following Executed successfully in 0.002 s, 0 rows affected. Line 1, column 1 Error code 1064, SQL state 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '' at line 26 Line 6, column 1 Error code 1064, SQL state 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ')) probability from resultset group by resultset.ballNumber); INSERT INTO d' at line 1 Line 31, column 51 Error code 1064, SQL state 42000: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ') score from resultset r inner join (select r.drawDate, r.ballNumber, p.probabi' at line 1 Line 39, column 114 Execution finished after 0.002 s, 3 error(s) occurred. What am I doing wrong? I seem to have exhausted my limited mental abilities!

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  • Slow performance when utilizing Interop.DSOFile to search files by Custom Document Property

    - by Gradatc
    I am new to the world of VB.NET and have been tasked to put together a little program to search a directory of about 2000 Excel spreadsheets and put together a list to display based on the value of a Custom Document Property within that spreadsheet file. Given that I am far from a computer programmer by education or trade, this has been an adventure. I've gotten it to work, the results are fine. The problem is, it takes well over a minute to run. It is being run over a LAN connection. When I run it locally (using a 'test' directory of about 300 files) it executes in about 4 seconds. I'm not sure even what to expect as a reasonable execution speed, so I thought I would ask here. The code is below, if anyone thinks changes there might be of use in speeding things up. Thank you in advance! Private Sub listByPt() Dim di As New IO.DirectoryInfo(dir_loc) Dim aryFiles As IO.FileInfo() = di.GetFiles("*" & ext_to_check) Dim fi As IO.FileInfo Dim dso As DSOFile.OleDocumentProperties Dim sfilename As String Dim sheetInfo As Object Dim sfileCount As String Dim ifilesDone As Integer Dim errorList As New ArrayList() Dim ErrorFile As Object Dim ErrorMessage As String 'Initialize progress bar values ifilesDone = 0 sfileCount = di.GetFiles("*" & ext_to_check).Length Me.lblHighProgress.Text = sfileCount Me.lblLowProgress.Text = 0 With Me.progressMain .Maximum = di.GetFiles("*" & ext_to_check).Length .Minimum = 0 .Value = 0 End With 'Loop through all files in the search directory For Each fi In aryFiles dso = New DSOFile.OleDocumentProperties sfilename = fi.FullName Try dso.Open(sfilename, True) 'grab the PT Initials off of the logsheet Catch excep As Runtime.InteropServices.COMException errorList.Add(sfilename) End Try Try sheetInfo = dso.CustomProperties("PTNameChecker").Value Catch ex As Runtime.InteropServices.COMException sheetInfo = "NONE" End Try 'Check to see if the initials on the log sheet 'match those we are searching for If sheetInfo = lstInitials.SelectedValue Then Dim logsheet As New LogSheet logsheet.PTInitials = sheetInfo logsheet.FileName = sfilename PTFiles.Add(logsheet) End If 'update progress bar Me.progressMain.Increment(1) ifilesDone = ifilesDone + 1 lblLowProgress.Text = ifilesDone dso.Close() Next lstResults.Items.Clear() 'loop through results in the PTFiles list 'add results to the listbox, removing the path info For Each showsheet As LogSheet In PTFiles lstResults.Items.Add(Path.GetFileNameWithoutExtension(showsheet.FileName)) Next 'build error message to display to user ErrorMessage = "" For Each ErrorFile In errorList ErrorMessage += ErrorFile & vbCrLf Next MsgBox("The following Log Sheets were unable to be checked" _ & vbCrLf & ErrorMessage) PTFiles.Clear() 'empty PTFiles for next use End Sub

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  • C# Confusing Results from Performance Test

    - by aip.cd.aish
    I am currently working on an image processing application. The application captures images from a webcam and then does some processing on it. The app needs to be real time responsive (ideally < 50ms to process each request). I have been doing some timing tests on the code I have and I found something very interesting (see below). clearLog(); log("Log cleared"); camera.QueryFrame(); camera.QueryFrame(); log("Camera buffer cleared"); Sensor s = t.val; log("Sx: " + S.X + " Sy: " + S.Y); Image<Bgr, Byte> cameraImage = camera.QueryFrame(); log("Camera output acuired for processing"); Each time the log is called the time since the beginning of the processing is displayed. Here is my log output: [3 ms]Log cleared [41 ms]Camera buffer cleared [41 ms]Sx: 589 Sy: 414 [112 ms]Camera output acuired for processing The timings are computed using a StopWatch from System.Diagonostics. QUESTION 1 I find this slightly interesting, since when the same method is called twice it executes in ~40ms and when it is called once the next time it took longer (~70ms). Assigning the value can't really be taking that long right? QUESTION 2 Also the timing for each step recorded above varies from time to time. The values for some steps are sometimes as low as 0ms and sometimes as high as 100ms. Though most of the numbers seem to be relatively consistent. I guess this may be because the CPU was used by some other process in the mean time? (If this is for some other reason, please let me know) Is there some way to ensure that when this function runs, it gets the highest priority? So that the speed test results will be consistently low (in terms of time). EDIT I change the code to remove the two blank query frames from above, so the code is now: clearLog(); log("Log cleared"); Sensor s = t.val; log("Sx: " + S.X + " Sy: " + S.Y); Image<Bgr, Byte> cameraImage = camera.QueryFrame(); log("Camera output acuired for processing"); The timing results are now: [2 ms]Log cleared [3 ms]Sx: 589 Sy: 414 [5 ms]Camera output acuired for processing The next steps now take longer (sometimes, the next step jumps to after 20-30ms, while the next step was previously almost instantaneous). I am guessing this is due to the CPU scheduling. Is there someway I can ensure the CPU does not get scheduled to do something else while it is running through this code?

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  • PHP: Can pcntl_alarm() and socket_select() peacefully exist in the same thread?

    - by DWilliams
    I have a PHP CLI script mostly written that functions as a chat server for chat clients to connect to (don't ask me why I'm doing it in PHP, thats another story haha). My script utilizes the socket_select() function to hang execution until something happens on a socket, at which point it wakes up, processes the event, and waits until the next event. Now, there are some routine tasks that I need performed every 30 seconds or so (check of tempbanned users should be unbanned, save user databases, other assorted things). From what I can tell, PHP doesn't have very great multi-threading support at all. My first thought was to compare a timestamp every time the socket generates an event and gets the program flowing again, but this is very inconsistent since the server could very well sit idle for hours and not have any of my cleanup routines executed. I came across the PHP pcntl extensions, and it lets me use assign a time interval for SIGALRM to get sent and a function get executed every time it's sent. This seems like the ideal solution to my problem, however pcntl_alarm() and socket_select() clash with each other pretty bad. Every time SIGALRM is triggered, all sorts of crazy things happen to my socket control code. My program is fairly lengthy so I can't post it all here, but it shouldn't matter since I don't believe I'm doing anything wrong code-wise. My question is: Is there any way for a SIGALRM to be handled in the same thread as a waiting socket_select()? If so, how? If not, what are my alternatives here? Here's some output from my program. My alarm function simply outputs "Tick!" whenever it's called to make it easy to tell when stuff is happening. This is the output (including errors) after allowing it to tick 4 times (there were no actual attempts at connecting to the server despite what it says): [05-28-10 @ 20:01:05] Chat server started on 192.168.1.28 port 4050 [05-28-10 @ 20:01:05] Loaded 2 users from file PHP Notice: Undefined offset: 0 in /home/danny/projects/PHPChatServ/ChatServ.php on line 112 PHP Warning: socket_select(): unable to select [4]: Interrupted system call in /home/danny/projects/PHPChatServ/ChatServ.php on line 116 [05-28-10 @ 20:01:15] Tick! PHP Warning: socket_accept(): unable to accept incoming connection [4]: Interrupted system call in /home/danny/projects/PHPChatServ/ChatServ.php on line 126 [05-28-10 @ 20:01:25] Tick! PHP Warning: socket_getpeername() expects parameter 1 to be resource, boolean given in /home/danny/projects/PHPChatServ/ChatServ.php on line 129 [05-28-10 @ 20:01:25] Accepting socket connection from PHP Notice: Undefined offset: 1 in /home/danny/projects/PHPChatServ/ChatServ.php on line 112 PHP Warning: socket_select(): unable to select [4]: Interrupted system call in /home/danny/projects/PHPChatServ/ChatServ.php on line 116 [05-28-10 @ 20:01:35] Tick! PHP Warning: socket_accept(): unable to accept incoming connection [4]: Interrupted system call in /home/danny/projects/PHPChatServ/ChatServ.php on line 126 [05-28-10 @ 20:01:45] Tick! PHP Warning: socket_getpeername() expects parameter 1 to be resource, boolean given in /home/danny/projects/PHPChatServ/ChatServ.php on line 129 [05-28-10 @ 20:01:45] Accepting socket connection from PHP Notice: Undefined offset: 2 in /home/danny/projects/PHPChatServ/ChatServ.php on line 112

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  • Run bat file in Java and wait 2

    - by Savvas Dalkitsis
    This is a followup question to my other question : http://stackoverflow.com/questions/2434125/run-bat-file-in-java-and-wait The reason i am posting this as a separate question is that the one i already asked was answered correctly. From some research i did my problem is unique to my case so i decided to create a new question. Please go read that question before continuing with this one as they are closely related. Running the proposed code blocks the program at the waitFor invocation. After some research i found that the waitFor method blocks if your process has output that needs to be proccessed so you should first empty the output stream and the error stream. I did those things but my method still blocks. I then found a suggestion to simply loop while waiting the exitValue method to return the exit value of the process and handle the exception thrown if it is not, pausing for a brief moment as well so as not to consume all the CPU. I did this: import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; public class Test { public static void main(String[] args) { try { Process p = Runtime.getRuntime().exec( "cmd /k start SQLScriptsToRun.bat" + " -UuserName -Ppassword" + " projectName"); final BufferedReader input = new BufferedReader(new InputStreamReader(p.getInputStream())); final BufferedReader error = new BufferedReader(new InputStreamReader(p.getErrorStream())); new Thread(new Runnable() { @Override public void run() { try { while (input.readLine()!=null) {} } catch (IOException e) { e.printStackTrace(); } } }).start(); new Thread(new Runnable() { @Override public void run() { try { while (error.readLine()!=null) {} } catch (IOException e) { e.printStackTrace(); } } }).start(); int i = 0; boolean finished = false; while (!finished) { try { i = p.exitValue(); finished = true; } catch (IllegalThreadStateException e) { e.printStackTrace(); try { Thread.sleep(500); } catch (InterruptedException e1) { e1.printStackTrace(); } } } System.out.println(i); } catch (IOException e) { e.printStackTrace(); } } } but my process will not end! I keep getting this error: java.lang.IllegalThreadStateException: process has not exited Any ideas as to why my process will not exit? Or do you have any libraries to suggest that handle executing batch files properly and wait until the execution is finished?

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  • jquery question - addclass to element depending on active image in rotating banner

    - by whitman6732
    I have a banner that rotates a series of three images. The active one has a display:block, while the inactive have display:none. I'm trying to match the class for the active image with an tag so that I can add an "active" class to the a tag. Having some trouble writing that function. It's adding all of the classes for each of the img elements, regardless of whether they're being displayed or not... The html markup looks like this: <div id="banner-area"> <div class="clearfix" id="promo-boxes-nav"> <ul id="banner-tabs"> <li> <ul id="page-tabs"> <li><a class="t39" href="#">1</a></li> <li><a class="t42" href="#">2</a></li> <li><a class="t49" href="#">3</a></li> </ul> </li> <li class="last">&nbsp;</li> </ul> </div> <div id="banner-content"> <img class="t39" src="http://localhost:8888/1.png" style="position: absolute; top: 0px; left: 0px; display: none; opacity: 0;"> <img class="t42" src="http://localhost:8888/2.png" style="position: absolute; top: 0px; left: 0px; display: block; opacity: 1;"> <img class="t49" src="http://localhost:8888/3.png" style="position: absolute; top: 0px; left: 0px; display: none;opacity: 0;"> </div> </div> The function in its current form looks like this: $j(document).ready(function() { $j('#banner-content') .cycle({ fx: 'fade', speed: 300, timeout: 3000, next: '.t1', pause: 1 }); if($j('#page-tabs a').attr('class')) { $j('#banner-content img').each(function() { if($j(this).attr('display','block')) { var bcClass = $j(this).attr('class'); } $j('#page-tabs li a').each(function() { if($j('#page-tabs li a').hasClass(bcClass)) { $j(this).addClass(bcClass); } }); }); } })

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  • sql: Group by x,y,z; return grouped by x,y with lowest f(z)

    - by Sai Emrys
    This is for http://cssfingerprint.com I collect timing stats about how fast the different methods I use perform on different browsers, etc., so that I can optimize the scraping speed. Separately, I have a report about what each method returns for a handful of URLs with known-correct values, so that I can tell which methods are bogus on which browsers. (Each is different, alas.) The related tables look like this: CREATE TABLE `browser_tests` ( `id` int(11) NOT NULL AUTO_INCREMENT, `bogus` tinyint(1) DEFAULT NULL, `result` tinyint(1) DEFAULT NULL, `method` varchar(255) DEFAULT NULL, `url` varchar(255) DEFAULT NULL, `os` varchar(255) DEFAULT NULL, `browser` varchar(255) DEFAULT NULL, `version` varchar(255) DEFAULT NULL, `created_at` datetime DEFAULT NULL, `updated_at` datetime DEFAULT NULL, `user_agent` varchar(255) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB AUTO_INCREMENT=33784 DEFAULT CHARSET=latin1 CREATE TABLE `method_timings` ( `id` int(11) NOT NULL AUTO_INCREMENT, `method` varchar(255) DEFAULT NULL, `batch_size` int(11) DEFAULT NULL, `timing` int(11) DEFAULT NULL, `os` varchar(255) DEFAULT NULL, `browser` varchar(255) DEFAULT NULL, `version` varchar(255) DEFAULT NULL, `user_agent` varchar(255) DEFAULT NULL, `created_at` datetime DEFAULT NULL, `updated_at` datetime DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB AUTO_INCREMENT=28849 DEFAULT CHARSET=latin1 (user_agent is broken down pre-insert into browser, version, and os from a small list of recognized values using regex; I keep the original user-agent string just in case.) I have a query like this that tells me the average timing for every non-bogus browser / version / method tuple: select c, avg(bogus) as bog, timing, method, browser, version from browser_tests as b inner join ( select count(*) as c, round(avg(timing)) as timing, method, browser, version from method_timings group by browser, version, method having c > 10 order by browser, version, timing ) as t using (browser, version, method) group by browser, version, method having bog < 1 order by browser, version, timing; Which returns something like: c bog tim method browser version 88 0.8333 184 reuse_insert Chrome 4.0.249.89 18 0.0000 238 mass_insert_width Chrome 4.0.249.89 70 0.0400 246 mass_insert Chrome 4.0.249.89 70 0.0400 327 mass_noinsert Chrome 4.0.249.89 88 0.0556 367 reuse_reinsert Chrome 4.0.249.89 88 0.0556 383 jquery Chrome 4.0.249.89 88 0.0556 863 full_reinsert Chrome 4.0.249.89 187 0.0000 105 jquery Chrome 5.0.307.11 187 0.8806 109 reuse_insert Chrome 5.0.307.11 123 0.0000 110 mass_insert_width Chrome 5.0.307.11 176 0.0000 231 mass_noinsert Chrome 5.0.307.11 176 0.0000 237 mass_insert Chrome 5.0.307.11 187 0.0000 314 reuse_reinsert Chrome 5.0.307.11 187 0.0000 372 full_reinsert Chrome 5.0.307.11 12 0.7500 82 reuse_insert Chrome 5.0.335.0 12 0.2500 102 jquery Chrome 5.0.335.0 [...] I want to modify this query to return only the browser/version/method with the lowest timing - i.e. something like: 88 0.8333 184 reuse_insert Chrome 4.0.249.89 187 0.0000 105 jquery Chrome 5.0.307.11 12 0.7500 82 reuse_insert Chrome 5.0.335.0 [...] How can I do this, while still returning the method that goes with that lowest timing? I could filter it app-side, but I'd rather do this in mysql since it'd work better with my caching.

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  • How to do role-based access control for a franchise business?

    - by FreshCode
    I'm building the 2nd iteration of a web-based CRM+CMS for a franchise service business in ASP.NET MVC 2. I need to control access to each franchise's services based on the roles a user is assigned for that franchise. 4 examples: Receptionist should be able to book service jobs in for her "Atlantic Seaboard" franchise, but not do any reporting. Technician should be able to alter service jobs, but not modify invoices. Managers should be able to apply discount to invoices for jobs within their stores. Owner should be able to pull reports for any franchises he owns. Where should franchise-level access control fit in between the Data - Services - Web layer? If it belongs in my Controllers, how should I best implement it? Partial Schema Roles class int ID { get; set; } // primary key for Role string Name { get; set; } Partial Franchises class short ID { get; set; } // primary key for Franchise string Slug { get; set; } // unique key for URL access, eg /{franchise}/{job} string Name { get; set; } UserRoles mapping short FranchiseID; // related to franchises table Guid UserID; // related to Users table int RoleID; // related to Roles table DateTime ValidFrom; DateTime ValidUntil; Background I built the previous CRM in classic ASP and it runs the business well, but it's time for an upgrade to speed up workflow and leave less room for error. For the sake of proper testing and better separation between data and presentation, I decided to implement the repository pattern as seen in Rob Conery's MVC Storefront series. Controller Implementation Access Control with [Authorize] attribute If there was just one franchise involved, I could simply limit access to a controller action like so: [Authorize(Roles="Receptionist, Technician, Manager, Owner")] public ActionResult CreateJob(Job job) { ... } And since franchises don't just pop up over night, perhaps this is a strong case to use the new Areas feature in ASP.NET MVC 2? Or would this lead to duplicate Views? Controllers, URL Routing & Areas Assuming Areas aren't used, what would be the best way to determine which franchise's data is being accessed? I thought of this: {franchise}/{controller}/{action}/{id} or is it better to determine a job's franchise in a Details(...) action and limit a user's action with [Authorize]: {job}/{id}/{action}/{subaction} {invoice}/{id}/{action}/{subaction} which makes more sense if any user could potentially have access to more than one franchise without cluttering the URL with a {franchise} parameter. Any input is appreciated.

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  • Unable to execute a function using reflection

    - by Steven
    hi, i am developing a eclipse plugin . In this plugin i am using reflection to execute a function in a class present in another project which is a hibernate project.Whenever the invoke is used i.e mymethod.invoke(myobj); it is giving this exception java.lang.reflect.InvocationTargetException at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37) at java.lang.reflect.Method.invoke(Method.java:599) at packagesearch.DummyExecution.execution(DummyExecution.java:154) at packagesearch.HelloWorldAction.run(HelloWorldAction.java:48) at org.eclipse.ui.internal.PluginAction.runWithEvent(PluginAction.java:251) at org.eclipse.ui.internal.WWinPluginAction.runWithEvent(WWinPluginAction.java:229) at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:583) at org.eclipse.jface.action.ActionContributionItem.access$2(ActionContributionItem.java:500) at org.eclipse.jface.action.ActionContributionItem$6.handleEvent(ActionContributionItem.java:452) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1003) at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3823) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3422) at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2384) at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2348) at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2200) at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:495) at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:288) at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:490) at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149) at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:113) at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:193) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:386) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37) at java.lang.reflect.Method.invoke(Method.java:599) at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:549) at org.eclipse.equinox.launcher.Main.basicRun(Main.java:504) at org.eclipse.equinox.launcher.Main.run(Main.java:1236) at org.eclipse.equinox.launcher.Main.main(Main.java:1212) Caused by: java.lang.NoClassDefFoundError: org.dom4j.DocumentException at java.lang.J9VMInternals.verifyImpl(Native Method) at java.lang.J9VMInternals.verify(J9VMInternals.java:72) at java.lang.J9VMInternals.initialize(J9VMInternals.java:134) at test.Example.demo1(Example.java:38) ... 36 more Caused by: java.lang.ClassNotFoundException: org.dom4j.DocumentException at java.net.URLClassLoader.findClass(URLClassLoader.java:419) at java.lang.ClassLoader.loadClass(ClassLoader.java:643) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:345) at java.lang.ClassLoader.loadClass(ClassLoader.java:609) ... 40 more what is the exact problem . i have used loader to load the class.Help

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  • SQL Server to PostgreSQL - Migration and design concerns

    - by youwhut
    Currently migrating from SQL Server to PostgreSQL and attempting to improve a couple of key areas on the way: I have an Articles table: CREATE TABLE [dbo].[Articles]( [server_ref] [int] NOT NULL, [article_ref] [int] NOT NULL, [article_title] [varchar](400) NOT NULL, [category_ref] [int] NOT NULL, [size] [bigint] NOT NULL ) Data (comma delimited text files) is dumped on the import server by ~500 (out of ~1000) servers on a daily basis. Importing: Indexes are disabled on the Articles table. For each dumped text file Data is BULK copied to a temporary table. Temporary table is updated. Old data for the server is dropped from the Articles table. Temporary table data is copied to Articles table. Temporary table dropped. Once this process is complete for all servers the indexes are built and the new database is copied to a web server. I am reasonably happy with this process but there is always room for improvement as I strive for a real-time (haha!) system. Is what I am doing correct? The Articles table contains ~500 million records and is expected to grow. Searching across this table is okay but could be better. i.e. SELECT * FROM Articles WHERE server_ref=33 AND article_title LIKE '%criteria%' has been satisfactory but I want to improve the speed of searching. Obviously the "LIKE" is my problem here. Suggestions? SELECT * FROM Articles WHERE article_title LIKE '%criteria%' is horrendous. Partitioning is a feature of SQL Server Enterprise but $$$ which is one of the many exciting prospects of PostgreSQL. What performance hit will be incurred for the import process (drop data, insert data) and building indexes? Will the database grow by a huge amount? The database currently stands at 200 GB and will grow. Copying this across the network is not ideal but it works. I am putting thought into changing the hardware structure of the system. The thought process of having an import server and a web server is so that the import server can do the dirty work (WITHOUT indexes) while the web server (WITH indexes) can present reports. Maybe reducing the system down to one server would work to skip the copying across the network stage. This one server would have two versions of the database: one with the indexes for delivering reports and the other without for importing new data. The databases would swap daily. Thoughts? This is a fantastic system, and believe it or not there is some method to my madness by giving it a big shake up. UPDATE: I am not looking for help with relational databases, but hoping to bounce ideas around with data warehouse experts.

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  • gcc precompiled headers weird behaviour with -c option

    - by pachanga
    Folks, I'm using gcc-4.4.1 on Linux and before trying precompiled headers in a really large project I decided to test them on simple program. They "kinda work" but I'm not happy with results and I'm sure there is something wrong about my setup. First of all, I wrote a simple program(main.cpp) to test if they work at all: #include <boost/bind.hpp> #include <boost/function.hpp> #include <boost/type_traits.hpp> int main() { return 0; } Then I created the precompiled headers file pre.h(in the same directory) as follows: #include <boost/bind.hpp> #include <boost/function.hpp> #include <boost/type_traits.hpp> ...and compiled it: $ g++ -I. pre.h (pre.h.gch was created) After that I measured compile time with and without precompiled headers: with pch $ time g++ -I. -include pre.h main.cpp real 0m0.128s user 0m0.088s sys 0m0.048s without pch $ time g++ -I. main.cpp real 0m0.838s user 0m0.784s sys 0m0.056s So far so good! Almost 7 times faster, that's impressive! Now let's try something more realistic. All my sources are built with -c option and for some reason I can't make pch play nicely with it. You can reproduce this with the following steps below... I created the test module foo.cpp as follows: #include <boost/bind.hpp> #include <boost/function.hpp> #include <boost/type_traits.hpp> int whatever() { return 0; } Here are the timings of my attempts to build the module foo.cpp with and without pch: with pch $ time g++ -I. -include pre.h -c foo.cpp real 0m0.357s user 0m0.348s sys 0m0.012s without pch $ time g++ -I. -c foo.cpp real 0m0.330s user 0m0.292s sys 0m0.044s That's quite strange, looks like there is no speed up at all!(I ran timings for several times). It turned out precompiled headers were not used at all in this case, I checked it with -H option(output of "g++ -I. -include pre.h -c foo.cpp -H" didn't list pre.h.gch at all). What am I doing wrong?

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  • Most efficient algorithm for merging sorted IEnumerable<T>

    - by franck
    Hello, I have several huge sorted enumerable sequences that I want to merge. Theses lists are manipulated as IEnumerable but are already sorted. Since input lists are sorted, it should be possible to merge them in one trip, without re-sorting anything. I would like to keep the defered execution behavior. I tried to write a naive algorithm which do that (see below). However, it looks pretty ugly and I'm sure it can be optimized. It may exist a more academical algorithm... IEnumerable<T> MergeOrderedLists<T, TOrder>(IEnumerable<IEnumerable<T>> orderedlists, Func<T, TOrder> orderBy) { var enumerators = orderedlists.ToDictionary(l => l.GetEnumerator(), l => default(T)); IEnumerator<T> tag = null; var firstRun = true; while (true) { var toRemove = new List<IEnumerator<T>>(); var toAdd = new List<KeyValuePair<IEnumerator<T>, T>>(); foreach (var pair in enumerators.Where(pair => firstRun || tag == pair.Key)) { if (pair.Key.MoveNext()) toAdd.Add(pair); else toRemove.Add(pair.Key); } foreach (var enumerator in toRemove) enumerators.Remove(enumerator); foreach (var pair in toAdd) enumerators[pair.Key] = pair.Key.Current; if (enumerators.Count == 0) yield break; var min = enumerators.OrderBy(t => orderBy(t.Value)).FirstOrDefault(); tag = min.Key; yield return min.Value; firstRun = false; } } The method can be used like that: // Person lists are already sorted by age MergeOrderedLists(orderedList, p => p.Age); assuming the following Person class exists somewhere: public class Person { public int Age { get; set; } } Duplicates should be conserved, we don't care about their order in the new sequence. Do you see any obvious optimization I could use?

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  • Unable to execute a function usnig reflection

    - by Steven
    hi, i am developing a eclipse plugin . In this plugin i am using reflection to execute a function in a class present in another project which is a hibernate project.Whenever the invoke is used i.e mymethod.invoke(myobj); it is giving this exception java.lang.reflect.InvocationTargetException at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37) at java.lang.reflect.Method.invoke(Method.java:599) at packagesearch.DummyExecution.execution(DummyExecution.java:154) at packagesearch.HelloWorldAction.run(HelloWorldAction.java:48) at org.eclipse.ui.internal.PluginAction.runWithEvent(PluginAction.java:251) at org.eclipse.ui.internal.WWinPluginAction.runWithEvent(WWinPluginAction.java:229) at org.eclipse.jface.action.ActionContributionItem.handleWidgetSelection(ActionContributionItem.java:583) at org.eclipse.jface.action.ActionContributionItem.access$2(ActionContributionItem.java:500) at org.eclipse.jface.action.ActionContributionItem$6.handleEvent(ActionContributionItem.java:452) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1003) at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3823) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3422) at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2384) at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2348) at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2200) at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:495) at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:288) at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:490) at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149) at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:113) at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:193) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:386) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:37) at java.lang.reflect.Method.invoke(Method.java:599) at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:549) at org.eclipse.equinox.launcher.Main.basicRun(Main.java:504) at org.eclipse.equinox.launcher.Main.run(Main.java:1236) at org.eclipse.equinox.launcher.Main.main(Main.java:1212) Caused by: java.lang.NoClassDefFoundError: org.dom4j.DocumentException at java.lang.J9VMInternals.verifyImpl(Native Method) at java.lang.J9VMInternals.verify(J9VMInternals.java:72) at java.lang.J9VMInternals.initialize(J9VMInternals.java:134) at test.Example.demo1(Example.java:38) ... 36 more Caused by: java.lang.ClassNotFoundException: org.dom4j.DocumentException at java.net.URLClassLoader.findClass(URLClassLoader.java:419) at java.lang.ClassLoader.loadClass(ClassLoader.java:643) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:345) at java.lang.ClassLoader.loadClass(ClassLoader.java:609) ... 40 more what is the exact problem . i have used loader to load the class.Help

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  • Superfish: How to keep sub menu open after it has been clicked

    - by Roland
    I'm having the following scenario. I have a menu and if one hovers over the menu a sub menu appears and if mouse moves out the sub menu disappears, now I want the following if I click on the on a item in the sub menu, I want the sub-menu to remain open, when the new page has been loaded. I'm using superfish Jquery plugin for this. Is this possible and if how. my code in html <div id="nav"> <div id="nav2"> <ul class="sf-menu sf-navbar "> <li> <a title="HOME" class="sf-with-ul " href="/index.php?r=site/index&amp;sid=1">HOME</a> </li> </ul> <ul class="sf-menu sf-navbar"> <li> <a href="?sid=2" id="gallery" class="sf-with-ul selected_main">GALLERY</a> <ul class="subs" id="sub1"><li class="arrow"><img src="images/arrow.gif" /></li><li><a title="Kitchens" href="/index.php?r=images/sddsd&amp;id=1">Kitchens</a></li><li><a title="Vanities" href="/index.php?r=images/sddsd&amp;id=2">Vanities</a></li></ul> </li> </ul> <ul class="sf-menu sf-navbar "> <li> <a href="?sid=3" class="sf-with-ul " >ACCESSORIES</a> <ul class="subs" id=""><li class="arrow"><img src="images/arrow.gif" /></li><li><a title="Door Handles" href="/index.php?r=images/sddsd&amp;id=2">Door Handles</a></li><li><a title="Spanners" href="/index.php?r=images/sddsd&amp;id=1">Spanners</a></li></ul> </li> </ul> <ul class="sf-menu sf-navbar "> <li> <a title="CONTACT US" class="sf-with-ul " href="/index.php?r=site/contact&amp;sid=4">CONTACT US</a> </li> </ul> </div> </div> and then the superfish code $(function(){ $("ul.sf-menu").superfish({ delay: 0, speed: 'fast', autoArrows: false, dropShadows: false }); }); I've also noticed that the following css code is used to display the item left: 0; top: 2.5em; z-index: 99;

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  • Managing a difficult manager

    - by griegs
    I have a situation here at work. We are redeveloping our basic architecture across the entire company. Currently we have the following hierarchy; SQL Database <= Stored Procs not allowed. nHibernate Classes to convert nHibernate into our own objects Web Service <= for all external and [internal] calls. Class to take objects from Web Service and back into our own objects and then… Normal nTier application architecture such as Data Transformation Layer, Business layer etc. Within the database, when we are writing a hierarchy of objects to the database, say for example; Order Person Details Address Product Other We need to serialise the object and save it, in its entirety, to an image field in a table. No attempt has been made to store the objects in their own tables so that we can do useful stuff like report on it. This is an architecture that was implemented [way] before I started and as you can probably appreciate, is a complete nightmare not to mention slow as a wet weekend. We’re not even allowed to have stored procs within SQL server because in my boss’s last job they had a hundred or so and he had a problem identifying them all so therefore all stored procs are the devil. Now the same person that developed the above architecture has developed the new one. It came as no surprise that he’s essentially used the same framework only now it’s using DotNet 3.5 with interfaces and generics. We still have to go through web services, still need to serialise (everything), still not allowed to use stored procs etc. In fact, we’re only barely able to bang two rocks together here. He says to us that the framework is open for discussion but when you discuss it, unless you approve of his design, you are told flatly “No”. He simply won’t listen to any other suggestions. Even when you show him demo applications of his proposed architecture v’s yours and he can see the speed difference, he still won’t take that on board. So I guess my question is, and I know others have experienced the same things out there, how do I get through to someone like this? How do you convince someone to ditch Web Services for internal calls and applications? How do you demonstrate, and make it stick, that stored procs are a better way to go than ad-hoc sql statements? This is killing me. I don’t want to repeat the mistakes of the past and I certainly don’t want to write code that I know is going to be slow and cumbersome. Help!

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  • How to configure maximum number of transport channels in WCF using basicHttpBinding?

    - by Hemant
    Consider following code which is essentially a WCF host: [ServiceContract (Namespace = "http://www.mightycalc.com")] interface ICalculator { [OperationContract] int Add (int aNum1, int aNum2); } [ServiceBehavior (InstanceContextMode = InstanceContextMode.PerCall)] class Calculator: ICalculator { public int Add (int aNum1, int aNum2) { Thread.Sleep (2000); //Simulate a lengthy operation return aNum1 + aNum2; } } class Program { static void Main (string[] args) { try { using (var serviceHost = new ServiceHost (typeof (Calculator))) { var httpBinding = new BasicHttpBinding (BasicHttpSecurityMode.None); serviceHost.AddServiceEndpoint (typeof (ICalculator), httpBinding, "http://172.16.9.191:2221/calc"); serviceHost.Open (); Console.WriteLine ("Service is running. ENJOY!!!"); Console.WriteLine ("Type 'stop' and hit enter to stop the service."); Console.ReadLine (); if (serviceHost.State == CommunicationState.Opened) serviceHost.Close (); } } catch (Exception e) { Console.WriteLine (e); Console.ReadLine (); } } } Also the WCF client program is: class Program { static int COUNT = 0; static Timer timer = null; static void Main (string[] args) { var threads = new Thread[10]; for (int i = 0; i < threads.Length; i++) { threads[i] = new Thread (Calculate); threads[i].Start (null); } timer = new Timer (o => Console.WriteLine ("Count: {0}", COUNT), null, 1000, 1000); Console.ReadLine (); timer.Dispose (); } static void Calculate (object state) { var c = new CalculatorClient ("BasicHttpBinding_ICalculator"); c.Open (); while (true) { try { var sum = c.Add (2, 3); Interlocked.Increment (ref COUNT); } catch (Exception ex) { Console.WriteLine ("Error on thread {0}: {1}", Thread.CurrentThread.Name, ex.GetType ()); break; } } c.Close (); } } Basically, I am creating 10 proxy clients and then repeatedly calling Add service method. Now if I run both applications and observe opened TCP connections using netstat, I find that: If both client and server are running on same machine, number of tcp connections are equal to number of proxy objects. It means all requests are being served in parallel. Which is good. If I run server on a separate machine, I observed that maximum 2 TCP connections are opened regardless of the number of proxy objects I create. Only 2 requests run in parallel. It hurts the processing speed badly. If I switch to net.tcp binding, everything works fine (a separate TCP connection for each proxy object even if they are running on different machines). I am very confused and unable to make the basicHttpBinding use more TCP connections. I know it is a long question, but please help!

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  • SQL server timeout 2000 from C# .NET

    - by Johnny Egeland
    I have run into a strange problem using SQL Server 2000 and two linked server. For two years now our solution has run without a hitch, but suddenly yesterday a query synchronizing data from one of the databases to the other started timing out. I connect to a server in the production network, which is linked to a server containing orders I need data from. The query contains a few joins, but basically this summarizes what is done: INSERT INTO ProductionDataCache (column1, column2, ...) SELECT tab1.column1, tab1.column2, tab2.column1, tab3.column1 ... FROM linkedserver.database.dbo.Table1 AS tab1 JOIN linkedserver.database.dbo.Table2 AS tab2 ON (...) JOIN linkedserver.database.dbo.Tabl32 AS tab3 ON (...) ... WHERE tab1.productionOrderId = @id ORDER BY ... Obviously my first attempt to fix the problem was to increase the timeout limit from the original 5 minutes. But when I arrived at 30 minutes and still got a timeout, I started to suspect something else was going on. A query just does not go from executing in less than 5 minutes to over 30 minutes over night. I outputted the SQL query (which was originally in the C# code) to my logs, and decided to execute the query in the Query Analyzer directly on the database server. To my big surprise, the query executed correctly in less than 10 seconds. So I isolated the SQL execution in a simple test program, and observed the same query time out both on the server originally running this solution AND when running it locally on the database server. Also I have tried to create a Stored Procedure and execute this from the program, but this also times out. Running it in Query Analyzer works fine in less than a few seconds. It seems that the problem only occurs when I execute this query from the C# program. Has anyone seen such behavior before, and found a solution for it? UPDATE: I have now used SQL Profiler on the server. The obvious difference is that when executing the query from the .NET program, it shows up in the log as "exec sp_executesql N'INSERT INTO ...'", but when executing from Query Analyzer it occurs as a normal query in the log. Further I tried to connect the SQL Query Analyzer using the same SQL user as the program, and this triggered the problem in Query Analyzer as well. So it seems the problem only occurs when connecting via TCP/IP using a sql user.

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  • WCF XmlSerializer assembly not speeding up first request

    - by Matt Dearing
    I am generating proxy classes to a clients java webservice wsdls and xsd files with svcutil. The first call made to each service proxy class takes a very long time. I was hoping to speed this up by generating the XmlSerializers assembly myself (based on the article How to: Improve the Startup Time of WCF Client Applications using the XmlSerializer), but when I do the first call to each service still takes the same amount of time. Here are the steps I am following: //generate strong name key file sn -k Blah.snk //generate the proxy class file svcutil blah.wsdl blah2.wsdl blah3.wsdl ... base.xsd blah.xsd ... /UseSerializerForFaults /ser:XmlSerializer /n:*,SomeNamespace /out:Blah.cs //compile the class into an assembly signing it with the strong name key file csc /target:library /keyfile:Blah.snk /out:Blah.dll Blah.cs //generate the XmlSerializer code this will give us Blah.XmlSerializers.dll.cs svcutil /t:xmlSerializer Blah.dll //compile the xmlserializer code into its own dll using the same key to sign it and referencing the original dll csc /target:library /keyfile:Blah.snk /out:Blah.XmlSerializers.dll Blah.XmlSerializers.dll.cs /r:Blah.dll I then create a standard Console application that references both Blah.dll and Blah.XmlSerializers.dll. I will then try something like: //BlahProxy is one of the generated service proxy classes BlahProxy p = new BlahProxy(); //this call takes 30ish seconds p.SomeMethod(); BlahProxy p2 = new BlahProxy(); //this call takes < 1 second p2.SomeMethod(); //BlahProx2y is one of the generated service proxy classes BlahProxy2 p3 = new BlahProxy2(); //this call takes 30ish seconds p3.SomeMethod(); BlahProxy2 p4 = new BlahProxy2(); //this call takes < 1 second p4.SomeMethod(); I know that the problem is not server side because I don't see the request made in Fiddler until around 29 seconds. Subsequent calls to each service take < 1 second, so thats why I was hoping the main slow down was the .net runtime generating the xmlserializer code itself, compiling it and loading the assembly. I figured this would be the reason the first call to each service is slow and the rest are fast. Unfortunatley, me generating the code myself is not speeding anything up. Does anyone see what I am doing wrong?

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  • Panning weirdness on an UserControl

    - by Matías
    Hello, I'm trying to build my own "PictureBox like" control adding some functionalities. For example, I want to be able to pan over a big image by simply clicking and dragging with the mouse. The problem seems to be on my OnMouseMove method. If I use the following code I get the drag speed and precision I want, but of course, when I release the mouse button and try to drag again the image is restored to its original position. using System.Drawing; using System.Windows.Forms; namespace Testing { public partial class ScrollablePictureBox : UserControl { private Image image; private bool centerImage; public Image Image { get { return image; } set { image = value; Invalidate(); } } public bool CenterImage { get { return centerImage; } set { centerImage = value; Invalidate(); } } public ScrollablePictureBox() { InitializeComponent(); SetStyle(ControlStyles.AllPaintingInWmPaint | ControlStyles.OptimizedDoubleBuffer, true); Image = null; AutoScroll = true; AutoScrollMinSize = new Size(0, 0); } private Point clickPosition; private Point scrollPosition; protected override void OnMouseDown(MouseEventArgs e) { base.OnMouseDown(e); clickPosition.X = e.X; clickPosition.Y = e.Y; } protected override void OnMouseMove(MouseEventArgs e) { base.OnMouseMove(e); if (e.Button == MouseButtons.Left) { scrollPosition.X = clickPosition.X - e.X; scrollPosition.Y = clickPosition.Y - e.Y; AutoScrollPosition = scrollPosition; } } protected override void OnPaint(PaintEventArgs e) { base.OnPaint(e); e.Graphics.FillRectangle(new Pen(BackColor).Brush, 0, 0, e.ClipRectangle.Width, e.ClipRectangle.Height); if (Image == null) return; int centeredX = AutoScrollPosition.X; int centeredY = AutoScrollPosition.Y; if (CenterImage) { //Something not relevant } AutoScrollMinSize = new Size(Image.Width, Image.Height); e.Graphics.DrawImage(Image, new RectangleF(centeredX, centeredY, Image.Width, Image.Height)); } } } But if I modify my OnMouseMove method to look like this: protected override void OnMouseMove(MouseEventArgs e) { base.OnMouseMove(e); if (e.Button == MouseButtons.Left) { scrollPosition.X += clickPosition.X - e.X; scrollPosition.Y += clickPosition.Y - e.Y; AutoScrollPosition = scrollPosition; } } ... you will see that the dragging is not smooth as before, and sometimes behaves weird (like with lag or something). What am I doing wrong? I've also tried removing all "base" calls on a desperate movement to solve this issue, haha, but again, it didn't work. Thanks for your time.

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  • NoHostAvailableException With Cassandra & DataStax Java Driver If Large ResultSet

    - by hughj
    The setup: 2-node Cassandra 1.2.6 cluster replicas=2 very large CQL3 table with no secondary index Rowkey is a UUID.randomUUID().toString() read consistency set to ONE Using DataStax java driver 1.0 The request: Attempting to do a table scan by "SELECT some-col from schema.table LIMIT nnn;" The fail: Once I go beyond a certain nnn LIMIT, I start to get NoHostAvailableExceptions from the driver. It reads like this: com.datastax.driver.core.exceptions.NoHostAvailableException: All host(s) tried for query failed (tried: /10.181.13.239 ([/10.181.13.239] Unexpected exception triggered)) at com.datastax.driver.core.exceptions.NoHostAvailableException.copy(NoHostAvailableException.java:64) at com.datastax.driver.core.ResultSetFuture.extractCauseFromExecutionException(ResultSetFuture.java:214) at com.datastax.driver.core.ResultSetFuture.getUninterruptibly(ResultSetFuture.java:169) at com.jpmc.es.rtm.storage.impl.EventExtract.main(EventExtract.java:36) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:601) at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120) Caused by: com.datastax.driver.core.exceptions.NoHostAvailableException: All host(s) tried for query failed (tried: /10.181.13.239 ([/10.181.13.239] Unexpected exception triggered)) at com.datastax.driver.core.RequestHandler.sendRequest(RequestHandler.java:98) at com.datastax.driver.core.RequestHandler$1.run(RequestHandler.java:165) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603) Given: This is probably not the most enlightened thing to do to a large table with millions of rows, but this is how I learn what not to do, so I would really appreciate someone who could volunteer how this kind of error can be debugged. For example, when this happens, there are no indications that the nodes in the cluster ever had an issue with the request (there is nothing in the logs on either node that indicate any timeout or failure). Also, I enabled the trace on the driver, which gives you some nice autotrace (ala Oracle) info as long as the query succeeds. But in this case, the driver blows a NoHostAvailableException and no ExecutionInfo is available, so tracing has not provided any benefit in this case. I also find it interesting that this does not seem to be recorded as a timeout (my JMX consoles tell me no timeouts have occurred). So, I am left not understanding WHERE the failure is actually occurring. I am left with the idea that it is the driver that is having a problem, but I don't know how to debug it (and I would really like to). I have read several posts from folks that state that query'g for resultSets 10000 rows is probably not a good idea, and I am willing to accept this, but I would like to understand what is causing the exception and where the exception is happening. FWIW, I also tried bumping the timeout properties in the cassandra.yaml, but this made no difference whatsoever. I welcome any suggestions, anecdotes, insults, or monetary contributions for my registration in the house of moron-developers. Regards!!

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  • how to store xml structure in a persistence layer?

    - by fayer
    i wonder how i could store a xml structure in a persistence layer. cause the relational data looks like: <entity id="1000070"> <name>apple</name> <entities> <entity id="7002870"> <name>mac</name> <entities> <entity id="7002907"> <name>leopard</name> <entities> <entity id="7024080"> <name>safari</name> </entity> <entity id="7024701"> <name>finder</name> </entity> </entities> </entity> </entities> </entity> <entity id="7024080"> <name>iphone</name> <entities> <entity id="7024080"> <name>3g</name> </entity> <entity id="7024701"> <name>3gs</name> </entity> </entities> </entity> <entity id="7024080"> <name>ipad</name> </entity> </entities> </entity> as you can see, it has no static structure but a dynamical one. mac got 2 descendant levels while iphone got 1 and ipad got 0. i wonder how i could store this data the best way? what are my options. cause it seems impossible to store it in a mysql database due to this dynamical structure. is the only way to store it as a xml file then? is the speed of getting information (xpath/xquery/simplexml) from a xml file worse or greater than from mysql? what are the pros and cons? do i have other options? is storing information in xml files, suited for a lot of users accessing it at the same time? would be great with feedbacks!! thanks!

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  • GOTO still considered harmful?

    - by Kyle Cronin
    Everyone is aware of Dijkstra's Letters to the editor: go to statement considered harmful (also here .html transcript and here .pdf) and there has been a formidable push since that time to eschew the goto statement whenever possible. While it's possible to use goto to produce unmaintainable, sprawling code, it nevertheless remains in modern programming languages. Even the advanced continuation control structure in Scheme can be described as a sophisticated goto. What circumstances warrant the use of goto? When is it best to avoid? As a followup question: C provides a pair of functions, setjmp and longjmp, that provide the ability to goto not just within the current stack frame but within any of the calling frames. Should these be considered as dangerous as goto? More dangerous? Dijkstra himself regretted that title, of which he was not responsible for. At the end of EWD1308 (also here .pdf) he wrote: Finally a short story for the record. In 1968, the Communications of the ACM published a text of mine under the title "The goto statement considered harmful", which in later years would be most frequently referenced, regrettably, however, often by authors who had seen no more of it than its title, which became a cornerstone of my fame by becoming a template: we would see all sorts of articles under the title "X considered harmful" for almost any X, including one titled "Dijkstra considered harmful". But what had happened? I had submitted a paper under the title "A case against the goto statement", which, in order to speed up its publication, the editor had changed into a "letter to the Editor", and in the process he had given it a new title of his own invention! The editor was Niklaus Wirth. A well thought out classic paper about this topic, to be matched to that of Dijkstra, is Structured Programming with go to Statements (also here .pdf), by Donald E. Knuth. Reading both helps to reestablish context and a non-dogmatic understanding of the subject. In this paper, Dijkstra's opinion on this case is reported and is even more strong: Donald E. Knuth: I believe that by presenting such a view I am not in fact disagreeing sharply with Dijkstra's ideas, since he recently wrote the following: "Please don't fall into the trap of believing that I am terribly dogmatical about [the go to statement]. I have the uncomfortable feeling that others are making a religion out of it, as if the conceptual problems of programming could be solved by a single trick, by a simple form of coding discipline!"

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  • Fixed point math in c#?

    - by x4000
    Hi there, I was wondering if anyone here knows of any good resources for fixed point math in c#? I've seen things like this (http://2ddev.72dpiarmy.com/viewtopic.php?id=156) and this (http://stackoverflow.com/questions/79677/whats-the-best-way-to-do-fixed-point-math), and a number of discussions about whether decimal is really fixed point or actually floating point (update: responders have confirmed that it's definitely floating point), but I haven't seen a solid C# library for things like calculating cosine and sine. My needs are simple -- I need the basic operators, plus cosine, sine, arctan2, PI... I think that's about it. Maybe sqrt. I'm programming a 2D RTS game, which I have largely working, but the unit movement when using floating-point math (doubles) has very small inaccuracies over time (10-30 minutes) across multiple machines, leading to desyncs. This is presently only between a 32 bit OS and a 64 bit OS, all the 32 bit machines seem to stay in sync without issue, which is what makes me think this is a floating point issue. I was aware from this as a possible issue from the outset, and so have limited my use of non-integer position math as much as possible, but for smooth diagonal movement at varying speeds I'm calculating the angle between points in radians, then getting the x and y components of movement with sin and cos. That's the main issue. I'm also doing some calculations for line segment intersections, line-circle intersections, circle-rect intersections, etc, that also probably need to move from floating-point to fixed-point to avoid cross-machine issues. If there's something open source in Java or VB or another comparable language, I could probably convert the code for my uses. The main priority for me is accuracy, although I'd like as little speed loss over present performance as possible. This whole fixed point math thing is very new to me, and I'm surprised by how little practical information on it there is on google -- most stuff seems to be either theory or dense C++ header files. Anything you could do to point me in the right direction is much appreciated; if I can get this working, I plan to open-source the math functions I put together so that there will be a resource for other C# programmers out there. UPDATE: I could definitely make a cosine/sine lookup table work for my purposes, but I don't think that would work for arctan2, since I'd need to generate a table with about 64,000x64,000 entries (yikes). If you know any programmatic explanations of efficient ways to calculate things like arctan2, that would be awesome. My math background is all right, but the advanced formulas and traditional math notation are very difficult for me to translate into code.

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  • C++ vs Matlab vs Python as a main language for Computer Vision Research

    - by Hough
    Hi all, Firstly, sorry for a somewhat long question but I think that many people are in the same situation as me and hopefully they can also gain some benefit from this. I'll be starting my PhD very soon which involves the fields of computer vision, pattern recognition and machine learning. Currently, I'm using opencv (2.1) C++ interface and I especially like its powerful Mat class and the overloaded operations available for matrix and image operations and seamless transformations. I've also tried (and implemented many small vision projects) using opencv python interface (new bindings; opencv 2.1) and I really enjoy python's ability to integrate opencv, numpy, scipy and matplotlib. But recently, I went back to opencv C++ interface because I felt that the official python new bindings were not stable enough and no overloaded operations are available for matrices and images, not to mention the lack of machine learning modules and slow speeds in certain operations. I've also used Matlab extensively in the past and although I've used mex files and other means to speed up the program, I just felt that Matlab's performance was inadequate for real-time vision tasks, be it for fast prototyping or not. When the project becomes larger and larger, many tasks have to be re-written in C and compiled into Mex files increasingly and Matlab becomes nothing more than a glue language. Here comes the sub-questions: For carrying out research in these fields (machine learning, vision, pattern recognition), what is your main or ideal programming language for rapid prototyping of ideas and testing algorithms contained in papers? For computer vision research work, can you list down the pros and cons of using the following languages? C++ (with opencv + gsl + svmlib + other libraries) vs Matlab (with all its toolboxes) vs python (with the imcomplete opencv bindings + numpy + scipy + matplotlib). Are there computer vision PhD/postgrad students here who are using only C++ (with all its availabe libraries including opencv) without even needing to resort to Matlab or python? In other words, given the current existing computer vision or machine learning libraries, is C++ alone sufficient for fast prototyping of ideas? If you're currently using Java or C# for your research, can you list down the reasons why they should be used and how they compare to other languages in terms of available libraries? What is the de facto vision/machine learning programming language and its associated libraries used in your research group? Thanks in advance. Edit: As suggested, I've opened the question to both academic and non-academic computer vision/machine learning/pattern recognition researchers and groups.

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  • TVirtualStringTree - resetting non-visual nodes and memory comsumption

    - by Remy Lebeau - TeamB
    I have an app that loads records from a binary log file and displays them in a virtual TListView. There are potentially millions of records in a file, and the display can be filtered by the user, so I do not load all of the records in memory at one time, and the ListView item indexes are not a 1-to-1 relation with the file record offsets (List item 1 may be file record 100, for instance). I use the ListView's OnDataHint event to load records for just the items the ListView is actually interested in. As the user scrolls around, the range specified by OnDataHint changes, allowing me to free records that are not in the new range, and allocate new records as needed. This works fine, speed is tolerable, and the memory footprint is very low. I am currently evaluating TVirtualStringTree as a replacement for the TListView, mainly because I want to add the ability to expand/collapse records that span multiple lines (I can fudge it with the TListView by incrementing/decrementing the item count dynamically, but this is not as straight forward as using a real tree). For the most part, I have been able to port the TListView logic and have everything work as I need. I notice that TVirtualStringTree's virtual paridigm is vastly different, though. It does not have the same kind of OnDataHint functionality that TListView does (I can use the OnScroll event to fake it, which allows my memory buffer logic to continue working), and I can use the OnInitializeNode event to associate nodes with records that are allocated. However, once a tree node is initialized, it sees that it remains initialized for the lifetime of the tree. That is not good for me. As the user scrolls around and I remove records from memory, I need to reset those non-visual nodes without removing them from the tree completely, or losing their expand/collapse states. When the user scrolls them back into view, I can re-allocate the records and re-initialize the nodes. Basically, I want to make TVirtualStringTree act as much like TListView as possible, as far as its virtualization is concerned. I have seen that TVirtualStringTree has a ResetNode() method, but I encounter various errors whenever I try to use it. I must be using it wrong. I also thought of just storing a data pointer inside each node to my record buffers, and I allocate and free memory, update those pointers accordingly. The end effect does not work so well, either. Worse, my largest test log file has ~5 million records in it. If I initialize the TVirtualStringTree with that many nodes at one time (when the log display is unfiltered), the tree's internal overhead for its nodes takes up a whopping 260MB of memory (without any records being allocated yet). Whereas with the TListView, loading the same log file and all the memory logic behind it, I can get away with using just a few MBs. Any ideas?

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