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  • Don't Understand Sql Server Error

    - by Jonathan Wood
    I have a table of users (User), and need to create a new table to track which users have referred other users. So, basically, I'm creating a many-to-many relation between rows in the same table. So I'm trying to create table UserReferrals with the columns UserId and UserReferredId. I made both columns a compound primary key. And both columns are foreign keys that link to User.UserID. Since deleting a user should also delete the relationship, I set both foreign keys to cascade deletes. When the user is deleted, any related rows in UserReferrals should also delete. But this gives me the message: 'User' table saved successfully 'UserReferrals' table Unable to create relationship 'FK_UserReferrals_User'. Introducing FOREIGN KEY constraint 'FK_UserReferrals_User' on table 'UserReferrals' may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints. Could not create constraint. See previous errors. I don't get this error. A cascading delete only deletes the row with the foreign key, right? So how can it cause "cycling cascade paths"? Thanks for any tips.

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  • WordPress - Each page of paged posts all show same posts

    - by j-man86
    I set up a pagination function for my wordpress blog. When clicking to the next page, the URL is correct: "/page/1", "/page/2", "/page/3" etc, but the actual posts don't change from page to page (page 2 and page 3 still display the first page of posts). Here's the code I'm using for the loop: <?php $paged = (get_query_var('paged')) ? get_query_var('paged') : 1; $sticky=get_option('sticky_posts'); $args=array( 'offset' => 1, 'category__not_in' => array(-6), 'paged'=>$paged, 'showposts' => 6, ); query_posts($args); if ( $wp_query->have_posts() ) : while ( $wp_query->have_posts() ) : $wp_query->the_post(); ?> Any help/insight would be much appreciated. Thank you!

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  • Which key:value store to use with Python?

    - by Kurt
    So I'm looking at various key:value (where value is either strictly a single value or possibly an object) stores for use with Python, and have found a few promising ones. I have no specific requirement as of yet because I am in the evaluation phase. I'm looking for what's good, what's bad, what are the corner cases these things handle well or don't, etc. I'm sure some of you have already tried them out so I'd love to hear your findings/problems/etc. on the various key:value stores with Python. I'm looking primarily at: memcached - http://www.danga.com/memcached/ python clients: http://pypi.python.org/pypi/python-memcached/1.40 http://www.tummy.com/Community/software/python-memcached/ CouchDB - http://couchdb.apache.org/ python clients: http://code.google.com/p/couchdb-python/ Tokyo Tyrant - http://1978th.net/tokyotyrant/ python clients: http://code.google.com/p/pytyrant/ Lightcloud - http://opensource.plurk.com/LightCloud/ Based on Tokyo Tyrant, written in Python Redis - http://code.google.com/p/redis/ python clients: http://pypi.python.org/pypi/txredis/0.1.1 MemcacheDB - http://memcachedb.org/ So I started benchmarking (simply inserting keys and reading them) using a simple count to generate numeric keys and a value of "A short string of text": memcached: CentOS 5.3/python-2.4.3-24.el5_3.6, libevent 1.4.12-stable, memcached 1.4.2 with default settings, 1 gig memory, 14,000 inserts per second, 16,000 seconds to read. No real optimization, nice. memcachedb claims on the order of 17,000 to 23,000 inserts per second, 44,000 to 64,000 reads per second. I'm also wondering how the others stack up speed wise.

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  • jquery ui dialog fixed positioning

    - by sofia
    Hi, I needed the dialog to maintain its position fixed even if the page scrolled, so i used the extension at http://forum.jquery.com/topic/dialog-position-fixed-12-1-2010 but there's 2 problems with it: it flickers in IE and Firefox on page scroll (in Safari/Chrome it's fine) on closing and then reopening, it looses its stickyness and scrolls along with the page. Here's the code i'm using for creating the dialog: $('<div id="'+divpm_id+'"><div id="inner_'+divpm_id+'"></div><textarea class="msgTxt" id="txt'+divpm_id+'" rows="2"></textarea></div>') .dialog({ autoOpen: true, title: user_str, height: 200, stack: true, sticky: true //uses ui dialog extension to keep it fixed }); And here's the code i'm using for reopening it: jQuery('#'+divpm_id).parent().css('display','block'); Suggestions/solutions? Thanks

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  • How to make QT support HTML 5 database?

    - by Mickey Shine
    I am using Qt 4.7.1 and embedded a webview in my app. But I got the following error when trying to visit http://webkit.org/demos/sticky-notes/ to test the HTML 5 database feature Failed to open the database on disk. This is probably because the version was bad or there is not enough space left in this domain's quota I compiled my static Qt library with the following command: configure --prefix=/usr/local/qt-static-release-db --accessibility --multimedia --audio-backend --svg --webkit --javascript-jit --script --scripttools --declarative --release -nomake examples -nomake demos --static --openssl -I /usr/local/ssl/include -L /usr/local/ssl/lib -confirm-license -sql-qsqlite -sql-qmysql -sql-qodbc

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  • jQuery: How to disable tooltip

    - by epitka
    Is there a way to disable browser tooltip from displaying when hovering over elements that have attribute 'title' populated? Note that I don't want to remove title content. Here is the code are requested: $(document).ready(function() { $('a.clickableSticky').cluetip({ splitTitle: '|', showTitle: false, titleAttribute: 'description', activation: 'click', sticky: true, arrows: true, closePosition: 'title' }); }); and in asp.net <ItemTemplate> <a class="clickableSticky" href="#" title=' <%#((Limit)Container.DataItem).Tip %>'> <img src="..\App_Themes\default\images\icons\information.png"/> </a> </ItemTemplate>

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  • How do I manage application configuration in ASP.NET?

    - by GlennS
    I am having difficulty with managing configuration of an ASP.Net application to deploy for different clients. The sheer volume of different settings which need twiddling takes up large amounts of time, and the current configuration methods are too complicated to enable us to push this responsibility out to support partners. Any suggestions for better methods to handle this or good sources of information to research? How we do things at present: Various xml configuration files which are referenced in Web.Config, for example an AppSettings.xml. Configurations for specific sites are kept in duplicate configuration files. Text files containing lists of data specific to the site In some cases, manual one-off changes to the database C# configuration for Windsor IOC. The specific issues we are having: Different sites with different features enabled, different external services we have to talk to and different business rules. Different deployment types (live, test, training) Configuration keys change across versions (get added, remove), meaning we have to update all the duplicate files We still need to be able to alter keys while the application is running Our current thoughts on how we might approach this are: Move the configuration into dynamically compiled code (possibly Boo, Binsor or JavaScript) Have some form of diffing/merging configuration: combine a default config with a live/test/training config and a site-specific config

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  • Android: How to get a custom view to redraw partially?

    - by Peterdk
    I have a custom view that fills my entire screen. (A piano keyboard) When a user touches the key, it would cause a invalidate() to be called and the whole keyboard gets redrawn to show the new state with a touched key. Currently the view is very simple, but I plan to add a bit more nice graphics. Since the whole keyboard is dynamically rendered this would make redrawing the entire keyboard more expensive. So I thought, let's look into partial redrawing. Now I call invalidate(Rect dirty) with the correct dirty region. I set my onDraw(Canvas canvas) method to only draw the keys in the dirty region if I do indeed want a partial redraw. This results in those keys being drawn, but the rest of the keyboard is totally black/not drawn at all. Am I wrong in expecting that calling invalidate(Rect dirty) would "cache" the current canvas, and only "allows" drawing in the dirty region? Is there any way I can achieve what I want? (A way to "cache" the canvas and only redraw the dirty area?"

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  • Alternative to array_shift function

    - by SoLoGHoST
    Ok, I need keys to be preserved within this array and I just want to shift the 1st element from this array. Actually I know that the first key of this array will always be 1 when I do this: // Sort it by 1st group and 1st layout. ksort($disabled_sections); foreach($disabled_sections as &$grouplayout) ksort($grouplayout); Basically I'd rather not have to ksort it in order to grab this array where the key = 1. And, honestly, I'm not a big fan of array_shift, it just takes to long IMO. Is there another way. Perhaps a way to extract the entire array where $disabled_sections[1] is found without having to do a foreach and sorting it, and array_shift. I just wanna add $disabled[1] to a different array and remove it from this array altogether. While keeping both arrays keys structured the way they are. Technically, it would even be fine to do this: $array = array(); $array = $disabled_sections[1]; But it needs to remove it from $disabled_sections. Can I use something like this approach... $array = array(); $array = $disabled_sections[1]; $disabled_sections -= $disabled_sections[1]; Is something like the above even possible?? Thanks.

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  • Single Sign On for WebServices, WCS, WFS, WMS (Geoserver), etc.

    - by lajuette
    I'm trying to implement a Single Sign On (SSO) for a web application. Maybe you can help me find a proper solution, give me a direction or tell me, that solutions already exist. The scenario: A GeoExt (ExtJS for geodata/map based apps) webapp (JavaScript only) has a login form to let the user authenticate himself. The authentication is not implemented yet, so i'm flexible with respect to that. After authenticating to the main webapp the user indirectly accesses multiple 3rd-party services like WebServices, GeoServer WFS, Google Maps, etc. These services might require additional authentication like credentials or keys. We are (so far) not talking about additional login screens, just some kind of "machine to machine"-authentication. The main problem: I'm unable to modify the 3rd party services (e.g. Google) to add a SSO mechanism. I'd like to have a solution that allows the user to log in once to have access to all the services required. My first idea was a repository that stores all the required credentials or keys. The user logs in and can retrieve all required information to acces sthe other services. Does anybody know of existing implementations, papers, maybe implementations of such services? Other requirements: The communication between the JS application and the repository must be secure. The credentials must be stored in a secure manner. But the JS app must be able to use them to access the services (no chance to store a decryption key in a JS-app securely, eh? *g).

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  • Kohana 3 ORM: How to get data from pivot table? and all other tables for that matter

    - by zenna
    I am trying to use ORM to access data stored, in three mysql tables 'users', 'items', and a pivot table for the many-many relationship: 'user_item' I followed the guidance from http://stackoverflow.com/questions/1946357/kohana-3-orm-read-additional-columns-in-pivot-tables and tried $user = ORM::factory('user',1); $user->items->find_all(); $user_item = ORM::factory('user_item', array('user_id' => $user, 'item_id' => $user->items)); if ($user_item->loaded()) { foreach ($user_item as $pivot) { print_r($pivot); } } But I get the SQL error: "Unknown column 'user_item.id' in 'order clause' [ SELECT user_item.* FROM user_item WHERE user_id = '1' AND item_id = '' ORDER BY user_item.id ASC LIMIT 1 ]" Which is clearly erroneous because Kohana is trying to order the elements by a column which doesn't exist: user_item.id. This id doesnt exist because the primary keys of this pivot table are the foreign keys of the two other tables, 'users' and 'items'. Trying to use: $user_item = ORM::factory('user_item', array('user_id' => $user, 'item_id' => $user->items)) ->order_by('item_id', 'ASC'); Makes no difference, as it seems the order_by() or any sql queries are ignored if the second argument of the factory is given. Another obvious error with that query is that the item_id = '', when it should contain all the elements. So my question is how can I get access to the data stored in the pivot table, and actually how can I get access to the all items held by a particular user as I even had problems with that? Thanks

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  • Mode specific key bindings

    - by rejeep
    Hey, I have a minor mode that also comes with a global mode. The mode have some key bindings and I want the user to have the posibility to specify what bindings should work for each mode. (my-minor-mode-bindings-for-mode 'some-mode '(key1 key2 ...)) (my-minor-mode-bindings-for-mode 'some-other-mode '(key3 key4 ...)) So I need some kind of mode/buffer-local key map. Buffer local is a bit problematic since the user can change the major mode. I have tried some solutions of which neither works any good. Bind all possible keys always and when the user types the key, check if the key should be active in that mode. Execute action if true, otherwise fall back. Like the previous case only that no keys are bound. Instead I use a pre command hook and check if the key pressed should do anything. For each buffer update (whatever that means), run a function that first clears the key map and then updates it with the bindings for that particular mode. I have tried these approaches and I found problems with all of them. Do you know of any good way to solve this? Thanks!

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  • Is it practical to program with your feet?

    - by bmm
    Has anyone tried using foot pedals in addition to the traditional keyboard and mouse combo to improve your effectiveness in the editor? Any actual experiences out there? Does it work, or is it just for carpal tunnel relief? I found one blog entry from a programmer who actually tried it: So now I can type using my feet for most of the modifier keys. I am using the pedals as I type this. I am still getting used to them, but the burning in my left wrist has definitely reduced. I think I can also type a little faster, but I am too lazy to do the speed tests with and without the pedals to verify this. On the negative side: Working out where to put your feet when you aren’t typing can be a little awkward. The pedals tend to move around the carpet, despite being metal and quite heavy. Some small spikes might have helped. Although the travel on the pedals is small, they are surprisingly stiff. Another programmer's experience: Anybody with hand pain must get foot pedals, since they can remove a tremendous load from your hands. I have two foot pedals, and use one for the SHIFT key, and the other for the CONTROL key. (I still type META by hand.) I have found that in the process of using the Emacs text editor to compose computer programs, I tend to use the SHIFT, CONTROL and META keys constantly, and it is easy to remove most of this load from one's hands. Some foot switch products: Savant Elite Triple Foot Switch FragPedal Bilbo Step On It!

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  • Why can't I set boolean columns with update?

    - by Benjamin Oakes
    I'm making a user administration page. For the system I'm creating, users need to be approved. Sometimes, there will be many users to approve, so I'd like to make that easy. I'm storing this as a boolean column called approved. I remembered the Edit Multiple Individually Railscast and thought it would be a great fit. However, I'm running into problems which I traced back to ActiveRecord::Base#update. update works fine in this example: >> User.all.map(&:username) => ["ben", "fred"] >> h = {"1"=>{'username'=>'benjamin'}, "2"=>{"username"=>'frederick'}} => {"1"=>{"username"=>"benjamin"}, "2"=>{"username"=>"frederick"}} >> User.update(h.keys, h.values) => ... >> User.all.map(&:username) => ["benjamin", "frederick"] But not this one: >> User.all.map(&:approved) => [true, nil] >> h = {"1"=>{'approved'=>'1'}, "2"=>{'approved'=>'1'}} >> User.update(h.keys, h.values) => ... >> User.all.map(&:approved) => [true, nil] Chaging from '1' to true didn't make a difference when I tested. What am I doing wrong?

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  • How can I use Spring Security without sessions?

    - by Jarrod
    I am building a web application with Spring Security that will live on Amazon EC2 and use Amazon's Elastic Load Balancers. Unfortunately, ELB does not support sticky sessions, so I need to ensure my application works properly without sessions. So far, I have setup RememberMeServices to assign a token via a cookie, and this works fine, but I want the cookie to expire with the browser session (e.g. when the browser closes). I have to imagine I'm not the first one to want to use Spring Security without sessions... any suggestions?

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  • Eclipse says I don't implement Enumeration, but I do

    - by Harm De Weirdt
    Goodmorning everybody, I'm having a little problem with a project for school. We are told to make an Iterator that implements Enumeration over a Hashmap. So i made this Enumeration: public Enumeration<Object> getEnumeration() { return new Enumeration<Object>() { private int itemsDone = 0; Collection<Long> keysCollection = getContent().keySet(); Long [] keys = keysCollection.toArray(new Long[keysCollection.size()]); @Override public boolean hasMoreElements() { if(itemsDone < getContent().size() +1 ) { return true; }else { return false; } } @Override public Object nextElement() { return getContent().get(keys[itemsDone++]); } }; } This goes in my Backpack class public class Backpack extends Item implements Carrier, Enumeration<Object>{ The hashmap is returned by getContent(). The problem now is that eclipse keeps telling me I havent implemented the methods from Enumeration. If I use the quick fix it just adds the hasMoreElements() and nextElement() dummy methods in my class. Somehow it doesn't see these methods in the inner class.. Can anyone help me please? Any help is appreciated.

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  • Need help choosing database server

    - by The Pretender
    Good day everyone. Recently I was given a task to develop an application to automate some aspects of stocks trading. While working on initial architecture, the database dilemma emerged. What I need is a fast database engine which can process huge amounts of data coming in very fast. I'm fairly experienced in general programming, but I never faced a task of developing a high-load database architecture. I developed a simple MSSQL database schema with several many-to-many relationships during one of my projects, but that's it. What I'm looking for is some advice on choosing the most suitable database engine and some pointers to various manuals or books which describe high-load database development. Specifics of the project are as follows: OS: Windows NT family (Server 2008 / 7) Primary platform: .NET with C# Database structure: one table to hold primary items and two or three tables with foreign keys to the first table to hold additional information. Database SELECT requirements: Need super-fast selection by foreign keys and by combination of foreign key and one of the columns (presumably DATETIME) Database INSERT requirements: The faster the better :) If there'll be significant performance gain, some parts can be written in C++ with managed interfaces to the rest of the system. So once again: given all that stuff I just typed, please give me some advice on what the best database for my project is. Links or references to some manuals and books on the subject are also greatly appreciated. EDIT: I'll need to insert 3-5 rows in 2 tables approximately once in 30-50 milliseconds and I'll need to do SELECT with 0-2 WHERE clauses queries with similar rate.

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  • Hot to make COM ActiveX object work in IE 64 bit?

    - by Kurtevich
    Hi! I have a COM object embeded in ASP.NET page using <object classid="clsid:XXX...">. It works in IE 32 bit, but does not work in IE 64 bit - can't access its functions. There are no error messages, no event logs where I can get some information. The dll is in C#, includes COM visible class, compiled for Any CPU (though I also tried x86), and registered during client installation by executing regasm. This creates registry keys, well everything works fine except for IE 64. I searched internet about the issue or at least some guidlines and didn't find anything. I received an answer on another forum, something about _MERGE_PROXYSTUB (I guess it's preprocessor definition?) and ProxyStubClsid32 registry key, but not very detailed. Well, I searched again, didn't find much, and experimented: rebuilt with _MERGE_PROXYSTUB defined, created ProxyStubClsid32 keys everywhere, but with no result. What can be at least possible solutions or points to look at? Maybe there is a way at least to get the logs about why IE 64 can't access it?

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  • Wrong EXE file shown in start menu on Windows 7

    - by Zach
    Hello all, My software has two .EXE files : A.exe and B.exe. After installed on Window 7, the shortcut to A.exe is always shown in the start menu. (I don't know if 'Start menu' is the correct name or not, what I mean is the area above 'All Programs'). The menu in my computer looks like: Getting Started Windows Media Center Calculator Sticky Notes Snipping Tool Paint A <-- My program, and I want 'B' to be shown here All programs How can I make B.exe shown instead of A.exe? Best regards, Zach

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  • Why is OpenSubKey() returning null on my Win 7 64 bit system?

    - by BrMcMullin
    Has anyone seen OpenSubKey() and other Microsoft.Win32 registry functions return null on 64 bit systems when 32 bit registry keys are under Wow6432node in the registry? I'm working on a unit testing framework that makes a call to OpenSubKey() from the .net library. My dev system is a Win 7 64 bit environment with VS 2008 SP1 and the Win 7 SDK installed. The application we're unit testing is a 32 bit application, so the registry is virtualized under HKLM\Software\Wow6432node. When we call: Registry.LocalMachine.OpenSubKey( @"Software\MyCompany\MyApp\" ); Null is returned, however explicitly stating to look here works: Registry.LocalMachine.OpenSubKey( @"Software\Wow6432node\MyCompany\MyApp\" ); From what I understand this function should be agnostic to 32 bit or 64 bit environments and should know to jump to the virtual node. Even stranger is the fact that the exact same call inside a compiled and installed version of our application is running just fine on the same system and is getting the registry keys necessary to run; which are also being placed in HKLM\Software\Wow6432node. Any suggestions? Thanks in advance!

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  • encrypt apache and mysql servers

    - by stormdrain
    I have a question about encrypting disks. I have 2 servers: 1 is apache for web/frontend and it talks to server 2 which is mysql. They are all for intranet only; no external access. I was looking into using PGP or GnuPG to encrypt the disks. I'm not clear, though, as to exactly how this would work. Where would the keys be stored? On the client? On apache? If there is a key on apache to access mysql, does there need to be a key for each user? If so, if key 1 is used to alter some data, would then that data be inaccessible to a user using key 2? And the apache key, would that only be accessible to users with local keys? Is encryption done on the fly? Does it degrade performance? What would be the best approach to encrypt the data on these servers, but have them accessible to users? Thanks!

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  • mysql complex key or + auto increment key (guid)

    - by darko
    Hi, I have not very big db. I am using auto increment primary keys and in my case there is no problem with that. GUID is not necessary. I have a table containing this fields: from_destination to_testination shipper quantity Where the fields 1,2,3 needs to be unique. Also I have second table that for the fields 1,2,3 stores bought quantities per day One to many. from_destination to_destination shipper date reserved_quantity case 1 Is it better to make fields 1,2,3 as primary complex key in the first table and the same fields in the second table to be foreign key First table from_destination | to_destination | primary shipper | quaitity Second table second_id - autoincrement primary from_destination | to_destination | foreign key shipper | date reserved_quantity Case 2 or just to add auto increment filed in the first table and make fields 1,2,3 unique. In the second table there will be one ingeger foreign key pointing to the first table, and one auto increment key for the table. First table first_id - autoincrement primary from_destination | to_destination | unique shipper | quaitity Second table second_id - autoincrement primary first_id - forein date reserved_quantity If so why we need complex keys, when we can have one field auto increment or GUID and all other fields that are candidates for complex key to be unique. Regards

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  • How to create Dictionary object in AppDelegate to access objectkey in another ViewController

    - by TechFusion
    Hello, I have created Window Based application and tab bar controller as root controller. My objective is to store Text Field data values in one tab bar VC and will be accessible and editable by other VC and also retrievable when application start. I am looking to use NSDictionary class in AppDelegate so that I can access stroed Data Values with keys. //TestAppDelegate.h @interface { ..... .... NSDictionary *Data; } @property (nonatomic, retain) NSDictionary *Data; //TestAppDelegate.m #import "TestAppDelegate.h" NSString *kNamekey =@"Namekey"; NSString *kUserIDkey =@"UserIDkey"; NSString *kPasswordkey =@"Passwordkey"; @implemetation TestAppDelegate @synthesize Data; -(void)applicationDidFinishLaunching:(UIApplication)application { NSString *NameDefault; NSString *UserIDdefault; NSString *Passworddefault; NSString *testvalue = [[NSUserDefaults standardUserDefaults] stringForKey: kNamekey]; if(testvalue == nil) { NSDictionary *appDefaults = [NSDictionary dictionaryWithObjectsAndKeys: NameDefault, kNamekey, UserIdefault kUserIDkey, Passwordefault kPasswordkey, nil]; self.Data = appDefaults; [[NSUserDefaults standardUserDefaults] registerDefaults:appDefaults]; [[NSUserDefaults standardUserDefaults] synchronize]; } else { } } Here ViewController is ViewController of Navigation Controller which is attached with one tab bar.. I have attached xib file with ViewController //ViewController.h @interface IBOutlet UITextField *Name; IBOutlet UITextField *UserId; IBOutlet UITextField *Password; } @property(retain,nonatomic) IBOutlet UITextField *Name @property(retain,nonatomic) IBOutlet UITextField *UserId; @property(retain,nonatomic) IBOutlet UITextField *Password; -(IBAction)Save:(id)sender; @end Here in ViewController.m I want to store Text Field input data with key which are defined in AppDelegate. I have linked Save Barbutton with action. Here I am not getting how to access NSDictionary class with object and keys in ViewController. //ViewController.m -(IBAction)Save:(id)sender{ TestAppDelegate *appDelegate = (TestAppDelegate*)[[UIApplication sharedApplication] delegate]; //Here how to access knamekey here to set object(Name.test) value with key } Please guide me about this. Thanks,

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  • IE form input data disappear after browser refresh

    - by RWW
    Hi, I'm trying to achieve sticky forms without PHP. My setup is AJAX like javascript. The back/forward work fine on both IE and FF, but refresh only works on FF, not IE. Doesn't matter what cache options I use, I've even set IE's temporary files option to never check for updates, and the input value is gone after page refresh(the refresh button or F5) I've read many posts where people have the opposite problem, and do not want form data to persist across page refresh, and never read from browser cache, but I do. Any help is appreciated, thanks!

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  • How to prevent Hibernate from nullifying relationship column during entity removal

    - by Grzegorz
    I have two entities, A and B. I need to easily retrieve entities A, joined with entities B on the condition of equal values of some column (some column from A equal to some column in B). Those columns are not primary or foreign keys, they contain same business data. I just need to have access from each instance of A to the collection of B's with the same value of this column. So I model it like this: class A { @OneToMany @JoinColumn(name="column_in_B", referencedColumnName="column_in_A") Collection<B> bs; This way, I can run queries like "select A join fetch a.bs b where b...." (Actually, the real relationship here is many-to-many. But when I use @ManyToMany, Hibernate forces me to use join table, which doesnt exist here. So I have to use @OneToMany as workaround). So far so good. The main problem is: whenever I delete an instance of A, hibernate calls "Update B set column_in_B = null", becuase it thinks the column_in_B is foreign key pointing at primary key in A (and because row in A is deleted, it tries to clean the foreign key in B). BUT the column_in_B IS NOT a foreign key, and can't be modified, because it causes data lost (and this column is NOT NULL anyway in my case, causing data integerity exception to be thrown). Plese help me with this. How to model such relationships with Hibernate? (I would call it "virtual relationships", or "secondary relationships" or so: as they are not based on foreign keys, they are just some shortcuts which allows for retrieving related objects and quering for them with HQL)

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