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  • C# to Java Conversion: What is a [DefaultProperty("value")]?

    - by Shiftbit
    I do not understand how the DefaultProperty Metadata tag work or what it signifies. I've read the MSDN and went through the sample but I find it confusing. DefaultPropertyAttribute Class I've read a few blogs and they seem to refer to the indexers. I'm not sure why you would want metadata for your properties? I am coming from a Java background, perhaps a Java analogy would help. [DefaultProperty("Value")] public abstract class FOO<T> : ANY, IBAR<T> { public FOO() { } public FOO(T value) { this.Value = value; } public virtual T Value { get; set; } }

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  • No sound for headphones

    - by Joel Lino
    I was trying some of the solutions published in this forum for the same problem, but just one in particular work for me: add the line of code in the file alsa-base.conf. This just works for a few days, now the problem is back again. Any solution to fix this problem for good? Compaq Presario CQ40 $ lspci | grep -i audio 00:14.2 Audio device: ATI Technologies Inc SBx00 Azalia (Intel HDA) 01:05.1 Audio device: ATI Technologies Inc RS780 Azalia controller

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  • How to get espeak working?

    - by wisemonkey
    I'm trying read it loud feature of acrobat, so need a text synthesizer, I've installed espeak and libgnome-speech libraries (it didn't work for acrobat right out of the box) so when I started espeak-gui through command line it gave me segmentation fault next I tried only espeak and here is output: ALSA lib pcm.c:2212:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.rear ALSA lib pcm.c:2212:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.center_lfe ALSA lib pcm.c:2212:(snd_pcm_open_noupdate) Unknown PCM cards.pcm.side ALSA lib audio/pcm_bluetooth.c:1613:(audioservice_expect) BT_GET_CAPABILITIES failed : Input/output error(5) ALSA lib audio/pcm_bluetooth.c:1613:(audioservice_expect) BT_GET_CAPABILITIES failed : Input/output error(5) ALSA lib audio/pcm_bluetooth.c:1613:(audioservice_expect) BT_GET_CAPABILITIES failed : Input/output error(5) ALSA lib audio/pcm_bluetooth.c:1613:(audioservice_expect) BT_GET_CAPABILITIES failed : Input/output error(5) ALSA lib pcm_dmix.c:957:(snd_pcm_dmix_open) The dmix plugin supports only playback stream Cannot connect to server socket err = No such file or directory Cannot connect to server socket jack server is not running or cannot be started Any ideas? or any alternative solutions for read it loud? Thanks

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  • Proper QUuid usage in Qt ? (7-Zip DLL usage problems (QLibrary, QUuid GUID conversion, interfaces))

    - by whipsnap
    Hi, I'm trying to write a program that would use 7-Zip DLL for reading files from inside archive files (7z, zip etc). Here's where I'm so far: #include QtCore/QCoreApplication #include QLibrary #include QUuid #include iostream using namespace std; #include "7z910/CPP/7zip/Archive/IArchive.h" #include "7z910/CPP/7zip/IStream.h" #include "MyCom.h" // {23170F69-40C1-278A-1000-000110070000} QUuid CLSID_CFormat7z(0x23170F69, 0x40C1, 0x278A, 0x10, 0x00, 0x00, 0x01, 0x10, 0x07, 0x00, 0x00); typedef int (*CreateObjectFunc)( const GUID *clsID, const GUID *interfaceID, void **outObject); void readFileInArchive() { QLibrary myLib("7z.dll"); CreateObjectFunc myFunction = (CreateObjectFunc)myLib.resolve("CreateObject"); if (myFunction == 0) { cout outArchive; myFunction(&CLSID_CFormat7z, &IID_IOutArchive, (void **)&outArchive); } int main(int argc, char *argv[]) { QCoreApplication a(argc, argv); readFileInArchive(); return a.exec(); } Trying to build that in Qt Creator will lead to following error: cannot convert 'QUuid*' to 'const GUID*' in argument passing How should QUuid be correctly used in this context? Also, being a C++ and Qt newbie I haven't yet quite grasped templates or interfaces, so overall I'm having trouble getting through these first steps. If someone could give tips or even example code on how for example an image file could be extracted from ZIP file (to be shown in Qt GUI later on*), I would highly appreciate that. My main goal at the moment is to write a program with GUI for selecting archive files containing image files (PNG, JPG etc) and displaying those files one at a time in the GUI. A Qt based CDisplayEx in short.

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  • Nonstatic conversion functions; Casting different types, e.g. DirectX vector to OpenGL vector

    - by Markus
    I am currently working on a game "engine" that needs to move values between a 3D engine, a physics engine and a scripting language. Since I need to apply vectors from the physics engine to 3D objects very often and want to be able to control both the 3D, as well as the physics objects through the scripting system, I need a mechanism to convert a vector of one type (e.g. vector3d<float>) to a vector of the other type (e.g. btVector3). Unfortunately I can make no assumptions on how the classes/structs are laid out, so a simple reinterpret_cast probably won't do. So the question is: Is there some sort of 'static'/non-member casting method to achieve basically this: vector3d<float> operator vector3d<float>(btVector3 vector) { // convert and return } btVector3 operator btVector3(vector3d<float> vector) { // convert and return } Right now this won't compile since casting operators need to be member methods. (error C2801: 'operator foo' must be a non-static member)

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  • Intermittent sound

    - by ej159
    The sound on my machine (Medion Akoya S5610) works intermittently. If I reboot enough times I do get sound. This happened before I upgraded, when running Oneiric too. I have fiddled around with alsa-base.conf, putting in different values for model in options snd-hda-intel model=but still the issue persists (although I get the impression that I am more like to have sound on the next reboot if I have edited that file although I can't be sure of this). Adding index=0 does not help the situation either. I have been thinking that this problem could be related some how to the order that driver modules are loaded. The snd-hda-intel module is also used for the sound card (ALC888) in my graphics card. Could it be that these are some how competing? If so, how do I add a preference when they are using the same module? This is the result of lspci -nn | grep Audio (when sound was not working): 00:1b.0 Audio device [0403]: Intel Corporation 82801I (ICH9 Family) HD Audio Controller [8086:293e] (rev 03) 01:00.1 Audio device [0403]: Advanced Micro Devices [AMD] nee ATI RV620 HDMI Audio [Radeon HD 3400 Series] [1002:aa28] I've been wrestling with this problem for ages and ages and have spent days looking for answers on forums but to no avail so I would appreciate any help you can give. Many thanks

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  • Document conversion and viewing, what are the cutting edge solutions?

    - by DigitalLawyer
    Goal: building a web application where a user can: Upload a document (doc, docx, pdf, additional office formats a +) View that document in a browser, preferably in html Download the document (in doc, pdf, additional open formats a +) Current solution: Ruby on Rails Application on Rackspace Users can upload doc and pdf files (AWS) Files can be downloaded in the format in which they were uploaded Thumbnail generation ([doc, pdf] - pdf - png) is done through AbiWord. Certain doc files do not convert well. Documents can be viewed in embedded Google docs viewer (https://docs.google.com/viewer). Certain doc files cannot be displayed. Little flexibility. Potential improvements: Document viewing in pdf through pdf.js Viewing in html (+ annotation) through Crocodoc I'd be glad to hear other users' experiences, and will add good recommendations to this list.

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  • why no implicit conversion from pointer to reference to const pointer.

    - by user316606
    I'll illustrate my question with code: #include <iostream> void PrintInt(const unsigned char*& ptr) { int data = 0; ::memcpy(&data, ptr, sizeof(data)); // advance the pointer reference. ptr += sizeof(data); std::cout << std::hex << data << " " << std::endl; } int main(int, char**) { unsigned char buffer[] = { 0x11, 0x11, 0x11, 0x11, 0x22, 0x22, 0x22, 0x22, }; /* const */ unsigned char* ptr = buffer; PrintInt(ptr); // error C2664: ... PrintInt(ptr); // error C2664: ... return 0; } When I run this code (in VS2008) I get this: error C2664: 'PrintInt' : cannot convert parameter 1 from 'unsigned char *' to 'const unsigned char *&'. If I uncomment the "const" comment it works fine. However shouldn't pointer implicitly convert into const pointer and then reference be taken? Am I wrong in expecting this to work? Thanks!

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  • How do you Bind to a ComboBox in a DataTemplate?

    - by discwiz
    I have a listbox that is bound to an observable collection of Audio (custom class). The Audio class has two properties, DisplayText (string) and a property called TarpIds (Observable Collection of Integer). I need to allow the user to change the TarpID in the combo box for each list item displayed and catch the selection change. I created a DataTemplate that styles the DisplayText property from the Audio object and adds a ComboBox to display the available TarpIDs for this audio (These are dynamic and unique to each Audio). The DisplayText works great, but I can not get the TarpIDs to display in the ComboBox. Here is what I have so far and thanks for any help. FYI I set the ItemSource at run time that binds the ListUploadAudio to the Observable Collection of Audio. <Border BorderBrush="Red" Background="WhiteSmoke" CornerRadius="8"> <Border.Resources> <DataTemplate x:Key="UploadLayout" DataType="Audio"> <StackPanel Orientation="Vertical"> <TextBlock Text="{Binding Path=DisplayText}" FontWeight="Bold" Foreground="Blue"> </TextBlock> <ComboBox x:Name="ListBoxTarpIDs" ItemsSource="{Binding Path=TarpIds}"> </ComboBox> </StackPanel> </DataTemplate> </Border.Resources> <ListBox x:Name="ListUploadAudio" BorderBrush="Transparent" Background="Transparent" Width="230" Margin="10" Height="200" IsSynchronizedWithCurrentItem="True" SelectionMode="Multiple" ItemTemplate="{DynamicResource UploadLayout}"> </ListBox> </Border>

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  • New features of C# 4.0

    This article covers New features of C# 4.0. Article has been divided into below sections. Introduction. Dynamic Lookup. Named and Optional Arguments. Features for COM interop. Variance. Relationship with Visual Basic. Resources. Other interested readings… 22 New Features of Visual Studio 2008 for .NET Professionals 50 New Features of SQL Server 2008 IIS 7.0 New features Introduction It is now close to a year since Microsoft Visual C# 3.0 shipped as part of Visual Studio 2008. In the VS Managed Languages team we are hard at work on creating the next version of the language (with the unsurprising working title of C# 4.0), and this document is a first public description of the planned language features as we currently see them. Please be advised that all this is in early stages of production and is subject to change. Part of the reason for sharing our plans in public so early is precisely to get the kind of feedback that will cause us to improve the final product before it rolls out. Simultaneously with the publication of this whitepaper, a first public CTP (community technology preview) of Visual Studio 2010 is going out as a Virtual PC image for everyone to try. Please use it to play and experiment with the features, and let us know of any thoughts you have. We ask for your understanding and patience working with very early bits, where especially new or newly implemented features do not have the quality or stability of a final product. The aim of the CTP is not to give you a productive work environment but to give you the best possible impression of what we are working on for the next release. The CTP contains a number of walkthroughs, some of which highlight the new language features of C# 4.0. Those are excellent for getting a hands-on guided tour through the details of some common scenarios for the features. You may consider this whitepaper a companion document to these walkthroughs, complementing them with a focus on the overall language features and how they work, as opposed to the specifics of the concrete scenarios. C# 4.0 The major theme for C# 4.0 is dynamic programming. Increasingly, objects are “dynamic” in the sense that their structure and behavior is not captured by a static type, or at least not one that the compiler knows about when compiling your program. Some examples include a. objects from dynamic programming languages, such as Python or Ruby b. COM objects accessed through IDispatch c. ordinary .NET types accessed through reflection d. objects with changing structure, such as HTML DOM objects While C# remains a statically typed language, we aim to vastly improve the interaction with such objects. A secondary theme is co-evolution with Visual Basic. Going forward we will aim to maintain the individual character of each language, but at the same time important new features should be introduced in both languages at the same time. They should be differentiated more by style and feel than by feature set. The new features in C# 4.0 fall into four groups: Dynamic lookup Dynamic lookup allows you to write method, operator and indexer calls, property and field accesses, and even object invocations which bypass the C# static type checking and instead gets resolved at runtime. Named and optional parameters Parameters in C# can now be specified as optional by providing a default value for them in a member declaration. When the member is invoked, optional arguments can be omitted. Furthermore, any argument can be passed by parameter name instead of position. COM specific interop features Dynamic lookup as well as named and optional parameters both help making programming against COM less painful than today. On top of that, however, we are adding a number of other small features that further improve the interop experience. Variance It used to be that an IEnumerable<string> wasn’t an IEnumerable<object>. Now it is – C# embraces type safe “co-and contravariance” and common BCL types are updated to take advantage of that. Dynamic Lookup Dynamic lookup allows you a unified approach to invoking things dynamically. With dynamic lookup, when you have an object in your hand you do not need to worry about whether it comes from COM, IronPython, the HTML DOM or reflection; you just apply operations to it and leave it to the runtime to figure out what exactly those operations mean for that particular object. This affords you enormous flexibility, and can greatly simplify your code, but it does come with a significant drawback: Static typing is not maintained for these operations. A dynamic object is assumed at compile time to support any operation, and only at runtime will you get an error if it wasn’t so. Oftentimes this will be no loss, because the object wouldn’t have a static type anyway, in other cases it is a tradeoff between brevity and safety. In order to facilitate this tradeoff, it is a design goal of C# to allow you to opt in or opt out of dynamic behavior on every single call. The dynamic type C# 4.0 introduces a new static type called dynamic. When you have an object of type dynamic you can “do things to it” that are resolved only at runtime: dynamic d = GetDynamicObject(…); d.M(7); The C# compiler allows you to call a method with any name and any arguments on d because it is of type dynamic. At runtime the actual object that d refers to will be examined to determine what it means to “call M with an int” on it. The type dynamic can be thought of as a special version of the type object, which signals that the object can be used dynamically. It is easy to opt in or out of dynamic behavior: any object can be implicitly converted to dynamic, “suspending belief” until runtime. Conversely, there is an “assignment conversion” from dynamic to any other type, which allows implicit conversion in assignment-like constructs: dynamic d = 7; // implicit conversion int i = d; // assignment conversion Dynamic operations Not only method calls, but also field and property accesses, indexer and operator calls and even delegate invocations can be dispatched dynamically: dynamic d = GetDynamicObject(…); d.M(7); // calling methods d.f = d.P; // getting and settings fields and properties d[“one”] = d[“two”]; // getting and setting thorugh indexers int i = d + 3; // calling operators string s = d(5,7); // invoking as a delegate The role of the C# compiler here is simply to package up the necessary information about “what is being done to d”, so that the runtime can pick it up and determine what the exact meaning of it is given an actual object d. Think of it as deferring part of the compiler’s job to runtime. The result of any dynamic operation is itself of type dynamic. Runtime lookup At runtime a dynamic operation is dispatched according to the nature of its target object d: COM objects If d is a COM object, the operation is dispatched dynamically through COM IDispatch. This allows calling to COM types that don’t have a Primary Interop Assembly (PIA), and relying on COM features that don’t have a counterpart in C#, such as indexed properties and default properties. Dynamic objects If d implements the interface IDynamicObject d itself is asked to perform the operation. Thus by implementing IDynamicObject a type can completely redefine the meaning of dynamic operations. This is used intensively by dynamic languages such as IronPython and IronRuby to implement their own dynamic object models. It will also be used by APIs, e.g. by the HTML DOM to allow direct access to the object’s properties using property syntax. Plain objects Otherwise d is a standard .NET object, and the operation will be dispatched using reflection on its type and a C# “runtime binder” which implements C#’s lookup and overload resolution semantics at runtime. This is essentially a part of the C# compiler running as a runtime component to “finish the work” on dynamic operations that was deferred by the static compiler. Example Assume the following code: dynamic d1 = new Foo(); dynamic d2 = new Bar(); string s; d1.M(s, d2, 3, null); Because the receiver of the call to M is dynamic, the C# compiler does not try to resolve the meaning of the call. Instead it stashes away information for the runtime about the call. This information (often referred to as the “payload”) is essentially equivalent to: “Perform an instance method call of M with the following arguments: 1. a string 2. a dynamic 3. a literal int 3 4. a literal object null” At runtime, assume that the actual type Foo of d1 is not a COM type and does not implement IDynamicObject. In this case the C# runtime binder picks up to finish the overload resolution job based on runtime type information, proceeding as follows: 1. Reflection is used to obtain the actual runtime types of the two objects, d1 and d2, that did not have a static type (or rather had the static type dynamic). The result is Foo for d1 and Bar for d2. 2. Method lookup and overload resolution is performed on the type Foo with the call M(string,Bar,3,null) using ordinary C# semantics. 3. If the method is found it is invoked; otherwise a runtime exception is thrown. Overload resolution with dynamic arguments Even if the receiver of a method call is of a static type, overload resolution can still happen at runtime. This can happen if one or more of the arguments have the type dynamic: Foo foo = new Foo(); dynamic d = new Bar(); var result = foo.M(d); The C# runtime binder will choose between the statically known overloads of M on Foo, based on the runtime type of d, namely Bar. The result is again of type dynamic. The Dynamic Language Runtime An important component in the underlying implementation of dynamic lookup is the Dynamic Language Runtime (DLR), which is a new API in .NET 4.0. The DLR provides most of the infrastructure behind not only C# dynamic lookup but also the implementation of several dynamic programming languages on .NET, such as IronPython and IronRuby. Through this common infrastructure a high degree of interoperability is ensured, but just as importantly the DLR provides excellent caching mechanisms which serve to greatly enhance the efficiency of runtime dispatch. To the user of dynamic lookup in C#, the DLR is invisible except for the improved efficiency. However, if you want to implement your own dynamically dispatched objects, the IDynamicObject interface allows you to interoperate with the DLR and plug in your own behavior. This is a rather advanced task, which requires you to understand a good deal more about the inner workings of the DLR. For API writers, however, it can definitely be worth the trouble in order to vastly improve the usability of e.g. a library representing an inherently dynamic domain. Open issues There are a few limitations and things that might work differently than you would expect. · The DLR allows objects to be created from objects that represent classes. However, the current implementation of C# doesn’t have syntax to support this. · Dynamic lookup will not be able to find extension methods. Whether extension methods apply or not depends on the static context of the call (i.e. which using clauses occur), and this context information is not currently kept as part of the payload. · Anonymous functions (i.e. lambda expressions) cannot appear as arguments to a dynamic method call. The compiler cannot bind (i.e. “understand”) an anonymous function without knowing what type it is converted to. One consequence of these limitations is that you cannot easily use LINQ queries over dynamic objects: dynamic collection = …; var result = collection.Select(e => e + 5); If the Select method is an extension method, dynamic lookup will not find it. Even if it is an instance method, the above does not compile, because a lambda expression cannot be passed as an argument to a dynamic operation. There are no plans to address these limitations in C# 4.0. Named and Optional Arguments Named and optional parameters are really two distinct features, but are often useful together. Optional parameters allow you to omit arguments to member invocations, whereas named arguments is a way to provide an argument using the name of the corresponding parameter instead of relying on its position in the parameter list. Some APIs, most notably COM interfaces such as the Office automation APIs, are written specifically with named and optional parameters in mind. Up until now it has been very painful to call into these APIs from C#, with sometimes as many as thirty arguments having to be explicitly passed, most of which have reasonable default values and could be omitted. Even in APIs for .NET however you sometimes find yourself compelled to write many overloads of a method with different combinations of parameters, in order to provide maximum usability to the callers. Optional parameters are a useful alternative for these situations. Optional parameters A parameter is declared optional simply by providing a default value for it: public void M(int x, int y = 5, int z = 7); Here y and z are optional parameters and can be omitted in calls: M(1, 2, 3); // ordinary call of M M(1, 2); // omitting z – equivalent to M(1, 2, 7) M(1); // omitting both y and z – equivalent to M(1, 5, 7) Named and optional arguments C# 4.0 does not permit you to omit arguments between commas as in M(1,,3). This could lead to highly unreadable comma-counting code. Instead any argument can be passed by name. Thus if you want to omit only y from a call of M you can write: M(1, z: 3); // passing z by name or M(x: 1, z: 3); // passing both x and z by name or even M(z: 3, x: 1); // reversing the order of arguments All forms are equivalent, except that arguments are always evaluated in the order they appear, so in the last example the 3 is evaluated before the 1. Optional and named arguments can be used not only with methods but also with indexers and constructors. Overload resolution Named and optional arguments affect overload resolution, but the changes are relatively simple: A signature is applicable if all its parameters are either optional or have exactly one corresponding argument (by name or position) in the call which is convertible to the parameter type. Betterness rules on conversions are only applied for arguments that are explicitly given – omitted optional arguments are ignored for betterness purposes. If two signatures are equally good, one that does not omit optional parameters is preferred. M(string s, int i = 1); M(object o); M(int i, string s = “Hello”); M(int i); M(5); Given these overloads, we can see the working of the rules above. M(string,int) is not applicable because 5 doesn’t convert to string. M(int,string) is applicable because its second parameter is optional, and so, obviously are M(object) and M(int). M(int,string) and M(int) are both better than M(object) because the conversion from 5 to int is better than the conversion from 5 to object. Finally M(int) is better than M(int,string) because no optional arguments are omitted. Thus the method that gets called is M(int). Features for COM interop Dynamic lookup as well as named and optional parameters greatly improve the experience of interoperating with COM APIs such as the Office Automation APIs. In order to remove even more of the speed bumps, a couple of small COM-specific features are also added to C# 4.0. Dynamic import Many COM methods accept and return variant types, which are represented in the PIAs as object. In the vast majority of cases, a programmer calling these methods already knows the static type of a returned object from context, but explicitly has to perform a cast on the returned value to make use of that knowledge. These casts are so common that they constitute a major nuisance. In order to facilitate a smoother experience, you can now choose to import these COM APIs in such a way that variants are instead represented using the type dynamic. In other words, from your point of view, COM signatures now have occurrences of dynamic instead of object in them. This means that you can easily access members directly off a returned object, or you can assign it to a strongly typed local variable without having to cast. To illustrate, you can now say excel.Cells[1, 1].Value = "Hello"; instead of ((Excel.Range)excel.Cells[1, 1]).Value2 = "Hello"; and Excel.Range range = excel.Cells[1, 1]; instead of Excel.Range range = (Excel.Range)excel.Cells[1, 1]; Compiling without PIAs Primary Interop Assemblies are large .NET assemblies generated from COM interfaces to facilitate strongly typed interoperability. They provide great support at design time, where your experience of the interop is as good as if the types where really defined in .NET. However, at runtime these large assemblies can easily bloat your program, and also cause versioning issues because they are distributed independently of your application. The no-PIA feature allows you to continue to use PIAs at design time without having them around at runtime. Instead, the C# compiler will bake the small part of the PIA that a program actually uses directly into its assembly. At runtime the PIA does not have to be loaded. Omitting ref Because of a different programming model, many COM APIs contain a lot of reference parameters. Contrary to refs in C#, these are typically not meant to mutate a passed-in argument for the subsequent benefit of the caller, but are simply another way of passing value parameters. It therefore seems unreasonable that a C# programmer should have to create temporary variables for all such ref parameters and pass these by reference. Instead, specifically for COM methods, the C# compiler will allow you to pass arguments by value to such a method, and will automatically generate temporary variables to hold the passed-in values, subsequently discarding these when the call returns. In this way the caller sees value semantics, and will not experience any side effects, but the called method still gets a reference. Open issues A few COM interface features still are not surfaced in C#. Most notably these include indexed properties and default properties. As mentioned above these will be respected if you access COM dynamically, but statically typed C# code will still not recognize them. There are currently no plans to address these remaining speed bumps in C# 4.0. Variance An aspect of generics that often comes across as surprising is that the following is illegal: IList<string> strings = new List<string>(); IList<object> objects = strings; The second assignment is disallowed because strings does not have the same element type as objects. There is a perfectly good reason for this. If it were allowed you could write: objects[0] = 5; string s = strings[0]; Allowing an int to be inserted into a list of strings and subsequently extracted as a string. This would be a breach of type safety. However, there are certain interfaces where the above cannot occur, notably where there is no way to insert an object into the collection. Such an interface is IEnumerable<T>. If instead you say: IEnumerable<object> objects = strings; There is no way we can put the wrong kind of thing into strings through objects, because objects doesn’t have a method that takes an element in. Variance is about allowing assignments such as this in cases where it is safe. The result is that a lot of situations that were previously surprising now just work. Covariance In .NET 4.0 the IEnumerable<T> interface will be declared in the following way: public interface IEnumerable<out T> : IEnumerable { IEnumerator<T> GetEnumerator(); } public interface IEnumerator<out T> : IEnumerator { bool MoveNext(); T Current { get; } } The “out” in these declarations signifies that the T can only occur in output position in the interface – the compiler will complain otherwise. In return for this restriction, the interface becomes “covariant” in T, which means that an IEnumerable<A> is considered an IEnumerable<B> if A has a reference conversion to B. As a result, any sequence of strings is also e.g. a sequence of objects. This is useful e.g. in many LINQ methods. Using the declarations above: var result = strings.Union(objects); // succeeds with an IEnumerable<object> This would previously have been disallowed, and you would have had to to some cumbersome wrapping to get the two sequences to have the same element type. Contravariance Type parameters can also have an “in” modifier, restricting them to occur only in input positions. An example is IComparer<T>: public interface IComparer<in T> { public int Compare(T left, T right); } The somewhat baffling result is that an IComparer<object> can in fact be considered an IComparer<string>! It makes sense when you think about it: If a comparer can compare any two objects, it can certainly also compare two strings. This property is referred to as contravariance. A generic type can have both in and out modifiers on its type parameters, as is the case with the Func<…> delegate types: public delegate TResult Func<in TArg, out TResult>(TArg arg); Obviously the argument only ever comes in, and the result only ever comes out. Therefore a Func<object,string> can in fact be used as a Func<string,object>. Limitations Variant type parameters can only be declared on interfaces and delegate types, due to a restriction in the CLR. Variance only applies when there is a reference conversion between the type arguments. For instance, an IEnumerable<int> is not an IEnumerable<object> because the conversion from int to object is a boxing conversion, not a reference conversion. Also please note that the CTP does not contain the new versions of the .NET types mentioned above. In order to experiment with variance you have to declare your own variant interfaces and delegate types. COM Example Here is a larger Office automation example that shows many of the new C# features in action. using System; using System.Diagnostics; using System.Linq; using Excel = Microsoft.Office.Interop.Excel; using Word = Microsoft.Office.Interop.Word; class Program { static void Main(string[] args) { var excel = new Excel.Application(); excel.Visible = true; excel.Workbooks.Add(); // optional arguments omitted excel.Cells[1, 1].Value = "Process Name"; // no casts; Value dynamically excel.Cells[1, 2].Value = "Memory Usage"; // accessed var processes = Process.GetProcesses() .OrderByDescending(p =&gt; p.WorkingSet) .Take(10); int i = 2; foreach (var p in processes) { excel.Cells[i, 1].Value = p.ProcessName; // no casts excel.Cells[i, 2].Value = p.WorkingSet; // no casts i++; } Excel.Range range = excel.Cells[1, 1]; // no casts Excel.Chart chart = excel.ActiveWorkbook.Charts. Add(After: excel.ActiveSheet); // named and optional arguments chart.ChartWizard( Source: range.CurrentRegion, Title: "Memory Usage in " + Environment.MachineName); //named+optional chart.ChartStyle = 45; chart.CopyPicture(Excel.XlPictureAppearance.xlScreen, Excel.XlCopyPictureFormat.xlBitmap, Excel.XlPictureAppearance.xlScreen); var word = new Word.Application(); word.Visible = true; word.Documents.Add(); // optional arguments word.Selection.Paste(); } } The code is much more terse and readable than the C# 3.0 counterpart. Note especially how the Value property is accessed dynamically. This is actually an indexed property, i.e. a property that takes an argument; something which C# does not understand. However the argument is optional. Since the access is dynamic, it goes through the runtime COM binder which knows to substitute the default value and call the indexed property. Thus, dynamic COM allows you to avoid accesses to the puzzling Value2 property of Excel ranges. Relationship with Visual Basic A number of the features introduced to C# 4.0 already exist or will be introduced in some form or other in Visual Basic: · Late binding in VB is similar in many ways to dynamic lookup in C#, and can be expected to make more use of the DLR in the future, leading to further parity with C#. · Named and optional arguments have been part of Visual Basic for a long time, and the C# version of the feature is explicitly engineered with maximal VB interoperability in mind. · NoPIA and variance are both being introduced to VB and C# at the same time. VB in turn is adding a number of features that have hitherto been a mainstay of C#. As a result future versions of C# and VB will have much better feature parity, for the benefit of everyone. Resources All available resources concerning C# 4.0 can be accessed through the C# Dev Center. Specifically, this white paper and other resources can be found at the Code Gallery site. Enjoy! span.fullpost {display:none;}

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  • Logitech webcam device only recognised by one software, without drivers

    - by Ben Franchuk
    A couple weeks ago I purchased a Logitech webcam at a garage sale; It did not come with any driver DVDs or anything like that. I plugged it in, turned on my computer, and continued work as usual. I did not at the time (and still have not) gotten any drivers for the device. Recently, though, I started up an audio software named as Cubase, only to find that it was picking up audio reads off of... something. I checked my sound card, and everything else plugged into my computer, but couldn't find where in the world this audio was being picked up from. There were no microphones listed in the device managers, and no "unknown devices" or whatever. Everything seemed as it always was. Running out of ideas, i blew an air-horn directly into the general area of the webcam, located directly in front of me. Sure enough, the audio peaked, indicating that the microphone was definitely in the webcam and that Cubase was somehow picking up this audio, even without drivers. The software lists the device as a "Universal USB Microphone". Adobe Audition, Soundbooth, and other audio applications cannot find the device either. Why is it that this one software (Cubase) can use this device without a driver, while every other piece of software on the computer can't? Not even the operating system can recognize it. Windows 7 Professional x64 bit

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  • Picking a linux compatible motherboard

    - by Chris
    Last time I bought a new computer (I build them myself) I got a motherboard that had really poor linux support for a long time. Specifically the audio. I had to wait months before the kernel supported the on board audio chipset. That is exactly the situation I'm trying to avoid this time around. I have some specific questions about "server motherboards" actually. I looked at a few models of server motherboards by intel, and some random models on newegg. I wasn't able to see much of a difference from regular desktop motherboard other than most had two sockets, and support for much more ram. These boards seem more popular with Linux users. Why? AMD and Intel both have server CPUs as well. Some question, what's the difference? To make this question more concrete, I was looking at this this motherboard. The main questions about it that I can't answer are: Can I get a motherboard without on board raid and audio? I wanted to get a hardware raid controller and a PCI audio card. I thought a server motherboard would be cheaper and not have these "extras", since who wants an audio card on a server? Where can I found out about Linux support for the components on this board? "Intel ICH10R", "Realtek ALC889", "Marvell 88E8056" I'm buying this computer to work as a Linux desktop for a lot of compiling, coding and audio/video work, but I don't want to rule out the possibility of installing windows and playing some games at one point. (even if the last game I got has been sitting in its box unopened for almost a year). Is it a good idea to buy a "server motherboard" and play games on it, or are desktop boards better value for this? The ultimate solution for me would be a motherboard that had GPL divers for onboard LAN, a single CPU socket, lots of PCI express and PCI. USB 3.0, and no fancy hard disk controllers since I'll be getting a separate one.

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  • My Linux desktop sees my HDMI-connected monitor, but my monitor says "No signal"

    - by hrunting
    I have a Gigabyte H55M-UD2H motherboard and an Acer S271HL monitor. When I connect the monitor to the motherboard via VGA, signal works perfectly. When I connect the monitor via HDMI, the system "sees" the connection, but the monitor receives no signal (the monitor shows a blue box which reads "No Signal" and then the monitor goes into power-saving state). Some fun facts about this: if I hook a different monitor to this box via HDMI, the monitor receives the output without issue (same computer/motherboard, same cable, different monitor) if I connect a different computer to the monitor via HDMI, the monitor receives the output without issue (different computer, same cable, same monitor) no signal is received whether in the OS or in the BIOS there are no BIOS options for controlling video output other than for selection of onboard vs. PCI/PCI-E-based video card (the system has no dedicated video card installed) The box is running Linux, so I have the output of xrandr which shows the connection and the monitor modes detected via DDC: ~$ xrandr --prop Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192 VGA1 disconnected (normal left inverted right x axis y axis) HDMI1 disconnected (normal left inverted right x axis y axis) Broadcast RGB: Full supported: Full Limited 16:2 audio: auto supported: force-dvi off auto on DP1 disconnected (normal left inverted right x axis y axis) Broadcast RGB: Full supported: Full Limited 16:2 audio: auto supported: force-dvi off auto on HDMI2 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 598mm x 336mm EDID: 00ffffffffffff000472ca028d128022 1c160103803c2278ca7b45a4554aa227 0b5054bfef80714f8140818081c08100 9500b300d1c0023a801871382d40582c 450056502100001e000000fd00384c1f 5311000a202020202020000000fc0053 323731484c0a202020202020000000ff 004c55573044303130383531300a01e5 020324f14f0102030405060790111213 1415161f230907078301000067030c00 1000382d023a801871382d40582c4500 56502100001f011d8018711c1620582c 250056502100009f011d007251d01e20 6e28550056502100001e8c0ad08a20e0 2d10103e960056502100001800000000 000000000000000000000000000000de Broadcast RGB: Full supported: Full Limited 16:2 audio: auto supported: force-dvi off auto on 1920x1080 60.0*+ 50.0 25.0 30.0 1680x1050 59.9 1680x945 60.0 1400x1050 74.9 59.9 1600x900 60.0 1280x1024 75.0 60.0 1440x900 75.0 59.9 1280x960 60.0 1366x768 60.0 1360x768 60.0 1280x800 74.9 59.9 1152x864 75.0 1280x768 74.9 60.0 1280x720 50.0 60.0 1440x576 25.0 1024x768 75.1 70.1 60.0 1440x480 30.0 1024x576 60.0 832x624 74.6 800x600 72.2 75.0 60.3 56.2 720x576 50.0 848x480 60.0 720x480 59.9 640x480 72.8 75.0 66.7 60.0 59.9 720x400 70.1 HDMI3 disconnected (normal left inverted right x axis y axis) Broadcast RGB: Full supported: Full Limited 16:2 audio: auto supported: force-dvi off auto on DP2 disconnected (normal left inverted right x axis y axis) Broadcast RGB: Full supported: Full Limited 16:2 audio: auto supported: force-dvi off auto on DP3 disconnected (normal left inverted right x axis y axis) Broadcast RGB: Full supported: Full Limited 16:2 audio: auto supported: force-dvi off auto on How do I get this monitor to recognize the output from this HDMI socket?

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  • picking a linux compatable motherboard

    - by Chris
    Last time I bought a new computer (I build them myself) I got a motherboard that had really poor linux support for a long time. Specifically the audio. I had to wait months before the kernel supported the on board audio chipset. That is exactly the situation I'm trying to avoid this time around. I have some specific questions about "server motherboards" actually. I looked at a few models of server motherboards by intel, and some random models on newegg. I wasn't able to see much of a difference from regular desktop motherboard other than most had two sockets, and support for much more ram. These boards seem more popular with Linux users. Why? AMD and Intel both have server CPUs as well. Some question, what's the difference? To make this question more concrete, I was looking at this this motherboard. The main questions about it that I can't answer are: Can I get a motherboard without on board raid and audio? I wanted to get a hardware raid controller and a PCI audio card. I thought a server motherboard would be cheaper and not have these "extras", since who wants an audio card on a server? Where can I found out about Linux support for the components on this board? "Intel ICH10R", "Realtek ALC889", "Marvell 88E8056" I'm buying this computer to work as a Linux desktop for a lot of compiling, coding and audio/video work, but I don't want to rule out the possibility of installing windows and playing some games at one point. (even if the last game I got has been sitting in its box unopened for almost a year). Is it a good idea to buy a "server motherboard" and play games on it, or are desktop boards better value for this? The ultimate solution for me would be a motherboard that had GPL divers for onboard LAN, a single CPU socket, lots of PCI express and PCI. USB 3.0, and no fancy hard disk controllers since I'll be getting a separate one.

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  • Hard crash when using bluetooth headset on MacBook Pro and Lion 10.7.2

    - by jtalarico
    I recently picked up a bluetooth headset (Motorola S10-HD) and started using it with my MacBook Pro (17" purchased new in 2010) running Lion 10.7.2. Here's what works - stereo audio: iTunes Spotify Pandora (via browser) games (e.g. Minecraft, which is a Java app) audio from YouTube Plex, VLC, other video players Here's what doesn't work well - stereo audio fails and the headset seems to go into mono (i.e. tinny-as-hell) mode: Google Hangout Skype GoTo Meeting Here's what's just downright catastrophic. If I'm listening to stereo audio and then decide to jump into a Skype call (Google Hangout, or GoTo Meeting), bluetooth often crashes and I can only get things working again by shutting down the device, disabling bluetooth, and getting things back up and running again. But the audio is still horrible, and MUCH better using just a simple set of iPhone earbuds and mic. About 80% of the time during such a call, bluetooth crashes. And about 90% of the time, after the call ends, Skype is shut down, or I try to switch back to playing stereo audio, I get a hard crash!! The gray screen of death descends and I'm told I need to restart my machine. In one such instance, even after a reboot, I could not enable bluetooth again ("Turn Bluetooth On" was grayed out in taskbar). Is this just a weak implementation of bluetooth by Apple, or is this a hardware issue? I've seen others posting similar issues even on the Apple support site indicating that bluetooth headsets are failing left and right, but I haven't seen anyone mention hard crashes.

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  • Perform Unit Conversions with the Windows 7 Calculator

    - by Matthew Guay
    Want to easily convert area, volume, temperature, and many other units?  With the Calculator in Windows 7, it’s easy to convert most any unit into another. The New Calculator in Windows 7 Calculator received a visual overhaul in Windows 7, but at first glance it doesn’t seem to have any new functionality.  Here’s Windows 7’s Calculator on the left, with Vista’s calculator on the right.   But, looks can be deceiving.  Window’s 7’s calculator has lots of new exciting features.  Let’s try them out.  Simply type Calculator in the start menu search. To uncover the new features, click the View menu.  Here you can select many different modes, including Unit Conversion mode which we will look at. When you select the Unit Conversion mode, the Calculator will expand with a form on the left side. This conversions pane has 3 drop-down menus.  From the top one, select the type of unit you want to convert. In the next two menus, select which values you wish to convert to and from.  For instance, here we selected Temperature in the first menu, Degrees Fahrenheit in the second menu, and Degrees Celsius in the third menu. Enter the value you wish to convert in the From box, and the conversion will automatically appear in the bottom box. The Calculator contains dozens of conversion values, including more uncommon ones.  So if you’ve ever wanted to know how many US gallons are in a UK gallon, or how many knots a supersonic jet travels in an hour, this is a great tool for you!   Conclusion Windows 7 is filled with little changes that give you an all-around better experience in Windows to help you work more efficiently and productively.  With the new features in the Calculator, you just might feel a little smarter, too! Similar Articles Productive Geek Tips Add Windows Calculator to the Excel 2007 Quick Launch ToolbarEnjoy Quick & Easy Unit Conversion with Convert for WindowsCalculate with Qalculate on LinuxDisable the Annoying “This device can perform faster” Balloon Message in Windows 7Get stats on your Ruby on Rails code TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Install, Remove and HIDE Fonts in Windows 7 Need Help with Your Home Network? Awesome Lyrics Finder for Winamp & Windows Media Player Download Videos from Hulu Pixels invade Manhattan Convert PDF files to ePub to read on your iPad

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  • Setting font size of Closed Captions on iPhone using ffmpeg or mencoder

    - by forthrin
    Does anyone know how to either: Make ffmpeg set subtitle font size in the output video file Make mencoder produce an iPhone-compatible video file (with subtitles) I finally found out how to get Closed Captions video on iPhone, with mkv and srt files as source material. The secret was using the mov_text subtitle codec in ffmpeg (and turning on Closed Captions in the iPhone settings of course): ffmpeg -y -i in.mkv -i in.srt -map 0:0 -map 0:1 -map 1:0 -vcodec copy -acodec aac -ab 256k -scodec mov_text -strict -2 -metadata title="Title" -metadata:s:s:0 language=eng out.mp4 However, the font size appears very small on the iPhone, and I can't find out how to set it with ffmpeg (the iPhone has no option for this). I found out that mencoder has a -subfont-text-scale option, but I don't have a lot of experience with this program. The following, my best attempt so far, produces an output file which is not playable on the iPhone. sudo port install mplayer +mencoder_extras +osd mencoder in.mkv -sub in.srt -o out.mp4 -ovc copy -oac faac -faacopts br=256:mpeg=4:object=2 -channels 2 -srate 48000 -subfont-text-scale 10 -of lavf -lavfopts format=mp4 PS! As requested, here is the output from mencoder: 192 audio & 400 video codecs success: format: 0 data: 0x0 - 0xb64b9d2f libavformat version 54.6.101 (internal) libavformat file format detected. [matroska,webm @ 0x1015c9a50]Unknown entry 0x80 [lavf] stream 0: video (h264), -vid 0 [lavf] stream 1: audio (ac3), -aid 0, -alang eng VIDEO: [H264] 1280x544 0bpp 49.894 fps 0.0 kbps ( 0.0 kbyte/s) [V] filefmt:44 fourcc:0x34363248 size:1280x544 fps:49.894 ftime:=0.0200 ========================================================================== Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders libavcodec version 54.23.100 (internal) AUDIO: 48000 Hz, 2 ch, s16le, 448.0 kbit/29.17% (ratio: 56000->192000) Selected audio codec: [ffac3] afm: ffmpeg (FFmpeg AC-3) ========================================================================== ** MUXER_LAVF ***************************************************************** REMEMBER: MEncoder's libavformat muxing is presently broken and can generate INCORRECT files in the presence of B-frames. Moreover, due to bugs MPlayer will play these INCORRECT files as if nothing were wrong! ******************************************************************************* OK, exit. videocodec: framecopy (1280x544 0bpp fourcc=34363248) VIDEO CODEC ID: 28 AUDIO CODEC ID: 15002, TAG: 0 Writing header... [mp4 @ 0x1015c9a50]Codec for stream 0 does not use global headers but container format requires global headers [mp4 @ 0x1015c9a50]Codec for stream 1 does not use global headers but container format requires global headers Then the following repeats itself for every frame: Pos: 0.0s 1f ( 2%) 0.00fps Trem: 0min 0mb A-V:0.000 [0:0] [mp4 @ 0x1015c9a50]malformated aac bitstream, use -absf aac_adtstoasc Error while writing frame. I recognize -absf aac_adtstoasc as an ffmpeg option (does mencoder spawn ffmpeg?), but I don't know how to pass this option on (my hunch is this is not even the origin of the problem).

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  • Windows App. Thread Aborting Issue

    - by Patrick
    I'm working on an application that has to make specific decisions based on files that are placed into a folder being watched by a file watcher. Part of this decision making process involves renaming files before moving them off to another folder to be processed. Since I'm working with files of all different sizes I created an object that checks the file in a seperate thread to verify that it is "available" and when it is it fires an event. When I run the rename code from inside this available event it works. public void RenameFile_Test() { string psFilePath = @"C:\File1.xlsx"; tgt_File target = new FileObject(psFilePath); target.FileAvailable += new FileEventHandler(OnFileAvailable); target.FileUnAvailable += new FileEventHandler(OnFileUnavailable); } private void OnFileAvailable(object source, FileEventArgs e) { ((FileObject)source).RenameFile(@"C:\File2.xlsx"); } The problem I'm running into is that when the extensions are different from the source file and the rename to file I am making a call to a conversion factory that returns a factory object based on the type of conversion and then converts the file accordingly before doing the rename. When I run that particular piece of code in unit test it works, the factory object is returned, and the conversion happens correctly. But when I run it within the process I get up to the... moExcelApp = new Application(); part of converting an .xls or .xlsx to a .csv and i get a "Thread was being Aborted" error. Any thoughts? Update: There is a bit more information and a bit of map of how the application works currently. Client Application running FSW On File Created event Creates a FileObject passing in the path of the file. On construction the file is validated: if file exists is true then, Thread toAvailableCheck = new Thread(new ThreadStart(AvailableCheck)); toAvailableCheck.Start(); The AvailableCheck Method repeatedly tries to open a streamreader to the file until the reader is either created or the number of attempts times out. If the reader is opened, it fires the FileAvailable event, if not it fires the FileUnAvailable event, passing back itself in the event. The client application is wired to catch those events from inside the Oncreated event of the FSW. the OnFileAvailable method then calls the rename functionality which contains the excel interop call. If the file is being renamed (not converted, extensions stay the same) it does a move to change the name from the old file name to the new, and if its a conversion it runs a conversion factory object which returns the correct type of conversion based on the extensions of the source file and the destination file name. If it is a simple rename it works w/o a problem. If its a conversion (which is the XLS to CSV object that is returned as a part of the factory) the very first thing it does is create a new application object. That is where the application bombs. When i test the factory and conversion/rename process outside of the thread and in its own unit test the process works w/o a problem. Update: I tested the Excel Interop inside a thread by doing this: [TestMethod()] public void ExcelInteropTest() { Thread toExcelInteropThreadTest = new Thread(new ThreadStart(Instantiate_App)); toExcelInteropThreadTest.Start(); } private void Instantiate_App() { Application moExcelApp = new Application(); moExcelApp.Quit(); } And on the line where the application is instatntiated I got the 'A first chance exception of type 'System.Threading.ThreadAbortException' error. So I added; toExcelInteropThreadTest.SetApartmentState(ApartmentState.MTA); after the thread instantiation and before the thread start call and still got the same error. I'm getting the notion that I'm going to have to reconsider the design.

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  • SQL SERVER – Microsoft SQL Server Migration Assistant V6.0 Released

    - by Pinal Dave
    Every company makes a different decision about the database when they start, but as they move forward they mature and make the decision which is based on their experience and best interest of the organization. Similarly, quite a many organizations make different decisions on database, like Sybase, MySQL, Oracle or Access and as time passes by they learn that now they want to move to a different platform. Microsoft makes it easy for SQL Server professional by releasing various Migration Assistant tools. Last week, Microsoft released Microsoft SQL Server Migration Assistant v6.0. Here are different tools released earlier last week to migrate various product to SQL Server. Microsoft SQL Server Migration Assistant v6.0 for Sybase SQL Server Migration Assistant (SSMA) is a free supported tool from Microsoft that simplifies database migration process from Sybase Adaptive Server Enterprise (ASE) to SQL Server and Azure SQL DB. SSMA automates all aspects of migration including migration assessment analysis, schema and SQL statement conversion, data migration as well as migration testing. Microsoft SQL Server Migration Assistant v6.0 for MySQL SQL Server Migration Assistant (SSMA) is a free supported tool from Microsoft that simplifies database migration process from MySQL to SQL Server and Azure SQL DB. SSMA automates all aspects of migration including migration assessment analysis, schema and SQL statement conversion, data migration as well as migration testing. Microsoft SQL Server Migration Assistant v6.0 for Oracle SQL Server Migration Assistant (SSMA) is a free supported tool from Microsoft that simplifies database migration process from Oracle to SQL Server and Azure SQL DB. SSMA automates all aspects of migration including migration assessment analysis, schema and SQL statement conversion, data migration as well as migration testing. Microsoft SQL Server Migration Assistant v6.0 for Access SQL Server Migration Assistant (SSMA) is a free supported tool from Microsoft that simplifies database migration process from Access to SQL Server. SSMA for Access automates conversion of Microsoft Access database objects to SQL Server database objects, loads the objects into SQL Server and Azure SQL DB, and then migrates data from Microsoft Access to SQL Server and Azure SQL DB. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Download, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: SQL Migration

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  • Execution plan warnings–All that glitters is not gold

    - by Dave Ballantyne
    In a previous post, I showed you the new execution plan warnings related to implicit and explicit warnings.  Pretty much as soon as i hit ’post’,  I noticed something rather odd happening. This statement : select top(10) SalesOrderHeader.SalesOrderID, SalesOrderNumberfrom Sales.SalesOrderHeaderjoin Sales.SalesOrderDetail on SalesOrderHeader.SalesOrderID = SalesOrderDetail.SalesOrderID   Throws the “Type conversion may affect cardinality estimation” warning.     Ive done no such conversion in my statement why would that be ?  Well, SalesOrderNumber is a computed column , “(isnull(N'SO'+CONVERT([nvarchar](23),[SalesOrderID],0),N'*** ERROR ***'))”,  so thats where the conversion is.   Wait!!! Am i saying that every type conversion will throw the warning ?  Thankfully, no.  It only appears for columns that are used in predicates ,even if the predicate / join condition is fine ,  and the column is indexed ( and/or , presumably has statistics).    Hopefully , this wont lead to to many wild goose chases, but is definitely something to bear in mind.  If you want to see this fixed then upvote my connect item here.

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