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  • NHibernate Session DI from StructureMap in components

    - by Corey Coogan
    I know this is somewhat of a dead horse, but I'm not finding a satisfactory answer. First let me say, I am NOT dealing with a web app, otherwise managing NH Session is quite simple. I have a bunch of enterprise components. Those components have their own service layer that will act on multiple repositories. For example: Claim Component Claim Processing Service Claim Repository Billing Component Billing Service Billing REpository Policy Component PolicyLockService Policy Repository Now I may have a console, or windows application that needs to coordinate an operation that involves each of the services. I want to write the services to be injected with (DI) their required repositories. The Repositories should have an ISession, or similar, injected into them so that I can have this operation performed under one ISession/ITransaction. I'm aware of the Unit Of Work pattern and the many samples out there, but none of them showed DI. I'm also leery of [ThreadStatic] because this stuff can also be used from WCF and I have found enough posts describing how to do that. I've read about Business Conversations, but need something simple that each windows/console app can easily bootstrap since we have alot of these apps and some pretty inexperienced developers. So how can I configure StructureMap to inject the same ISession into each of the dependent repositories from an application? Here's a totally contrived and totally made up example without using SM (for clarification only - please don't spend energy critisizing): ConsoleApplication Main { using(ISession session = GetSession()) using(ITransaction trans = session.BeginTransaction()) { var policyRepo = new PolicyRepo(session); var policyService = new PolicyService(policyRepo); var billingRepo = new BillingRepo(session) var billingService = new BillingService(billingRepo); var claimRepo = new ClaimsRepo(session); var claimService = new ClaimService(claimRepo, policyService, billingService); claimService.FileCLaim(); trans.Commit(); } }

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  • How do I start up an NSRunLoop, and ensure that it has an NSAutoreleasePool that gets emptied?

    - by Nick Forge
    I have a "sync" task that relies on several "sub-tasks", which include asynchronous network operations, but which all require access to a single NSManagedObjectContext. Due to the threading requirements of NSManagedObjectContexts, I need every one of these sub-tasks to execute on the same thread. Due to the amount of processing being done in some of these tasks, I need them to be on a background thread. At the moment, I'm launching a new thread by doing this in my singleton SyncEngine object's -init method: [self performSelectorInBackground:@selector(initializeSyncThread) withObject:nil]; The -initializeSyncThread method looks like this: - (void)initializeSyncThread { self.syncThread = [NSThread currentThread]; self.managedObjectContext = [(MyAppDelegate *)[UIApplication sharedApplication].delegate createManagedObjectContext]; NSRunLoop *runLoop = [NSRunLoop currentRunLoop]; [runLoop run]; } Is this the correct way to start up the NSRunLoop for this thread? Is there a better way to do it? The run loop only needs to handle 'performSelector' sources, and it (and its thread) should be around for the lifetime of the process. When it comes to setting up an NSAutoreleasePool, should I do this by using Run Loop Observers to create the autorelease pool and drain it after every run-through?

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  • Building a formset dynamically

    - by vorpyg
    I initially wrote code to build a form dynamically, based on data from the DB, similar to what I described in my previous SO post. As SO user Daniel Roseman points out, he would use a formset for this, and now I've come to the realization that he must be completely right. :) My approach works, basically, but I can't seem to get validation across the entire form to be working properly (I believe it's possible, but it's getting quite complex, and there has to be a smarter way of doing it = Formsets!). So now my question is: How can I build a formset dynamically? Not in an AJAX way, I want each form's label to be populated with an FK value (team) from the DB. As I have a need for passing parameters to the form, I've used this technique from a previous SO post. With the former approach, my view code is (form code in previous link): def render_form(request): teams = Team.objects.filter(game=game) form_collection = [] for team in teams: f = SuggestionForm(request.POST or None, team=team, user=request.user) form_collection.append(f) Now I want to do something like: def render_form(request): teams = Team.objects.filter(game=game) from django.utils.functional import curry from django.forms.formsets import formset_factory formset = formset_factory(SuggestionForm) for team in teams: formset.form.append(staticmethod(curry(SuggestionForm, request.POST or None, team=team, user=request.user))) But the append bit doesn't work. What's the proper way of doing this? Thanks!

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  • Bi-directional view model syncing with "live" collections and properties (MVVM)

    - by Schneider
    I am getting my knickers in a twist recently about View Models (VM). Just like this guy I have come to the conclusion that the collections I need to expose on my VM typically contain a different type to the collections exposed on my business objects. Hence there must be a bi-directional mapping or transformation between these two types. (Just to complicate things, on my project this data is "Live" such that as soon as you change a property it gets transmitted to other computers) I can just about cope with that concept, using a framework like Truss, although I suspect there will be a nasty surprise somewhere within. Not only must objects be transformed but a synchronization between these two collections is required. (Just to complicate things I can think of cases where the VM collection might be a subset or union of business object collections, not simply a 1:1 synchronization). I can see how to do a one-way "live" sync, using a replicating ObservableCollection or something like CLINQ. The problem then becomes: What is the best way to create/delete items? Bi-directinal sync does not seem to be on the cards - I have found no such examples, and the only class that supports anything remotely like that is the ListCollectionView. Would bi-directional sync even be a sensible way to add back into the business object collection? All the samples I have seen never seem to tackle anything this "complex". So my question is: How do you solve this? Is there some technique to update the model collections from the VM? What is the best general approach to this?

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  • ASP.NET MVC Map String Url To A Route Value Object

    - by mwgriffiths
    I am creating a modular ASP.NET MVC application using areas. In short, I have created a greedy route that captures all routes beginning with {application}/{*catchAll}. Here is the action: // get /application/index public ActionResult Index(string application, object catchAll) { // forward to partial request to return partial view ViewData["partialRequest"] = new PartialRequest(catchAll); // this gets called in the view page and uses a partial request class to return a partial view } Example: The Url "/Application/Accounts/LogOn" will then cause the Index action to pass "/Accounts/LogOn" into the PartialRequest, but as a string value. // partial request constructor public PartialRequest(object routeValues) { RouteValueDictionary = new RouteValueDictionary(routeValues); } In this case, the route value dictionary will not return any values for the routeData, whereas if I specify a route in the Index Action: ViewData["partialRequest"] = new PartialRequest(new { controller = "accounts", action = "logon" }); It works, and the routeData values contains a "controller" key and an "action" key; whereas before, the keys are empty, and therefore the rest of the class wont work. So my question is, how can I convert the "/Accounts/LogOn" in the catchAll to "new { controller = "accounts", action = "logon" }"?? If this is not clear, I will explain more! :) Matt This is the "closest" I have got, but it obviously wont work for complex routes: // split values into array var routeParts = catchAll.ToString().Split(new char[] { '/' }, StringSplitOptions.RemoveEmptyEntries); // feels like a hack catchAll = new { controller = routeParts[0], action = routeParts[1] };

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  • sending email in php unable to use HTML tags

    - by JPro
    I am trying to send an email through the result sets generated in MySQL in PHP This is the code. <?php $txtMsg = '<table><th>Name</th>'; $txtMsg = ''; mysql_connect("localhost", "root", "pop") or die(mysql_error()); mysql_select_db("jpd") or die(mysql_error()); $oustanding = mysql_query("select Name from results") or die(mysql_error()); $num=mysql_num_rows($oustanding); while($row1 = mysql_fetch_array( $oustanding )) { ?> <tr> <td><h3><?php echo $row1['Name']; ?></h3></td> </tr> <?php $txtMsg .= "<tr><td>".$row1['Name']."</td></tr>"; } ini_set ( "SMTP", "xy.domain.com" ); $mail_to= '[email protected]'; $mail_from='[email protected]'; $mail_sub='OutStanding Results'; $mail_mesg=$txtMsg; //Check for success/failure of delivery if(mail($mail_to,$mail_sub,$mail_mesg,"From: $mail_from")) echo "<br><br>Email Successfully Sent!"; else echo "<br><br>Error Sending Email!"; } ?> The problem is , I want the results to be displayed in table format. But instead of processing the html tags, they are getting printed as well. How to get the email with table format? Thanks.

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  • Flipping View transition becomes clunky when using UIPickerViews with a large number of elements

    - by user302246
    I have a very simple app created with the Utility Application project template on XCode. My MainView has two UIPickerView components and two buttons. The FlipSideView has another UIPickerView. The pickers on the main view each have 4 segments and each segment has 8 rows. The picker on the flip side has just 1 segment with 8 rows. All rows on all pickers are just text. With just this setup, pressing the button to flip the view back and forth displays a noticeable delay before the animation actually starts, and then the animation actually seems to go faster than what it should, like it's trying to make up for the lost time. I removed the pickers in interface builder and loaded the app on the phone and the animation now seems natural. I also tried just one picker (the flipside one) and things still seem normal. So my current theory is that the number of objects involved in the main view is the cause. The thing is that I don't think it's that many (4 x 8 x 2 = 64), but I could be completely wrong. This is pretty much my first app so maybe I'm just doing something grossly wrong, or maybe the phone is has a lot more limited processing than I thought. I am thinking of creating the picker views with pickerView:viewForRow:forComponent:reusingView: to see if this hopefully performs better, but I'm not sure if this is just a waste of time. Any suggestions? Thanks Ruy P.S.: Testing on a 3G phone on 3.1.2

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  • php user authentication libraries / frameworks ... what are the options?

    - by es11
    I am using PHP and the codeigniter framework for a project I am working on, and require a user login/authentication system. For now I'd rather not use SSL (might be overkill and the fact that I am using shared hosting discourages this). I have considered using openID but decided that since my target audience is generally not technical, it might scare users away (not to mention that it requires mirroring of login information etc.). I know that I could write a hash based authentication (such as sha1) since there is no sensitive data being passed (I'd compare the level of sensitivity to that of stackoverflow). That being said, before making a custom solution, it would be nice to know if there are any good libraries or packages out there that you have used to provide semi-secure authentication? I am new to codeigniter, but something that integrates well with it would be preferable. Any ideas? (i'm open to criticism on my approach and open to suggestions as to why I might be crazy not to just use ssl). Thanks in advance. Update: I've looked into some of the suggestions. I am curious to try out zend-auth since it seems well supported and well built. Does anyone have experience with using zend-auth in codeigniter (is it too bulky?) and do you have a good reference on integrating it with CI? I do not need any complex authentication schemes..just a simple login/logout/password-management authorization system. Also, dx_auth seems interesting as well, however I am worried that it is too buggy. Has anybody else had success with this? I realized that I would also like to manage guest users (i.e. users that do not login/register) in a similar way to stackoverflow..so any suggestions that have this functionality would be great

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  • HttpWebRequest.BeginGetResponse() does not return the second time

    - by evilfred
    Hi, I make one HttpWebRequest and call GetResponse() on it to get a synchronous response. Then after processing that response, I make a new HttpWebRequest and call BeginGetResponse() on it. Since BeginGetResponse() is an asynchronous call I expect it to return right away, but it doesn't! Why not? Here is some stripped down sample code: HttpWebRequest request = RequestFactory.MakeSessionCreationRequest(); try { // Get the response from the server. using (WebResponse response = request.GetResponse()) { using (Stream responseStream = response.GetResponseStream()) { ; // Get the response. } } ; // Process the response. } catch (WebException e) { Logger("Caught WebException when attempting to connect: " + e); return; } // Make the second, asynchronous request. HttpWebRequest msgRequest = RequestFactory.MakeMessageRequest(); IAsyncResult result = msgRequest.BeginGetResponse( new AsyncCallback(HandleResponse), msgRequest); // PROBLEM: This line is never reached!!! Logger("Message send started");

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  • Strangely structured xml code finding last value of a certain type using java

    - by Damien.Bell
    Thus the structure is something like this: OasisReportMessagePayloadRTOReport_ItemReport_Data Under report data it's broken into categories: >>Zone >>Type >>Value >>Interval What I need to do is: Get the value if the type is equal to 'myType' and the interval value is the LARGEST. So an example of the xml might be (under report_data): OasisReport MessagePayload RTO REPORT_ITEM REPORT_DATA <zone>myZone1</zone> -- This should be the same in all reports since I only get them for 1 zone <type>myType</type> --This can change from line to line <value>12345</value>--This changes every interval <Interval>122</Interval> -- This is essentially how many 5 minute intervals have taken place since the beginning of a day, finding the "max" lets me know it's the newest data. Thereby I want to find stuff of "MyType" for the "max" interval and pull the Value (into a string, or a double, if not I can convert from string. Can someone help me with this task? Thanks! Note: I've used Xpath to handle things like this in the past, but it seems outlandish for this... as it's SO complex (since not all the reports live in the same report_item, and not all the types are the same in each report)

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  • Nested parsers in happy / infinite loop?

    - by McManiaC
    I'm trying to write a parser for a simple markup language with happy. Currently, I'm having some issues with infinit loops and nested elements. My markup language basicly consists of two elements, one for "normal" text and one for bold/emphasized text. data Markup = MarkupText String | MarkupEmph [Markup] For example, a text like Foo *bar* should get parsed as [MarkupText "Foo ", MarkupEmph [MarkupText "bar"]]. Lexing of that example works fine, but the parsing it results in an infinite loop - and I can't see why. This is my current approach: -- The main parser: Parsing a list of "Markup" Markups :: { [Markup] } : Markups Markup { $1 ++ [$2] } | Markup { [$1] } -- One single markup element Markup :: { Markup } : '*' Markups1 '*' { MarkupEmph $2 } | Markup1 { $1 } -- The nested list inside *..* Markups1 :: { [Markup] } : Markups1 Markup1 { $1 ++ [$2] } | Markup1 { [$1] } -- Markup which is always available: Markup1 :: { Markup } : String { MarkupText $1 } What's wrong with that approach? How could the be resolved? Update: Sorry. Lexing wasn't working as expected. The infinit loop was inside the lexer. Sorry. :) Update 2: On request, I'm using this as lexer: lexer :: String -> [Token] lexer [] = [] lexer str@(c:cs) | c == '*' = TokenSymbol "*" : lexer cs -- ...more rules... | otherwise = TokenString val : lexer rest where (val, rest) = span isValidChar str isValidChar = (/= '*') The infinit recursion occured because I had lexer str instead of lexer cs in that first rule for '*'. Didn't see it because my actual code was a bit more complex. :)

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  • How do I browse a Websphere MQ message without removing it?

    - by jmgant
    I'm writing a .NET Windows Forms application that will post a message to a Websphere MQ queue and then poll a different queue for a response. If a response is returned, the application will partially process the response in real time. But the response needs to stay in the queue so that a daily batch job, which also reads from the response queue, can do the rest of the processing. I've gotten as far as reading the message. What I haven't been able to figure out is how to read it without removing it. Here's what I've got so far. I'm an MQ newbie, so any suggestions will be appreciated. And feel free to respond in C#. Public Function GetMessage(ByVal msgID As String) As MQMessage Dim q = ConnectToResponseQueue() Dim msg As New MQMessage() Dim getOpts As New MQGetMessageOptions() Dim runThru = Now.AddMilliseconds(CInt(ConfigurationManager.AppSettings("responseTimeoutMS"))) System.Threading.Thread.Sleep(1000) 'Wait for one second before checking for the first response' While True Try q.Get(msg, getOpts) Return msg Catch ex As MQException When ex.Reason = MQC.MQRC_NO_MSG_AVAILABLE If Now > runThru Then Throw ex System.Threading.Thread.Sleep(3000) Finally q.Close() End Try End While Return Nothing 'Should never reach here' End Function NOTE: I haven't verified that my code actually removes the message. But that's how I understand MQ to work, and that appears to be what's happening. Please correct me if that's not the default behavior.

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  • Java problem with multiple threads when executing a runnable jar file

    - by Spi1988
    I have developed a Java Swing application, which uses the SwingWorker class to perform some long running tasks. When the application is run from the IDE (Netbeans), I can start multiple long running tasks simultaneously without any problem. I created a runnable jar file for the application, in order to be able to run it from outside the IDE. The application when run from this jar file works well with the only exception that it doesn't allow me to start 2 long running tasks simultaneously. When I start the first task (assume it takes 2 minitues to complete), every thing works fine, the UI does not freeze (it never freezes). However, when I try to run another task (assume it takes just 10 seconds, therefore it should finish before the first task) while the first task has not yet completed, nothing seems to happen. In reality, the second task would have started, and also finished its processing, however its results are only displayed once the first task completes. I dunno why this is happening. Is there some restriction on the number of threads which could run simultaneously on the JVM? Are there any jvm arguments which i could try to solve this problem. I hope i explained my problem well. Thanks in advance, Peter Bartolo

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  • iPhone/iPad : Check for invalid characters in a textbox made for Integers only

    - by JustinXXVII
    I noticed that the iPhone OS is pretty good about picking out Integer values when asked to. Specifically, if you use NSString *stringName = @"6("; int number = [stringName intValue]; the iPhone OS will pick out the 6 and turn the variable number into 6. However, in more complex mistypes, this also makes the int variable 6: NSString *stringName = @"6(5"; int number = [stringName intValue]; The iPhone OS misses the other digit, when what could have possibly been the user trying to enter the number 65, the OS only gets the number 6 out of it. I need a solution to check a string for invalid characters and return NO if there is anything other than an unsigned integer in a textbox. This is for iPad, and currently there is no numeric keyboard like the iPhone has, and I'm instead limited to the standard 123 keyboard. I was thinking that I need to use NSRange and somehow loop through the entire string in the textbox, and checking to see if the current character in the iteration is a number. I'm lost as far as that goes. I can think of testing it against zero, but zero is a valid integer. Can anyone help?

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  • Sys.WebForms.PageRequestManagerServerErrorException: .... The status code returned from the server w

    - by webnoob
    Hi All, I have seen a few posts regarding this issue but not one specific to my problem and I have no ideas as to what I need to do to debug this. I have some combo boxes on an aspx pages, when I select a value from the first one, it fills the second with value and so on with the third and fourth. This works with no problems until I wrap an asp.net UpdatePanel around the combo boxes and try to "ajaxify" the whole process so the page isn't dancing around. The exact error I get is: Sys.WebForms.PageRequestManagerServerErrorException: An unknown error occurred while processing the request on the server. The status code returned from the server was: 404 Some things to note: I am using URL rewriting - This is what I think is causing the problem The error will occur whenever I choose a selection for a SECOND time. This means that I could select a value from the first combo box and get the same error (so it is happening on the second postback - No matter which combo box it's from). I have tried setting the EnablePartialRendering="false" on teh scriptmanager but as I said, it works when not using ajax, so I don't know how to debug the issue. My server is Windows 2008 running IIS& with ASP.NET 2.0. I would really appreciate your help Thanks in advance.

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  • VS2010 : javascript intellisense : specifying properties for 'options' objects passed to methods

    - by Master Morality
    Since javascript intellisense actually seems to work in VS2010, I thought I might add some to those scripts I include in almost everything. The trouble is, on some complex functions, I use option objects instead of passing umpteen different parameters, like so: function myFunc(options){ var myVar1 = options.myVar1, myVar2 = options.myVar2, myVar3 = options.myVar3; ... } the trouble I am running into is, there doesn't seem to be a way to specify what properties options needs to have. I've tried this: function myFunc(options){ ///<summary>my func does stuff...</summary> ///<param name="options"> ///myVar1 : the first var ///myVar2 : the second var ///myVar3 : the third var ///</param> var myVar1 = options.myVar1, myVar2 = options.myVar2, myVar3 = options.myVar3; ... } but the line breaks are removed and all the property comments run together, making them stupidly hard to read. I've tried the <para> tags, but to no avail. If anyone has any ideas on how I might achieve this, please let me know. -Brandon

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  • python VTE Terminal weirdness

    - by mykhal
    i'm trying to use the terminal from python VTE binding (python-vte from debian squeeze) as a virtual terminal emulator (just for ANSI/control chars text processing) in interactive python console, everything looks (almost) all right: >>> import vte >>> term = vte.Terminal() >>> term.feed("a\nb") >>> print repr(term.get_text(lambda *a: True).rstrip()) 'a\n b' however, launching this code (little modified) as python script, different result is yielded: $ python vte_wiredness_1.py '' strangely enough, pasting the code back into the (new) interactive python session also yields empty string: >>> import vte >>> term = vte.Terminal() >>> term.feed("a\nb") >>> print repr(term.get_text(lambda *a: True).rstrip()) '' >>> first thing caming on my mind was that the only difference between the two cases is the timing - there had to be some delay before get_text. unfortunately, preluding get_text with some seconds sleep did not help then i thought it has something to do with X window environment. but the results are the same pure linux console (with some warning on missing graphics). i wonder what causes such an unpredictable behavior (interactive console - pasted vs typed, and it's not the delay.. ant the interactive console has nothing to do with the vte terminal object.. i guess) can someone explain what is happening? is it possible to use the VTE Term such way? that the "b" letter in the output is preceded by the space, is another strangeness (all consecutive lines are preceded by more spaces.. looks like I have to send carriage return before the string.) (the lambda *a: True get_text method argument i'm using is a dummy callback, it's is some SlotSelectedCallback.. for its explanation i'd be grateful as well :) )

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  • Umlaute from JSP-page are misinterpreted

    - by Karin
    I'm getting Input from a JSP page, that can contain Umlaute. (e.g. Ä,Ö,Ü,ä,ö,ü,ß). Whenever an Umlaut is entered in the Input field an incorrect value gets passed on. e.g. If an "ä" (UTF-8:U+00E4) gets entered in the input field, the String that is extracted from the argument is "ä" (UTF-8: U+00C3 and U+00A4) It seems to me as if the UTF-8 hex encoding (which is c3 a4 for an "ä") gets used for the conversion. How can I retrieved the correct value? Here are snippets from the current implementation The JSP-page passes the input value "pk" on to the processing logic: <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> ... <input type="text" name="<%=pk.toString()%>" value="<%=value%>" size="70"/> <button type="submit" title="Edit" value='Save' onclick="action.value='doSave';pk.value='<%=pk.toString()%>'"><img src="icons/run.png"/>Save</button> The value gets retrieved from args and converted to a string: UUID pk = UUID.fromString(args.get("pk")); //$NON-NLS-1$ String value = args.get(pk.toString()); Note: Umlaute that are saved in the Database get displayed correctly on the page.

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  • t-sql most efficient row to column? crosstab for xml path, pivot

    - by ajberry
    I am looking for the most performant way to turn rows into columns. I have a requirement to output the contents of the db (not actual schema below, but concept is similar) in both fixed width and delimited formats. The below FOR XML PATH query gives me the result I want, but when dealing with anything other than small amounts of data, can take awhile. select orderid ,REPLACE(( SELECT ' ' + CAST(ProductId as varchar) FROM _details d WHERE d.OrderId = o.OrderId ORDER BY d.OrderId,d.DetailId FOR XML PATH('') ),'&#x20;','') as Products from _orders o I've looked at pivot but most of the examples I have found are aggregating information. I just want to combine the child rows and tack them onto the parent. I should also point out I don't need to deal with the column names either since the output of the child rows will either be a fixed width string or a delimited string. For example, given the following tables: OrderId CustomerId ----------- ----------- 1 1 2 2 3 3 DetailId OrderId ProductId ----------- ----------- ----------- 1 1 100 2 1 158 3 1 234 4 2 125 5 3 101 6 3 105 7 3 212 8 3 250 for an order I need to output: orderid Products ----------- ----------------------- 1 100 158 234 2 125 3 101 105 212 250 or orderid Products ----------- ----------------------- 1 100|158|234 2 125 3 101|105|212|250 Thoughts or suggestions? I am using SQL Server 2k5. Example Setup: create table _orders ( OrderId int identity(1,1) primary key nonclustered ,CustomerId int ) create table _details ( DetailId int identity(1,1) primary key nonclustered ,OrderId int ,ProductId int ) insert into _orders (CustomerId) select 1 union select 2 union select 3 insert into _details (OrderId,ProductId) select 1,100 union select 1,158 union select 1,234 union select 2,125 union select 3,105 union select 3,101 union select 3,212 union select 3,250 using FOR XML PATH: select orderid ,REPLACE(( SELECT ' ' + CAST(ProductId as varchar) FROM _details d WHERE d.OrderId = o.OrderId ORDER BY d.OrderId,d.DetailId FOR XML PATH('') ),'&#x20;','') as Products from _orders o which outputs what I want, however is very slow for large amounts of data. One of the child tables is over 2 million rows, pushing the processing time out to ~ 4 hours. orderid Products ----------- ----------------------- 1 100 158 234 2 125 3 101 105 212 250

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  • SQL Server 2005 Blocking Problem (ASYNC_NETWORK_IO)

    - by ivankolo
    I am responsible for a third-party application (no access to source) running on IIS and SQL Server 2005 (500 concurrent users, 1TB data, 8 IIS servers). We have recently started to see significant blocking on the database (after months of running this application in production with no problems). This occurs at random intervals during the day, approximately every 30 minutes, and affects between 20 and 100 sessions each time. All of the sessions eventually hit the application time out and the sessions abort. The problem disappears and then gradually re-emerges. The SPID responsible for the blocking always has the following features: WAIT TYPE = ASYNC_NETWORK_IO The SQL being run is “(@claimid varchar(15))SELECT claimid, enrollid, status, orgclaimid, resubclaimid, primaryclaimid FROM claim WHERE primaryclaimid = @claimid AND primaryclaimid < claimid)”. This is relatively innocuous SQL that should only return one or two records, not a large dataset. NO OTHER SQL statements have been implicated in the blocking, only this SQL statement. This is parameterized SQL for which an execution plan is cached in sys.dm_exec_cached_plans. This SPID has an object-level S lock on the claim table, so all UPDATEs/INSERTs to the claim table are also blocked. HOST ID varies. Different web servers are responsible for the blocking sessions. E.g., sometimes we trace back to web server 1, sometimes web server 2. When we trace back to the web server implicated in the blocking, we see the following: There is always some sort of application related error in the Event Log on the web server, linked to the Host ID and Host Process ID from the SQL Session. The error messages vary, usually some sort of SystemOutofMemory. (These error messages seem to be similar to error messages that we have seen in the past without such dramatic consequences. We think was happening before, but didn’t lead to blocking. Why now?) No known problems with the network adapters on either the web servers or the SQL server. (In any event the record set returned by the offending query would be small.) Things ruled out: Indexes are regularly defragmented. Statistics regularly updated. Increased sample size of statistics on claim.primaryclaimid. Forced recompilation of the cached execution plan. Created a compound index with primaryclaimid, claimid. No networking problems. No known issues on the web server. No changes to application software on web servers. We hypothesize that the chain of events goes something like this: Web server process submits SQL above. SQL server executes the SQL, during which it acquires a lock on the claim table. Web server process gets an error and dies. SQL server session is hung waiting for the web server process to read the data set. SQL Server sessions that need to get X locks on parts of the claim table (anyone processing claims) are blocked by the lock on the claim table and remain blocked until they all hit the application time out. Any suggestions for troubleshooting while waiting for the vendor's assistance would be most welcome. Is there a way to force SQL Server to lock at the row/page level for this particular SQL statement only? Is there a way to set a threshold on ASYNC_NETWORK_IO waits only?

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  • Load Spikes on a Apache MySQL Server with Wordpress MU

    - by Vikram Goyal
    Hi there, I am trying to investigate the reasons for some mysterious load spikes on a Linux Apache server (2.2.14) running PHP 5.2.9 on a dedicated server with enough processing power and memory. My primary web application is a Wordpress MU (2.9.2) installation. I have investigated and ruled out DOS attack, MySQL or Apache configuration issues. The log files don't give me anything of interest, except to tell me that there is severe load. The load (which can go up to 100) just seems to come and go. It helps that I have a script that checks every 3 minutes for the load, and restarts Apache. Restarting it helps, and the server comes back, till it happens again. There seems to be no set time frame, or visitor numbers on the site that can trigger this. Even a low number of concurrent visitors (20) can trigger it. I am almost convinced that there is a rewrite loop somewhere that is causing Apache to go mad. Apache is trying to serve something that is causing it to spawn more and more processes till it keels over. My question is: Given that I am convinced that this is a rewrite issue or something similar, how can I try and figure out what the issue is? What should I monitor? Apache logs are voluminous, and not very helpful. Of course, if this is not the issue, then at least knowing what to look for will help me eliminate this as an issue and look for something else. Thanks! Vikram

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  • SSRS2005 timeout error

    - by jaspernygaard
    Hi I've been running around circles the last 2 days, trying to figure a problem in our customers live environment. I figured I might as well post it here, since google gave me very limited information on the error message (5 results to be exact). The error boils down to a timeout when requesting a certain report in SSRS2005, when a certain parameter is used. The deployment scenario is: Machine #1 Running reporting services (SQL2005, W2K3, IIS6) Machine #2 Running datawarehouse database (SQL2005, W2K3) which is the data source for #1 Both machines are running on the same vm cluster and LAN. The report requests a fairly simple SP - lets called it sp(param $a, param $b). When requested with param $a filled, it executes correctly. When using param $b, it times out after the global timeout periode has passed. If I run the stored procedure with param $b directly from sql management studio on #2, it returns the results perfectly fine (within 3-4s). I've profiled the datawarehouse database on #2 and when param $b is used, the query from the reporting service to the database, never reaches #2. The error message that I get upon timeout, when using param $b, when invoking the report directly from SSRS web interface is: "An error has occurred during report processing. Cannot read the next data row for the data set DataSet. A severe error occurred on the current command. The results, if any, should be discarded. Operation cancelled by user." The ExecutionLog for the SSRS does give me much information besides the error message rsProcessingAborted I'm running out of ideas of how to nail this problem. So I would greatly appreciate any comments, suggestions or ideas. Thanks in advance!

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  • Creating an API for an ASP.NET MVC site with rate-limiting and caching

    - by Maxim Z.
    Recently, I've been very interested in APIs, specifically in how to create them. For the purpose of this question, let's say that I have created an ASP.NET MVC site that has some data on it; I want to create an API for this site. I have multiple questions about this: What type of API should I create? I know that REST and oData APIs are very popular. What are the pros and cons of each, and how do I implement them? From what I understand so far, REST APIs with ASP.NET MVC would just be actions that return JSON instead of Views, and oData APIs are documented here. How do I handle writing? Reading from both API types is quite simple. However, writing is more complex. With the REST approach, I understand that I can use HTTP POST, but how do I implement authentication? Also, with oData, how does writing work in the first place? How do I implement basic rate-limiting and caching? From my past experience with APIs, these are very important things, so that the API server isn't overloaded. What's the best way to set these two things up? Can I get some sample code? Any code that relates to C# and ASP.NET MVC would be appreciated. Thanks in advance! While this is a broad question, I think it's not too broad... :) There are some similar questions to this one that are about APIs, but I haven't found any that directly address the questions I outlined here.

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  • Is this a right way to use NHibernate?

    - by Venemo
    I spent the rest of the evening reading StackOverflow questions and also some blog entries and links about the subject. All of them turned out to be very helpful, but I still feel that they don't really answer my question. So, I'm developing a simple web application. I'd like to create a reusable data access layer which I can later reuse in other solutions. 99% of these will be web applications. This seems to be a good excuse for me to learn NHibernate and some of the patterns around it. My goals are the following: I don't want the business logic layer to know ANYTHING about the inner workings of the database, nor NHibernate itself. I want the business logic layer to have the least possible number of assumptions about the data access layer. I want the data access layer as simplistic and easy-to-use as possible. This is going to be a simple project, so I don't want to overcomplicate anything. I want the data access layer to be as non-intrusive as possible. Will all this in mind, I decided to use the popular repository pattern. I read about this subject on this site and on various dev blogs, and I heard some stuff about the unit of work pattern. I also looked around and checked out various implementations. (Including FubuMVC contrib, and SharpArchitecture, and stuff on some blogs.) I found out that most of these operate with the same principle: They create a "unit of work" which is instantiated when a repository is instantiated, they start a transaction, do stuff, and commit, and then start all over again. So, only one ISession per Repository and that's it. Then the client code needs to instantiate a repository, do stuff with it, and then dispose. This usage pattern doesn't meet my need of being as simplistic as possible, so I began thinking about something else. I found out that NHibernate already has something which makes custom "unit of work" implementations unnecessary, and that is the CurrentSessionContext class. If I configure the session context correctly, and do the clean up when necessary, I'm good to go. So, I came up with this: I have a static class called NHibernateHelper. Firstly, it has a static property called CurrentSessionFactory, which upon first call, instantiates a session factory and stores it in a static field. (One ISessionFactory per one AppDomain is good enough.) Then, more importantly, it has a CurrentSession static property, which checks if there is an ISession bound to the current session context, and if not, creates one, and binds it, and it returns with the ISession bound to the current session context. Because it will be used mostly with WebSessionContext (so, one ISession per HttpRequest, although for the unit tests, I configured ThreadStaticSessionContext), it should work seamlessly. And after creating and binding an ISession, it hooks an event handler to the HttpContext.Current.ApplicationInstance.EndRequest event, which takes care of cleaning up the ISession after the request ends. (Of course, it only does this if it is really running in a web environment.) So, with all this set up, the NHibernateHelper will always be able to return a valid ISession, so there is no need to instantiate a Repository instance for the "unit of work" to operate properly. Instead, the Repository is a static class which operates with the ISession from the NHibernateHelper.CurrentSession property, and exposes some functionality through that. I'm curious, what do you think about this? Is it a valid way of thinking, or am I completely off track here?

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  • Alternate widgets and logic for ManyToManyField with Django forms

    - by Jaearess
    In my Django project, I have a simple ticket system. When creating a ticket, certain users have the ability to assign the ticket to other users, and to email the ticket to other users as well (this is used as an FYI for those users, so they're aware of the ticket, even though it's not assigned to them.) At the moment, the form for adding a ticket is simply the default Django form, with the "assigned_to" and "email_to" fields being ManyToManyFields, and therefore displayed as MultipleSelect widgets, each with a list of all users. Due to the relatively large number of users, and general awkwardness of the MultipleSelect widget, and alternate layout is now required. The desired layout is a pair of simple Select widgets side-by-side. The first has the option of "Assign to" or "Email to" and the second is a list of the users. Essentially, like this: [Assign to] [John Doe] [Email to] [Jane Roe] [Jack Smith], etc. Of course, since an arbitrary number of users can be assigned or emailed a ticket, there's a simple button that runs some Javascript to add another set of widgets, to allow the user to assign and email as many people as they need to. So far all of that is fairly simple and straight forward. However, the problem I have is using this widget setup/logic setup with Django forms. Instead of lists of users to assign to and email, instead we're getting back pairs of information, one a user and the other which list that user should be placed in. What I'm looking for, but have yet to find, is a way to offload the translation between how the user uses the form, and how Django understands the model to the form itself, so I don't have to manually do the processing of the data before passing it to the form in each place this form is used. Additionally, there's a review screen with the option to go back and change the form before submitting it, so a way to have the form translate both to and from this format would be extremely helpful.

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