Search Results

Search found 17924 results on 717 pages for 'z order'.

Page 596/717 | < Previous Page | 592 593 594 595 596 597 598 599 600 601 602 603  | Next Page >

  • Rails: include index with fields_for form helper

    - by Patrick Oscity
    i'm trying to build two models from one form by using the fields_for method. my code looks like this: <% for scale in @event.scales %> <% f.fields_for "scale[]", scale do |scale_form| %> <p> Scale<br /> <%= scale_form.label :name %> <%= scale_form.text_field :name %> <%= scale_form.label :price %> <%= scale_form.text_field :price %> </p> <% end %> <% end %> but unfortunately the output html is missing the id's of the scales: <p> Scale<br /> <label for="event_scale__name">Name</label> <input id="event_scale__name" name="event[scale][][name]" size="30" type="text" /> <label for="event_scale__price">Price</label> <input id="event_scale__price" name="event[scale][][price]" size="30" type="text" /> </p> ... here's the corresponding controller and model: class EventsController < ApplicationController ... def new @event = Event.new @providers = Provider.find(:all, :order => :name) 3.times { @event.scales.build } respond_to do |format| format.html end end ... end class Event < ActiveRecord::Base has_many :scales ... end what am i doing wrong?

    Read the article

  • Using a join with three tables when a field might be null

    - by John
    Hello, The code below works great. It combines data from two MySQL tables. I would like to modify it by pulling in some data from a third MySQL table called "comment." In the HTML table below, "title" is a field in the MySQL table "submission." Every "title" has a corresponding "submissionid" field. The field "submissionid" is also found in the "comment" MySQL table. In the HTML table below, I would like "countComments" to equal the number of times a field called "commentid" appears in the MySQL table "comment" for any given "submissionid," where the "submissionid" is the same in both the "submission" and "comment" tables, and where the "submissionid" corresponds to the "title" being used. Here's the catch: if there is no row in the MySQL table "comment" that corresponds with the "submissionid" being used for "table", I would like "countComments" to equal to zero. How can I do this? Thanks in advance, John $sqlStr = "SELECT s.loginid, s.title, s.url, s.displayurl, l.username FROM submission AS s, login AS l WHERE s.loginid = l.loginid ORDER BY s.datesubmitted DESC LIMIT 10"; $result = mysql_query($sqlStr); $arr = array(); echo "<table class=\"samplesrec\">"; while ($row = mysql_fetch_array($result)) { echo '<tr>'; echo '<td class="sitename1"><a href="http://www.'.$row["url"].'">'.$row["title"].'</a></td>'; echo '</tr>'; echo '<tr>'; echo '<td class="sitename2"><a href="http://www...com/sandbox/members/index.php?profile='.$row["username"].'">'.$row["username"].'</a><a href="http://www...com/sandbox/comments/index.php?submission='.$row["title"].'">'.$row["countComments"].'</a></td>'; echo '</tr>'; } echo "</table>";

    Read the article

  • Android XML Preference issue. Can't make it persistent

    - by Budius
    I have a very simple activity just to show the preference fragment: public class PreferencesActivity extends Activity { Fragment frag = null; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); FragmentTransaction ft = getFragmentManager().beginTransaction(); if (frag == null) { // If not, instantiate and add it to the activity frag = new PrefsFragment(); ft.add(android.R.id.content, frag, frag.getClass().getName()); } else { // If it exists, simply attach it in order to show it ft.attach(frag); } ft.commit(); } private static class PrefsFragment extends PreferenceFragment { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); addPreferencesFromResource(R.xml.preferences); } } } and preferences.xml with persistent to true: <?xml version="1.0" encoding="utf-8"?> <PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android" android:enabled="true" android:persistent="true" android:title="@string/settings" > <EditTextPreference android:dialogTitle="@string/dialog_ip" android:negativeButtonText="@android:string/cancel" android:persistent="true" android:positiveButtonText="@android:string/ok" android:title="@string/ip" /> </PreferenceScreen> if I open the EditTextPreference, write something, close the dialog and open it again. The value is still there. But that's it... if I click the Back button, and enter the again on the preferences screen, I already lost what was written. If you exit the application also doesn't save. Am I missing something here? Running on: Android 4.0.3 Asus TF300

    Read the article

  • Not able to play videos (from youtube) in WebView

    - by user1205193
    I am using a webview to display a video (could be from youtube or vimeo) in my app. In order to not load the video webpages in the default Android Browser, I am also extending the WebViewClient so I can override the shouldOverrideUrlLoading method. This way the video webpage loads successfully in the WebView. However, when I click on the embedded video on the WebView, it does not play. If I do not override the shouldOverrideUrlLoading method, and let the video webpages load in the default Android browser, the videos work just fine. Any ideas why the videos are not working in the WebView? Also, the main reason why I overrode the shouldOverrideUrlLoading method is because if I do not do that, then when I exit the Android browser to come back to my activity (by hitting the back button on the phone), I see a white screen. Upon hitting the back button twice, I am able to get back to my Activity. I am using the emulator to do this test. Here is my code: public class YoutubeLink extends Activity { WebView myWebView; String video_url; private class HelloWebViewClient extends WebViewClient { @Override public boolean shouldOverrideUrlLoading(WebView view, String url) { view.loadUrl(url); return true; } } @Override protected void onCreate(Bundle savedInstanceState) { // TODO Auto-generated method stub super.onCreate(savedInstanceState); setContentView(R.layout.youtubelink); //Retrieving data from ListSample.java Bundle extras = getIntent().getExtras(); if(extras !=null) { video_url = extras.getString("video_url"); Log.d("inside YoutubeLink.java", video_url); } myWebView = (WebView) findViewById(R.id.web); myWebView.getSettings().setJavaScriptEnabled(true); myWebView.setWebViewClient(new HelloWebViewClient()); myWebView.loadUrl(video_url); } @Override public boolean onKeyDown(int keyCode, KeyEvent event) { if ((keyCode == KeyEvent.KEYCODE_BACK) && myWebView.canGoBack()) { myWebView.goBack(); return true; } return super.onKeyDown(keyCode, event); }}

    Read the article

  • Python Loop for mysql statement

    - by user552974
    Hi, I have a project that i need to compile number of cities in each state and make an insert statement for mysql database. I think the easiest way to do it is via python but since i m a complete noob i would like to reach out all the python gurus here. Here is what the input looks like. Example below is for Florida. cities = ['Boca Raton', 'Boynton Beach', 'Bradenton', 'Cape Coral', 'Deltona'] and this what the output should be. INSERT INTO `oc_locations` (`idLocation`, `name`, `idLocationParent`, `friendlyName`) VALUES (1, 'Florida', 0, 'Florida'), (2, 'Boca Raton', 1, 'Boca Raton'), (3, 'Boynton Beach', 1, 'Boynton Beach'), (4, 'Bradenton', 1, 'Bradenton'), (5, 'Cape Coral', 1, 'Cape Coral'), (6, 'Deltona', 1, 'Deltona'), If you look at carefully the "idLocationParent" for "Florida" value is "0" so which means it is a top level value. This will be done for 50 states so ability to plug the state name into the mysql statement would be icing on the cake if there is a easy way to do it. Also alphabetical order and auto increment for the idLocation would be great. Here is an example of what i m trying to achieve concatenation is the part i need to figure out. for city in cities: print (1, 'city', 0, 'city'), city

    Read the article

  • When is the reintegrate option really necessary?

    - by Tor Hovland
    If you always sync a feature branch before you merge it back, why do you really have to use the --reintegrate option? The Subversion book says: When merging your branch back to the trunk, however, the underlying mathematics is quite different. Your feature branch is now a mishmosh of both duplicated trunk changes and private branch changes, so there's no simple contiguous range of revisions to copy over. By specifying the --reintegrate option, you're asking Subversion to carefully replicate only those changes unique to your branch. (And in fact, it does this by comparing the latest trunk tree with the latest branch tree: the resulting difference is exactly your branch changes!) So the --reintegrate option only merges the changes that are unique to the feature branch. But if you always sync before merge (which is a recommended practice, in order to deal with any conflicts on the feature branch), then the only changes between the branches are the changes that are unique to the feature branch, right? And if Subversion tries to merge code that is already on the target branch, it will just do nothing, right? In this blog post, Mark Phippard writes: http://blogs.open.collab.net/svn/2008/07/subversion-merg.html If we include those synched revisions, then we merge back changes that already exist in trunk. This yields unnecessary and confusing conflicts. Can somebody give me an example of when dropping reintegrate gives me unnecessary conflicts?

    Read the article

  • Apache console accesses network drives, service does not?

    - by danspants
    I have an apache 2.2 server running Django. We have a network drive T: which we need constant access to within our Django app. When running Apache as a service, we cannot access this drive, as far as any django code is concerned the drive does not exist. If I add... <Directory "t:/"> Options Indexes FollowSymLinks MultiViews AllowOverride None Order allow,deny allow from all </Directory> to the httpd.conf file the service no longer runs, but I can start apache as a console and it works fine, Django can find the network drive and all is well. Why is there a difference between the console and the service? Should there be a difference? I have the service using my own log on so in theory it should have the same access as I do. I'm keen to keep it running as a service as it's far less obtrusive when I'm working on the server (unless there's a way to hide the console?). Any help would be most appreciated.

    Read the article

  • How to stop the submission of the form using JQUERY?

    - by Param-Ganak
    Hello frineds! I have a form which have many check boxes in it. User will check one or many checkboxes and click on Delete button which is actually submit button then the respective records for selected check boxes are get deleted. Required operation steps are as follows:- When user selects one or more checkboxes and clicks the submit button then a JQUERY code is get executed in which It should checks that if any check box is selected; if not; then is displays alert message and do not submit the form. If it founds that one or more checkboxes are selected it should ask user for his/her confirmation using confirm alert box about the confirmation of deletion. If user press YES button on confirm box then it should submit the form using javascript submit statement. If user pressed the NO button then it should unchecks the checked selected checkboxes and should not submit the form. This is the JQUERY code I had written. $(document).ready(function (){ $("#id_delete").click(function(){ var temp=$("#id_frm input:checkbox:checked"); var len=temp.length; if(len==0) { alert("Please select the order."); } else { if(confirm("Are you sure to delete the selected orders.")) { $("#id_frm").submit(); } else { temp.checked=false; } } }); }); Problems: This code is not working properly. Here 1. It submits form when there is no check box is selected. 2. It submits the form when user press NO button on confirmation dialog box. Please guide me friends in this problem.

    Read the article

  • How does one force construction of a global object in a statically linked library? [MSVC9]

    - by Peter C O Johansson
    I have a global list of function pointers. This list should be populated at startup. Order is not important and there are no dependencies that would complicate static initialization. To facilitate this, I've written a class that adds a single entry to this list in its constructor, and scatter global instances of this class via a macro where necessary. One of the primary goals of this approach is to remove the need for explicitly referencing every instance of this class externally, instead allowing each file that needs to register something in the list to do it independently. Nice and clean. However, when placing these objects in a static library, the linker discards (or rather never links in) these units because no code in them is explicitly referenced. Explicitly referencing symbols in the compilation units would be counterproductive, directly contradicting one of the main goals of the approach. For the same reason, /INCLUDE is not an acceptable option, and /OPT:NOREF is not actually related to this problem. Metrowerks has a __declspec directive for it, GCC has -force_load, but I cannot find any equivalent for MSVC.

    Read the article

  • How to catch non exist requested URL in Java servlet ?

    - by Frank
    My objects are stored online in two different places : <1 On my nmjava.com site, where I can put them in a directory called "Dir_My_App/Dir_ABC/" <2 On Google App Engine datastore When my Java app runs it checks both places for the objects, I designed the app so that it tries to get an object from a Url, it doesn't care whether it's an object in a directory or an object returned by a servlet. My_Object Get_Object(String Site_Url,String Object_Path) { ... get object by the name of Object_Path from the Site_Url ... } Now the request Url for my web site nmjava.com might look like this : http://nmjava.com/Dir_My_App/Dir_ABC/My_Obj_123 [ In a directory ] Or in the case of Google App Engine servlet : http://nm-java.appspot.com/Check_License/Dir_My_App/Dir_ABC/My_Obj_123 [ Non exist ] The "Object_Path" was generated by my app automatically. It can now get the object from my site by the above method like this : My_Object Get_Object("http://nmjava.com","/Dir_My_App/Dir_ABC/My_Obj_123"); In the Google App Engine, my servlet is running and ready to serve the object, if the request comes in correctly, but since I don't want to design my app to know whether the object is in one site's directory or in other site's datastore, I need to design the servlet to catch the non exist Url, such as the one above, and be able to make a call : My_Object Get_Object("http://nm-java.appspot.com/Check_License","/Dir_My_App/Dir_ABC/My_Obj_123"); So my question is : When a request comes into the servlet with a non exist Url, how should it catch it and analyze the url in order to respond properly, in my case it should know that : http://nm-java.appspot.com/Check_License/Dir_My_App/Dir_ABC/My_Obj_123 is asking for the object "My_Obj_123" [ ignore the dirs ] and return the object from the datastore. Now I'm getting this : Error: Not Found The requested URL /Check_License/Dir_My_App/Dir_ABC/My_Obj_123 was not found on this server. Where in my servlet and how do I detect the request for this non exist Url ?

    Read the article

  • Specifying character

    - by danutenshu
    So below I have a code in C++ that is supposed to invert the arguments in a vector, but not the sequence. I have listed my problems as sidenotes in the code below. The invert function is supposed to invert each argument, and then the main function just outputs the inverted words in same order For instance, program("one two three four")=ruof eerth owt eno #include <iostream> #include <string> using namespace std; int invert(string normal) { string inverted; for (int num=normal.size()-1; num>=0; num--) { inverted.append(normal[num]); //I don't know how to get each character //I need another command for append } return **inverted**; <---- } int main(int argc, char* argv[]) { string text; for (int a=1; a<argc; a++) { text.append(invert(argv[a])); //Can't run the invert function text.append(" "); } cout << text << endl; return 0; }

    Read the article

  • LINQ to SQL Where Clause Optional Criteria

    - by RSolberg
    I am working with a LINQ to SQL query and have run into an issue where I have 4 optional fields to filter the data result on. By optional, I mean has the choice to enter a value or not. Specifically, a few text boxes that could have a value or have an empty string and a few drop down lists that could have had a value selected or maybe not... For example: using (TagsModelDataContext db = new TagsModelDataContext()) { var query = from tags in db.TagsHeaders where tags.CST.Equals(this.SelectedCust.CustCode.ToUpper()) && Utility.GetDate(DateTime.Parse(this.txtOrderDateFrom.Text)) <= tags.ORDDTE && Utility.GetDate(DateTime.Parse(this.txtOrderDateTo.Text)) >= tags.ORDDTE select tags; this.Results = query.ToADOTable(rec => new object[] { query }); } Now I need to add the following fields/filters, but only if they are supplied by the user. Product Number - Comes from another table that can be joined to TagsHeaders. PO Number - a field within the TagsHeaders table. Order Number - Similar to PO #, just different column. Product Status - If the user selected this from a drop down, need to apply selected value here. The query I already have is working great, but to complete the function, need to be able to add these 4 other items in the where clause, just don't know how!

    Read the article

  • Is memory allocation in linux non-blocking?

    - by Mark
    I am curious to know if the allocating memory using a default new operator is a non-blocking operation. e.g. struct Node { int a,b; }; ... Node foo = new Node(); If multiple threads tried to create a new Node and if one of them was suspended by the OS in the middle of allocation, would it block other threads from making progress? The reason why I ask is because I had a concurrent data structure that created new nodes. I then modified the algorithm to recycle the nodes. The throughput performance of the two algorithms was virtually identical on a 24 core machine. However, I then created an interference program that ran on all the system cores in order to create as much OS pre-emption as possible. The throughput performance of the algorithm that created new nodes decreased by a factor of 5 relative the the algorithm that recycled nodes. I'm curious to know why this would occur. Thanks. *Edit : pointing me to the code for the c++ memory allocator for linux would be helpful as well. I tried looking before posting this question, but had trouble finding it.

    Read the article

  • Ideas for storing e-mail messages in a Delphi client server application

    - by user193655
    There are many suggestions here and there for storing e-mail messages. Somehow what I am doing is writing an Outlook addin to send emails from inbox/sent folders directly to my application. So only what is really interesting is saved. And I decide where to save it. Imagine this case: I recieve an email from a customer. It's up to me to decide whether I should save it on the customer or on the order 24 that that customer did. So this is why I am doing the add in, and not some automatic storing of emails = noise after some time. This said, how to store the emails? For the emails that I recieve or send through Outlook the idea could be save the whole file in a blob field (so the eml file), may be I can save also other info (like the subject) in another text field. But the problem comes when I write an email from my application. In this case I am not generating an eml file, I send through MAPI data to Outlook to compose an email that I will send with Outlook (so in this case I cannot save the eml), or I directly send it with Indy. Also in this case I don't have the eml file... One idea could be that the all the emails that I auto compose have a special flag that the Add in recognises and therefore when I send the mail it is stored back to the DB. So in this case I can save the eml also of the mails I sent from my application. May you comment?

    Read the article

  • Appending Comment Number Anchors to Comments

    - by John
    Hello, I am using a PHP file called comments.php that has a query that enters values into a mySQL table called "comment." As the query does this, it auto-generates a field called "commentid", which is set to auto_increment in MySQL. The file also contains a loop what echoes out all comments for a given submission. It all works fine and dandy, but I want to simultaneously pull this "commentid" and turn it into a hashtag / anchor that when appended to the end of the URL makes that comment at the top of the user's browser. Someone said on another question that in order to do this one thing I should do is create an anchor on the row where the comment is being printed out. How can I do this? Thanks in advance, John The query that inserts comments into the MySQL table "comment": $query = sprintf("INSERT INTO comment VALUES (NULL, %d, %d, '%s', NULL)", $uid, $subid, $comment); mysql_query($query) or die(mysql_error()); The fields in the table "comment": commentid loginid submissionid comment datecommented The row in a loop where the comments are echoed out: echo '<td rowspan="3" class="commentname1">'.stripslashes($row["comment"]).'</td>';

    Read the article

  • Python : How to close a UDP socket while is waiting for data in recv ?

    - by alexroat
    Hello, let's consider this code in python: import socket import threading import sys import select class UDPServer: def __init__(self): self.s=None self.t=None def start(self,port=8888): if not self.s: self.s=socket.socket(socket.AF_INET, socket.SOCK_DGRAM) self.s.bind(("",port)) self.t=threading.Thread(target=self.run) self.t.start() def stop(self): if self.s: self.s.close() self.t.join() self.t=None def run(self): while True: try: #receive data data,addr=self.s.recvfrom(1024) self.onPacket(addr,data) except: break self.s=None def onPacket(self,addr,data): print addr,data us=UDPServer() while True: sys.stdout.write("UDP server> ") cmd=sys.stdin.readline() if cmd=="start\n": print "starting server..." us.start(8888) print "done" elif cmd=="stop\n": print "stopping server..." us.stop() print "done" elif cmd=="quit\n": print "Quitting ..." us.stop() break; print "bye bye" It runs an interactive shell with which I can start and stop an UDP server. The server is implemented through a class which launches a thread in which there's a infinite loop of recv/*onPacket* callback inside a try/except block which should detect the error and the exits from the loop. What I expect is that when I type "stop" on the shell the socket is closed and an exception is raised by the recvfrom function because of the invalidation of the file descriptor. Instead, it seems that recvfrom still to block the thread waiting for data even after the close call. Why this strange behavior ? I've always used this patter to implements an UDP server in C++ and JAVA and it always worked. I've tried also with a "select" passing a list with the socket to the xread argument, in order to get an event of file descriptor disruption from select instead that from recvfrom, but select seems to be "insensible" to the close too. I need to have a unique code which maintain the same behavior on Linux and Windows with python 2.5 - 2.6. Thanks.

    Read the article

  • How to use db4o IObjectContainer in a web application ? (Container lifetime ?)

    - by driis
    I am evaluating db4o for persistence for a ASP .NET MVC project. I am wondering how I should use the IObjectContainer in a web context with regards to object lifetime. As I see it, I can do one of the following: Create the IObjectContainer at application startup and keep the same instance for the entire application lifetime. Create one IObjectContainer per request. Start a server, and get a client IObjectContainer for each database interaction. What are the implications of these options, in terms of performance and concurrency ? Since the database is locked when an IObjectContainer is opened, I am pretty sure that option 2) would get me some problems with concurrency - would this also be the case for option 1 ? As I understand it, if I retrieve an object from an IObjectContainer, it must be saved by the same IObjectContainer instance - in order for db4o to identify it as being the same object. Therefore, If I choose option 3), I would have to retrieve the original object, make the necessary changes (copy data from a modified object), and then store it using the same IObjectContainer. Is this true ?

    Read the article

  • How to determine a text block of a file in one version come from which file in the previous version?

    - by Muhammad Asaduzzaman
    The problem is described below: Suppose I have a list of files in one version(say A,B,C,D). In the next version I have the following files(A,E,F,G). There are some similarities in their contents. The files in the later version comes from the previous version by file name renaming, content addition, deletion or partial modification or without any change( for example A is not changed). I take a block of text from a file(E, 2nd version) and check which files(in the 1st version) contain this text block. I found that B,C and D contain the text fragment. I want to determine from which file(B or c or d) this text block actually comes from.(I assume that E is a file whose name change in the second version). Since the contents may be changed, added or deleted in the later version, so in order to determine similarity I use LCS algorithm. But I cannot map the file with its previous version. I think one possible approach might be to use the location information of the match text blocks. But this heuristics not always work. Is there any research or algorithm exist to find so. Any direction will be helpful. Thanks in advance.

    Read the article

  • Can I place AdSense ads on a site with drug content?

    - by Joe Majewski
    I am going to be opening a new WordPress blog today, and I was curious to know if my site will be appropriate for AdSense ads. First off, the blog is going to be about drug addiction. More specifically, opiate addiction. I myself was addicted to pain killers for three years, and I am pleased to say that I am now in treatment and I have not used in over a month now. :) Anyways, my site will be an informative blog about opiates and the harm that they can induce on one's life. It will in no way endorse the use of drugs, but I may talk about my negative experiences. It will be 100% (without a doubt) evident upon checking out my website that my view on drugs is negative. Two questions: (1) Is this content acceptable for Google's terms of service? (2) In order to begin displaying AdSense ads, is there anything I must first do? I already have AdSense ads running on one of my domains. Can I simply begin pasting the code snippets into my new domain and watch as the ads begin to work? Thanks for your time. :)

    Read the article

  • The question about the basics of LINQ to SQL working

    - by Alex
    I just started learning LINQ to SQL, and so far I'm impressed with the easy of use and good performance. I used to think that when doing LINQ queries like from Customer in DB.Customers where Customer.Age > 30 select Customer Get all customers from the database ("SELECT * FROM Customers"), move them to the Customers array and then make a search in that Array using .NET methods. This is very inefficient, what if there are hundreds of thousands of customers in the database? Making such big SELECT queries would kill the web application. Now after experiencing how actually fast LINQ to SQL is, I start to suspect that when doing that query I just wrote, LINQ somehow converts it to a SQL Query string SELECT * FROM Customers WHERE Age > 30 And only when necessary it will run the query. So my question is: am I right? And when is the query actually run? The reason why I'm asking is not only because I want to understand how it works in order to build good optimized applications, but because I came across the following problem. I have 2 tables, one of them is Books, the other has information on how many books were sold on certain days. My goal is to select books that had at least 50 sales/day in past 10 days. It's done with this simple query: from Book in DB.Books where (from Sale in DB.Sales where Sale.SalesAmount >= 50 and Sale.DateOfSale >= DateTime.Now.AddDays(-10) select Sale.BookID).Contains(Book.ID) select Book The point is, I have to use the checking part in several queries and I decided to create an array with IDs of all popular books: var popularBooksIDs = from Sale in DB.Sales where Sale.SalesAmount >= 50 and Sale.DateOfSale >= DateTime.Now.AddDays(-10) select Sale.BookID; BUT when I try to do the query now: from Book in DB.Books where popularBooksIDs.Contains(Book.ID) select Book It doesn't work! That's why I think that we can't use thins kinds of shortcuts in LINQ to SQL queries, like we can't use them in real SQL. We have to create straightforward queries, am I right?

    Read the article

  • Should I pass a SqlDataReader by reference or not when passing it out to multiple threads.

    - by deroby
    Hi all, being new to c# I've run into this 'conundrum' when passing around a SqlDataReader between different threads. Without going into too much detail, the idea is to have a main thread fetching data from the database (a large recordset) and then have a helper-task run through this record by record and doing some stuff based upon the contents of this. There is no feedback to the recordset, it simply wades through until no records are left. This works fine, but given the nature of the job at hand it should be possible to have this job spread over different threads (CPUs) to maximize throughput (the order of execution is of no significance). The question then becomes, when I pass this recordset in a SqlDataReader, do I have to use ref or not ? It kind of boils down to the question : if I pass the object around without specifying ref, won't it create new copies in memory and have records processed n times ? Or, don't I risk having the record-position being moved forward while not all fields have been fully read yet ? The latter seems more like a 'data racing' issue and probably is covered by the lock()ing mechanism (or not?). My initial take on the problem was that it doesn't really hurt passing the variable using ref, yet as a colleague put it : "you only need ref when you're doing something wrong" =) Additionally using ref restricts me from applying a Using() construction too which isn't very nice either. I thus create a "basic" project that tackles the same approach but without the ref notation. Tests so far show that it works flawlessly on a Core2Duo (2cpu) using any number of threads, yet I'm still a bit wary... What do you experts think about this ? Use ref or not ? You can find the test-project here as it seems I can't upload it to this question directly ?!? ps: it's just a test-project and I'm new to c#, so please be gentle on me when breaking down the code =P

    Read the article

  • Help with MySQL query... Need help ordering a group of rows

    - by user156814
    I can tell it best by explaining the query I have, and what I need. I need to be able to get a group of items from the database, grouped by category, manufacturer, and year made. The groupings need to be sorted based on total amount of items within the group. This part is done with the query below. Secondly, I need to be able to show an image of the most expensive item out of the group, which is why I use MAX(items.current_price). I thought MAX() gets the ENTIRE row corresponding to the largest column value. I was wrong, as MAX only gets the numeric value of the largest price. So the query doesnt work well for that. SELECT items.id, items.year, items.manufacturer, COUNT(items.id) AS total, MAX(items.current_price) AS price, items.gallery_url, FROM ebay AS items WHERE items.primary_category_id = 213 AND items.year <> '' AND items.manufacturer <> '' AND items.bad_item <> 1 GROUP BY items.primary_category_id, items.manufacturer, items.year ORDER BY total DESC, price ASC LIMIT 10 if that doesnt explain it well, the results should be something like this id 10548 year 1989 manufacturer bowman total 451 price 8500.00 (The price of the most expensive item in the table/ not the price of item 10548) gallery_url http://ebay.xxxxx (The image of item 10548) A little help please. Thanks

    Read the article

  • C#: Need one of my classes to trigger an event in another class to update a text box

    - by Matt
    Total n00b to C# and events although I have been programming for a while. I have a class containing a text box. This class creates an instance of a communication manager class that is receiving frames from the Serial Port. I have this all working fine. Every time a frame is received and its data extracted, I want a method to run in my class with the text box in order to append this frame data to the text box. So, without posting all of my code I have my form class... public partial class Form1 : Form { CommManager comm; public Form1() { InitializeComponent(); comm = new CommManager(); } private void updateTextBox() { //get new values and update textbox } . . . and I have my CommManager class class CommManager { //here we manage the comms, recieve the data and parse the frame } SO... essentially, when I parse that frame, I need the updateTextBox method from the form class to run. I'm guessing this is possible with events but I can't seem to get it to work. I tried adding an event handler in the form class after creating the instance of CommManager as below... comm = new CommManager(); comm.framePopulated += new EventHandler(updateTextBox); ...but I must be doing this wrong as the compiler doesn't like it... Any ideas?!

    Read the article

  • Optimize master-detail insert statements

    - by Dave Jarvis
    Quest After a day of running (against nearly 1 GB of data), a set of statements are tumbling down to 40 inserts per second. I am looking to increase that by an order of magnitude or two. SQL Code The code to insert the information comes in two parts: a master record and detail records. The master record: INSERT INTO MONTH_REF (DISTRICT_ID, STATION_ID, CATEGORY_ID, YEAR, MONTH) VALUES ('101', '0066', '010', 1984, 07); The detail records: INSERT INTO DAILY (MONTH_REF_ID, AMOUNT, DAILY_FLAG_ID, DAY) VALUES ((SELECT ID FROM MONTH_REF M WHERE M.DISTRICT_ID = '101' AND M.STATION_ID = '0066' AND M.CAT EGORY_ID = '010' AND M.YEAR = 1984 AND M.MONTH = 07), 0, ' ', 1); INSERT INTO DAILY (MONTH_REF_ID, AMOUNT, DAILY_FLAG_ID, DAY) VALUES ((SELECT ID FROM MONTH_REF M WHERE M.DISTRICT_ID = '101' AND M.STATION_ID = '0066' AND M.CAT EGORY_ID = '010' AND M.YEAR = 1984 AND M.MONTH = 07), 0.5, ' ', 2); INSERT INTO DAILY (MONTH_REF_ID, AMOUNT, DAILY_FLAG_ID, DAY) VALUES ((SELECT ID FROM MONTH_REF M WHERE M.DISTRICT_ID = '101' AND M.STATION_ID = '0066' AND M.CAT EGORY_ID = '010' AND M.YEAR = 1984 AND M.MONTH = 07), 0, 'T', 3); Proposed Solution INSERT INTO MONTH_REF (DISTRICT_ID, STATION_ID, CATEGORY_ID, YEAR, MONTH) VALUES ('101', '0066', '010', 1984, 07); SET @month_ref_id := (SELECT LAST_INSERT_ID()); INSERT INTO DAILY (MONTH_REF_ID, AMOUNT, DAILY_FLAG_ID, DAY) VALUES (@month_ref_id, 0, ' ', 1); INSERT INTO DAILY (MONTH_REF_ID, AMOUNT, DAILY_FLAG_ID, DAY) VALUES (@month_ref_id, 0.5, ' ', 2); INSERT INTO DAILY (MONTH_REF_ID, AMOUNT, DAILY_FLAG_ID, DAY) VALUES (@month_ref_id, 0, 'T', 3); Constraints The MONTH_REF table has an AUTO_INCREMENT primary key and is indexed on it. The DAILY table has no index and no primary key. A primary key can be added to the DAILY table, if it would help. Question Is there a more efficient way to execute the (billion or so) insert statements than the proposed solution? Thank you!

    Read the article

  • Why do .NET developers offer 32-bit/64-bit versions of .NET assemblies?

    - by Tyler
    Evey now and then I see both x86 and x64 versions of a .NET assembly. Consider the following web part for SharePoint. Why wouldn't the developer just offer a single version and have let the JIT compiler sort out the rest? When I see these kinds offering is it just that the developer decided to create a native image using a tool like ngen in order to avoid a JIT? Someone please help me out here, I feel like I'm missing something of note. Updated From what I got below, both x86 and x64 builds are offered because one or more of the following reasons: The developer wanted to avoid JITing and created a native image of his code, targeting a given architecture using a tool like ngen.exe. The assembly contains platform specific COM calls and so it makes no point to build it as AnyCPU. In these cases builds that target different platforms may contain different code. The assembly may contain Win32 calls using pinvoke which won't get remapped by a JIT and so the build should target the platform it is bound to.

    Read the article

< Previous Page | 592 593 594 595 596 597 598 599 600 601 602 603  | Next Page >