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  • trying to install SQL 2008 on WIndows 2008 server R2

    - by Nezdet
    Hi I was trying to install MSSQL 2008 server on WIndows 208 server R2 Standard Machine, but I got This message: Program Compatibility Assistant, And that I should apply SQL server 2008 SP 1 I don't get it? Why Dosen't it not work with this version I have? How should I solve this problem?

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  • Mouse wheel not scrolling in JDialog

    - by Iulian Serbanoiu
    Hello, I'm facing a frustrating issue. I have an application where the scroll wheel doesn't work in a JDialog class. Here's the code: import javax.swing.*; import java.awt.event.*; public class Failtest extends JFrame { public static void main(String[] args) { new Failtest(); } public Failtest() { super(); setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); setTitle("FRAME"); JScrollPane sp1 = new JScrollPane(getNewList()); add(sp1); setSize(150, 150); setVisible(true); JDialog d = new JDialog(this, false);// NOT WORKING //JDialog d = new JDialog((JFrame)null, false); // NOT WORKING //JDialog d = new JDialog((JDialog)null, false);// WORKING - WHY? d.setTitle("DIALOG"); d.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE); JScrollPane sp = new JScrollPane(getNewList()); d.add(sp); d.setSize(150, 150); d.setVisible(true); } public JList getNewList() { String objs[] = new String[30]; for(int i=0; i<objs.length; i++) { objs[i] = "Item "+i; } JList l = new JList(objs); return l; } } I found a solution which is present as a comment in the java code - the constructor receiving a (JDialog)null parameter. Can someone enlighten me? My opinion is that this is a java bug. Tested on Windows XP-SP3 with 1 JDK and 2 JREs: D:\Program Files\Java\jdk1.6.0_17\bin>javac -version javac 1.6.0_17 D:\Program Files\Java\jdk1.6.0_17\bin>java -version java version "1.6.0_17" Java(TM) SE Runtime Environment (build 1.6.0_17-b04) Java HotSpot(TM) Client VM (build 14.3-b01, mixed mode, sharing) D:\Program Files\Java\jdk1.6.0_17\bin>cd .. D:\Program Files\Java\jdk1.6.0_17>java -version java version "1.6.0_18" Java(TM) SE Runtime Environment (build 1.6.0_18-b07) Java HotSpot(TM) Client VM (build 16.0-b13, mixed mode, sharing) Thank you in advance, Iulian Serbanoiu PS: The problem is not new - the code is taken from a forum (here) where this problem was also mentioned - but no solutions to it (yet)

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  • WPF Binding.Stringformat ignored

    - by John
    With .NET 3.5 SP 1 I checked out this blog and followed instructions, however the StringFormat parameter still gets ignored. Any possible reasons? To be sure: the datatype that are involved are DateTime, double, int. So the formatting SHOULD work, but it's not. Any clues why?

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  • ssL HTTPS for windows mobile 6::unable to read transport connection

    - by Santhosh
    Hi am trying Https ssl connection in my C# application...i am getting "Unable to read transport connection" for the line WebResponse response = (HttpWebResponse)request.GetResponse(); I am forcing Certificate to be accepted ServicePointManager.CertificatePolicy = new MyPolicy(); public class MyPolicy : ICertificatePolicy { public bool CheckValidationResult(ServicePoint sp, X509Certificate cert, WebRequest req, int problem) { return true; } } Working fine in WM5 may i plz know the wat is goin wrong?plz thanks in advance

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  • SOAPUI: Document Type Webservices Testing.

    - by Neal Johnson
    Hi , I am new to SOAP UI usage. I would like to test one of the webservices generated using weblogic 8.1 SP 6. The webservice is a document type webservice. Is there any way to test this webservice using SOAP UI ?? Or is there any tool which helps to test document type webservices?? Thanks in advance.

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  • Compilation problems with vector<auto_ptr<> >

    - by petersohn
    Consider the following code: #include <iostream> #include <memory> #include <vector> using namespace std; struct A { int a; A(int a_):a(a_) {} }; int main() { vector<auto_ptr<A> > as; for (int i = 0; i < 10; i++) { auto_ptr<A> a(new A(i)); as.push_back(a); } for (vector<auto_ptr<A> >::iterator it = as.begin(); it != as.end(); ++it) cout << (*it)->a << endl; } When trying to compile it, I get the following obscure compiler error from g++: g++ -O0 -g3 -Wall -c -fmessage-length=0 -MMD -MP -MF"src/proba.d" -MT"src/proba.d" -o"src/proba.o" "../src/proba.cpp" /usr/include/c++/4.1.2/ext/new_allocator.h: In member function ‘void __gnu_cxx::new_allocator<_Tp>::construct(_Tp*, const _Tp&) [with _Tp = std::auto_ptr<A>]’: /usr/include/c++/4.1.2/bits/stl_vector.h:606: instantiated from ‘void std::vector<_Tp, _Alloc>::push_back(const _Tp&) [with _Tp = std::auto_ptr<A>, _Alloc = std::allocator<std::auto_ptr<A> >]’ ../src/proba.cpp:19: instantiated from here /usr/include/c++/4.1.2/ext/new_allocator.h:104: error: passing ‘const std::auto_ptr<A>’ as ‘this’ argument of ‘std::auto_ptr<_Tp>::operator std::auto_ptr_ref<_Tp1>() [with _Tp1 = A, _Tp = A]’ discards qualifiers /usr/include/c++/4.1.2/bits/vector.tcc: In member function ‘void std::vector<_Tp, _Alloc>::_M_insert_aux(__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >, const _Tp&) [with _Tp = std::auto_ptr<A>, _Alloc = std::allocator<std::auto_ptr<A> >]’: /usr/include/c++/4.1.2/bits/stl_vector.h:610: instantiated from ‘void std::vector<_Tp, _Alloc>::push_back(const _Tp&) [with _Tp = std::auto_ptr<A>, _Alloc = std::allocator<std::auto_ptr<A> >]’ ../src/proba.cpp:19: instantiated from here /usr/include/c++/4.1.2/bits/vector.tcc:256: error: passing ‘const std::auto_ptr<A>’ as ‘this’ argument of ‘std::auto_ptr<_Tp>::operator std::auto_ptr_ref<_Tp1>() [with _Tp1 = A, _Tp = A]’ discards qualifiers /usr/include/c++/4.1.2/bits/stl_construct.h: In function ‘void std::_Construct(_T1*, const _T2&) [with _T1 = std::auto_ptr<A>, _T2 = std::auto_ptr<A>]’: /usr/include/c++/4.1.2/bits/stl_uninitialized.h:86: instantiated from ‘_ForwardIterator std::__uninitialized_copy_aux(_InputIterator, _InputIterator, _ForwardIterator, __false_type) [with _InputIterator = __gnu_cxx::__normal_iterator<std::auto_ptr<A>*, std::vector<std::auto_ptr<A>, std::allocator<std::auto_ptr<A> > > >, _ForwardIterator = __gnu_cxx::__normal_iterator<std::auto_ptr<A>*, std::vector<std::auto_ptr<A>, std::allocator<std::auto_ptr<A> > > >]’ /usr/include/c++/4.1.2/bits/stl_uninitialized.h:113: instantiated from ‘_ForwardIterator std::uninitialized_copy(_InputIterator, _InputIterator, _ForwardIterator) [with _InputIterator = __gnu_cxx::__normal_iterator<std::auto_ptr<A>*, std::vector<std::auto_ptr<A>, std::allocator<std::auto_ptr<A> > > >, _ForwardIterator = __gnu_cxx::__normal_iterator<std::auto_ptr<A>*, std::vector<std::auto_ptr<A>, std::allocator<std::auto_ptr<A> > > >]’ /usr/include/c++/4.1.2/bits/stl_uninitialized.h:254: instantiated from ‘_ForwardIterator std::__uninitialized_copy_a(_InputIterator, _InputIterator, _ForwardIterator, std::allocator<_Tp>) [with _InputIterator = __gnu_cxx::__normal_iterator<std::auto_ptr<A>*, std::vector<std::auto_ptr<A>, std::allocator<std::auto_ptr<A> > > >, _ForwardIterator = __gnu_cxx::__normal_iterator<std::auto_ptr<A>*, std::vector<std::auto_ptr<A>, std::allocator<std::auto_ptr<A> > > >, _Tp = std::auto_ptr<A>]’ /usr/include/c++/4.1.2/bits/vector.tcc:279: instantiated from ‘void std::vector<_Tp, _Alloc>::_M_insert_aux(__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >, const _Tp&) [with _Tp = std::auto_ptr<A>, _Alloc = std::allocator<std::auto_ptr<A> >]’ /usr/include/c++/4.1.2/bits/stl_vector.h:610: instantiated from ‘void std::vector<_Tp, _Alloc>::push_back(const _Tp&) [with _Tp = std::auto_ptr<A>, _Alloc = std::allocator<std::auto_ptr<A> >]’ ../src/proba.cpp:19: instantiated from here /usr/include/c++/4.1.2/bits/stl_construct.h:81: error: passing ‘const std::auto_ptr<A>’ as ‘this’ argument of ‘std::auto_ptr<_Tp>::operator std::auto_ptr_ref<_Tp1>() [with _Tp1 = A, _Tp = A]’ discards qualifiers make: *** [src/proba.o] Error 1 It seems to me that there is some kind of problem with consts here. Does this mean that auto_ptr can't be used in vectors?

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  • Why is my boot loader's stack segment at 0x3FF (end of Real Mode IVT)?

    - by Laurimann
    Title says it all. "address 0x500 is the last one used by the BIOS" - en.wikipedia.org/wiki/Master_boot_record "00000000-000003FF Real Mode IVT (Interrupt Vector Table)" - wiki.osdev.org/Memory_Map_%28x86%29 So can you tell me why NASM places my .com file's stack pointer to 0x3FF while my instruction pointer starts at 0x7c00? To me the most intuitive place for SP would be right below 0x7c00. Thanks.

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  • Using WeakReference to resolve issue with .NET unregistered event handlers causing memory leaks.

    - by Eric
    The problem: Registered event handlers create a reference from the event to the event handler's instance. If that instance fails to unregister the event handler (via Dispose, presumably), then the instance memory will not be freed by the garbage collector. Example: class Foo { public event Action AnEvent; public void DoEvent() { if (AnEvent != null) AnEvent(); } } class Bar { public Bar(Foo l) { l.AnEvent += l_AnEvent; } void l_AnEvent() { } } If I instantiate a Foo, and pass this to a new Bar constructor, then let go of the Bar object, it will not be freed by the garbage collector because of the AnEvent registration. I consider this a memory leak, and seems just like my old C++ days. I can, of course, make Bar IDisposable, unregister the event in the Dispose() method, and make sure to call Dispose() on instances of it, but why should I have to do this? I first question why events are implemented with strong references? Why not use weak references? An event is used to abstractly notify an object of changes in another object. It seems to me that if the event handler's instance is no longer in use (i.e., there are no non-event references to the object), then any events that it is registered with should automatically be unregistered. What am I missing? I have looked at WeakEventManager. Wow, what a pain. Not only is it very difficult to use, but its documentation is inadequate (see http://msdn.microsoft.com/en-us/library/system.windows.weakeventmanager.aspx -- noticing the "Notes to Inheritors" section that has 6 vaguely described bullets). I have seen other discussions in various places, but nothing I felt I could use. I propose a simpler solution based on WeakReference, as described here. My question is: Does this not meet the requirements with significantly less complexity? To use the solution, the above code is modified as follows: class Foo { public WeakReferenceEvent AnEvent = new WeakReferenceEvent(); internal void DoEvent() { AnEvent.Invoke(); } } class Bar { public Bar(Foo l) { l.AnEvent += l_AnEvent; } void l_AnEvent() { } } Notice two things: 1. The Foo class is modified in two ways: The event is replaced with an instance of WeakReferenceEvent, shown below; and the invocation of the event is changed. 2. The Bar class is UNCHANGED. No need to subclass WeakEventManager, implement IWeakEventListener, etc. OK, so on to the implementation of WeakReferenceEvent. This is shown here. Note that it uses the generic WeakReference that I borrowed from here: http://damieng.com/blog/2006/08/01/implementingweakreferencet I had to add Equals() and GetHashCode() to his class, which I include below for reference. class WeakReferenceEvent { public static WeakReferenceEvent operator +(WeakReferenceEvent wre, Action handler) { wre._delegates.Add(new WeakReference<Action>(handler)); return wre; } public static WeakReferenceEvent operator -(WeakReferenceEvent wre, Action handler) { foreach (var del in wre._delegates) if (del.Target == handler) { wre._delegates.Remove(del); return wre; } return wre; } HashSet<WeakReference<Action>> _delegates = new HashSet<WeakReference<Action>>(); internal void Invoke() { HashSet<WeakReference<Action>> toRemove = null; foreach (var del in _delegates) { if (del.IsAlive) del.Target(); else { if (toRemove == null) toRemove = new HashSet<WeakReference<Action>>(); toRemove.Add(del); } } if (toRemove != null) foreach (var del in toRemove) _delegates.Remove(del); } } public class WeakReference<T> : IDisposable { private GCHandle handle; private bool trackResurrection; public WeakReference(T target) : this(target, false) { } public WeakReference(T target, bool trackResurrection) { this.trackResurrection = trackResurrection; this.Target = target; } ~WeakReference() { Dispose(); } public void Dispose() { handle.Free(); GC.SuppressFinalize(this); } public virtual bool IsAlive { get { return (handle.Target != null); } } public virtual bool TrackResurrection { get { return this.trackResurrection; } } public virtual T Target { get { object o = handle.Target; if ((o == null) || (!(o is T))) return default(T); else return (T)o; } set { handle = GCHandle.Alloc(value, this.trackResurrection ? GCHandleType.WeakTrackResurrection : GCHandleType.Weak); } } public override bool Equals(object obj) { var other = obj as WeakReference<T>; return other != null && Target.Equals(other.Target); } public override int GetHashCode() { return Target.GetHashCode(); } } It's functionality is trivial. I override operator + and - to get the += and -= syntactic sugar matching events. These create WeakReferences to the Action delegate. This allows the garbage collector to free the event target object (Bar in this example) when nobody else is holding on to it. In the Invoke() method, simply run through the weak references and call their Target Action. If any dead (i.e., garbage collected) references are found, remove them from the list. Of course, this only works with delegates of type Action. I tried making this generic, but ran into the missing where T : delegate in C#! As an alternative, simply modify class WeakReferenceEvent to be a WeakReferenceEvent, and replace the Action with Action. Fix the compiler errors and you have a class that can be used like so: class Foo { public WeakReferenceEvent<int> AnEvent = new WeakReferenceEvent<int>(); internal void DoEvent() { AnEvent.Invoke(5); } } Hopefully this will help someone else when they run into the mystery .NET event memory leak!

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  • Java: Handling cookies when logging in with POST

    - by Cris Carter
    I'm having quite some trouble logging in to any site in Java. I'm using the default URLconnection POST request, but I'm unsure how to handle the cookies properly. I tried this guide: http://www.hccp.org/java-net-cookie-how-to.html But couldn't get it working. I've been trying basically for days now, and I really need help if anyone wants to help me. I'll probably be told that it's messy and that I should use a custom library meant for this stuff. I tried downloading one, but wasn't sure how to get it set up and working. I've been trying various things for hours now, and it just won't work. I'd rather do this with a standard URLconnection, but if anyone can help me get another library working that's better for this, that would be great, too. I would really appreciate if someone could post a working source that I could study. What I need is: POST login data to site - Get and store the cookie from the site - use cookie with next URLconnection requests to get logged-in version of the site. Can anyone help me with this? Would be EXTREMELY appreciated. It really does mean a lot. If anyone wants to actually help me out live, please leave an instant-messenger address. Thank you a lot for your time.

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  • SSRS csv export

    - by Lijo
    Hi Team, I am working on SSRS 2005. I have a column that has a comm to be displayed. I write it in the header; but the SP returns without comma for the column header. When I export the report to csv, the column names are taking the name of the text box with is not having comma. Is there a way to display comma in the header when exported to csv? Thanks Lijo

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  • Compilng problems with vector<auto_ptr<> >

    - by petersohn
    Consider the following code: #include <iostream> #include <memory> #include <vector> using namespace std; struct A { int a; A(int a_):a(a_) {} }; int main() { vector<auto_ptr<A> > as; for (int i = 0; i < 10; i++) { auto_ptr<A> a(new A(i)); as.push_back(a); } for (vector<auto_ptr<A> >::iterator it = as.begin(); it != as.end(); ++it) cout << (*it)->a << endl; } When trying to compile it, I get the following obscure compiler error from g++: g++ -O0 -g3 -Wall -c -fmessage-length=0 -MMD -MP -MF"src/proba.d" -MT"src/proba.d" -o"src/proba.o" "../src/proba.cpp" /usr/include/c++/4.1.2/ext/new_allocator.h: In member function ‘void __gnu_cxx::new_allocator<_Tp>::construct(_Tp*, const _Tp&) [with _Tp = std::auto_ptr<A>]’: /usr/include/c++/4.1.2/bits/stl_vector.h:606: instantiated from ‘void std::vector<_Tp, _Alloc>::push_back(const _Tp&) [with _Tp = std::auto_ptr<A>, _Alloc = std::allocator<std::auto_ptr<A> >]’ ../src/proba.cpp:19: instantiated from here /usr/include/c++/4.1.2/ext/new_allocator.h:104: error: passing ‘const std::auto_ptr<A>’ as ‘this’ argument of ‘std::auto_ptr<_Tp>::operator std::auto_ptr_ref<_Tp1>() [with _Tp1 = A, _Tp = A]’ discards qualifiers /usr/include/c++/4.1.2/bits/vector.tcc: In member function ‘void std::vector<_Tp, _Alloc>::_M_insert_aux(__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >, const _Tp&) [with _Tp = std::auto_ptr<A>, _Alloc = std::allocator<std::auto_ptr<A> >]’: /usr/include/c++/4.1.2/bits/stl_vector.h:610: instantiated from ‘void std::vector<_Tp, _Alloc>::push_back(const _Tp&) [with _Tp = std::auto_ptr<A>, _Alloc = std::allocator<std::auto_ptr<A> >]’ ../src/proba.cpp:19: instantiated from here /usr/include/c++/4.1.2/bits/vector.tcc:256: error: passing ‘const std::auto_ptr<A>’ as ‘this’ argument of ‘std::auto_ptr<_Tp>::operator std::auto_ptr_ref<_Tp1>() [with _Tp1 = A, _Tp = A]’ discards qualifiers /usr/include/c++/4.1.2/bits/stl_construct.h: In function ‘void std::_Construct(_T1*, const _T2&) [with _T1 = std::auto_ptr<A>, _T2 = std::auto_ptr<A>]’: /usr/include/c++/4.1.2/bits/stl_uninitialized.h:86: instantiated from ‘_ForwardIterator std::__uninitialized_copy_aux(_InputIterator, _InputIterator, _ForwardIterator, __false_type) [with _InputIterator = __gnu_cxx::__normal_iterator<std::auto_ptr<A>*, std::vector<std::auto_ptr<A>, std::allocator<std::auto_ptr<A> > > >, _ForwardIterator = __gnu_cxx::__normal_iterator<std::auto_ptr<A>*, std::vector<std::auto_ptr<A>, std::allocator<std::auto_ptr<A> > > >]’ /usr/include/c++/4.1.2/bits/stl_uninitialized.h:113: instantiated from ‘_ForwardIterator std::uninitialized_copy(_InputIterator, _InputIterator, _ForwardIterator) [with _InputIterator = __gnu_cxx::__normal_iterator<std::auto_ptr<A>*, std::vector<std::auto_ptr<A>, std::allocator<std::auto_ptr<A> > > >, _ForwardIterator = __gnu_cxx::__normal_iterator<std::auto_ptr<A>*, std::vector<std::auto_ptr<A>, std::allocator<std::auto_ptr<A> > > >]’ /usr/include/c++/4.1.2/bits/stl_uninitialized.h:254: instantiated from ‘_ForwardIterator std::__uninitialized_copy_a(_InputIterator, _InputIterator, _ForwardIterator, std::allocator<_Tp>) [with _InputIterator = __gnu_cxx::__normal_iterator<std::auto_ptr<A>*, std::vector<std::auto_ptr<A>, std::allocator<std::auto_ptr<A> > > >, _ForwardIterator = __gnu_cxx::__normal_iterator<std::auto_ptr<A>*, std::vector<std::auto_ptr<A>, std::allocator<std::auto_ptr<A> > > >, _Tp = std::auto_ptr<A>]’ /usr/include/c++/4.1.2/bits/vector.tcc:279: instantiated from ‘void std::vector<_Tp, _Alloc>::_M_insert_aux(__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >, const _Tp&) [with _Tp = std::auto_ptr<A>, _Alloc = std::allocator<std::auto_ptr<A> >]’ /usr/include/c++/4.1.2/bits/stl_vector.h:610: instantiated from ‘void std::vector<_Tp, _Alloc>::push_back(const _Tp&) [with _Tp = std::auto_ptr<A>, _Alloc = std::allocator<std::auto_ptr<A> >]’ ../src/proba.cpp:19: instantiated from here /usr/include/c++/4.1.2/bits/stl_construct.h:81: error: passing ‘const std::auto_ptr<A>’ as ‘this’ argument of ‘std::auto_ptr<_Tp>::operator std::auto_ptr_ref<_Tp1>() [with _Tp1 = A, _Tp = A]’ discards qualifiers make: *** [src/proba.o] Error 1 It seems to me that there is some kind of problem with consts here. Does this mean that auto_ptr can't be used in vectors?

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  • Best Practices - log in stored procedures?

    - by hgulyan
    If you have a long running SP, do you log somehow it's actions or just wait for this message? "Command(s) completed successfully." I assume, that there can be plenty solutions on this subject, but is there any best practice - a simple solution that is frequently used?

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  • Unable to view USB stick/drive contents

    - by Harshit Sachdeva
    So, I plug-in my USB stick, copy a file from the hard drive to the USB stick, and safely remove the USB stick. I then plug out the USB stick. When I plug the USB stick back into the computer again, the previous contents of the USB stick are all gone. It shows an empty drive. I am using Windows XP SP 2 with an 8 GB USB stick from Transcend.

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  • Making swap faster, easier to use and exception-safe

    - by FredOverflow
    I could not sleep last night and started thinking about std::swap. Here is the familiar C++98 version: template <typename T> void swap(T& a, T& b) { T c(a); a = b; b = c; } If a user-defined class Foo uses external ressources, this is inefficient. The common idiom is to provide a method void Foo::swap(Foo& other) and a specialization of std::swap<Foo>. Note that this does not work with class templates since you cannot partially specialize a function template, and overloading names in the std namespace is illegal. The solution is to write a template function in one's own namespace and rely on argument dependent lookup to find it. This depends critically on the client to follow the "using std::swap idiom" instead of calling std::swap directly. Very brittle. In C++0x, if Foo has a user-defined move constructor and a move assignment operator, providing a custom swap method and a std::swap<Foo> specialization has little to no performance benefit, because the C++0x version of std::swap uses efficient moves instead of copies: #include <utility> template <typename T> void swap(T& a, T& b) { T c(std::move(a)); a = std::move(b); b = std::move(c); } Not having to fiddle with swap anymore already takes a lot of burden away from the programmer. Current compilers do not generate move constructors and move assignment operators automatically yet, but as far as I know, this will change. The only problem left then is exception-safety, because in general, move operations are allowed to throw, and this opens up a whole can of worms. The question "What exactly is the state of a moved-from object?" complicates things further. Then I was thinking, what exactly are the semantics of std::swap in C++0x if everything goes fine? What is the state of the objects before and after the swap? Typically, swapping via move operations does not touch external resources, only the "flat" object representations themselves. So why not simply write a swap template that does exactly that: swap the object representations? #include <cstring> template <typename T> void swap(T& a, T& b) { unsigned char c[sizeof(T)]; memcpy( c, &a, sizeof(T)); memcpy(&a, &b, sizeof(T)); memcpy(&b, c, sizeof(T)); } This is as efficient as it gets: it simply blasts through raw memory. It does not require any intervention from the user: no special swap methods or move operations have to be defined. This means that it even works in C++98 (which does not have rvalue references, mind you). But even more importantly, we can now forget about the exception-safety issues, because memcpy never throws. I can see two potential problems with this approach: First, not all objects are meant to be swapped. If a class designer hides the copy constructor or the copy assignment operator, trying to swap objects of the class should fail at compile-time. We can simply introduce some dead code that checks whether copying and assignment are legal on the type: template <typename T> void swap(T& a, T& b) { if (false) // dead code, never executed { T c(a); // copy-constructible? a = b; // assignable? } unsigned char c[sizeof(T)]; std::memcpy( c, &a, sizeof(T)); std::memcpy(&a, &b, sizeof(T)); std::memcpy(&b, c, sizeof(T)); } Any decent compiler can trivially get rid of the dead code. (There are probably better ways to check the "swap conformance", but that is not the point. What matters is that it's possible). Second, some types might perform "unusual" actions in the copy constructor and copy assignment operator. For example, they might notify observers of their change. I deem this a minor issue, because such kinds of objects probably should not have provided copy operations in the first place. Please let me know what you think of this approach to swapping. Would it work in practice? Would you use it? Can you identify library types where this would break? Do you see additional problems? Discuss!

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  • Use a certain select statement in a stored procedure depending on the Exec statement

    - by MyHeadHurts
    Alright so i am not even sure if this is possible I have a q_00 and q_01 and q_02 which are all in my stored procedure. then on the bottom i have 3 select statements that select a certain catagory for example Sales,Net Sales and INS sales What i want to be able to do is if the user types exec (name of my sp) (sales) (and a year which is the @yearparameter) it will run the sales select statement If they type Exec (name of my SP) netsales (@Yeartoget) it will show the net sales is this possible or do i need multiple stored procedures ALTER PROCEDURE [dbo].[casof] @YearToGet int as ; with q_00 as ( select DIVISION , SDESCR , DYYYY , sum(APRICE) as asofSales , sum(PARTY) as asofPAX , sum(NetAmount) as asofNetSales , sum(InsAmount) as asofInsSales , sum(CancelRevenue) as asofCXSales , sum(OtherAmount) as asofOtherSales , sum(CXVALUE) as asofCXValue from dbo.B101BookingsDetails where Booked <= CONVERT(int,DateAdd(year, @YearToGet - Year(getdate()), DateAdd(day, DateDiff(day, 1, getdate()), 0))) and DYYYY = @YearToGet group by DIVISION, SDESCR, DYYYY ), q_01 as ( select DIVISION , SDESCR , DYYYY , sum(APRICE) as YESales , sum(PARTY) as YEPAX , sum(NetAmount) as YENetSales , sum(InsAmount) as YEInsSales , sum(CancelRevenue) as YECXSales , sum(OtherAmount) as YEOtherSales , sum(CXVALUE) as YECXValue from dbo.B101BookingsDetails where DYYYY=@YearToGet group by DIVISION, SDESCR, DYYYY ), q_02 as ( select DIVISION , SDESCR , DYYYY , sum(APRICE) as CurrentSales , sum(PARTY) as CurrentPAX , sum(NetAmount) as CurrentNetSales , sum(InsAmount) as CurrentInsSales , sum(CancelRevenue) as CurrentCXSales , sum(OtherAmount) as CurrentOtherSales , sum(CXVALUE) as CurrentCXValue from dbo.B101BookingsDetails where Booked <= CONVERT(int,DateAdd(year, (year( getdate() )) - Year(getdate()), DateAdd(day, DateDiff(day, 1, getdate()), 0))) and DYYYY = (year( getdate() )) group by DIVISION, SDESCR, DYYYY ) select a.DIVISION , a.SDESCR , a.DYYYY , asofSales , asofPAX , YESales , YEPAX , CurrentSales , CurrentPAX , asofsales/ ISNULL(NULLIF(yesales,0),1) as percentsales , asofpax/yepax as percentpax ,currentsales/ISNULL(NULLIF((asofsales/ISNULL(NULLIF(yesales,0),1)),0),1) as projectedsales ,currentpax/ISNULL(NULLIF((asofpax/ISNULL(NULLIF(yepax,0),1)),0),1) as projectedpax from q_00 as a join q_01 as b on (b.DIVISION = a.DIVISION and b.SDESCR = a.SDESCR and b.DYYYY = a.DYYYY) join q_02 as c on (b.DIVISION = c.DIVISION and b.SDESCR = c.SDESCR) order by a.DIVISION, a.SDESCR, a.DYYYY ; select a.DIVISION , a.SDESCR , a.DYYYY , asofPAX , asofNetSales , YEPAX , YENetSales , CurrentPAX , CurrentNetSales , asofnetsales/ ISNULL(NULLIF(yenetsales,0),1) as percentnetsales , asofpax/yepax as percentpax ,currentnetsales/ISNULL(NULLIF((asofnetsales/ISNULL(NULLIF(yenetsales,0),1)),0),1) as projectednetsales ,currentpax/ISNULL(NULLIF((asofpax/ISNULL(NULLIF(yepax,0),1)),0),1) as projectedpax from q_00 as a join q_01 as b on (b.DIVISION = a.DIVISION and b.SDESCR = a.SDESCR and b.DYYYY = a.DYYYY) join q_02 as c on (b.DIVISION = c.DIVISION and b.SDESCR = c.SDESCR) order by a.DIVISION, a.SDESCR, a.DYYYY ; select a.DIVISION , a.SDESCR , a.DYYYY , asofPAX , asofInsSales , YEPAX , YEInsSales , CurrentPAX , CurrentInsSales , asofinssales/ ISNULL(NULLIF(yeinssales,0),1) as percentsales , asofpax/yepax as percentpax ,currentinssales/ISNULL(NULLIF((asofinssales/ISNULL(NULLIF(yeinssales,0),1)),0),1) as projectedinssales from q_00 as a join q_01 as b on (b.DIVISION = a.DIVISION and b.SDESCR = a.SDESCR and b.DYYYY = a.DYYYY) join q_02 as c on (b.DIVISION = c.DIVISION and b.SDESCR = c.SDESCR) order by a.DIVISION, a.SDESCR, a.DYYYY ;

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