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• Access 2007 not allowing user to delete record in subform

  - by Todd McDermid

  Good day... The root of my issue is that there's no context menu allowing the user to delete a row from a form. The "delete" button on the ribbon is also disabled. In Access 2003, apparently this function was available, but since our recent "upgrade" to 2007 (file is still in MDB format) it's no longer there. Please keep in mind I'm not an Access dev, nor did I create this app - I inherited support for it. ;) Now for the details, and what I've tried. The form in question is a subform on a larger form. I've tried turning "AllowDeletes" on on both forms. I've checked the toolbar and ribbon properties on the forms to see if they loaded some custom stuff, but no. I've tried changing the "record locks" to "on edit", no joy. I examined the query to see if it was "too complicated" to permit a delete - as far as I can tell, it's a very simple two (linked) table join. Compared to another form in this app that does permit row deletes, it has a much more complicated (multi-join, built on queries) query. Is there a resource that would describe the required conditions for allowing deletes? Thanks in advance...

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• Simplifying for-if messes with better structure?

  - by HH

  # Description: you are given a bitwise pattern and a string # you need to find the number of times the pattern matches in the string # any one liner or simple pythonic solution? import random def matchIt(yourString, yourPattern): """find the number of times yourPattern occurs in yourString""" count = 0 matchTimes = 0 # How can you simplify the for-if structures? for coin in yourString: #return to base if count == len(pattern): matchTimes = matchTimes + 1 count = 0 #special case to return to 2, there could be more this type of conditions #so this type of if-conditionals are screaming for a havoc if count == 2 and pattern[count] == 1: count = count - 1 #the work horse #it could be simpler by breaking the intial string of lenght 'l' #to blocks of pattern-length, the number of them is 'l - len(pattern)-1' if coin == pattern[count]: count=count+1 average = len(yourString)/matchTimes return [average, matchTimes] # Generates the list myString =[] for x in range(10000): myString= myString + [int(random.random()*2)] pattern = [1,0,0] result = matchIt(myString, pattern) print("The sample had "+str(result[1])+" matches and its size was "+str(len(myString))+".\n" + "So it took "+str(result[0])+" steps in average.\n" + "RESULT: "+str([a for a in "FAILURE" if result[0] != 8])) # Sample Output # # The sample had 1656 matches and its size was 10000. # So it took 6 steps in average. # RESULT: ['F', 'A', 'I', 'L', 'U', 'R', 'E']

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• Problems with Backbone.Model callback and THIS

  - by Rev. Samuel

  I'm building a simple weather widget. The current weather conditions are read out of the National Weather Service xml file and then I want to parse and store the relevant data in the model but the callback for the $.ajax won't connect (the way I'm doing it). var Weather = Backbone.Model.extend({ initialize: function(){ _.bindAll( this, 'update', 'startLoop', 'stopLoop' ); this.startLoop(); }, startLoop: function(){ this.update(); this.interval = window.setInterval( _.bind( this.update, this ), 1000 * 60 * 60 ); }, stopLoop: function(){ this.interval = window.clearInterval( this.interval ); }, store: function( data ){ this.set({ icon : $( data ).find( 'icon_url_name' ).text() }); }, update: function(){ $.ajax({ type: 'GET', url: 'xml/KROC.xml', datatype: 'xml' }) .done( function( data ) { var that = this; that.store( $( data ).find( 'current_observation' )[ 0 ] ); }); } }); var weather = new Weather(); The data is read correctly but I can't get the done function of the call back to call the store function. (I would be happy if the "done" would just parse and then do "this.set". Thanks in advance for your help.

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• How to keep Java Frame from waiting?

  - by pypmannetjies

  I am writing a genetic algorithm that approximates an image with a polygon. While going through the different generations, I'd like to output the progress to a JFrame. However, it seems like the JFrame waits until the GA's while loop finishes to display something. I don't believe it's a problem like repainting, since it eventually does display everything once the while loop exits. I want to GUI to update dynamically even when the while loop is running. Here is my code: while (some conditions) { //do some other stuff gui.displayPolygon(best); gui.displayFitness(fitness); gui.setVisible(true); } public void displayPolygon(Polygon poly) { BufferedImage bpoly = ImageProcessor.createImageFromPoly(poly); ImageProcessor.displayImage(bpoly, polyPanel); this.setVisible(true); } public static void displayImage(BufferedImage bimg, JPanel panel) { panel.removeAll(); panel.setBounds(0, 0, bimg.getWidth(), bimg.getHeight()); JImagePanel innerPanel = new JImagePanel(bimg, 25, 25); panel.add(innerPanel); innerPanel.setLocation(25, 25); innerPanel.setVisible(true); panel.setVisible(true); }

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• Group and sort blog posts by date in Rails

  - by Senthil

  I've searched all over web and have not found the answer. I'm trying to have a very standard archive option for my blog based on date. A request to url blog.com/archive/2009 shows all posts in 2009, blog.com/archive/2009/11 shows all posts in November 2009 etc. I found two different of code but not very helpful to me. def display_by_date year = params[:year] month = params[:month] day = params[:day] day = '0'+day if day && day.size == 1 @day = day if (year && month && day) render(:template => "blog/#{year}/#{month}/#{date}") elsif year render(:template => "blog/#{year}/list") end end def archive year = params[:year] month = params[:month] day = params[:day] day = '0'+day if day && day.size == 1 if (year && month && day) @posts_by_month = Blog.find(:all, :conditions => ["year is?", year]) else @posts_by_month = Blog.find(:all).group_by { |post| post.created_at.strftime("%B") } end end Any help is appreciated.

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• Running a Model::find in for loop in cakephp v1.3

  - by Gaurav Sharma

  Hi all, How can I achieve the following result in cakephp: In my application a Topic is related to category, category is related to city and city is finally related to state in other words: topic belongs to category, category belongs to city , city belongs to state.. Now in the Topic controller's index action I want to find out all the topics and it's city and state. How can I do this. I can easily do this using a custom query ($this-Model-query() function ) but then I will be facing pagination difficulties. I tried doing like this function index() { $this->Topic->recursive = 0; $topics = $this->paginate(); for($i=0; $i<count($topics);$i++) { $topics[$i]['City'] = $this->Topic->Category->City->find('all', array('conditions' => array('City.id' => $topics[$i]['Category']['city_id']))); } $this->set(compact('messages')); } The method that I have adopted is not a good one (running query in a loop) Using the recursive property and setting it to highest value (2) will degrade performance and is not going to yield me state information. How shall I solve this ? Please help Thanks

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• What is the purpose of unit testing an interface repository

  - by ahsteele

  I am unit testing an ICustomerRepository interface used for retrieving objects of type Customer. As a unit test what value am I gaining by testing the ICustomerRepository in this manner? Under what conditions would the below test fail? For tests of this nature is it advisable to do tests that I know should fail? i.e. look for id 4 when I know I've only placed 5 in the repository I am probably missing something obvious but it seems the integration tests of the class that implements ICustomerRepository will be of more value. [TestClass] public class CustomerTests : TestClassBase { private Customer SetUpCustomerForRepository() { return new Customer() { CustId = 5, DifId = "55", CustLookupName = "The Dude", LoginList = new[] { new Login { LoginCustId = 5, LoginName = "tdude" }, new Login { LoginCustId = 5, LoginName = "tdude2" } } }; } [TestMethod] public void CanGetCustomerById() { // arrange var customer = SetUpCustomerForRepository(); var repository = Stub<ICustomerRepository>(); // act repository.Stub(rep => rep.GetById(5)).Return(customer); // assert Assert.AreEqual(customer, repository.GetById(5)); } } Test Base Class public class TestClassBase { protected T Stub<T>() where T : class { return MockRepository.GenerateStub<T>(); } } ICustomerRepository and IRepository public interface ICustomerRepository : IRepository<Customer> { IList<Customer> FindCustomers(string q); Customer GetCustomerByDifID(string difId); Customer GetCustomerByLogin(string loginName); } public interface IRepository<T> { void Save(T entity); void Save(List<T> entity); bool Save(T entity, out string message); void Delete(T entity); T GetById(int id); ICollection<T> FindAll(); }

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• How do you unit-test a method with complex input-output

  - by Dan

  When you have a simple method, like for example sum(int x, int y), it is easy to write unit tests. You can check that method will sum correctly two sample integers, for example 2 + 3 should return 5, then you will check the same for some "extraordinary" numbers, for example negative values and zero. Each of these should be separate unit test, as a single unit test should contain single assert. What do you do when you have a complex input-output? Take a Xml parser for example. You can have a single method parse(String xml) that receives the String and returns a Dom object. You can write separate tests that will check that certain text node is parsed correctly, that attributes are parsed OK, that child node belongs to parent etc. For all these I can write a simple input, for example <root><child/></root> that will be used to check parent-child relationships between nodes and so on for the rest of expectations. Now, take a look at follwing Xml: <root> <child1 attribute11="attribute 11 value" attribute12="attribute 12 value">Text 1</child1> <child2 attribute21="attribute 21 value" attribute22="attribute 22 value">Text 2</child2> </root> In order to check that method worked correctly, I need to check many complex conditions, like that attribute11 and attribute12 belong to element1, that Text 1 belongs to child1 etc. I do not want to put more than one assert in my unit-test. How can I accomplish that?

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• Cakephp Search Plugin: DateTime Range

  - by Chris

  I am trying to search a model by dates using the CakePHP Search plugin The idea is: The user enters a date of a flight and the engine returns all flights within +- one day of that. My form: <?php echo $form->create('Flight', array( 'url' => array_merge(array('action' => 'find'), $this->params['pass']) )); echo $form->input('departure', array('div' => false, 'dateFormat' => 'DMY','timeFormat' => 'NONE')); echo $form->submit(__('Search', true), array('div' => false)); echo $form->end(); ?> My flight model: public $filterArgs = array( array('name' => 'departure', 'type' => 'expression', 'method' => 'makeRangeCondition', 'field' => 'ABS((TO_Days(Flight.departure))-( TO_Days(?))) < 2') ); The controller: public $presetVars = array( array('field' => 'departure', 'type' => 'expression') ); public function find() { $this->Prg->commonProcess(); $this->paginate['conditions'] = $this->Flight->parseCriteria($this->passedArgs); $this->set('flights', $this->paginate()); } When I try to search, the values for departure are packed in an array; Array ([departure] => Array ) And the filterArgs(...) function doesn't seem to understand this. What is the correct way to do this?

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• What is happening in Crockford's object creation technique?

  - by Chris Noe

  There are only 3 lines of code, and yet I'm having trouble fully grasping this: Object.create = function (o) { function F() {} F.prototype = o; return new F(); }; newObject = Object.create(oldObject); (from Prototypal Inheritance) 1) Object.create() starts out by creating an empty function called F. I'm thinking that a function is a kind of object. Where is this F object being stored? Globally I guess. 2) Next our oldObject, passed in as o, becomes the prototype of function F. Function (i.e., object) F now "inherits" from our oldObject, in the sense that name resolution will route through it. Good, but I'm curious what the default prototype is for an object, Object? Is that also true for a function-object? 3) Finally, F is instantiated and returned, becoming our newObject. Is the "new" operation strictly necessary here? Doesn't F already provide what we need, or is there a critical difference between function-objects and non-function-objects? Clearly it won't be possible to have a constructor function using this technique. What happens the next time Object.create() is called? Is global function F overwritten? Surely it is not reused, because that would alter previously configured objects. And what happens if multiple threads call Object.create(), is there any sort of synchronization to prevent race conditions on F?

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• Invoke Command When "ENTER" Key Is Pressed In XAML

  - by bitxwise

  I want to invoke a command when ENTER is pressed in a TextBox. Consider the following XAML: <UserControl ... xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity" ...> ... <TextBox> <i:Interaction.Triggers> <i:EventTrigger EventName="KeyUp"> <i:InvokeCommandAction Command="{Binding MyCommand}" CommandParameter="{Binding Text}" /> </i:EventTrigger> </i:Interaction.Triggers> </TextBox> ... </UserControl> and that MyCommand is as follows: public ICommand MyCommand { get { return new DelegateCommand<string>(MyCommandExecute); } } private void MyCommandExecute(string s) { ... } With the above, my command is invoked for every key press. How can I restrict the command to only invoke when the ENTER key is pressed? I understand that with Expression Blend I can use Conditions but those seem to be restricted to elements and can't consider event arguments. I have also come across SLEX which offers its own InvokeCommandAction implementation that is built on top of the Systems.Windows.Interactivity implementation and can do what I need. Another consideration is to write my own trigger, but I'm hoping there's a way to do it without using external toolkits.

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• Performance of Multiple Joins

  - by geeko

  Greetings Overflowers, I need to query against objects with many/complex spacial conditions. In relational databases that is translated to many joins (possibly 10+). I'm new to this business and wondering whether to go with MS SQL Server 2008 R2 or Oracle 11g or document-based solutions such as RavenDB or simply go with some spacial database (GIS)... Any thoughts ? Regards UPDATE: Thank you all for your answers. Would anybody opt for document/spatial databases ? My database would consist of tens of millions to few billion records. Mostly read-only. Almost no updates unless in case of mistakes in input. Overnight inserts and not that frequent. The join tables are predicted beforehand but the number of self joins (tables joining themselves multiple times) is not. Small pages of results from such queries are going to be viewed on an highly interactive website so response time is critical. Any predictions on how this can perform on MS SQL Server 2008 R2 or Oracle 11g ? I'm also concerned about boosting performance by adding more servers, which one scales better ? How about PostgresQL ?

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• How to test if a user has SELECTED a file to upload ?

  - by Tristan

  Hello, on a page, i have : if (!empty($_FILES['logo']['name'])) { $dossier = 'upload/'; $fichier = basename($_FILES['logo']['name']); $taille_maxi = 100000; $taille = filesize($_FILES['logo']['tmp_name']); $extensions = array('.png', '.jpg', '.jpeg'); $extension = strrchr($_FILES['logo']['name'], '.'); if(!in_array($extension, $extensions)) { $erreur = 'ERROR you must upload the right type'; } if($taille>$taille_maxi) { $erreur = 'too heavy'; } if(!empty($erreur)) { ....................... } The problem is, if the users wants to edit information WITHOUT uploading a LOGO, it raises an error : 'error you must upload the right type' So, if a user didn't put anything in the inputbox in order to upload it, i don't want to enter in these conditions test. i tested : if (!empty($_FILES['logo']['name']) and if (isset($_FILES['logo']['name']) but both doesn't seems to work. Any ideas? edit : maybe i wasn't so clear, i don't want to test if he uploaded a logo, i want to test IF he selected a file to upload, because right now, if he doesn't select a file to upload, php raises an error telling he must upload with the right format. thanks.

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• Ruby-on-Rails: Multiple has_many :through possible?

  - by williamjones

  Is it possible to have multiple has_many :through relationships that pass through each other in Rails? I received the suggestion to do so as a solution for another question I posted, but have been unable to get it to work. Friends are a cyclic association through a join table. The goal is to create a has_many :through for friends_comments, so I can take a User and do something like user.friends_comments to get all comments made by his friends in a single query. class User has_many :friendships has_many :friends, :through => :friendships, :conditions => "status = #{Friendship::FULL}" has_many :comments has_many :friends_comments, :through => :friends, :source => :comments end class Friendship < ActiveRecord::Base belongs_to :user belongs_to :friend, :class_name => "User", :foreign_key => "friend_id" end This looks great, and makes sense, but isn't working for me. This is the error I'm getting in relevant part when I try to access a user's friends_comments: ERROR: column users.user_id does not exist : SELECT "comments".* FROM "comments" INNER JOIN "users" ON "comments".user_id = "users".id WHERE (("users".user_id = 1) AND ((status = 2))) When I just enter user.friends, which works, this is the query it executes: : SELECT "users".* FROM "users" INNER JOIN "friendships" ON "users".id = "friendships".friend_id WHERE (("friendships".user_id = 1) AND ((status = 2))) So it seems like it's entirely forgetting about the original has_many through friendship relationship, and then is inappropriately trying to use the User class as a join table. Am I doing something wrong, or is this simply not possible?

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• Uploading multiple files asynchronously by blueimp jquery-fileupload

  - by Ryo

  I'm using jQuery File Upload library (http://github.com/blueimp/jQuery-File-Upload), and I've been stuck figuring out how to use the library satisfying the following conditions. The page has multiple file input fields surrounded by a form tag. Users can attach multiple files to each input field All files are sent to a server when the button is clicked, not when files are attached to the input fields. Upload is done asynchronously Say the page has 3 input fields with their name attributes being "file1[]", "file2[]" and "file3[]", the request payload should be like {file1: [ array of files on file1[] ], file2: [ array of files on file2[] ], ...} Here's jsFiddle, it's behaving weird so far in that it sends post request twice and the first one is cancelled. http://jsfiddle.net/BAQtG/24/ The core part of js code looks like this. $(document).ready(function(){ var filesList = [] var elem = $("form") file_upload = elem.fileupload({ formData:{extra:1}, autoUpload: false, fileInput: $("input:file"), }).on("fileuploadadd", function(e, data){ filesList.push(data.files[0]) }); $("button").click(function(){ file_upload.fileupload('send', {files:filesList} ) }) }) Anybody have idea how to get this to work? Updates Now thanks to @CBroe 's comment, the issue that request is sent twice is fixed. However the keys of request parameter is not correctly set. Here's updated jsFiddle. http://jsfiddle.net/BAQtG/27/

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• Am I using the getch() function from the ncurses library incorrectly?

  - by user1692446

  I am writing a Pacman game in c++ using the ncurses library, but I am not able to move the Pacman properly. I have used getch() to move it it up, down, left and right, but it only moves right and does not move anywhere else when I press any other key. This is a code snippet for moving up. I have written similar code with some conditions altered accordingly for moving left, right and down. int ch = getch(); if (ch == KEY_RIGHT) { int i,row,column; //getting position of cursor by getyx function for (i=column; i<=last_column; i+=2) { //time interval of 1 sec mvprintw(row,b,"<"); //print < in given (b,row) coordinates //time interval of 1 sec mvprintw(row,(b+1),"O"); //print "O" next to "<" int h = getch(); //to give the option for pressing another key if (h != KEY_RIGHT) //break current loop if another key is pressed { break; } } } if (condition) { //code to move left } Am I using getch() wrong, or is there something else I have to do?

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• Should I use a binary or a text file for storing protobuf messages?

  - by nbolton

  Using Google protobuf, I am saving my serialized messaged data to a file - in each file there are several messages. We have both C++ and Python versions of the code, so I need to use protobuf functions that are available in both languages. I have experimented with using SerializeToArray and SerializeAsString and there seems to be the following unfortunate conditions: SerializeToArray: As suggested in one answer, the best way to use this is to prefix each message with it's data size. This would work great for C++, but in Python it doesn't look like this is possible - am I wrong? SerializeAsString: This generates a serialized string equivalent to it's binary counterpart - which I can save to a file, but what happens if one of the characters in the serialization result is \n - how do we find line endings, or the ending of messages for that matter? Update: Please allow me to rephrase slightly. As I understand it, I cannot write binary data in C++ because then our Python application cannot read the data, since it can only parse string serialized messages. Should I then instead use SerializeAsString in both C++ and Python? If yes, then is it best practice to store such data in a text file rather than a binary file? My gut feeling is binary, but as you can see this doesn't look like an option.

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• webpart context.session is null

  - by tbischel

  I've been using the session array to store a state variable for my webpart... so I have a property like this: public INode RootNode { get { return this.Context.Session["RootNode"] as INode; } set { this.Context.Session["RootNode"] = value as object; } } This usually works fine. I've discovered that sometimes, the context.session variable will be null. I'd like to know what are the conditions that cause the session to be null in the first place, and whats the best way to persist my object when this happens? Can I just assign a new HttpSessionState object to the context, or does that screw things up? Edit: Ok, so its not just the session that is null... the whole context is screwed up. When the webpart enters the init, the context is fine... but when it reaches the dropbox selectedindexchange postback event (the dropbox contains node id's to use to set the rootnode variable), the context contains mostly null properties. also, it only seems to happen when certain id's are selected. This looks more like some kind of weird bug on my end than a problem with my understanding of the session.

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• mysql get table based on common column between two tables

  - by Zentdayn

  while trying to learn sql i came across "Learn SQL The Hard Way" and i started reading it. Everything was going fine then i thought ,as a way to practice, to make something like given example in the book (example consists in 3 tables pet,person,person_pet and the person_pet table 'links' pets to their owners). I made this: report table +----+-------------+ | id | content | +----+-------------+ | 1 | bank robbery| | 2 | invalid | | 3 | cat on tree | +----+-------------+ notes table +-----------+--------------------+ | report_id | content | +-----------+--------------------+ | 1 | they had guns | | 3 | cat was saved | +-----------+--------------------+ wanted result +-----------+--------------------+---------------+ | report_id | report_content | report_notes | +-----------+--------------------+---------------+ | 1 | bank robbery | they had guns | | 2 | invalid | null or '' | | 3 | cat on tree | cat was saved | +-----------+--------------------+---------------+ I tried a few combinations but no success. My first thought was SELECT report.id,report.content AS report_content,note.content AS note_content FROM report,note WHERE report.id = note.report_id but this only returns the ones that have a match (would not return the invalid report). after this i tried adding IF conditions but i just made it worse. My question is, is this something i will figure out after getting past basic sql or can this be done in simple way? Anyway i would appreciate any help, i pretty much lost with this. Thank you. EDIT: i have looked into related questions but havent yet found one that solves my problem. I probably need to look into other statements such as join or something to sort this out.

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• MySQL to PostreSQL and Named Scope

  - by Lowgain

  I've got a named scope for one of my models that works fine. The code is: named_scope :inbox_threads, lambda { |user| { :include => [:deletion_flags, :recipiences], :conditions => ["recipiences.user_id = ? AND deletion_flags.user_id IS NULL", user.id], :group => "msg_threads.id" }} This works fine on my local copy of the app with a MySQL database, but when I push my app to Heroku (which only uses PostgreSQL), I get the following error: ActiveRecord::StatementInvalid (PGError: ERROR: column "msg_threads.subject" must appear in the GROUP BY clause or be used in an aggregate function: SELECT "msg_threads"."id" AS t0_r0, "msg_threads"."subject" AS t0_r1, "msg_threads"."originator_id" AS t0_r2, "msg_thr eads"."created_at" AS t0_r3, "msg_threads"."updated_at" AS t0_r4, "msg_threads"."url_key" AS t0_r5, "deletion_flags"."id" AS t1_r0, "deletion_flags"."user_id" AS t1_r1, "deletion_flags"."msg_thread_id" AS t1_r2, "deletion_flags"."confirmed" AS t1_r3, "deletion_flags"."created_at" AS t1_r4, "deletion_flags"."updated_at" AS t1_r5, "recipiences"."id" AS t2_r0, "recipiences"."user_id" AS t2_r1, "recipiences"."msg_thread_id" AS t2_r2, "recipiences"."created_at" AS t2_r3, "recipien ces"."updated_at" AS t2_r4 FROM "msg_threads" LEFT OUTER JOIN "deletion_flags" ON deletion_flags.msg_thread_id = msg_threads.id LEFT OUTER JOIN "recipiences" ON recipiences.msg_thread_id = msg_threads.id WHERE (recipiences.user_id = 1 AND deletion_flags.user_id IS NULL) GROUP BY msg_threads.id) I'm not as familiar with the working of Postgres, so what would I need to add here to get this working? Thanks!

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• Rails Association Problem

  - by looloobs

  I am having trouble with this association. I need to get an array of the primaries that belong to the soldiers in a platoon. So once I get all the soldiers in a platoon: @company = Company.find_by_id(1) @platoons = @company.platoons <% @platoons.each do |p| %> <%= p.soldiers.primaries.find(:all,:conditions => ["relationship = ? AND contacted = ?", 'Spouse', 'Yes'])) %> <% end %> * So there is no method for primaries, I assume this is because I am trying to call an association on an array. Soldiers have a platoon_id but primaries do not, they only have the association to soldiers in that platoon. How do I do this? I need it to return an array of Primaries. Thanks in advance! class Soldier < ActiveRecord::Base belongs_to :company belongs_to :platoon has_many :primaries, :dependent => :destroy end class Platoon < ActiveRecord::Base belongs_to :company belongs_to :battalion has_many :soldiers end class Primary < ActiveRecord::Base belongs_to :soldier belongs_to :company end

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• Boost threading/mutexs, why does this work?

  - by Flamewires

  Code: #include <iostream> #include "stdafx.h" #include <boost/thread.hpp> #include <boost/thread/mutex.hpp> using namespace std; boost::mutex mut; double results[10]; void doubler(int x) { //boost::mutex::scoped_lock lck(mut); results[x] = x*2; } int _tmain(int argc, _TCHAR* argv[]) { boost::thread_group thds; for (int x = 10; x>0; x--) { boost::thread *Thread = new boost::thread(&doubler, x); thds.add_thread(Thread); } thds.join_all(); for (int x = 0; x<10; x++) { cout << results[x] << endl; } return 0; } Output: 0 2 4 6 8 10 12 14 16 18 Press any key to continue . . . So...my question is why does this work(as far as i can tell, i ran it about 20 times), producing the above output, even with the locking commented out? I thought the general idea was: in each thread: calculate 2*x copy results to CPU register(s) store calculation in correct part of array copy results back to main(shared) memory I would think that under all but perfect conditions this would result in some part of the results array having 0 values. Is it only copying the required double of the array to a cpu register? Or is it just too short of a calculation to get preempted before it writes the result back to ram? Thanks.

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• Access VBA question: Change the query being referenced by a function, depending on context

  - by Tara Amatista

  I have a custom function in Access2007 that hinges on grabbing data out of a specific query. It opens Outlook, creates a new email and populates the fields with specific addresses and data taken from the query ("DecisionEmail"). Now I want to make a different query ("RequestEmail") and have it populate the email with that data. So all I have to do is change this line: Set MailList = db.OpenRecordset("DecisionEmail") and that's where I get stumped. This is my desired result: If the user is on Form_Decision and clicks the button "Send email", "DecisionEmail" will get plugged into the function and that data will appear in the email. If the user on Form_SendRequest and clicks the button "Send email", "RequestEmail" will instead get plugged in. The reason that these are different queries is because they contain very different information that is smudged about in different ways. However, since it's just one little thing that needs to change in the function code, I don't think a brand new function is a good idea. My last resort would be to make a brand new function and use the Conditions field in the Macro interface to choose between them, but I have a feeling there's a more elegant solution possible. I have a vague notion of setting the query names as variables and using an If statement but I just don't have the mental vocabulary for thinking through this.

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• Updating UI objects in windows forms

  - by P a u l

  Pre .net I was using MFC, ON_UPDATE_COMMAND_UI, and the CCmdUI class to update the state of my windows UI. From the older MFC/Win32 reference: Typically, menu items and toolbar buttons have more than one state. For example, a menu item is grayed (dimmed) if it is unavailable in the present context. Menu items can also be checked or unchecked. A toolbar button can also be disabled if unavailable, or it can be checked. Who updates the state of these items as program conditions change? Logically, if a menu item generates a command that is handled by, say, a document, it makes sense to have the document update the menu item. The document probably contains the information on which the update is based. If a command has multiple user-interface objects (perhaps a menu item and a toolbar button), both are routed to the same handler function. This encapsulates your user-interface update code for all of the equivalent user-interface objects in a single place. The framework provides a convenient interface for automatically updating user-interface objects. You can choose to do the updating in some other way, but the interface provided is efficient and easy to use. What is the guidance for .net Windows Forms? I am using an Application.Idle handler in the main form but am not sure this is the best way to do this. About the time I put all my UI updates in the Idle event handler my app started to show some performance problems, and I don't have the metrics to track this down yet. Not sure if it's related.

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• does entity framework or mysql provider swallows timeout exceptions on enumeration of result?!

  - by Freddy Rios

  I'm trying to make sense of a situation I have using entity framework on .net 3.5 sp1 + MySQL 6.1.2.0 as the provider. It involves the following code: Response.Write("Products: " + plist.Count() + "<br />"); var total = 0; foreach (var p in plist) { //... some actions total++; //... other actions } Response.Write("Total Products Checked: " + total + "<br />"); Basically the total products is varying on each run, and it isn't matching the full total in plist. Its varies widely, from ~ 1/5th to half. There isn't any control flow code inside the foreach i.e. no break, continue, try/catch, conditions around total++, anything that could affect the count. As confirmation, there are other totals captured inside the loop related to the actions, and those match the lower and higher total runs. I don't find any reason to the above, other than something in entity framework or the mysql provider that causes it to end the foreach when retrieving an item. The body of the foreach can have some good variation in time, as the actions involve file & network access, my best shot at the time is that when it takes beyond certain threshold there is some type of timeout in the underlying framework/provider and instead of causing an exception it is silently reporting no more items for enumeration. Can anyone give some light in the above scenario and/or confirm if the entity framework/mysql provider has the above behavior?

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