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  • Fetch the most viewed data in databases

    - by Erik Edgren
    I want to get the most viewed photo from the database but I don't know how I shall accomplish this. Here's my SQL at the moment: SELECT * FROM photos AS p, viewers AS v WHERE p.id = v.id_photo GROUP BY v.id_photo The databases: CREATE TABLE IF NOT EXISTS `photos` ( `id` int(10) NOT NULL AUTO_INCREMENT, `photo_filename` varchar(50) NOT NULL, `photo_camera` varchar(150) NOT NULL, `photo_taken` datetime NOT NULL, `photo_resolution` varchar(10) NOT NULL, `photo_exposure` varchar(10) NOT NULL, `photo_iso` varchar(3) NOT NULL, `photo_fnumber` varchar(10) NOT NULL, `photo_focallength` varchar(10) NOT NULL, `post_coordinates` text NOT NULL, `post_description` text NOT NULL, `post_uploaded` datetime NOT NULL, `post_edited` datetime NOT NULL, `checkbox_approxcoor` enum('0','1') NOT NULL DEFAULT '0', PRIMARY KEY (`id`), UNIQUE KEY `id` (`id`) ) CREATE TABLE IF NOT EXISTS `viewers` ( `id` int(10) NOT NULL AUTO_INCREMENT, `id_photo` int(10) DEFAULT '0', `ipaddress` text NOT NULL, `date_viewed` datetime NOT NULL, PRIMARY KEY (`id`), UNIQUE KEY `id` (`id`) ) The data in viewers looks like this: (1, 85, '3892a0ab97d6ff325f285b27b847070f', '2012-06-21 22:49:25'), (2, 84, '3892a0ab97d6ff325f285b27b847070f', '2012-06-21 22:49:25'), (3, 85, '3892a0ab97d6ff325f285b27b847070f', '2012-06-21 22:49:25'); One single row from the database for photos to understand how the rows looks like in this database: (85, 'P1170986.JPG', 'Panasonic DMC-LX3', '2012-06-19 18:00:40', '3968x2232', '10/8000', '80', '50/10', '51/10', '', '', '2012-06-19 18:45:17', '0000-00-00 00:00:00', '0') At the moment the SQL only prints the photo with ID 84. In this case it's wrong - it should print out the photo with ID 85. How can I fix this problem? Thanks in advance.

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  • Delete throws "deleted object would be re-saved by cascade"

    - by Greg
    I have following model: <class name="Person" table="Person" optimistic-lock="version"> <id name="Id" type="Int32" unsaved-value="0"> <generator class="native" /> </id> <!-- plus some properties here --> </class> <class name="Event" table="Event" optimistic-lock="version"> <id name="Id" type="Int32" unsaved-value="0"> <generator class="native" /> </id> <!-- plus some properties here --> </class> <class name="PersonEventRegistration" table="PersonEventRegistration" optimistic-lock="version"> <id name="Id" type="Int32" unsaved-value="0"> <generator class="native" /> </id> <property name="IsComplete" type="Boolean" not-null="true" /> <property name="RegistrationDate" type="DateTime" not-null="true" /> <many-to-one name="Person" class="Person" column="PersonId" foreign-key="FK_PersonEvent_PersonId" cascade="all-delete-orphan" /> <many-to-one name="Event" class="Event" column="EventId" foreign-key="FK_PersonEvent_EventId" cascade="all-delete-orphan" /> </class> There are no properties pointing to PersonEventRegistration either in Person nor in Event. When I try to delete an entry from PersonEventRegistration, I get the following error: "deleted object would be re-saved by cascade" The problem is, I don't store this object in any other collection - the delete code looks like this: public bool UnregisterFromEvent(Person person, Event entry) { var registrationEntry = this.session .CreateCriteria<PersonEventRegistration>() .Add(Restrictions.Eq("Person", person)) .Add(Restrictions.Eq("Event", entry)) .Add(Restrictions.Eq("IsComplete", false)) .UniqueResult<PersonEventRegistration>(); bool result = false; if (null != registrationEntry) { using (ITransaction tx = this.session.BeginTransaction()) { this.session.Delete(registrationEntry); tx.Commit(); result = true; } } return result; } What am I doing wrong here?

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  • How to initialize an Object?

    - by John
    I have a class like this, public class person { name Name {set; get;} string Address {set; get;} } public class name { string First {set; get;} string Last {set; get;} } Now when I create the object an try to set the first or last name I get an error. "Object reference not set to an instance of an object." person Person = new person(); Person.Name.First = "John"; Person.Name.Last ="Smith"; What am I doing wrong?

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  • Object's field cannot be accessed after $.ajax call in success function - it is undefined

    - by dragonfly
    I have a $.ajax call and and server returns JSON. This is my call: var result; // tmp variable just for playing with Chrome console $.ajax({ type: "GET", url: "ashxJSON.ashx", data: { name: "some sample data" }, contentType: "application/json; charset=utf-8", dataType: "json", success: function (msg) { result = msg; console.log(msg); $("#output").append("<p>" + msg.message + "</p>"); }, error: function (jqXHR, textStatus, errorThrown) { console.log(textStatus); console.log(errorThrown); } }); Server returns exactly this string: { "messsage": "Hello World to ..."} And now, when I: console.log(msg) I see: Object messsage: "Hello World to..." proto: Object But when I access msg.message or msg["message"] I see: undefined What is wrong with me / that msg object?

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  • Using inheritance and polymorphism to solve a common game problem

    - by Barry Brown
    I have two classes; let's call them Ogre and Wizard. (All fields are public to make the example easier to type in.) public class Ogre { int weight; int height; int axeLength; } public class Wizard { int age; int IQ; int height; } In each class I can create a method called, say, battle() that will determine who will win if an Ogre meets and Ogre or a Wizard meets a Wizard. Here's an example. If an Ogre meets an Ogre, the heavier one wins. But if the weight is the same, the one with the longer axe wins. public Ogre battle(Ogre o) { if (this.height > o.height) return this; else if (this.height < o.height) return o; else if (this.axeLength > o.axeLength) return this; else if (this.axeLength < o.axeLength) return o; else return this; // default case } We can make a similar method for Wizards. But what if a Wizard meets an Ogre? We could of course make a method for that, comparing, say, just the heights. public Wizard battle(Ogre o) { if (this.height > o.height) return this; else if (this.height < o.height) return o; else return this; } And we'd make a similar one for Ogres that meet Wizard. But things get out of hand if we have to add more character types to the program. This is where I get stuck. One obvious solution is to create a Character class with the common traits. Ogre and Wizard inherit from the Character and extend it to include the other traits that define each one. public class Character { int height; public Character battle(Character c) { if (this.height > c.height) return this; else if (this.height < c.height) return c; else return this; } } Is there a better way to organize the classes? I've looked at the strategy pattern and the mediator pattern, but I'm not sure how either of them (if any) could help here. My goal is to reach some kind of common battle method, so that if an Ogre meets an Ogre it uses the Ogre-vs-Ogre battle, but if an Ogre meets a Wizard, it uses a more generic one. Further, what if the characters that meet share no common traits? How can we decide who wins a battle?

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  • Object comparison in JavaScript

    - by spankmaster79
    What is the best way to compare Objects in JavaScript? Example: var user1 = {name : "nerd", org: "dev"}; var user2 = {name : "nerd", org: "dev"}; var eq = user1 == user2; alert(eq); // gives false I know that "Two objects are equal if they refer to the exact same Object", but is there a way to check it another way?? Using this way works for me.....but is it the only possibility? var eq = Object.toJSON(user1) == Object.toJSON(user2); alert(eq); // gives true

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  • Storing a reference to an object in C#

    - by Jack
    I was wondering how one could store a reference to an object in .net. That is, I would like something like the following code (note, of course, that the following code may be way off from how to actually do it): class Test { private /*reference to*/ Object a; public Test(ref int a) { this.a = a; this.a = ((int)this.a) + 1; } public Object getA() { return this.a; } } /* * ... */ static void Main(string[] args) { int a; a=3; Test t = new Test(ref a); Console.WriteLine(a); Console.WriteLine(t.getA()); Console.ReadKey(); } To produce the following output: 4 4 Ideally, I would like to do this without writing a wrapper class around the integer. In other words, I think I want pointers in .Net.

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  • How to do manual DI with deep object graphs and many dependencies properly

    - by Fabian
    I believe this questions has been asked in some or the other way but i'm not getting it yet. We do a GWT project and my project leader disallowed to use GIN/Guice as an DI framework (new programmers are not going to understand it, he argued) so I try to do the DI manually. Now I have a problem with deep object graphs. The object hierarchy from the UI looks like this: AppPresenter-DashboardPresenter-GadgetPresenter-GadgetConfigPresenter The GadgetConfigPresenter way down the object hierarchy tree has a few dependencies like CustomerRepository, ProjectRepository, MandatorRepository, etc. So the GadgetPresenter which creates the GadgetConfigPresenter also has these dependencies and so on, up to the entry point of the app which creates the AppPresenter. Is this the way manual DI is supposed to work? doesn't this mean that I create all dependencies at boot time even I don't need them? would a DI framework like GIN/Guice help me here?

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  • reinitialize an object with self.__init__(...)

    - by Kara Jevo
    Could anybody explain whether it is safe to reinitialize an object by calling "self.init(". as shown in the following simplified example? The reason i'm asking is that i couldn't find this method neither in several python books nor in internet. There are some who suggest to list all attributes and set them to initial value one by one. Basically i want to set my object to initial state after it has finished some tasks. class Book(object): def __init__(self,name,author): self.name = name self.author = author self.copies = 5 def reset(self): self.__init__(self.name,self.author) def incrementCopy(self): self.copies += 1 Kite = Book('kite runner','khaled hosseini') print 'initial number of copies:', Kite.copies Kite.incrementCopy() Kite.incrementCopy() Kite.incrementCopy() print '3 copies are added:', Kite.copies Kite.reset() print 'number of copies are reinitialized', Kite.copies initial number of copies: 5 3 copies are added: 8 number of copies are reinitialized 5

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  • javascript "this" points to Window object again

    - by terrani
    Hello, I asked a question on http://stackoverflow.com/questions/2719643/javascript-this-points-to-window-object regarding "this" points to Window object. here is source code var archive = function(){} archive.prototype.action = { test: function(callback){ callback(); }, test2: function(){ console.log(this); } } var oArchive = new archive(); oArchive.action.test(oArchive.action.test2); Tim Down wrote "but that function is then called using callback(), which means it is not called as a method and hence this is the global object". What are differences between calling a function by its actual name and callback() as shown on the source code? How does console.log(this) in test2 points to Window when it is inside archive.action???

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  • Mimic an HTTPRequest and HTTPResponse object in Java

    - by Ankur
    How do I mimic an HTTPServletRequest and HTTPServletResponse object. The reason is I want to test the behaviour of some servlets. I know JUnit probably provides this functionality but I don't know how to use it (I will learn soon) and need to do this reasonably quickly. HTTPServletRequest and HTTPServletResponse are both interfaces so they can't be instantiated. There is a HttpServletRequestWrapper which implements HttpServletRequest but it doesn't seem to have any setParameter() type methods and HttpServletResponse doesn't seem to have any implementing classes at all. How can I test my code by passing a suitable HttpServletRequest object and then checking that the received HttpServletResponse object matches what I expect?

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  • Displaying mysql results as an object?

    - by Michael
    If I have a database with the structure: ___id_____|____value____ 1 | value1 2 | value2 3 | value3 How can I pull data from this MySQL database in PHP and have it formatted like this: Array ( [0] => stdClass Object ( [id] => 1 [value] => value1 ) [1] => stdClass Object ( [id] => 2 [value] => value2 ) [2] => stdClass Object ( [id] => 3 [value] => value3 ) )

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  • jQuery internals: Organization of the jQuery Object

    - by sonofdelphi
    I was going through the source code of jQuery. I'm having trouble understanding the wrapping strategy for the jQuery object. (function( window, undefined ) { // Define a local copy of jQuery var jQuery = function( selector, context ) { // The jQuery object is actually just the init constructor 'enhanced' return new jQuery.fn.init( selector, context ); }, .... .... .... // Expose jQuery to the global object window.jQuery = window.$ = jQuery; })(window); Specifically, what I'm not able to understand stems from the first line. What is the outermost unnamed container function? Why is it required? Why is the container function anonymous? What is the need for the outermost '(' parantheses ?

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  • NHibernate listener/event to replace object before insert/update

    - by vIceBerg
    Hi! I have a Company class which have a collection of Address. Here's my Address class:(written top of my head): public class Address { public string Civic; public string Street; public City City; } This is the City class: public class City { public int Id; public string Name; public string SearchableName{ get { //code } } } Address is persisted in his own table and have a reference to the city's ID. City are also persisted in is own table. The City's SearchableName is used to prevent some mistakes in the city the user type. For example, if the city name is "Montréal", the searchable name will be "montreal". If the city name is "St. John", the searchable name will be "stjohn", etc. It's used mainly to to search and to prevent having multiple cities with a typo in it. When I save an address, I want an listener/event to check if the city is already in the database. If so, cancel the insert and replace the user's city with the database one. I would like the same behavior with updates. I tried this: public bool OnPreInsert(PreInsertEvent @event) { City entity = (@event.Entity as City); if (entity != null) { if (entity.Id == 0) { var city = (from c in @event.Session.Linq<City>() where c.SearchableName == entity.SearchableName select c).SingleOrDefault(); if (city != null) { //don't know what to do here return true; } } } return false; } But if there's already a City in the database, I don't know what to do. @event.Entity is readonly, if I set @event.Entity.Id, I get an "null identifier" exception. I tried to trap insert/update on Address and on Company, but the City if the first one to get inserted (it's logic...) Any thoughts? Thanks

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  • What simple methods are there to wrap a c++ based object model with a COM interface

    - by Rich
    I have a pre-existing c++ object model which represents the business layer tier of an application. I want to be able to expose the object model to applications written in other languages i.e vbscript, VB, javascript etc. I believe the best way of doing this is to wrap the business objects with a COM layer. What fast and effective methods are there for doing this. Any advice, links to practical "How to" documentation would be very much appreciated. Because I'm starting a bounty on this , here's a few extra guidelines for potential bounty hunters :- 1)I've decided on an ATL approach 2)I'm now specifically looking for links to really good "how to and quickly" documentation on wrapping a pre-existing c++ object model to make it useable by a scripting language like javascript 3) Something with small working examples showing me what code needs to be added to what files, e.g what goes into the cpp , idl and hpp/h etc. It' must include an example I can compile test and change to get a better understanding.

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  • How to get all the updates for a Second Life Object (prim) using LIBOMV

    - by sura
    Hi All, In Second Life, I have an avatar and a primitive object that are moving with changing velocity. I use the LIBOMV library to create a text client to Second Life. Using this LIBOMV text client, I am trying to record the update packets of that avatar and object that are being sent to my text client by the server. I get frequent update packets for the avatar as its velocity changes, but I do not get update packets for the object that frequently, although it has a changing velocity. I would like to know whether there is any special setting I should use in order to solve this problem. /Su

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  • How to reference an object in a lower fragment in android

    - by Silas Greenback
    I am trying to build a help screen that is going to go on a mediaplayer. The idea is to put a fragment with a transparent theme on top of the current view. (See How do I create a help overlay like you see in a few Android apps and ICS? for the basic idea). Now, I understand the steps in the mentioned link, but how do I connect the circles and arrows and paragraphs next to each one (explaining what each one was) to the lower object? Example, I have an object: R.id.music_button and I want there to be and arrow that points to music button. Trying to support as many devices as we do it will be very difficult to just draw a few pictures as part of the top layout and expect them to line up. Again, how do I reference an object on a fragment below the top level? Thanks

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  • How to create Bitmap object from a Graphics object ?

    - by vi.su.
    How to create Bitmap object from a Graphics object ? I would like to read pixels from my Graphics object. for example, like, System.Drawing.BitMap.GetPixel(). I am trying to find out empty area (all white, or of any colour) inside a pdf document, to write some graphics / image. I have tried like this, but it is not working. why the following code is not working as expected ? // // System.Drawing.Bitmap // System.Drawing.Graphics // Bitmap b = new Bitmap(width, height, graphics); // // In this case, for any (i, j) values, Bitmap.GetPixel returns 0 // int rgb = b.GetPixel(i, j).ToArgb(); ( posting this question again in .net-only context, removing other library dependencies )

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  • Mandatory Parameters in Request object (WCF)

    - by Martin Moser
    lHi, I'm currently writing a WCF service. One of those methods get's a request object and returns a response object. In the request there are a couple of value-type members. Is there a way to define members are mandatory in the declarative way? I'm in an early stage of development and I don't want to start with versioning now. In addition I don't want to have method sig with 25 parameters, therefore I created the request object. The problem I have is that due to the value-types, I can never be sure if the consumer of the service intended to have the default value in there, or it was just by lazyness. On consumer side you don't easily detect that you probably missed that property. So I would like to have something that forces the caller of the service to provide an value, and if not he ideally get's a compile-time error. any ideas? tia, Martin

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  • Suggestions on how to track tag count for a particular object

    - by Robin Fisher
    Hi, I'm looking for suggestions on how to track the number of tags associated with a particular object in Rails. I'm using acts_as_taggable_on and it's working fine. What I would like to be able to do is search for all objects that have no tags, preferably through a scope i.e. Object.untagged.all My first thought was to use an after_save callback to update an attribute called "taggings_count" in my model: def update_taggings_count self.taggings_count = self.tag_list.size self.save end Unfortunately, this does the obvious thing of putting me in an infinite loop. I need to use an after_save callback because the tag_list is not updated until the main object is saved. Would appreciate any suggestions as I'm on the verge of rolling my own tagging system. Regards Robin

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  • Is re-using a Command and Connection object in ado.net a legitimate way of reducing new object creat

    - by Neil Trodden
    The current way our application is written, involves creating a new connection and command object in every method that access our sqlite db. Considering we need it to run on a WM5 device, that is leading to hideous performance. Our plan is to use just one connection object per-thread but it's also occurred to us to use one global command object per-thread too. The benefit of this is it reduces the overhead on the garbage collector created by instantiating objects all over the place. I can't find any advice against doing this but wondered if anyone can answer definitively if this is a good or bad thing to do, and why?

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  • Getting the most recent post based on date

    - by camcim
    Hi guys, How do I go about displaying the most recent post when I have two tables, both containing a column called creation_date This would be simple if all I had to do was get the most recent post based on posts created_on value however if a post contains replies I need to factor this into the equation. If a post has a more recent reply I want to get the replies created_on value but also get the posts post_id and subject. The posts table structure: CREATE TABLE `posts` ( `post_id` bigint(20) unsigned NOT NULL auto_increment, `cat_id` bigint(20) NOT NULL, `user_id` bigint(20) NOT NULL, `subject` tinytext NOT NULL, `comments` text NOT NULL, `created_on` datetime NOT NULL, `status` varchar(10) NOT NULL default 'INACTIVE', `private_post` varchar(10) NOT NULL default 'PUBLIC', `db_location` varchar(10) NOT NULL, PRIMARY KEY (`post_id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=7 ; The replies table structure: CREATE TABLE `replies` ( `reply_id` bigint(20) unsigned NOT NULL auto_increment, `post_id` bigint(20) NOT NULL, `user_id` bigint(20) NOT NULL, `comments` text NOT NULL, `created_on` datetime NOT NULL, `notify` varchar(5) NOT NULL default 'YES', `status` varchar(10) NOT NULL default 'INACTIVE', `db_location` varchar(10) NOT NULL, PRIMARY KEY (`reply_id`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 AUTO_INCREMENT=5 ; Here is my query so far. I've removed my attempt of extracting the dates. $strQuery = "SELECT posts.post_id, posts.created_on, replies.created_on, posts.subject "; $strQuery = $strQuery."FROM posts ,replies "; $strQuery = $strQuery."WHERE posts.post_id = replies.post_id "; $strQuery = $strQuery."AND posts.cat_id = '".$row->cat_id."'";

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  • Bullet physics engine, how to freeze an object?

    - by Markus
    Using Bullet 2.76 I'm trying to freeze an object (rigid body) so that it instantly stops moving, but still responds to collisions. I tried setting it's activation state to DISABLE_SIMULATION, but then it's virtually nonexistent to other objects. Furthermore, if objects "collide" with it when it's disabled, strange things begin to happen (object's falling through static bodies, etc.) I suppose, temporarily converting it to a static rigid body could work, but is there an existing "native" way to achieve this on Bullet's side? Edit: Is there a way to turn off gravity for a specific object?

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  • Using polyfit to predict where the object falls ?

    - by ZaZu
    Hi there, I have information of an object being thrown at a parabolic pattern. There are 30 images in total taken at specific intervals from the start position till the end. Now I have managed to extract the x,y coordinates of the object being thrown in all 30 images... I think that using polyfit (or maybe polyval ? ) may help me predict where the object will fall after the first 15 images ... I just want to know, how can polyfit be used with the 30 x,y coordinates I have ? ( I have a loop to extract each image from a mat file 1 row at a time until 30 .. and then plot that image .. so should I use polyfit in the same loop before/after the plot ??? Any ideas ?? Thanks !

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  • Hibernate does not allow an embedded object with an int field to be null?

    - by Jason Novak
    Hibernate does not allow me to persist an object that contains an null embedded object with an integer field. For example, if I have a class called Thing that looks like this @Entity public class Thing { @Id public String id; public Part part; } where Part is an embeddable class that looks like this @Embeddable public class Part { public String a; public int b; } then trying to persist a Thing object with a null Part causes Hibernate to throw an Exception. In particular, this code Thing th = new Thing(); th.id = "thing.1"; th.part = null; session.saveOrUpdate(th); causes Hibernate to throw this Exception org.hibernate.PropertyValueException: not-null property references a null or transient value: com.ace.moab.api.jobs.Thing.part My guess is that this is happening because Part is an embedded class and so Part.a and Part.b are simply columns in the Thing database table. Since the Thing.part is null Hibernate wants to set the Part.a and Part.b column values to null for the row for thing.1. However, Part.b is an integer and Hibernate will not allow integer columns in the database to be null. This is what causes the Exception, right? So I am looking for workarounds for this problem. I noticed making Part.b an Integer instead of an int seems to work, but for reasons I won't bore you with this is not a good option for us. Thanks!

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