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  • getting usb com port

    - by I__
    i have this function: private string GetUSBComPort() { string[] sPorts = SerialPort.GetPortNames(); foreach (string port in sPorts) { if (port != "COM1" && port != "COM4") { return port; } } return null; } this function is being called from form load: private void Form1_Load(object sender, EventArgs e) { serialPort1 = new SerialPort(GetUSBComPort()); if (serialPort1.IsOpen) { serialPort1.Close(); } serialPort1.Open(); //ThreadStart myThreadDelegate = new ThreadStart(ReceiveAndOutput); //Thread myThread = new Thread(myThreadDelegate); //myThread.Start(); this.serialPort1.DataReceived += new SerialDataReceivedEventHandler(sp_DataReceived); } the function is unfortunately returning null how do i get the com port to which my phone is attached to via USB?

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  • assignment makes pointer from integer without a cast

    - by mrblippy
    hi, i am trying to make a linked list and create some methods. but i am getting the error assignment makes pointer from integer without a cast. #include <stdio.h> #include <stdlib.h> #include "students.h" node_ptr create(void) { node_ptr students = (node_ptr) malloc(sizeof(struct node)); students->ID = 0; students->name = NULL; students->next = NULL; return students; } void insert_in_order(int n, node_ptr list) { node_ptr before = list; node_ptr new_node = (node_ptr) malloc(sizeof(struct node)); new_node->ID = n;//error is here i think while(before->next && (before->next->ID < n)) { before = before->next; } new_node->next = before->next; before->next = new_node; }

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  • PHP mysql_real_escape_string() returning `NULL`

    - by DavidYell
    I'm using PHP Version 5.1.6 and trying to escape a query string from my $_GET array. However my script is returning a NULL after it's escaped. It seems that mysql_escape_string() works fine, but it's deprecated, so I don't want to use it. Having checked over the phpinfo() the MySQL lib is all loaded fine from what I can see. Has anyone experienced this kind of thing before? $term = $_GET['q']; var_dump($term); // string(7) "richard" echo "<br />"; $sterm = mysql_real_escape_string($term, $db); var_dump($sterm); // NULL It's very strange to me, I can't imagine why this function wouldn't work.

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  • Specifying $(this).val() for two different elements (by class)

    - by Chaya Cooper
    What would be the correct syntax for specifying 2 elements by class to evaluate their values when they have different classes? This snippet adds and/or removes values from "increase_priority1" when the user has selected both a complaint and ranked the importance level of the issue, however when I added the 2nd element (".complaint select") to the If Statement it stopped working properly and only accepts input from the 2nd item (Waist) after the 1rst item (Shoulders) has been selected. I believe the problem is that it's unable to determine which ".complaint select" to use, but I haven't been able to figure out how to use (this) for the 2nd element, or another similar approach. The complete function includes apx. 20 similar pairs of If Statements to set & unset other elements, and a working example with 4 pairs is available at http://jsfiddle.net/chayacooper/vWLEn/168/ I'm trying to avoid using ID's because that becomes pretty cumbersome to do for 25 Select elements and each of their values (ID's were also problematic because it stopped working when I added a 2nd element to the If Statement for removing/unsetting a value) Javascript var $increase_priority1 = $(".increase_priority1"); // If value is "Shoulders", complaint was Shoulders too small (select name=Shoulders value=Too_small) and it was assigned a level 1 priority (select class="ranking shoulders" value=1). // var's for other issues and priority levels go here $(".ranking, .complaint select").change(function() { var name = $(this).data("name"); //get priority name if ($(".complaint select").val() === "Too_small" && $(this).val() == 1 && !$(this).data("increase_priority1")) { //rank is 1, and not yet added to priority list $("<option>", {text:name, val:name}).appendTo($increase_priority1); $(this).data("increase_priority1", true); //flag as a priority item } if ($(this).data("increase_priority1") && ($(this).val() != 1 || $(".complaint select").val() != "Too_small")) { //is in priority list, but now demoted $("option[value=" + name + "]", $increase_priority1).remove(); $(this).removeData("increase_priority1"); //no longer a priority item } // Similar If Statements to set & unset other elements go here }); HTML <div> <label>To Increase - 1rst Priority <select name="modify_increase_1rst[]" class="increase_priority1" multiple> </select></label> </div> <div> <span class="complaint"> <label>Shoulders</label> <select name=Shoulders> <option value="null">Select</option><option value="Too_small">Too Small</option><option value="Too_big">Too Big</option><option value="Too_expensive">Too expensive</option> </select> </span> <label>Ranking</label> <select name="importance_bother_shoulders" class="ranking shoulders" data-name="Shoulders"> <option value="Null">Select</option><option value="1">1</option><option value="2">2</option><option value="3">3</option><option value="4">4</option> <option value="5">5</option> </select> </div> <div> <span class="complaint"> <label>Waist</label> <select name=Waist> <option value="null">Select</option><option value="Too_small">Too Small</option><option value="Too_big">Too Big</option><option value="Too_expensive">Too expensive</option> </select> </span> <label>Ranking</label> <select name="importance_bother_waist" class="ranking waist" data-name="Waist"> <option value="Null">Select</option><option value="1">1</option><option value="2">2</option><option value="3">3</option><option value="4">4</option> <option value="5">5</option> </select> </div>

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  • Node.js Cron Job Messing with Date Object

    - by PazoozaTest Pazman
    I'm trying to schedule several cron jobs to generate serial numbers for different entities within my web app. However I am running into this problem, when I'm looping each table, it says it has something to do with date.js. I'm not doing anything with a date object ? Not at this stage anyway. A couple of guesses is that the cron object is doing a date thing in its code and is referencing date.js. I'm using date.js to get access to things like ISO date. for (t in config.generatorTables) { console.log("t = " + config.generatorTables[t] + "\n\n"); var ts3 = azure.createTableService(); var jobSerialNumbers = new cronJob({ //cronTime: '*/' + rndNumber + ' * * * * *', cronTime: '*/1 * * * * *', onTick: function () { //console.log(new Date() + " calling topUpSerialNumbers \n\n"); manageSerialNumbers.topUpSerialNumbers(config.generatorTables[t], function () { }); }, start: false, timeZone: "America/Los_Angeles" }); ts3.createTableIfNotExists(config.generatorTables[t], function (error) { if (error === null) { var query = azure.TableQuery .select() .from(config.generatorTables[t]) .where('PartitionKey eq ?', '0') ts3.queryEntities(query, function (error, serialNumberEntities) { if (error === null && serialNumberEntities.length == 0) { manageSerialNumbers.generateNewNumbers(config.maxNumber, config.serialNumberSize, config.generatorTables[t], function () { jobSerialNumbers.start(); }); } else jobSerialNumbers.start(); }); } }); } And this is the error message I'm getting when I examine the server.js.logs\0.txt file: C:\node\w\WebRole1\public\javascripts\date.js:56 onsole.log('isDST'); return this.toString().match(/(E|C|M|P)(S|D)T/)[2] == "D" ^ TypeError: Cannot read property '2' of null at Date.isDST (C:\node\w\WebRole1\public\javascripts\date.js:56:110) at Date.getTimezone (C:\node\w\WebRole1\public\javascripts\date.js:56:228) at Object._getNextDateFrom (C:\node\w\WebRole1\node_modules\cron\lib\cron.js:88:30) at Object.sendAt (C:\node\w\WebRole1\node_modules\cron\lib\cron.js:51:17) at Object.getTimeout (C:\node\w\WebRole1\node_modules\cron\lib\cron.js:58:30) at Object.start (C:\node\w\WebRole1\node_modules\cron\lib\cron.js:279:33) at C:\node\w\WebRole1\server.js:169:46 at Object.generateNewNumbers (C:\node\w\WebRole1\utils\manageSerialNumbers.js:106:5) at C:\node\w\WebRole1\server.js:168:45 at C:\node\w\WebRole1\node_modules\azure\lib\services\table\tableservice.js:485:7 I am using this line in my database.js file: require('../public/javascripts/date'); is that correct that I only have to do this once, because date.js is global? I.e. it has a bunch of prototypes (extensions) for the inbuilt date object. Within manageSerialNumbers.js I am just doing a callback, their is no code executing as I've commented it all out, but still receiving this error. Any help or advice would be appreciated.

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  • Stop running this script, IE7 using PHP

    - by Jomel Dicen
    I incorporate javascript in my PHP program: Try to check my codes. It loops depend on the number of records in database. for instance: $counter = 0; foreach($row_value as $data): echo $this->javascript($counter, $data->exrate, $data->tab); endforeach; private function javascript($counter=NULL, $exrate=NULL, $tab=NULL){ $js = " <script type='text/javascript'> $(function () { var textBox0 = $('input:text[id$=quantity{$counter}]').keyup(foo); var textBox1 = $('input:text[id$=mc{$counter}]').keyup(foo); var textBox2 = $('input:text[id$=lc{$counter}]').keyup(foo); function foo() { var value0 = textBox0.val(); var value1 = textBox1.val(); var value2 = textBox2.val(); var sum = add(value1, value2) * (value0 * {$exrate}); $('input:text[id$=result{$counter}]').val(parseFloat(sum).toFixed(2)); // Compute Total Quantity var qtotal = 0; $('.quantity{$tab}').each(function() { qtotal += Number($(this).val()); }); $('#tquantity{$tab}').text(qtotal); // Compute MC UNIT var mctotal = 0; $('.mc{$tab}').each(function() { mctotal += Number($(this).val()); }); $('#tmc{$tab}').text(mctotal); // Compute LC UNIT var lctotal = 0; $('.lc{$tab}').each(function() { lctotal += Number($(this).val()); }); $('#tlc{$tab}').text(lctotal); // Compute Result var result = 0; $('.result{$tab}').each(function() { result += Number($(this).val()); }); $('#tresult{$tab}').text(result); } function add() { var sum = 0; for (var i = 0, j = arguments.length; i < j; i++) { if (IsNumeric(arguments[i])) { sum += parseFloat(arguments[i]); } } return sum; } function IsNumeric(input) { return (input - 0) == input && input.length > 0; } }); </script> "; return $js; } When I running this on IE this message is always annoying me " Stop running this script? A script on this page is causing your web browser to run slowly. If it continues to run, your computer might become unresponsive." but in firefox it's functioning well.

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  • AudioTrack skipping after pause and resume

    - by Markus Drösser
    Hi, here is the problem. I play a wav file that i recorded earlier without problems. but when i call audiotrack.pause() and audiotrack.start() again after some waiting, it skips some frames of the file. why is that? here is my play listener // Start playback audioTrack.setPlaybackPositionUpdateListener(new OnPlaybackPositionUpdateListener() { @Override public void onPeriodicNotification(AudioTrack track) { try { if(ramfile!=null && ramfile.read(buffer)==-1) { audioTrack.release(); audioTrack = null; ramfile.close(); playing=false; } else { audioTrack.write(buffer, 0, buffer.length); } } catch (IOException e) { try { ramfile.close(); playing=false; } catch (IOException e1) { } } } @Override public void onMarkerReached(AudioTrack track) { playing=false; track.release(); } });

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  • How does lock(syncRoot) make sense on a static method?

    - by Rising Star
    The following code is excerpted from the (Windows Identity Foundation SDK) template that MS uses to create a new Security Token Service Web Site. public static CustomSecurityTokenServiceConfiguration Current { get { HttpApplicationState httpAppState = HttpContext.Current.Application; CustomSecurityTokenServiceConfiguration customConfiguration = httpAppState.Get( CustomSecurityTokenServiceConfigurationKey ) as CustomSecurityTokenServiceConfiguration; if ( customConfiguration == null ) { lock ( syncRoot ) { customConfiguration = httpAppState.Get( CustomSecurityTokenServiceConfigurationKey ) as CustomSecurityTokenServiceConfiguration; if ( customConfiguration == null ) { customConfiguration = new CustomSecurityTokenServiceConfiguration(); httpAppState.Add( CustomSecurityTokenServiceConfigurationKey, customConfiguration ); } } } return customConfiguration; } } I'm relatively new to multi-threaded programming. I assume that the reason for the lock statement is to make this code thread-safe in the event that two web requests arrive at the web site at the same time. However, I would have thought that using lock (syncRoot) would not make sense because syncRoot refers to the current instance that this method is operating on... but this is a static method? How does this make sense?

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  • Data structure name: combination array/linked list

    - by me_and
    I have come up with a data structure that combines some of the advantages of linked lists with some of the advantages of fixed-size arrays. It seems very obvious to me, and so I'd expect someone to have thought of it and named it already. Does anyone know what this is called: Take a small fixed-size array. If the number of elements you want to put in your array is greater than the size of the array, add a new array and whatever pointers you like between the old and the new. Thus you have: Static array ————————————————————————— |1|2|3|4|5|6|7|8|9|a|b|c| ————————————————————————— Linked list ———— ———— ———— ———— ———— |1|*->|2|*->|3|*->|4|*->|5|*->NULL ———— ———— ———— ———— ———— My thing: ———————————— ———————————— |1|2|3|4|5|*->|6|7|8|9|a|*->NULL ———————————— ————————————

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  • Why are some programs writing on stderr instead of stdout their output?

    - by Zagorax
    I've recently added to my .bashrc file an ssh-add command. I found that ssh-add $HOME/.ssh/id_rsa_github > /dev/null results on a message "identity added and something else" every time I open a shell. While ssh-add $HOME/.ssh/id_rsa_github > /dev/null 2>&1 did the trick and my shell is now 'clean'. Reading on internet, I found that other command do it, (for example time). Could you please explain why it's done?

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  • How can I obtain the IP address of my server program?

    - by Dr Dork
    Hello! This question is related to another question I just posted. I'm prepping for a simple work project and am trying to familiarize myself with the basics of socket programming in a Unix dev environment. At this point, I have some basic server side code and client side code setup to communicate. Currently, my client code successfully connects to the server code and the server code sends it a test message, then both quit out. Perfect! That's exactly what I wanted to accomplish. Now I'm playing around with the functions used to obtain info about the two environments (server and client). I'd like to obtain my server program's IP address. Here's the code I currently have to do this, but it's not working... int sockfd; unsigned int len; socklen_t sin_size; char msg[]="test message"; char buf[MAXLEN]; int st, rv; struct addrinfo hints, *serverinfo, *p; struct sockaddr_storage client; char s[INET6_ADDRSTRLEN]; char ip[INET6_ADDRSTRLEN]; //zero struct memset(&hints,0,sizeof(hints)); hints.ai_family = AF_UNSPEC; hints.ai_socktype = SOCK_STREAM; hints.ai_flags = AI_PASSIVE; //get the server info if((rv = getaddrinfo(NULL, SERVERPORT, &hints, &serverinfo ) != 0)){ perror("getaddrinfo"); exit(-1); } // loop through all the results and bind to the first we can for( p = serverinfo; p != NULL; p = p->ai_next) { //Setup the socket if( (sockfd = socket( p->ai_family, p->ai_socktype, p->ai_protocol )) == -1 ) { perror("socket"); continue; } //Associate a socket id with an address to which other processes can connect if(bind(sockfd, p->ai_addr, p->ai_addrlen) == -1){ close(sockfd); perror("bind"); continue; } break; } if( p == NULL ){ perror("Fail to bind"); } inet_ntop(p->ai_family, get_in_addr((struct sockaddr *)p->ai_addr), s, sizeof(s)); printf("Server has TCP Port %s and IP Address %s\n", SERVERPORT, s); and the output for the IP is always empty... server has TCP Port 21412 and IP Address :: any ideas for what I'm missing? thanks in advance for your help! this stuff is really complicated at first.

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  • Running out of memory when getting a bitmap from a server?

    - by ikky
    Hi! I'm making an application which uses MANY images. The application gets the images from a server, and downloads them one at a time. After many images the creation of a bitmap returns an exception, but i don't know how to solve this. Here is my function for downloading the images: public static Bitmap getImageFromWholeURL(String sURL) { HttpWebRequest myRequest = (HttpWebRequest)WebRequest.Create(sURL); myRequest.Method = "GET"; // If it does not exist anything on the url, then return null try { HttpWebResponse myResponse = (HttpWebResponse)myRequest.GetResponse(); System.Drawing.Bitmap bmp = new System.Drawing.Bitmap(myResponse.GetResponseStream()); myResponse.Close(); return bmp; } catch (Exception e) { return null; } } Can anyone help me out here? Thanks in advance!

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  • Will lock() statement block all threads in the proccess/appdomain?

    - by MikeJ
    Maybe the question sounds silly, but I don't understand 'something about threads and locking and I would like to get a confirmation (here's why I ask). So, if I have 10 servers and 10 request in the same time come to each server, that's 100 request across the farm. Without locking, thats 100 request to the database. If I do something like this: private static readonly object myLockHolder = new object(); if (Cache[key] == null) { lock(myLockHolder) { if (Cache[key] == null) { Cache[key] = LengthyDatabaseCall(); } } } How many database requests will I do? 10? 100? Or as much as I have threads?

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  • Access sub-class object

    - by Amit
    There is a main class containing 2 sub-class(with some prop). If I create an obj of main class, will have access to sub-Class as well b/c we have property defined in main class. Is thr any way where I pass Main class.SubClass name then it will return that object only ? can we use indexer ? MainClass obj = new MainClass(); obj.SubClass1 or obj.SubClass2 ??? Thanks in adv... class MainClass { SubClass1 objSubclass1 = null; SubClass2 objSubclass2 = null; public MainClass() { objSubclass1 = new SubClass1(); objSubclass2 = new SubClass2(); } public SubClass1 SubClass1 {get {return objSubclass1;} } public SubClass2 SubClass2 {get {return objSubclass2;} } } Class SubClass1 { Some properties here... } Class SubClass2 { Some properties here... }

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  • where should this check logic go?

    - by Benny
    I have a function that draw a string on graphics: private void DrawSmallImage(Graphics g) { if (this.SmallImage == null) return; var smallPicHeight = this.Height / 5; var x = this.ClientSize.Width - smallPicHeight; var y = this.ClientSize.Height - smallPicHeight; g.DrawImage(this.SmallImage, x, y, smallPicHeight, smallPicHeight); } the check if (this.SmallImage == null) return; should be in the function DrawSmallImage or should be in the caller? which is better?

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  • 1) PasswordResets emails user when requesting password reset

    - by Surge Pedroza
    I've been trying to add a password reset for users that forget their password. The users clicks on forgot password? on sign up page. Then the user types their email and clicks reset password, which creates a token and sends an email with a link to reset their password. For the most part, it was working well, and then it suddenly stopped working. When a user clicks password reset, it brings up the error message: Password cant be blank, password is too short(6 min) Ran into this error in video 275 How I Test. on 11:20 Failure/Error: click_button "Reset Password" ActiveRecord::RecordInvalid: Validation failed: Password can't be blank, Password is too short (minimum is 6 characters), Password confirmation can't be blank # ./app/models/user.rb:30:in send_password_reset' # ./app/controllers/password_resets_controller.rb:7:increate' # (eval):2:in click_button' # ./spec/requests/password_resets_spec.rb:9:inblock (2 levels) in ' Finished in 13.66 seconds 95 examples, 1 failure This is some of the code being used. user.rb # == Schema Information # # Table name: users # # id :integer not null, primary key # name :string(255) # email :string(255) # created_at :datetime not null # updated_at :datetime not null # class User < ActiveRecord::Base attr_accessible :name, :email, :password, :password_confirmation has_secure_password before_save { |user| user.email = email.downcase } before_save :create_remember_token validates :name, presence: true, length: { maximum: 50 } VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i validates :email, presence: true, format: { with: VALID_EMAIL_REGEX }, uniqueness: { case_sensitive: false } validates :password, presence: true, length: { minimum: 6 } validates :password_confirmation, presence: true def send_password_reset generate_token(:password_reset_token) self.password_reset_sent_at = Time.zone.now save! UserMailer.password_reset(self).deliver end def generate_token(column) begin self[column] = SecureRandom.urlsafe_base64 end while User.exists?(column => self[column]) end def self.search(search) if search find(:all, :conditions => ['name LIKE ?', "%#{search}%"]) else find(:all) end end private def create_remember_token self.remember_token = SecureRandom.urlsafe_base64 end end password_resets_controller.rb class PasswordResetsController < ApplicationController def new end def create user = User.find_by_email(params[:email]) user.send_password_reset redirect_to root_url, :notice => "Email sent with password reset instructions." end def edit @user = User.find_by_password_reset_token!(params[:id]) end end new.html.erb <h1>Reset Password</h1> <%= form_tag password_resets_path, :method => :post do %> <div class="field"> <%= label_tag :email %> <%= text_field_tag :email, params[:email] %> </div> <div class="actions"><%= submit_tag "Reset Password" %></div> <% end %>

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  • Apply CSS class to invalid controls on web form

    - by user137639
    I need to apply a css class to invalid controls on a web form. I'd like to make it a resusable class. This is what I have so far: public class Validation { public static void ApplyInvalidClass(Page page, string className) { foreach (System.Web.UI.WebControls.BaseValidator bv in page.Validators) { if (!bv.IsValid) { Control ctrl = page.FindControl(bv.ControlToValidate); if (ctrl != null) { if (ctrl is TextBox) { TextBox txt = ctrl as TextBox; txt.CssClass = "invalid"; } if (ctrl is DropDownList) { DropDownList ddl = ctrl as DropDownList; ddl.CssClass = "invalid"; } if (ctrl is CheckBox) { CheckBox cb = ctrl as CheckBox; cb.CssClass = "invalid"; } if (ctrl is HtmlGenericControl) { HtmlGenericControl html = ctrl as HtmlGenericControl; html.Attributes.Add("class", className); } } } } } } The problem is what I call this on a .Net user control, I guess because I'm passing in Page, page.FindControl(bv.ControlToValidate) is always null. Is there a better way to do this?

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  • Problem intialising 2D array

    - by TeeJay
    Ok, so I have a 2D Array that is initialised with values from a file (format: x y z). My file reads in the values correctly but when adding the z value to the matrix/2DArray, I run into a segfault and I have no idea why. It is possibly incorrect use of pointers? I still don't quite have the hang of them yet. This is my intialiser, works fine, even intialises all "z" values to 0. int** make2DArray(int rows, int columns) { int** newArray; newArray = (int**)malloc(rows*sizeof(int*)); if (newArray == NULL) { printf("out of memory for newArray.\n"); } for (int i = 0; i < rows; i++) { newArray[i] = (int*)malloc(columns*sizeof(int)); if (newArray[i] == NULL) { printf("out of memory for newArray[%d].\n", i); } } //intialise all values to 0 for (int i = 0; i < rows; i++) { for (int j = 0; j < columns; j++) { newArray[i][j] = 0; } } return newArray; } This is how I call the initialiser (and problem function). int** map = make2DArray(rows, columns); fillMatrix(&map, mapFile); And this is the problem code. void fillMatrix(int*** inMatrix, FILE* inFile) { int x, y, z; char line[100]; while(fgets(line, sizeof(line), inFile) != NULL) { sscanf(line, "%d %d %d", &x, &y, &z); *inMatrix[x][y] = z; } } From what I can gather through the use of ddd, the problem comes when y gets to 47. The map file has a max "x" value of 47 and a max "y" value of 63, I'm pretty sure I haven't got the order mixed up, so I don't know why the program is segfault-ing? I'm sure it's some newbie mistake...

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  • SQL Server concurrency and generated sequence

    - by Goyuix
    I need a sequence of numbers for an application, and I am hoping to leverage the abilities of SQL Server to do it. I have created the following table and procedure (in SQL Server 2005): CREATE TABLE sequences ( seq_name varchar(50) NOT NULL, seq_value int NOT NULL ) CREATE PROCEDURE nextval @seq_name varchar(50) AS BEGIN DECLARE @seq_value INT SET @seq_value = -1 UPDATE sequences SET @seq_value = seq_value = seq_value + 1 WHERE seq_name = @seq_name RETURN @seq_value END I am a little concerned that without locking the table/row another request could happen concurrently and end up returning the same number to another thread or client. This would be very bad obviously. Is this design safe in this regard? Is there something I can add that would add the necessary locking to make it safe? Note: I am aware of IDENTITY inserts in SQL Server - and that is not what I am looking for this in particular case. Specifically, I don't want to be inserting/deleting rows. This is basically to have a central table that manages the sequential number generator for a bunch of sequences.

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  • Rails create_table query

    - by Steve
    Hi, I am a beginner in Rails. In the following code,there is an id which is set as false. What's the meaning of it? class CreateCoursesStudents < ActiveRecord::Migration def self.up create_table :courses_students, :id => false do |t| t.integer :course_id, :null => false t.integer :student_id, :null => false end # Add index to speed up looking up the connection, and ensure # we only enrol a student into each course once add_index :courses_students, [:course_id, :student_id], :unique => true end def self.down remove_index :courses_students, :column => [:course_id, :student_id] drop_table :courses_students end end Thanks

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  • c# 4.0 - best way to refactor a block of "If (something is Type) {}" statements?

    - by Andrew Johns
    I've got some code that looks like this, public void ResetControls(Control controlOnPage) { if (controlOnPage is TextBox) { ResetTextBoxControl(controlOnPage); } if (controlOnPage is MediaPicker) { ((MediaPicker)controlOnPage).Media = null; } if (controlOnPage is RelatedContentPicker) { ((RelatedContentPicker)controlOnPage).RelatedContentCollection = null; } ... ... foreach (Control child in controlOnPage.Controls) { ResetControls(child); } } The idea behind it is that I can pass a page to the method and it'll recursively reset all the controls on it to their default states - in the case of MediaPicker and RelatedContentPicker, these are user controls that I've created. FXCop warns me "Do Not Cast Unnecessarily" for this code - but I'm unsure how to rewrite it to make it better. Any ideas?

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  • Is there some way to assume @Nullable as default? (using FindBugs or any other free tool).

    - by alex2k8
    Consider such code public void m1(String text) { if(text == null) text = "<empty>"; System.out.println(text.toLowerCase()); } And this is a buggy version: public void m1(String text) { System.out.println(text.toLowerCase()); } If null value passed, the NullPointerException may be thrown. I would like the static-analysis tool (e.g. FindBugs) to report this issue. Unsuccessfully the FindBugs (at least by default) requires me to specify @Nullable annotation explicitly. public void m1(@Nullable String text) { System.out.println(text.toLowerCase()); // FindBugs: text must be nonnull but is marked as nullable } The problem is that if I forget to annotate it, the bug will be missed!!! How can I make the FindBugs (or any other free tool) to assume @Nullable by default?

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  • How to import datarow from one dataset to another?

    - by Disciple
    Hi, I want to copy the row to the new dataset if the previous value in second column isn't the same as the current one (i.e this dataset should have rows with unique values): DataTable tbl = new DataTable(); DataTable tmpTable = ds.Tables[0]; for( var rowIndex = 0; rowIndex < ds.Tables[0].Rows.Count; rowIndex++ ) { object value = null; foreach (DataRow x in tbl.Rows) { if (ds.Tables[0].Rows[rowIndex][1] == x[1]) { value = ds.Tables[0].Rows[rowIndex][1]; break; } } // value already exists if (value == null) { tbl.ImportRow(ds.Tables[0].Rows[rowIndex]); } } How to do this correctly? Maybe one loop instead 2?

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  • c# How to make linq master detail query for 0..n relationship?

    - by JK
    Given a classic DB structure of Orders has zero or more OrderLines and OrderLine has exactly one Product, how do I write a linq query to express this? The output would be OrderNumber - OrderLine - Product Name Order-1 null null // (this order has no lines) Order-2 1 Red widget I tried this query but is not getting the orders with no lines var model = (from po in Orders from line in po.OrderLines select new { OrderNumber = po.Id, OrderLine = line.LineNumber, ProductName = line.Product.ProductDescription, } ) I think that the 2nd from is limiting the query to only those that have OrderLines, but I dont know another way to express it. LINQ is very non-obvious if you ask me!

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