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  • mysql eliminate responses under certain condition with join

    - by Dustin
    Forgive me if this is an easy question. I teach classes and want to be able to select those students who have taken one class, but not another class. I have two tables: lessons_slots which is the table for every class such as: -------------------- -ID name slots- -1 basics 10 - -2 advanced 10 - -3 basics 10 - --------------------- The other table is class_roll, which holds enrollment info, such as: -------------------- -sID classid firstname lastname- -1 1 Jo Schmo -2 1 Person Two ... -13 2 Jo Schmo --------------------- What I want to do, I select everyone who has not had the advanced class (for example). I've tried doing SELECT * FROM lessons_slots LEFT JOIN class_roll ON lessons_slots.ID = class_roll.classid WHERE lessons_slots.name != 'advanced' But that doesn't work. Any ideas?

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  • creating new instance fails PHP

    - by as3isolib
    I am relatively new to PHP and having some decent success however I am running into this issue: If I try to create a new instance of the class GenericEntryVO, I get a 500 error with little to no helpful error information. However, if I use a generic object as the result, I get no errors. I'd like to be able to cast this object as a GenericEntryVO as I am using AMFPHP to communicate serialize data with a Flex client. I've read a few different ways to create constructors in PHP but the typical 'public function Foo()' for a class Foo was recommended for PHP 5.4.4 //in my EntryService.php class public function getEntryByID($id) { $link = mysqli_connect("localhost", "root", "root", "BabyTrackingAppDB"); if (mysqli_connect_errno()) { printf("Connect failed: %s\n", mysqli_connect_error()); exit(); } $query = "SELECT * FROM Entries WHERE id = '$id' LIMIT 1"; if ($result = mysqli_query($link, $query)) { // $entry = new GenericEntryVO(); this is where the problem lies! while ($row = mysqli_fetch_row($result)) { $entry->id = $row[0]; $entry->entryType = $row[1]; $entry->title = $row[2]; $entry->description = $row[3]; $entry->value = $row[4]; $entry->created = $row[5]; $entry->updated = $row[6]; } } mysqli_free_result($result); mysqli_close($link); return $entry; } //my GenericEntryVO.php class <?php class GenericEntryVO { public function __construct() { } public $id; public $title; public $entryType; public $description; public $value; public $created; public $updated; // public $properties; } ?>

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  • How to pass data to a C++0x lambda function that will run in a different thread?

    - by Dimitri C.
    In our company we've written a library function to call a function asynchronously in a separate thread. It works using a combination of inheritance and template magic. The client code looks as follows: DemoThread thread; std::string stringToPassByValue = "The string to pass by value"; AsyncCall(thread, &DemoThread::SomeFunction, stringToPassByValue); Since the introduction of lambda functions I'd like to use it in combination with lambda functions. I'd like to write the following client code: DemoThread thread; std::string stringToPassByValue = "The string to pass by value"; AsyncCall(thread, [=]() { const std::string someCopy = stringToPassByValue; }); Now, with the Visual C++ 2010 this code doesn't work. What happens is that the stringToPassByValue is not copied. Instead the "capture by value" feature passes the data by reference. The result is that if the function is executed after stringToPassByValue has gone out of scope, the application crashes as its destructor is called already. So I wonder: is it possible to pass data to a lambda function as a copy? Note: One possible solution would be to modify our framework to pass the data in the lambda parameter declaration list, as follows: DemoThread thread; std::string stringToPassByValue = "The string to pass by value"; AsyncCall(thread, [=](const std::string stringPassedByValue) { const std::string someCopy = stringPassedByValue; } , stringToPassByValue); However, this solution is so verbose that our original function pointer solution is both shorter and easier to read. Update: The full implementation of AsyncCall is too big to post here. In short, what happens is that the AsyncCall template function instantiates a template class holding the lambda function. This class is derived from a base class that contains a virtual Execute() function, and upon an AsyncCall() call, the function call class is put on a call queue. A different thread then executes the queued calls by calling the virtual Execute() function, which is polymorphically dispatched to the template class which then executes the lambda function.

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  • Regex Problem(C#)

    - by oraclee
    Hi all; Html Code: <TD style="DISPLAY: none">999999999</TD> <TD class=CLS1 >Name</TD> <TD class=BLACA>271229</TD> <TD>220</TD> <TD>343,23</TD> <TD>23,0</TD> <TD>222,00</TD> <TD>33222,8</TD> <TD class=blacl>0</TD> <TD class=black>0</TD> <TD>3433</TD> <TD>40</TD> i need td in value how to make csharp, i wanna string array; 999999999 Name 271229 220 pls help

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  • Instance where embedded C++ compilers don't support multiple inheritance?

    - by Nathan
    I read a bit about a previous attempt to make a C++ standard for embedded platforms where they specifically said multiple inheritance was bad and thus not supported. From what I understand, this was never implemented as a mainstream thing and most embedded C++ compilers support most standard C++ constructs. Are there cases where a compiler on a current embedded platform (i.e. something not more than a few years old) absolutely does not support multiple inheritance? I don't really want to do multiple inheritance in a sense where I have a child with two full implementations of a class. What I am most interested in is inheriting from a single implementation of a class and then also inheriting one or more pure virtual classes as interfaces only. This is roughly equivalent to Java/.Net where I can extend only one class but implement as many interfaces as I need. In C++ this is all done through multiple inheritance rather than being able to specifically define an interface and declare a class implements it.

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  • How to implement "select sum()" in Grails

    - by xain
    I have a relationship like this: class E { string name hasMany = [me:ME] } class M { float price } class ME { E e M m int quantity } And I'd hate to iterate to achieve this: "obtain the sum of the quantity in ME times the price of the corresponding M for a given E". Any hints on how to implement it using GORM/HQL ? Thanks in advance

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  • C# -Fluent interface implementation Help

    - by nettguy
    I am implementing the following piece of code using Fluent Interface design in C# 3.0. The code is working fine. public interface ITrainable { ITrainable AddSkill(string _skill); } public interface ISearchSkill { ISearchSkill SearchSkill(SoftwareEngineer emp,string[] _skills); } public abstract class Person { public Person(){} protected string Name { get; set; } } public class SoftwareEngineer:Person,ITrainable { protected internal List<string> skillSet { get; set; } public SoftwareEngineer() { } public SoftwareEngineer(string name) { Name=name; skillSet = new List<string>(); } public ITrainable AddSkill(string _skill) { skillSet.Add(_skill); return this; } } public class HRExecutive :Person,ISearchSkill { SoftwareEngineer _employee; public HRExecutive() { _employee=new SoftwareEngineer(); } public ISearchSkill SearchSkill(SoftwareEngineer _employee,string[] skills) { this._employee= _employee; foreach (string _skill in skills) { if (_employee.skillSet.Contains(_skill)) { Console.WriteLine(Name + " is trained on " + _skill); } else { Console.WriteLine(Name + " is not trained on " + _skill); } } return this; } } Execution SoftwareEngineer emp1 = new SoftwareEngineer("JonSkeet"); emp1.AddSkill("java").AddSkill("C#").AddSkill("F#"); HRExecutive hr = new HRExecutive(); hr.SearchSkill(emp1, new string[] { "java", "C#" }). SearchSkill(emp1, new string[] { "Oracle", "F#" }); Question : I don't want the skillSet of SoftwareEngineer being accessed by some XXX class.It could be accessed by limited classes.But protected internal List<string> skillSet { get; set; } is the only option (i think) i can declare in order to access the skillSet from HRExecutive.If i do so other XXX class can still access it. How to rewrite the code to prevent it?

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  • How to align floated elements such that their bottoms match

    - by AJM
    I'm writing a web page where I show a title and a date over some text. My HTML: <div class="post"> <h2>Post 1</h2> <span class="date">February 28, 2011</span> <div class="post-content"> ... </div> </div> My css: .post h2 { float: left; } .date { float: right; } .post-content { clear: both; } What I want to do is vertically align the title and date such that their bottoms match. Right now they don't: I tried wrapping the two text elements in a div, setting the div's position to relative, and using absolute positioning on the two text elements (and taking out the float declarations). That didn't work because the top margin is not preserved due to the wrapper div collapsing, even though I gave it a clearfix class.

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  • How can I "override" deepcopy in Python?

    - by Az
    Hi there, I'd like to override __deepcopy__ for a given SQLAlchemy-mapped class such that it ignores any SQLA attributes but deepcopies everything else that's part of the class. I'm not particularly familiar with overriding any of Python's built-in objects in particular but I've got some idea as to what I want. Let's just make a very simple class User that's mapped using SQLA. class User(object): def __init__(self, user_id, name): self.user_id = user_id self.name = name I've used dir() to see, before and after mapping, what SQLAlchemy-specific attributes there are and I've found _sa_class_manager and _sa_instance_state. Provided those are the only ones how would I ignore that when defining __deepcopy__? Also, are there any attributes the SQLA injects into the mapped object? (I asked this in a previous question (as an edit a few days after I selected an answer to the main question, though) but I think I missed the train there. Apologies for that.)

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  • text-transform cannot change/be overwritten? (css)

    - by Radek
    I am studying css and I do not understand why some OTHER text and line 2 has red underline effect on them. I thought I either changed it for class others or reset it to none for class line2 I tried `text-decoration:none' for both .line2 and .others and the text was still red underlined. <html> <head> <style type="text/css"> .line {color:red; text-transform:uppercase; text-decoration:underline;} .line2 {color:blue; text-transform:none;} .others {color:black; text-transform:lowercase; text-decoration:blink; font-weight:bold;} </style> </head> <body> <div class='line'> line 1 <div class='others'><BR>some OTHER text<BR></DIV> <div class='line2'> <BR>line 2 </div> </div> </body> </html>

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  • NHibernate: How is identity Id updated when saving a transient instance?

    - by bretddog
    If I use session-per-transaction and call: session.SaveOrUpdate(entity) corrected: session.SaveOrUpdateCopy(entity) ..and entity is a transient instance with identity-Id=0. Shall the above line automatically update the Id of the entity, and make the instance persistent? Or should it do so on transaction.Commit? Or do I have to somehow code that explicitly? Obviously the Id of the database row (new, since transient) is autogenerated and saved as some number, but I'm talking about the actual parameter instance here. Which is the business logic instance. EDIT Mappings: public class StoreMap : ClassMap<Store> { public StoreMap() { Id(x => x.Id).GeneratedBy.Identity(); Map(x => x.Name); HasMany(x => x.Staff) // 1:m .Cascade.All(); HasManyToMany(x => x.Products) // m:m .Cascade.All() .Table("StoreProduct"); } } public class EmployeeMap : ClassMap<Employee> { public EmployeeMap() { Id(x => x.Id).GeneratedBy.Identity(); Map(x => x.FirstName); Map(x => x.LastName); References(x => x.Store); // m:1 } } public class ProductMap : ClassMap<Product> { public ProductMap() { Id(x => x.Id).GeneratedBy.Identity(); Map(x => x.Name).Length(20); Map(x => x.Price).CustomSqlType("decimal").Precision(9).Scale(2); HasManyToMany(x => x.StoresStockedIn) .Cascade.All() .Inverse() .Table("StoreProduct"); } } EDIT2 Class definitions: public class Store { public int Id { get; private set; } public string Name { get; set; } public IList<Product> Products { get; set; } public IList<Employee> Staff { get; set; } public Store() { Products = new List<Product>(); Staff = new List<Employee>(); } // AddProduct & AddEmployee is required. "NH needs you to set both sides before // it will save correctly" public void AddProduct(Product product) { product.StoresStockedIn.Add(this); Products.Add(product); } public void AddEmployee(Employee employee) { employee.Store = this; Staff.Add(employee); } } public class Employee { public int Id { get; private set; } public string FirstName { get; set; } public string LastName { get; set; } public Store Store { get; set; } } public class Product { public int Id { get; private set; } public string Name { get; set; } public decimal Price { get; set; } public IList<Store> StoresStockedIn { get; private set; } }

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  • PHP Value Object auto create

    - by JonoB
    Assume that I have a class value object defined in php, where each variable in the class is defined. Something like: class UserVO { public $id; public $name; } I now have a function in another class, which is expecting an array ($data). function save_user($data) { //run code to save the user } How do I tell php that the $data parameter should be typed as a UserVO? I could then have code completion to do something like: $something = $data->id; //typed as UserVO.id $else = $data->name; //typed as UserVO.name I'm guessing something like the following, but this obviously doesnt work $my_var = $data as new userVO();

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  • C++ IDE for Linux with smart reference searching

    - by Dmitry Yudakov
    Is there an IDE supporting C++ with REALLY smart searching of references? By 'reference' I mean usage of a class (or its member), variable, function in the whole Project or Workspace. There's lots of IDE providing it. Some of them seem just to search for the text with same name giving lots of stuff, others are smarter and check the context (like class boundaries, namespace) but aren't accurate enough. The best I've tried so far was Visual SlickEdit, but still there's more to wish. class C1 { int foo; }; class C2 { int foo; }; For example in this situation when searching for C1::foo references I don't want C2::foo to be shown too. So, is there an IDE that would be so smart?

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  • Ads in whole app iPhone problem

    - by lars
    I am using mobclix together with admob. The code is to big to add it in all classes. So i created a new class: Ads Everytime i want an ad in a view, i have to send the view to the ad class: - (void)initAd:(UIView *) pView { NSLog(@"ads init"); self.loadedView = pView; ..... To create an ad in a class: Ad* ad = [Ads new]; [ad initAd:self.view]; I dont know if thats the right way. I have to create a new Ads object everytime i change a view (or class). Is there a way to always have an Ads instance running, or is there another better way? Thanks alot!!

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  • Remove some tags in jquery

    - by user201140
    I would like to use jquery to remove some tags inside mainclass, so that this - <div class='mainclass'> <div class='inclass'> <a href='#'>Some text</a> </div> </div> Becomes this - <div class='mainclass'> Some text </div> Thanks in advance.

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  • Is a many-to-many relationship with extra fields the right tool for my job?

    - by whichhand
    Previously had a go at asking a more specific version of this question, but had trouble articulating what my question was. On reflection that made me doubt if my chosen solution was correct for the problem, so this time I will explain the problem and ask if a) I am on the right track and b) if there is a way around my current brick wall. I am currently building a web interface to enable an existing database to be interrogated by (a small number of) users. Sticking with the analogy from the docs, I have models that look something like this: class Musician(models.Model): first_name = models.CharField(max_length=50) last_name = models.CharField(max_length=50) dob = models.DateField() class Album(models.Model): artist = models.ForeignKey(Musician) name = models.CharField(max_length=100) class Instrument(models.Model): artist = models.ForeignKey(Musician) name = models.CharField(max_length=100) Where I have one central table (Musician) and several tables of associated data that are related by either ForeignKey or OneToOneFields. Users interact with the database by creating filtering criteria to select a subset of Musicians based on data the data on the main or related tables. Likewise, the users can then select what piece of data is used to rank results that are presented to them. The results are then viewed initially as a 2 dimensional table with a single row per Musician with selected data fields (or aggregates) in each column. To give you some idea of scale, the database has ~5,000 Musicians with around 20 fields of related data. Up to here is fine and I have a working implementation. However, it is important that I have the ability for a given user to upload there own annotation data sets (more than one) and then filter and order on these in the same way they can with the existing data. The way I had tried to do this was to add the models: class UserDataSets(models.Model): user = models.ForeignKey(User) name = models.CharField(max_length=100) description = models.CharField(max_length=64) results = models.ManyToManyField(Musician, through='UserData') class UserData(models.Model): artist = models.ForeignKey(Musician) dataset = models.ForeignKey(UserDataSets) score = models.IntegerField() class Meta: unique_together = (("artist", "dataset"),) I have a simple upload mechanism enabling users to upload a data set file that consists of 1 to 1 relationship between a Musician and their "score". Within a given user dataset each artist will be unique, but different datasets are independent from each other and will often contain entries for the same musician. This worked fine for displaying the data, starting from a given artist I can do something like this: artist = Musician.objects.get(pk=1) dataset = UserDataSets.objects.get(pk=5) print artist.userdata_set.get(dataset=dataset.pk) However, this approach fell over when I came to implement the filtering and ordering of query set of musicians based on the data contained in a single user data set. For example, I could easily order the query set based on all of the data in the UserData table like this: artists = Musician.objects.all().order_by(userdata__score) But that does not help me order by the results of a given single user dataset. Likewise I need to be able to filter the query set based on the "scores" from different user data sets (eg find all musicians with a score 5 in dataset1 and < 2 in dataset2). Is there a way of doing this, or am I going about the whole thing wrong?

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  • C++ app fails to initialize (0xc0000005), when using C# dll

    - by Simon
    Hi, I have a C# DLL, which I call from a native C++ programm. As I use Qt and /clr compiler option did not work I followed this tutorial for a bridge. So I have a VS2008 project (compiled with /clr), which links to the C# DLL and contains the bridge class and the native class, which exposes interfaces to my C++ programm. Another VS2008 project (no .net stuff) calls the native class (statically linked). I had some issues, but now the programm at least compiles. However, if I try to run this programm, I get a (0xc0000005) error on initialization, when I try to use the native class. As this happens on initialization, I don't even see, which DLLs fail to initialize. All DLLs should be in the right place. Any hints? Thank you.

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  • Using group_by with fields_for and accepts_nested_attributes_for

    - by Derek
    I have a the following rails models: class Release < ActiveRecord::Base has_many :release_questionnaires, :dependent => :destroy accepts_nested_attributes_for :release_questionnaires ... end class class ReleaseQuestionnaire < ActiveRecord::Base belongs_to :release belongs_to :milestone ... end class In my view code, I have the following form. <% form_for @release, ... do |f| %> ... <table class="questionnaires"> <% f.fields_for :release_questionnaires, @release.release_questionnaires.sort_by{|ra| ra.questionnaire.name} do |builder| %> ... <% end %> </table> <% end %> This works and allows me to view and edit the questionnaires as desired. However, I have an additional requirement to break the questionnaires out into their own tables grouped by the milestone they are associated to, rather than in a single table. It appears as though the group_by method is design to accomplish this, but I cannot get it to work as desired inside the tag. It may be that I'm missing something obvious, as I am a beginner... Any help is appreciated.

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  • Circular reference problem Singleton

    - by Ismail
    I'm trying to creating a Singleton class like below where MyRepository lies in separate DAL project. It's causing me a circular reference problem because GetMySingleTon() method returns MySingleTon class and needs its access. Same way I need MyRepository access in constructor of MySingleTon class. public class MySingleTon { static MySingleTon() { if (Instance == null) { MyRepository rep = new MyRepository(); Instance = rep.GetMySingleTon(); } } public static MySingleTon Instance { get; private set; } public string prop1 { get; set; } public string prop2 { get; set; } }

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  • How can I configure different worker pools using celery?

    - by Chris R
    I need to deploy a queued execution service with (generally) the following three classes of worker: A periodic, low-priority job class that takes a long time and can be processed serially; these jobs should only use 0..2 workers in the system at most. A periodic, deadline-sensitive job class that take a short to medium amount of time (say, topping out at 5 minutes) An ad-hoc job class, that is higher priority than #1, but can interleave with #2. Any workers from class #2 that are inactive when this type of job comes in should handle it, without ever starving the pool of workers for #2 All three job classes are the same task, the only difference between them is how they're requested; they'll take the same input and generate the same output, but each one has different performance guarantees. How can I implement this using celery?

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  • Is there a g++ equivalent to Visual Studio's __declspec(novtable)?

    - by ceretullis
    Is there a g++ equivalent to Visual Studio's __declspec(novtable) argument? Basically, in a pure virtual base class the __declspec(novtable) argument can be used to suppress the creation of a vtable for the base class as well as vtable initialization/deinitialization code in the contstructor/destructor respectively. E.g., class __declspec(novtable) PureVirtualBaseClass { public: PureVirtualBaseClass(){} virtual ~PureVirtualBaseClass() = 0; }; See Paul DiLascia's article for more info. Also see my related question.

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  • How to treat Base* pointer as Derived<T>* pointer?

    - by dehmann
    I would like to store pointers to a Base class in a vector, but then use them as function arguments where they act as a specific class, see here: #include <iostream> #include <vector> class Base {}; template<class T> class Derived : public Base {}; void Foo(Derived<int>* d) { std::cerr << "Processing int" << std::endl; } void Foo(Derived<double>* d) { std::cerr << "Processing double" << std::endl; } int main() { std::vector<Base*> vec; vec.push_back(new Derived<int>()); vec.push_back(new Derived<double>()); Foo(vec[0]); Foo(vec[1]); delete vec[0]; delete vec[1]; return 0; } This doesn't compile: error: call of overloaded 'Foo(Base*&)' is ambiguous Is it possible to make it work? I need to process the elements of the vector differently, according to their int, double, etc. types.

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  • What reasons are there to place member functions before member variables or vice/versa?

    - by Cory Klein
    Given a class, what reasoning is there for either of the two following code styles? Style A: class Foo { private: doWork(); int bar; } Style B: class Foo { private: int bar; doWork(); } For me, they are a tie. I like Style A because the member variables feel more fine-grained, and thus would appear past the more general member functions. However, I also like Style B, because the member variables seem to determine, in a OOP-style way, what the class is representing. Are there other things worth considering when choosing between these two styles?

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  • I cant able to remove a row from a table while running through a loop

    - by Vibin Jith
    I am iterating through the table rows . if the row row is null I just want to remove the row. it shows an error Public Sub RemoveBlankRow(ByVal MyDataTable As DataTable) Try Dim MyRowStr As String = String.Empty For Each MyRow As DataRow In MyDataTable.Rows MyRowStr = "" For Each MyCellText As Object In MyRow.ItemArray MyRowStr = MyRowStr + MyCellText.ToString Next MyRowStr = Replace(MyRowStr, "0", " ") MyRowStr = Replace(MyRowStr, ".", " ") If MyRowStr.Trim = String.Empty Then MyDataTable.Rows.Remove(MyRow) End If Next Catch ex As Exception End Try End Sub How to overcome this issue?

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