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• Which fieldtype is best for storing PRICE values?

  - by BerggreenDK

  Hi there I am wondering whats the best "price field" in MSSQL for a shoplike structure? Looking at this overview: http://www.teratrax.com/sql_guide/data_types/sql_server_data_types.html We have datatypes called money, smallmoney, then we have decimal/numeric and lastly float and real Name, memory/disk-usage and value ranges: Money: 8 bytes (values: -922,337,203,685,477.5808 to +922,337,203,685,477.5807) Smallmoney: 4 bytes (values: -214,748.3648 to +214,748.3647) Decimal: 9 [default, min. 5] bytes (values: -10^38 +1 to 10^38 -1 ) Float: 8 bytes (values: -1.79E+308 to 1.79E+308 ) Real: 4 bytes (values: -3.40E+38 to 3.40E+38 ) My question is: is it really wise to store pricevalues in those types? what about eg. INT? Int: 4 bytes (values: -2,147,483,648 to 2,147,483,647) Lets say a shop uses dollars, they have cents, but I dont see prices being $49.2142342 so the use of a lot of decimals showing cents seems waste of SQL bandwidth. Secondly, most shops wouldn't show any prices near 200.000.000 (not in normal webshops at least... unless someone is trying to sell me a famous tower in Paris) So why not go for an int? An int is fast, its only 4 bytes and you can easily make decimals, by saving values in cents instead of dollars and then divide when you present the values. The other approach would be to use smallmoney which is 4 bytes too, but this will require the math part of the CPU to do the calc, where as Int is integer power... on the downside you will need to divide every single outcome. Are there any "currency" related problems with regionalsettings when using smallmoney/money fields? what will these transfer too in C#/.NET ? Any pros/cons? Go for integer prices or smallmoney or some other? Whats does your experience tell?

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• OO model for nsxmlparser when delegate is not self

  - by richard

  Hi, I am struggling with the correct design for the delegates of nsxmlparser. In order to build my table of Foos, I need to make two types of webservice calls; one for the whole table and one for each row. It's essentially a master-query then detail-query, except the master-query-result-xml doesn't return enough information so i then need to query the detail for each row. I'm not dealing with enormous amounts of data. Anyway - previously I've just used NSXMLParser *parser = [[NSXMLParser alloc]init]; [parser setDelegate:self]; [parser parse]; and implemented all the appropriate delegate methods in whatever class i'm in. In attempt at cleanliness, I've now created two separate delegate classes and done something like: NSXMLParser *xp = [[NSXMLParser alloc]init]; MyMasterXMLParserDelegate *masterParserDelegate = [[MyMasterXMLParser]alloc]init]; [xp setDelegate:masterParserDelegate]; [xp parse]; In addition to being cleaner (in my opinion, at least), it also means each of the -parser:didStartElement implementations don't spend most of the time trying to figure out which xml they're parsing. So now the real crux of the problem. Before i split out the delegates, i had in the main class that was also implementing the delegate methods, a class-level NSMutableArray that I would just put my objects-created-from-xml in when -parser:didEndElement found the 'end' of each record. Now the delegates are in separate classes, I can't figure out how to have the -parser:didEndElement in the 'detail' delegate class "return" the created object to the calling class. At least, not in a clean OO way. I'm sure i could do it with all sorts of nasty class methods. Does the question make sense? Thanks.

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• pulling a value from NSMutableDictionary

  - by Jared Gross

  I have a dictionary array with a key:@"titleLabel". I am trying to load a pickerView with ONE instance of each @"titleLabel" key so that if there are multiple objects with the same @"titleLabel" only one title will be displayed. I've done some research on this forum and looked at apples docs but haven't been able to put the puzzle together. Below is my code but I am having trouble pulling the values. Right now when I run this code it throws an error Incompatible pointer types sending 'PFObject *' to parameter of type 'NSString' which i understand but am just not sure how to remedy. Cheers! else { // found messages! self.objectsArray = objects; NSMutableDictionary *dict = [[NSMutableDictionary alloc] init]; for(id obj in self.objectsArray){ PFObject *key = [self.objectsArray valueForKey:@"titleLabel"]; if(![dict objectForKey:@"titleLabel"]){ [dict setValue:obj forKey:key]; } } for (id key in dict) { NSLog(@"Objects array is %d", [self.objectsArray count]); NSLog(@"key: %@, value: %@ \n", key, [dict objectForKey:key]); } [self.pickerView reloadComponent:0]; } }];` Here is where I define the PFObject and keys: PFObject *image = [PFObject objectWithClassName:@"Images"]; [image setObject:file forKey:@"file"]; [image setObject:fileType forKey:@"fileType"]; [image setObject:title forKey:@"titleLabel"]; [image setObject:self.recipients forKey:@"recipientIds"]; [image setObject:[[PFUser currentUser] objectId] forKey:@"senderId"]; [image setObject:[[PFUser currentUser] username] forKey:@"senderName"]; [image saveInBackground];

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• What is the fastest way to filter a list of strings when making an Intellisense/Autocomplete list?

  - by user559548

  Hello everyone, I'm writing an Intellisense/Autocomplete like the one you find in Visual Studio. It's all fine up until when the list contains probably 2000+ items. I'm using a simple LINQ statement for doing the filtering: var filterCollection = from s in listCollection where s.FilterValue.IndexOf(currentWord, StringComparison.OrdinalIgnoreCase) >= 0 orderby s.FilterValue select s; I then assign this collection to a WPF Listbox's ItemSource, and that's the end of it, works fine. Noting that, the Listbox is also virtualised as well, so there will only be at most 7-8 visual elements in memory and in the visual tree. However the caveat right now is that, when the user types extremely fast in the richtextbox, and on every key up I execute the filtering + binding, there's this semi-race condition, or out of sync filtering, like the first key stroke's filtering could still be doing it's filtering or binding work, while the fourth key stroke is also doing the same. I know I could put in a delay before applying the filter, but I'm trying to achieve a seamless filtering much like the one in Visual Studio. I'm not sure where my problem exactly lies, so I'm also attributing it to IndexOf's string operation, or perhaps my list of string's could be optimised in some kind of index, that could speed up searching. Any suggestions of code samples are much welcomed. Thanks.

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• Google Maps: Simple app not working on IE

  - by Peter Bridger

  We have a simple Google Maps traffic application up at: http://www.avonandsomerset.police.uk/newsroom/traffic/ For some reason it's recently stopped working in IE correctly. At this point in time it was using V2 of the API, so I've just upgraded it to use V3 - but it still won't work in IE. It works fine in Chrome & Firefox. But in all versions of IE I've tired (6,7,8) the Google Map doesn't load fully. The problem The Google Map DIV will generally load all the controls (Zoom, Powered by Google, map types) but the actual map tiles do not appear in IE. I can just see the grey background of the DIV What I've tried I've commented down the JavaScript code to just the following on the page, but it still has the same problem: <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script> <script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=false"></script> <script type="text/javascript" > var map; $(document).ready(function () { initialize(); // Set-up Google map }); function initialize() { var options = { zoom: 9, center: new google.maps.LatLng(51.335759, -2.870178), mapTypeId: google.maps.MapTypeId.ROADMAP }; map = new google.maps.Map(document.getElementById("googleMap"), options); } </script>

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• WCF data services (OData), query with inheritance limitation?

  - by Mathieu Hétu

  Project: WCF Data service using internally EF4 CTP5 Code-First approach. I configured entities with inheritance (TPH). See previous question on this topic: Previous question about multiple entities- same table The mapping works well, and unit test over EF4 confirms that queries runs smoothly. My entities looks like this: ContactBase (abstract) Customer (inherits from ContactBase), this entity has also several Navigation properties toward other entities Resource (inherits from ContactBase) I have configured a discriminator, so both Customer and Resource map to the same table. Again, everythings works fine on the Ef4 point of view (unit tests all greens!) However, when exposing this DBContext over WCF Data services, I get: - CustomerBases sets exposed (Customers and Resources sets seems hidden, is it by design?) - When I query over Odata on Customers, I get this error: Navigation Properties are not supported on derived entity types. Entity Set 'ContactBases' has a instance of type 'CodeFirstNamespace.Customer', which is an derived entity type and has navigation properties. Please remove all the navigation properties from type 'CodeFirstNamespace.Customer'. Stacktrace: at System.Data.Services.Serializers.SyndicationSerializer.WriteObjectProperties(IExpandedResult expanded, Object customObject, ResourceType resourceType, Uri absoluteUri, String relativeUri, SyndicationItem item, DictionaryContent content, EpmSourcePathSegment currentSourceRoot) at System.Data.Services.Serializers.SyndicationSerializer.WriteEntryElement(IExpandedResult expanded, Object element, ResourceType expectedType, Uri absoluteUri, String relativeUri, SyndicationItem target) at System.Data.Services.Serializers.SyndicationSerializer.<DeferredFeedItems>d__b.MoveNext() at System.ServiceModel.Syndication.Atom10FeedFormatter.WriteItems(XmlWriter writer, IEnumerable`1 items, Uri feedBaseUri) at System.ServiceModel.Syndication.Atom10FeedFormatter.WriteFeedTo(XmlWriter writer, SyndicationFeed feed, Boolean isSourceFeed) at System.ServiceModel.Syndication.Atom10FeedFormatter.WriteFeed(XmlWriter writer) at System.ServiceModel.Syndication.Atom10FeedFormatter.WriteTo(XmlWriter writer) at System.Data.Services.Serializers.SyndicationSerializer.WriteTopLevelElements(IExpandedResult expanded, IEnumerator elements, Boolean hasMoved) at System.Data.Services.Serializers.Serializer.WriteRequest(IEnumerator queryResults, Boolean hasMoved) at System.Data.Services.ResponseBodyWriter.Write(Stream stream) Seems like a limitation of WCF Data services... is it? Not much documentation can be found on the web about WCF Data services (OData) and inheritance specifications. How can I overpass this exception? I need these navigation properties on derived entities, and inheritance seems the only way to provide mapping of 2 entites on the same table with Ef4 CTP5... Any thoughts?

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• How would you start automating my job?

  - by Jurily

  At my new job, we sell imported stuff. In order to be able to sell said stuff, currently the following things need to happen for every incoming shipment: Invoice arrives, in the form of an email attachment, Excel spreadsheet Monkey opens invoice, copy-pastes the relevant part of three columns into the relevant parts of a spreadsheet template, where extremely complex calculations happen, like =B2*550 Monkey sends this new spreadsheet to boss (email if lucky, printer otherwise), who sets the retail price Monkey opens the reply, then proceeds to input the data into the production database using a client program that is unusable on so many levels it's not even worth detailing Monkey fires up HyperTerminal, types in "AT", disconnect Monkey sends text messages and emails to customers using another part of the horrible client program, one at a time I want to change Monkey from myself to software wherever possible. I've never written anything that interfaces with email, Excel, databases or SMS before, but I'd be more than happy to learn if it saves me from this. Here's my uneducated wishlist: Monkey asks Thunderbird (mail server perhaps?) for the attachment Monkey tells Excel to dump the spreadsheet into a more Jurily-friendly format, like CSV or something Monkey parses the output, does the complex calculations // TODO: find a way to get the boss-generated prices with minimal manual labor involved Monkey connects to the database, inserts data Monkey spams costumers Is all this feasible? If yes, where do I start reading? How would you improve it? What language/framework do you think would be ideal for this? What would you do about the boss?

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• How to (kindly) ask your users to upgrade from IE6?

  - by nickf

  It's no secret at all that IE6 has been a major roadblock to the advancement of the web over the last few years. I couldn't count the number of hours I've spent bashing my head against a wall trying to fix or debug IE6 issues. The way I see it, there are two types of IE6 user. a) the poor corporate schmoe whose IT department doesn't want to upgrade in case something breaks, and b) the mums and dads of the world who think the internet is the blue E on their desktop (and I don't mean that in a nasty way). There's probably a couple of people who know about all the other browsers, but still choose to run IE6. They get what they deserve, IMO. Anyway, getting to the point, I'd say that 90% of my IE6-using visitors are in the the mums and dads category - they're not stupid, they just don't know WHY they should upgrade to IE7 or Firefox or whatever. How do I educate these people without pissing them off? Is there a nice and friendly website I can direct these people to, which explains the reasons for upgrading in plain language? Any mention of "security" or "web standards" I think would just come across as scary. I've just seen http://www.whatbrowser.org which seems to fit the bill nicely. It explains in very basic terms: what a web browser is why you'd want to upgrade it how old your current browser is (subtle hint to those with a 9 year old browser) ..aaaand it's in 22 languages. It's from Google but displays no bias (it links to Firefox, Chrome, Opera, Safari, Internet Explorer displayed in a random order).

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• What do I name classes whose only purpose is to act as a structure?

  - by Sergio Tapia

  For example, take my Actor class: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Drawing; namespace FreeIMDB { class Actor { public string Name { get; set; } public Image Portrait { get; set; } public DateTime DateOfBirth { get; set; } public List<string> ActingRoles { get; set; } public List<string> WritingRoles { get; set; } public List<string> ProducingRoles { get; set; } public List<string> DirectingRoles { get; set; } } } This class will only be used to stuff information into it, and allow other developers to get their values. What are these types of classes officially called? What is the correct nomenclature?

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• C# How to create various objects at runtime that can hold strongly typed data?

  - by JL

  Is it possible to create objects at runtime without having to have hard coded class definitions, then populate properties with primitives or even strongly typed data types? For example: Lets say I want to an XML config file that could hold configuration values for connecting to various systems in an SOA application. In C# I read in these values, but for each system the properties are different (e.g: SQL might have a connection string, while SharePoint might need a username + password + domain + url, while yet an smtp server would need username + password + port + url) So instead of creating static classes as follows public class SharePointConfiguration or public class SQLConfiguration, then have each class with custom properties (this is cumbersome) Is there not a more preferred way to achieve this, without using 1990's methods, in otherwords it would still be nice to have intellisense and code completion and named properties. Since this collection of properties (object) would be passed within the class and possible to other classes from function to function I am also wondering where this class definition would get defined if its all happening at run time. Any recommendations, and hope the question was clear enough. Would like to use language features, not hacks. Thank you.

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• check properties of two objects for changes

  - by k-hoffmann

  Hi, i have to develop a mechanism to check two object properties for changes. All properties which are needed to check are marked with an attribute. Atm i - read all properties from acutal object via linq - read the corresponding property from old object - fill an own object with the two properties (old and new value) In Code the call to the workerclass looks like this public void CreateHistoryMap(BaseEntity actual, BaseEntity old) { CreateHistoryMap(actualEntity, oldEntity) .ForEach(mapEntry => CreateHistoryEntry(mapEntry), mapEntry => IfChangesDetected(mapEntry)); } CreateHistoryMap builds up the HistoryMapEntry which contains the two properties. CreateHistoryEntry build up the object which is saved to database, the IfChangesDetected check the object for changes. I have to handle own special application types to generate history values to database (like concatinating list values and so on). My problem is now, that i have to read the values of the properties twice - for change detection - and for the concreate CreateHistoryEntry How can i eliminate this problem or how can i implement the change tracking scenario with the nice c# 3.5 features? Thanks a lot.

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• page.insert_html not rendering partial correctly

  - by mathee

  The following is in the text_field. = f.text_field :title, :size => 50, :onchange => remote_function(:update => :suggestions, :url => {:action => :display_question_search_results}) The following is in display_questions_search_results.rjs. page.insert_html :bottom, 'suggestions', :partial => 'suggestions' Whenever the user types, I'd like to search the database for any tuples that match the keywords in the text field. Then, display those results. But, at the moment, _suggestions.haml only contains the word "suggestions!!". But, instead of seeing "suggestions!!" in the suggestions div tag, I get: try { Element.insert("suggestions", { bottom: "suggestions!!" }); } catch (e) { alert('RJS error:\n\n' + e.toString()); alert('Element.insert(\"suggestions\", { bottom: \"suggestions!!\" });'); throw e } I've been trying to find out why this is being done, but the previously asked questions I found seem more complicated than what I'm doing...

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• JQuery Tabbed Nav Menu and PHP Forms Question?

  - by SlAcKeR

  I'm using a JQuery Tabbed Menu which holds different types of forms and when I select a different form located under a different tab and submit the form the tab will jump to the default tab instead of the current tab the form is located in. I was wondering how would I go about fixing this so that when the form is submitted the current tab is still selected, is it the JQuery or PHP problem? Here is the JQuery. $(document).ready(function() { //When page loads... $(".form-content").hide(); //Hide all content var firstMenu = $("#home-menu ul li:first"); firstMenu.show(); firstMenu.find("a").addClass("selected-link"); //Activate first tab $(".form-content:first").show(); //Show first tab content //On Click Event $("#home-menu ul li").click(function() { $("#home-menu ul li a").removeClass("selected-link"); //Remove any "selected-link" class $(this).find("a").addClass("selected-link"); //Add "selected-link" class to selected tab $(".form-content").hide(); //Hide all tab content var activeTab = $(this).find("a").attr("href"); //Find the href attribute value to identify the selected-link tab + content $(activeTab).fadeIn(); //Fade in the selected-link ID content return false; }); });

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• Rails and SWFUpload: Sporadic Failure on Upload and Response Issue

  - by Gimli

  I've got SWFUpload version 2.5 beta 3 attached to my Rails 2.3.2 application and it works great 75% of the time. The other 25%, I get types of failure. The first failure is a failure to upload. The activity starts, but never actually sends the file to the servers. In my JS, when setting breakpoints, it stops between setting the post params and starting the upload (last two lines below): var params = { "authenticity_token": authToken, "photo[name]": $("#photo_name").val(), "photo[description]": $("#photo_description").val(), "photo[post_id]": $("#post_id").val() }; params[keyName] = key; swfu.setPostParams(params); swfu.startUpload(); It just occurred to me that the file might not being queued, but I've got a handler attached to show the file name in a text box and that works consistently. The second issue is this: Sometimes the response string is truncated. I'm rendering a partial in Rails without a layout to show the uploaded file data in my layout. Most of the time this partial comes through fine, but sometimes it comes through as only the first line, or only parts of the first several lines. The variables seem to be coming through into the view just fine. Any ideas? Thanks!

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• Drupal: allowing users to sign up to content using a form

  - by james6848

  My apologies if this is a little broad, but I'm struggling to know where to start here! OK, so I have a Drupal site and I need users to be able to sign up for certain content, here is the workflow in detail: I need a form within a block consisting of the following elements: First Name (required) Last Name (required) Organisation (optional) Email Address (required) Then there will be a choice of content to sign up to (using checkboxes): Policy Bulletin Action News eBulletin (which only members can sign up to) Then the usual submit button of course! Upon submission, users will: 1) Be taken to a confirmation page, or 2) Be informed about incorrectly filled in fields, and/or the need to become a user to be able to sign up for the eBulletin. Users will then receive an email when new content of the type(s) they signed up to is created, along with a link to the node. There should be details about how to unsubscribe within this email. I have used the Subscriptions module in the past, but I am not sure if it is possible to use a sign-up form with it. Plus, there is the added complexity that one of the content types, eBulletin, is only available for site members. Like I say, I'm struggling to know where to start, and any ideas would be gratefully received!

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• Iterating over member typed collection fails when using untyped reference to generic object

  - by Alexander Pavlov

  Could someone clarify why iterate1() is not accepted by compiler (Java 1.6)? I do not see why iterate2() and iterate3() are much better. This paragraph is added to avoid silly "Your post does not have much context to explain the code sections; please explain your scenario more clearly." protection. import java.util.Collection; import java.util.HashSet; public class Test<T> { public Collection<String> getCollection() { return new HashSet<String>(); } public void iterate1(Test test) { for (String s : test.getCollection()) { // ... } } public void iterate2(Test test) { Collection<String> c = test.getCollection(); for (String s : c) { // ... } } public void iterate3(Test<?> test) { for (String s : test.getCollection()) { // ... } } } Compiler output: $ javac Test.java Test.java:11: incompatible types found : java.lang.Object required: java.lang.String for (String s : test.getCollection()) { ^ Note: Test.java uses unchecked or unsafe operations. Note: Recompile with -Xlint:unchecked for details. 1 error

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• Arrays not matching correctly

  - by Nick Gibson

  userAnswer[] holds the string of the answer the user types in and is comparing it to answers[] to see if they match up and then spits out correct or wrong. j is equal to the question number. So if j was question 6, answers[j] should refer to answers[6] right? Then userAnswer[6] should compare to answers[6] and match if its correct. But its giving me wrong answers and displaying the answer I typed as correct. int abc, loopCount = 100; int j = quesNum, overValue, forLoop = 100; for (int loop = 1; loop < loopCount; loop++) { aa = r.nextInt(10+1); abc = (int) aa; String[] userAnswer = new String[x]; JOptionPane.showMessageDialog(null,abc); if(abc < x) { userAnswer[j] = JOptionPane.showInputDialog(null,"Question "+quesNum+"\n"+questions[abc]+"\n\nA: "+a[abc]+"\nB: "+b[abc]+"\nC: "+c[abc]+"\nD: "+d[abc]); if(userAnswer[j].equals(answers[j])) { JOptionPane.showMessageDialog(null,"Correct. \nThe Correct Answer is "+answers[abc]); } else { JOptionPane.showMessageDialog(null,"Wrong. \n The Correct Answer is "+answers[abc]); }//else }//if }//for

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• PHP Outputting File Attachments with Headers

  - by OneNerd

  After reading a few posts here I formulated this function which is sort of a mishmash of a bunch of others: function outputFile( $filePath, $fileName, $mimeType = '' ) { // Setup $mimeTypes = array( 'pdf' => 'application/pdf', 'txt' => 'text/plain', 'html' => 'text/html', 'exe' => 'application/octet-stream', 'zip' => 'application/zip', 'doc' => 'application/msword', 'xls' => 'application/vnd.ms-excel', 'ppt' => 'application/vnd.ms-powerpoint', 'gif' => 'image/gif', 'png' => 'image/png', 'jpeg' => 'image/jpg', 'jpg' => 'image/jpg', 'php' => 'text/plain' ); // Send Headers //-- next line fixed as per suggestion -- header('Content-Type: ' . $mimeTypes[$mimeType]); header('Content-Disposition: attachment; filename="' . $fileName . '"'); header('Content-Transfer-Encoding: binary'); header('Accept-Ranges: bytes'); header('Cache-Control: private'); header('Pragma: private'); header('Expires: Mon, 26 Jul 1997 05:00:00 GMT'); readfile($filePath); } I have a php page (file.php) which does something like this (lots of other code stripped out): // I run this thru a safe function not shown here $safe_filename = $_GET['filename']; outputFile ( "/the/file/path/{$safe_filename}", $safe_filename, substr($safe_filename, -3) ); Seems like it should work, and it almost does, but I am having the following issues: When its a text file, I am getting a strange symbol as the first letter in the text document When its a word doc, it is corrupt (presumably that same first bit or byte throwing things off). I presume all other file types will be corrupt - have not even tried them Any ideas on what I am doing wrong? Thanks - UPDATE: changed line of code as suggested - still same issue.

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• Java: using generic wildcards with subclassing

  - by gibberish

  Say I have a class Foo, a class A and some subclass B of A. Foo accepts A and its sublclasses as the generic type. A and B both require a Foo instance in their constructor. I want A's Foo to be of type A , and B's Foo to be of type B or a superclass of B. So in effect, So I only want this: Foo<X> bar = new Foo<X>; new B(bar); to be possible if X is either A, B, or a both subclass of A and superclass of B. So far this is what I have: class Foo<? extends A>{ //construct } class A(Foo<A> bar){ //construct } class B(Foo<? super B> bar){ super(bar); //construct } The call to super(...) doesn't work, because <A> is stricter than <? super B>. Is it somehow possible to use the constructor (or avoid code duplication by another means) while enforcing these types? Edit: Foo keeps a collection of elements of the generic parameter type, and these elements and Foo have a bidirectional link. It should therefore not be possible to link an A to a Foo.

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• Database schema for Product Properties

  - by Chemosh

  As so many people I'm looking for a Products /Product Properties database schema. I'm using Ruby on Rails and (Thinking) Sphinx for faceted searches. Requirements: Adding new product types and their options should not require a change to the database schema Support faceted searches using Sphinx. Solutions I've come across: (See Bill Karwin's answer) Option 1: Single Table Inheritance Not an option really. The table would contain way to many columns. Option 2: Class Table Inheritance Ruby on Rails caches the database schema on start-up which means a restart whenever a new type of product is introduced. If you have a size able product catalog this could mean hundreds of tables. Option 3: Serialized LOB Kills being able to do faceted searches without heavy application logic. Option 4: Entity-Attribute-Value For testing purposes, EAV worked fine. However it could quickly become a mess and a maintenance hell as you add more and more options (e.g. when an option increase the prices or delivery time). What option should I go with? What other solutions are out there? Is there a silver bullet (ha) I overlooked?

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• map operator [] operands

  - by Jamie Cook

  Hi all I have the following in a member function int tt = 6; vector<set<int>>& temp = m_egressCandidatesByDestAndOtMode[tt]; set<int>& egressCandidateStops = temp.at(dest); and the following declaration of a member variable map<int, vector<set<int>>> m_egressCandidatesByDestAndOtMode; However I get an error when compiling (Intel Compiler 11.0) 1>C:\projects\svn\bdk\Source\ZenithAssignment\src\Iteration\PtBranchAndBoundIterationOriginRunner.cpp(85): error: no operator "[]" matches these operands 1> operand types are: const std::map<int, std::vector<std::set<int, std::less<int>, std::allocator<int>>, std::allocator<std::set<int, std::less<int>, std::allocator<int>>>>, std::less<int>, std::allocator<std::pair<const int, std::vector<std::set<int, std::less<int>, std::allocator<int>>, std::allocator<std::set<int, std::less<int>, std::allocator<int>>>>>>> [ const int ] 1> vector<set<int>>& temp = m_egressCandidatesByDestAndOtMode[tt]; 1> ^ I know it's got to be something silly but I can't see what I've done wrong.

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• ADO.NET DataTable/DataRow Thread Safety

  - by Allen E. Scharfenberg

  Introduction A user reported to me this morning that he was having an issue with inconsistent results (namely, column values sometimes coming out null when they should not be) of some parallel execution code that we provide as part of an internal framework. This code has worked fine in the past and has not been tampered with lately, but it got me to thinking about the following snippet: Code Sample lock (ResultTable) { newRow = ResultTable.NewRow(); } newRow["Key"] = currentKey; foreach (KeyValuePair<string, object> output in outputs) { object resultValue = output.Value; newRow[output.Name] = resultValue != null ? resultValue : DBNull.Value; } lock (ResultTable) { ResultTable.Rows.Add(newRow); } (No guarantees that that compiles, hand-edited to mask proprietery information.) Explanation We have this cascading type of locking code other places in our system, and it works fine, but this is the first instance of cascading locking code that I have come across that interacts with ADO .NET. As we all know, members of framework objects are usually not thread safe (which is the case in this situation), but the cascading locking should ensure that we are not reading and writing to ResultTable.Rows concurrently. We are safe, right? Hypothesis Well, the cascading lock code does not ensure that we are not reading from or writing to ResultTable.Rows at the same time that we are assigning values to columns in the new row. What if ADO .NET uses some kind of buffer for assigning column values that is not thread safe--even when different object types are involved (DataTable vs. DataRow)? Has anyone run into anything like this before? I thought I would ask here at StackOverflow before beating my head against this for hours on end :) Conclusion Well, the consensus appears to be that changing the cascading lock to a full lock has resolved the issue. That is not the result that I expected, but the full lock version has not produced the issue after many, many, many tests. The lesson: be wary of cascading locks used on APIs that you do not control. Who knows what may be going on under the covers!

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• Best way to migrate export/import from SQL Server to oracle

  - by matao

  Hi guys! I'm faced with needing access for reporting to some data that lives in Oracle and other data that lives in a SQL Server 2000 database. For various reasons these live on different sides of a firewall. Now we're looking at doing an export/import from sql server to oracle and I'd like some advice on the best way to go about it... The procedure will need to be fully automated and run nightly, so that excludes using the SQL developer tools. I also can't make a live link between databases from our (oracle) side as the firewall is in the way. The data needs to be transformed in the process from a star schema to a de-normalised table ready for reporting. What I'm thinking about is writing a monster query for SQL Server (which I mostly have already) that will denormalise and read out the data from SQL Server into a flat file using the sql server equivalent of sqlplus as a scheduled task, dump into a Well Known Location, then on the oracle side have a cron job that copies down the file and loads it with sql loader and rebuilds indexes etc. This is all doable, but very manual. Is there one or a combination of FOSS or standard oracle/SQL Server tools that could automate this for me? the Irreducible complexity is the query on one side and building indexes on the other, but I would love to not have to write the CSV dumping detail or the SQL loader script, just say dump this view out to CSV on one side, and on the other truncate and insert into this table from CSV and not worry about mapping column names and all other arcane sqlldr voodoo... best practices? thoughts? comments? edit: I have about 50+ columns all of varying types and lengths in my dataset, which is why I'd prefer to not have to write out how to generate and map each single column...

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• passing an "unknown enumeration" to a method

  - by firoso

  I'm currently trying to make a class that can register strings as identifiers and accociate them with different types of Enumerations, these enumerations are being evaluated only in so much that I am ensuring that when it's used, that the parameter passed to broadcast (messageType) is an instance of the associated Enum Type. This would work something like this: Diagnostics.RegisterIdentifier("logger", typeof(TestEnum)); Diagnostics.Broadcast("logger", TestEnum.Info, null, "Hello World", null); here's the code I currently have, I need to be able to verify that messageTypesEnum is contained in messageTypesFromIdentifier. private static Dictionary<string, Type> identifierMessageTypeMapping = new Dictionary<string, Type>(); private static List<IListener> listeners = new List<IListener>(); public static void RegisterIdentifier(string identifier, Type messageTypesEnum) { if (messageTypesEnum.BaseType.FullName == "System.Enum") { identifierMessageTypeMapping.Add(identifier, messageTypesEnum); } else { throw new ArgumentException("Expected type of messageTypesEnum to derive from System.Enum", "messageTypesEnum"); } } public static void Broadcast(string identifier, object messageType, string metaIdentifier, string message, Exception exception) { if (identifierMessageTypeMapping.ContainsKey(identifier)) { Type messageTypesFromIdentifier = identifierMessageTypeMapping[identifier]; foreach (var listener in listeners) { DiagnosticsEvent writableEvent = new DiagnosticsEvent(identifier, messageType, metaIdentifier, message, exception); listener.Write(writableEvent); } } }

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• changing the serialization procedure for a graph of objects (.net framework)

  - by pierusch

  Hello I'm developing a scientific application using .net framework. The application depends heavily upon a large data structure (a tree like structure) that has been serialized using a standard binaryformatter object. The graph structure looks like this: <serializable()>Public class BigObjet inherits list(of smallObject) end class <serializable()>public class smallObject inherits list(of otherSmallerObjects) end class ... The binaryFormatter object does a nice job but it's not optimized at all and the entire data structure reaches around 100Mb on my filesystem. Deserialization works too but it's pretty slow (around 30seconds on my quad core). I've found a nice .dll on codeproject (see "optimizing serialization...") so I wrote a modified version of the classes above overriding the default serialization/deserialization procedure reaching very good results. The problem is this: I can't lose the data previosly serialized with the old version and I'd like to be able to use the new serialization/deserialization method. I have some ideas but I'm pretty sure someone will be able to give me a proper and better advice ! use an "helper" graph of objects who takes care of the entire serialization/deserialization procedure reading data from the old format and converting them into the classes I nedd. This could work but the binaryformatter "needs" to know the types being serialized so........ :( modify the "old" graph to include a modified version of serialization procedure...so I'll be able to deserialize old file and save them with the new format......this doesn't sound too good imho. well any help will be higly highly appreciated :)

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