Search Results

Search found 25093 results on 1004 pages for 'console output'.

Page 127/1004 | < Previous Page | 123 124 125 126 127 128 129 130 131 132 133 134  | Next Page >

• How to display an output of float data with 2 decimal places in Java?

  - by via-point

  Can I do it with system.out.print? Thank you.

  Read the article

• What will be the output of this program? And why?

  - by Mac

  I came across a good example written below: class Test { private: int m_iX; public: Test(void): m_iX(0) { } ~Test(void) { } void Show() { printf("Hello World"); } }; int main() { Test* pTemp = NULL; pTemp->Show(); return 0; } But, what does this code mean and do? Thanks

  Read the article

• Node.js Adventure - Host Node.js on Windows Azure Worker Role

  - by Shaun

  In my previous post I demonstrated about how to develop and deploy a Node.js application on Windows Azure Web Site (a.k.a. WAWS). WAWS is a new feature in Windows Azure platform. Since it’s low-cost, and it provides IIS and IISNode components so that we can host our Node.js application though Git, FTP and WebMatrix without any configuration and component installation. But sometimes we need to use the Windows Azure Cloud Service (a.k.a. WACS) and host our Node.js on worker role. Below are some benefits of using worker role. - WAWS leverages IIS and IISNode to host Node.js application, which runs in x86 WOW mode. It reduces the performance comparing with x64 in some cases. - WACS worker role does not need IIS, hence there’s no restriction of IIS, such as 8000 concurrent requests limitation. - WACS provides more flexibility and controls to the developers. For example, we can RDP to the virtual machines of our worker role instances. - WACS provides the service configuration features which can be changed when the role is running. - WACS provides more scaling capability than WAWS. In WAWS we can have at most 3 reserved instances per web site while in WACS we can have up to 20 instances in a subscription. - Since when using WACS worker role we starts the node by ourselves in a process, we can control the input, output and error stream. We can also control the version of Node.js.   Run Node.js in Worker Role Node.js can be started by just having its execution file. This means in Windows Azure, we can have a worker role with the “node.exe” and the Node.js source files, then start it in Run method of the worker role entry class. Let’s create a new windows azure project in Visual Studio and add a new worker role. Since we need our worker role execute the “node.exe” with our application code we need to add the “node.exe” into our project. Right click on the worker role project and add an existing item. By default the Node.js will be installed in the “Program Files\nodejs” folder so we can navigate there and add the “node.exe”. Then we need to create the entry code of Node.js. In WAWS the entry file must be named “server.js”, which is because it’s hosted by IIS and IISNode and IISNode only accept “server.js”. But here as we control everything we can choose any files as the entry code. For example, I created a new JavaScript file named “index.js” in project root. Since we created a C# Windows Azure project we cannot create a JavaScript file from the context menu “Add new item”. We have to create a text file, and then rename it to JavaScript extension. After we added these two files we should set their “Copy to Output Directory” property to “Copy Always”, or “Copy if Newer”. Otherwise they will not be involved in the package when deployed. Let’s paste a very simple Node.js code in the “index.js” as below. As you can see I created a web server listening at port 12345. 1: var http = require("http"); 2: var port = 12345; 3:  4: http.createServer(function (req, res) { 5: res.writeHead(200, { "Content-Type": "text/plain" }); 6: res.end("Hello World\n"); 7: }).listen(port); 8:  9: console.log("Server running at port %d", port); Then we need to start “node.exe” with this file when our worker role was started. This can be done in its Run method. I found the Node.js and entry JavaScript file name, and then create a new process to run it. Our worker role will wait for the process to be exited. If everything is OK once our web server was opened the process will be there listening for incoming requests, and should not be terminated. The code in worker role would be like this. 1: public override void Run() 2: { 3: // This is a sample worker implementation. Replace with your logic. 4: Trace.WriteLine("NodejsHost entry point called", "Information"); 5:  6: // retrieve the node.exe and entry node.js source code file name. 7: var node = Environment.ExpandEnvironmentVariables(@"%RoleRoot%\approot\node.exe"); 8: var js = "index.js"; 9:  10: // prepare the process starting of node.exe 11: var info = new ProcessStartInfo(node, js) 12: { 13: CreateNoWindow = false, 14: ErrorDialog = true, 15: WindowStyle = ProcessWindowStyle.Normal, 16: UseShellExecute = false, 17: WorkingDirectory = Environment.ExpandEnvironmentVariables(@"%RoleRoot%\approot") 18: }; 19: Trace.WriteLine(string.Format("{0} {1}", node, js), "Information"); 20:  21: // start the node.exe with entry code and wait for exit 22: var process = Process.Start(info); 23: process.WaitForExit(); 24: } Then we can run it locally. In the computer emulator UI the worker role started and it executed the Node.js, then Node.js windows appeared. Open the browser to verify the website hosted by our worker role. Next let’s deploy it to azure. But we need some additional steps. First, we need to create an input endpoint. By default there’s no endpoint defined in a worker role. So we will open the role property window in Visual Studio, create a new input TCP endpoint to the port we want our website to use. In this case I will use 80. Even though we created a web server we should add a TCP endpoint of the worker role, since Node.js always listen on TCP instead of HTTP. And then changed the “index.js”, let our web server listen on 80. 1: var http = require("http"); 2: var port = 80; 3:  4: http.createServer(function (req, res) { 5: res.writeHead(200, { "Content-Type": "text/plain" }); 6: res.end("Hello World\n"); 7: }).listen(port); 8:  9: console.log("Server running at port %d", port); Then publish it to Windows Azure. And then in browser we can see our Node.js website was running on WACS worker role. We may encounter an error if we tried to run our Node.js website on 80 port at local emulator. This is because the compute emulator registered 80 and map the 80 endpoint to 81. But our Node.js cannot detect this operation. So when it tried to listen on 80 it will failed since 80 have been used.   Use NPM Modules When we are using WAWS to host Node.js, we can simply install modules we need, and then just publish or upload all files to WAWS. But if we are using WACS worker role, we have to do some extra steps to make the modules work. Assuming that we plan to use “express” in our application. Firstly of all we should download and install this module through NPM command. But after the install finished, they are just in the disk but not included in the worker role project. If we deploy the worker role right now the module will not be packaged and uploaded to azure. Hence we need to add them to the project. On solution explorer window click the “Show all files” button, select the “node_modules” folder and in the context menu select “Include In Project”. But that not enough. We also need to make all files in this module to “Copy always” or “Copy if newer”, so that they can be uploaded to azure with the “node.exe” and “index.js”. This is painful step since there might be many files in a module. So I created a small tool which can update a C# project file, make its all items as “Copy always”. The code is very simple. 1: static void Main(string[] args) 2: { 3: if (args.Length < 1) 4: { 5: Console.WriteLine("Usage: copyallalways [project file]"); 6: return; 7: } 8:  9: var proj = args[0]; 10: File.Copy(proj, string.Format("{0}.bak", proj)); 11:  12: var xml = new XmlDocument(); 13: xml.Load(proj); 14: var nsManager = new XmlNamespaceManager(xml.NameTable); 15: nsManager.AddNamespace("pf", "http://schemas.microsoft.com/developer/msbuild/2003"); 16:  17: // add the output setting to copy always 18: var contentNodes = xml.SelectNodes("//pf:Project/pf:ItemGroup/pf:Content", nsManager); 19: UpdateNodes(contentNodes, xml, nsManager); 20: var noneNodes = xml.SelectNodes("//pf:Project/pf:ItemGroup/pf:None", nsManager); 21: UpdateNodes(noneNodes, xml, nsManager); 22: xml.Save(proj); 23:  24: // remove the namespace attributes 25: var content = xml.InnerXml.Replace("<CopyToOutputDirectory xmlns=\"\">", "<CopyToOutputDirectory>"); 26: xml.LoadXml(content); 27: xml.Save(proj); 28: } 29:  30: static void UpdateNodes(XmlNodeList nodes, XmlDocument xml, XmlNamespaceManager nsManager) 31: { 32: foreach (XmlNode node in nodes) 33: { 34: var copyToOutputDirectoryNode = node.SelectSingleNode("pf:CopyToOutputDirectory", nsManager); 35: if (copyToOutputDirectoryNode == null) 36: { 37: var n = xml.CreateNode(XmlNodeType.Element, "CopyToOutputDirectory", null); 38: n.InnerText = "Always"; 39: node.AppendChild(n); 40: } 41: else 42: { 43: if (string.Compare(copyToOutputDirectoryNode.InnerText, "Always", true) != 0) 44: { 45: copyToOutputDirectoryNode.InnerText = "Always"; 46: } 47: } 48: } 49: } Please be careful when use this tool. I created only for demo so do not use it directly in a production environment. Unload the worker role project, execute this tool with the worker role project file name as the command line argument, it will set all items as “Copy always”. Then reload this worker role project. Now let’s change the “index.js” to use express. 1: var express = require("express"); 2: var app = express(); 3:  4: var port = 80; 5:  6: app.configure(function () { 7: }); 8:  9: app.get("/", function (req, res) { 10: res.send("Hello Node.js!"); 11: }); 12:  13: app.get("/User/:id", function (req, res) { 14: var id = req.params.id; 15: res.json({ 16: "id": id, 17: "name": "user " + id, 18: "company": "IGT" 19: }); 20: }); 21:  22: app.listen(port); Finally let’s publish it and have a look in browser.   Use Windows Azure SQL Database We can use Windows Azure SQL Database (a.k.a. WACD) from Node.js as well on worker role hosting. Since we can control the version of Node.js, here we can use x64 version of “node-sqlserver” now. This is better than if we host Node.js on WAWS since it only support x86. Just install the “node-sqlserver” module from NPM, copy the “sqlserver.node” from “Build\Release” folder to “Lib” folder. Include them in worker role project and run my tool to make them to “Copy always”. Finally update the “index.js” to use WASD. 1: var express = require("express"); 2: var sql = require("node-sqlserver"); 3:  4: var connectionString = "Driver={SQL Server Native Client 10.0};Server=tcp:{SERVER NAME}.database.windows.net,1433;Database={DATABASE NAME};Uid={LOGIN}@{SERVER NAME};Pwd={PASSWORD};Encrypt=yes;Connection Timeout=30;"; 5: var port = 80; 6:  7: var app = express(); 8:  9: app.configure(function () { 10: app.use(express.bodyParser()); 11: }); 12:  13: app.get("/", function (req, res) { 14: sql.open(connectionString, function (err, conn) { 15: if (err) { 16: console.log(err); 17: res.send(500, "Cannot open connection."); 18: } 19: else { 20: conn.queryRaw("SELECT * FROM [Resource]", function (err, results) { 21: if (err) { 22: console.log(err); 23: res.send(500, "Cannot retrieve records."); 24: } 25: else { 26: res.json(results); 27: } 28: }); 29: } 30: }); 31: }); 32:  33: app.get("/text/:key/:culture", function (req, res) { 34: sql.open(connectionString, function (err, conn) { 35: if (err) { 36: console.log(err); 37: res.send(500, "Cannot open connection."); 38: } 39: else { 40: var key = req.params.key; 41: var culture = req.params.culture; 42: var command = "SELECT * FROM [Resource] WHERE [Key] = '" + key + "' AND [Culture] = '" + culture + "'"; 43: conn.queryRaw(command, function (err, results) { 44: if (err) { 45: console.log(err); 46: res.send(500, "Cannot retrieve records."); 47: } 48: else { 49: res.json(results); 50: } 51: }); 52: } 53: }); 54: }); 55:  56: app.get("/sproc/:key/:culture", function (req, res) { 57: sql.open(connectionString, function (err, conn) { 58: if (err) { 59: console.log(err); 60: res.send(500, "Cannot open connection."); 61: } 62: else { 63: var key = req.params.key; 64: var culture = req.params.culture; 65: var command = "EXEC GetItem '" + key + "', '" + culture + "'"; 66: conn.queryRaw(command, function (err, results) { 67: if (err) { 68: console.log(err); 69: res.send(500, "Cannot retrieve records."); 70: } 71: else { 72: res.json(results); 73: } 74: }); 75: } 76: }); 77: }); 78:  79: app.post("/new", function (req, res) { 80: var key = req.body.key; 81: var culture = req.body.culture; 82: var val = req.body.val; 83:  84: sql.open(connectionString, function (err, conn) { 85: if (err) { 86: console.log(err); 87: res.send(500, "Cannot open connection."); 88: } 89: else { 90: var command = "INSERT INTO [Resource] VALUES ('" + key + "', '" + culture + "', N'" + val + "')"; 91: conn.queryRaw(command, function (err, results) { 92: if (err) { 93: console.log(err); 94: res.send(500, "Cannot retrieve records."); 95: } 96: else { 97: res.send(200, "Inserted Successful"); 98: } 99: }); 100: } 101: }); 102: }); 103:  104: app.listen(port); Publish to azure and now we can see our Node.js is working with WASD through x64 version “node-sqlserver”.   Summary In this post I demonstrated how to host our Node.js in Windows Azure Cloud Service worker role. By using worker role we can control the version of Node.js, as well as the entry code. And it’s possible to do some pre jobs before the Node.js application started. It also removed the IIS and IISNode limitation. I personally recommended to use worker role as our Node.js hosting. But there are some problem if you use the approach I mentioned here. The first one is, we need to set all JavaScript files and module files as “Copy always” or “Copy if newer” manually. The second one is, in this way we cannot retrieve the cloud service configuration information. For example, we defined the endpoint in worker role property but we also specified the listening port in Node.js hardcoded. It should be changed that our Node.js can retrieve the endpoint. But I can tell you it won’t be working here. In the next post I will describe another way to execute the “node.exe” and Node.js application, so that we can get the cloud service configuration in Node.js. I will also demonstrate how to use Windows Azure Storage from Node.js by using the Windows Azure Node.js SDK.   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

  Read the article

• Announcing ASP.NET MVC 3 (Release Candidate 2)

  - by ScottGu

  Earlier today the ASP.NET team shipped the final release candidate (RC2) for ASP.NET MVC 3.  You can download and install it here. Almost there… Today’s RC2 release is the near-final release of ASP.NET MVC 3, and is a true “release candidate” in that we are hoping to not make any more code changes with it.  We are publishing it today so that people can do final testing with it, let us know if they find any last minute “showstoppers”, and start updating their apps to use it.  We will officially ship the final ASP.NET MVC 3 “RTM” build in January. Works with both VS 2010 and VS 2010 SP1 Beta Today’s ASP.NET MVC 3 RC2 release works with both the shipping version of Visual Studio 2010 / Visual Web Developer 2010 Express, as well as the newly released VS 2010 SP1 Beta.  This means that you do not need to install VS 2010 SP1 (or the SP1 beta) in order to use ASP.NET MVC 3.  It works just fine with the shipping Visual Studio 2010.  I’ll do a blog post next week, though, about some of the nice additional feature goodies that come with VS 2010 SP1 (including IIS Express and SQL CE support within VS) which make the dev experience for both ASP.NET Web Forms and ASP.NET MVC even better. Bugs and Perf Fixes Today’s ASP.NET MVC 3 RC2 build contains many bug fixes and performance optimizations.  Our latest performance tests indicate that ASP.NET MVC 3 is now faster than ASP.NET MVC 2, and that existing ASP.NET MVC applications will experience a slight performance increase when updated to run using ASP.NET MVC 3. Final Tweaks and Fit-N-Finish In addition to bug fixes and performance optimizations, today’s RC2 build contains a number of last-minute feature tweaks and “fit-n-finish” changes for the new ASP.NET MVC 3 features.  The feedback and suggestions we’ve received during the public previews has been invaluable in guiding these final tweaks, and we really appreciate people’s support in sending this feedback our way.  Below is a short-list of some of the feature changes/tweaks made between last month’s ASP.NET MVC 3 RC release and today’s ASP.NET MVC 3 RC2 release: jQuery updates and addition of jQuery UI The default ASP.NET MVC 3 project templates have been updated to include jQuery 1.4.4 and jQuery Validation 1.7.  We are also excited to announce today that we are including jQuery UI within our default ASP.NET project templates going forward.  jQuery UI provides a powerful set of additional UI widgets and capabilities.  It will be added by default to your project’s \scripts folder when you create new ASP.NET MVC 3 projects. Improved View Scaffolding The T4 templates used for scaffolding views with the Add-View dialog now generates views that use Html.EditorFor instead of helpers such as Html.TextBoxFor. This change enables you to optionally annotate models with metadata (using data annotation attributes) to better customize the output of your UI at runtime. The Add View scaffolding also supports improved detection and usage of primary key information on models (including support for naming conventions like ID, ProductID, etc).  For example: the Add View dialog box uses this information to ensure that the primary key value is not scaffold as an editable form field, and that links between views are auto-generated correctly with primary key information. The default Edit and Create templates also now include references to the jQuery scripts needed for client validation.  Scaffold form views now support client-side validation by default (no extra steps required).  Client-side validation with ASP.NET MVC 3 is also done using an unobtrusive javascript approach – making pages fast and clean. [ControllerSessionState] –> [SessionState] ASP.NET MVC 3 adds support for session-less controllers.  With the initial RC you used a [ControllerSessionState] attribute to specify this.  We shortened this in RC2 to just be [SessionState]: Note that in addition to turning off session state, you can also set it to be read-only (which is useful for webfarm scenarios where you are reading but not updating session state on a particular request). [SkipRequestValidation] –> [AllowHtml] ASP.NET MVC includes built-in support to protect against HTML and Cross-Site Script Injection Attacks, and will throw an error by default if someone tries to post HTML content as input.  Developers need to explicitly indicate that this is allowed (and that they’ve hopefully built their app to securely support it) in order to enable it. With ASP.NET MVC 3, we are also now supporting a new attribute that you can apply to properties of models/viewmodels to indicate that HTML input is enabled, which enables much more granular protection in a DRY way.  In last month’s RC release this attribute was named [SkipRequestValidation].  With RC2 we renamed it to [AllowHtml] to make it more intuitive: Setting the above [AllowHtml] attribute on a model/viewmodel will cause ASP.NET MVC 3 to turn off HTML injection protection when model binding just that property. Html.Raw() helper method The new Razor view engine introduced with ASP.NET MVC 3 automatically HTML encodes output by default.  This helps provide an additional level of protection against HTML and Script injection attacks. With RC2 we are adding a Html.Raw() helper method that you can use to explicitly indicate that you do not want to HTML encode your output, and instead want to render the content “as-is”: ViewModel/View –> ViewBag ASP.NET MVC has (since V1) supported a ViewData[] dictionary within Controllers and Views that enables developers to pass information from a Controller to a View in a late-bound way.  This approach can be used instead of, or in combination with, a strongly-typed model class.  The below code demonstrates a common use case – where a strongly typed Product model is passed to the view in addition to two late-bound variables via the ViewData[] dictionary: With ASP.NET MVC 3 we are introducing a new API that takes advantage of the dynamic type support within .NET 4 to set/retrieve these values.  It allows you to use standard “dot” notation to specify any number of additional variables to be passed, and does not require that you create a strongly-typed class to do so.  With earlier previews of ASP.NET MVC 3 we exposed this API using a dynamic property called “ViewModel” on the Controller base class, and with a dynamic property called “View” within view templates.  A lot of people found the fact that there were two different names confusing, and several also said that using the name ViewModel was confusing in this context – since often you create strongly-typed ViewModel classes in ASP.NET MVC, and they do not use this API.  With RC2 we are exposing a dynamic property that has the same name – ViewBag – within both Controllers and Views.  It is a dynamic collection that allows you to pass additional bits of data from your controller to your view template to help generate a response.  Below is an example of how we could use it to pass a time-stamp message as well as a list of all categories to our view template: Below is an example of how our view template (which is strongly-typed to expect a Product class as its model) can use the two extra bits of information we passed in our ViewBag to generate the response.  In particular, notice how we are using the list of categories passed in the dynamic ViewBag collection to generate a dropdownlist of friendly category names to help set the CategoryID property of our Product object.  The above Controller/View combination will then generate an HTML response like below.    Output Caching Improvements ASP.NET MVC 3’s output caching system no longer requires you to specify a VaryByParam property when declaring an [OutputCache] attribute on a Controller action method.  MVC3 now automatically varies the output cached entries when you have explicit parameters on your action method – allowing you to cleanly enable output caching on actions using code like below: In addition to supporting full page output caching, ASP.NET MVC 3 also supports partial-page caching – which allows you to cache a region of output and re-use it across multiple requests or controllers.  The [OutputCache] behavior for partial-page caching was updated with RC2 so that sub-content cached entries are varied based on input parameters as opposed to the URL structure of the top-level request – which makes caching scenarios both easier and more powerful than the behavior in the previous RC. @model declaration does not add whitespace In earlier previews, the strongly-typed @model declaration at the top of a Razor view added a blank line to the rendered HTML output. This has been fixed so that the declaration does not introduce whitespace. Changed "Html.ValidationMessage" Method to Display the First Useful Error Message The behavior of the Html.ValidationMessage() helper was updated to show the first useful error message instead of simply displaying the first error. During model binding, the ModelState dictionary can be populated from multiple sources with error messages about the property, including from the model itself (if it implements IValidatableObject), from validation attributes applied to the property, and from exceptions thrown while the property is being accessed. When the Html.ValidationMessage() method displays a validation message, it now skips model-state entries that include an exception, because these are generally not intended for the end user. Instead, the method looks for the first validation message that is not associated with an exception and displays that message. If no such message is found, it defaults to a generic error message that is associated with the first exception. RemoteAttribute “Fields” -> “AdditionalFields” ASP.NET MVC 3 includes built-in remote validation support with its validation infrastructure.  This means that the client-side validation script library used by ASP.NET MVC 3 can automatically call back to controllers you expose on the server to determine whether an input element is indeed valid as the user is editing the form (allowing you to provide real-time validation updates). You can accomplish this by decorating a model/viewmodel property with a [Remote] attribute that specifies the controller/action that should be invoked to remotely validate it.  With the RC this attribute had a “Fields” property that could be used to specify additional input elements that should be sent from the client to the server to help with the validation logic.  To improve the clarity of what this property does we have renamed it to “AdditionalFields” with today’s RC2 release. ViewResult.Model and ViewResult.ViewBag Properties The ViewResult class now exposes both a “Model” and “ViewBag” property off of it.  This makes it easier to unit test Controllers that return views, and avoids you having to access the Model via the ViewResult.ViewData.Model property. Installation Notes You can download and install the ASP.NET MVC 3 RC2 build here.  It can be installed on top of the previous ASP.NET MVC 3 RC release (it should just replace the bits as part of its setup). The one component that will not be updated by the above setup (if you already have it installed) is the NuGet Package Manager.  If you already have NuGet installed, please go to the Visual Studio Extensions Manager (via the Tools –> Extensions menu option) and click on the “Updates” tab.  You should see NuGet listed there – please click the “Update” button next to it to have VS update the extension to today’s release. If you do not have NuGet installed (and did not install the ASP.NET MVC RC build), then NuGet will be installed as part of your ASP.NET MVC 3 setup, and you do not need to take any additional steps to make it work. Summary We are really close to the final ASP.NET MVC 3 release, and will deliver the final “RTM” build of it next month.  It has been only a little over 7 months since ASP.NET MVC 2 shipped, and I’m pretty amazed by the huge number of new features, improvements, and refinements that the team has been able to add with this release (Razor, Unobtrusive JavaScript, NuGet, Dependency Injection, Output Caching, and a lot, lot more).  I’ll be doing a number of blog posts over the next few weeks talking about many of them in more depth. Hope this helps, Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

  Read the article

• SQL SERVER – A Quick Look at Logging and Ideas around Logging

  - by pinaldave

  This blog post is written in response to the T-SQL Tuesday post on Logging. When someone talks about logging, personally I get lots of ideas about it. I have seen logging as a very generic term. Let me ask you this question first before I continue writing about logging. What is the first thing comes to your mind when you hear word “Logging”? Now ask the same question to the guy standing next to you. I am pretty confident that you will get  a different answer from different people. I decided to do this activity and asked 5 SQL Server person the same question. Question: What is the first thing comes to your mind when you hear the word “Logging”? Strange enough I got a different answer every single time. Let me just list what answer I got from my friends. Let us go over them one by one. Output Clause The very first person replied output clause. Pretty interesting answer to start with. I see what exactly he was thinking. SQL Server 2005 has introduced a new OUTPUT clause. OUTPUT clause has access to inserted and deleted tables (virtual tables) just like triggers. OUTPUT clause can be used to return values to client clause. OUTPUT clause can be used with INSERT, UPDATE, or DELETE to identify the actual rows affected by these statements. Here are some references for Output Clause: OUTPUT Clause Example and Explanation with INSERT, UPDATE, DELETE Reasons for Using Output Clause – Quiz Tips from the SQL Joes 2 Pros Development Series – Output Clause in Simple Examples Error Logs I was expecting someone to mention Error logs when it is about logging. The error log is the most looked place when there is any error either with the application or there is an error with the operating system. I have kept the policy to check my server’s error log every day. The reason is simple – enough time in my career I have figured out that when I am looking at error logs I find something which I was not expecting. There are cases, when I noticed errors in the error log and I fixed them before end user notices it. Other common practices I always tell my DBA friends to do is that when any error happens they should find relevant entries in the error logs and document the same. It is quite possible that they will see the same error in the error log  and able to fix the error based on the knowledge base which they have created. There can be many different kinds of error log files exists in SQL Server as well – 1) SQL Server Error Logs 2) Windows Event Log 3) SQL Server Agent Log 4) SQL Server Profile Log 5) SQL Server Setup Log etc. Here are some references for Error Logs: Recycle Error Log – Create New Log file without Server Restart SQL Error Messages Change Data Capture I got surprised with this answer. I think more than the answer I was surprised by the person who had answered me this one. I always thought he was expert in HTML, JavaScript but I guess, one should never assume about others. Indeed one of the cool logging feature is Change Data Capture. Change Data Capture records INSERTs, UPDATEs, and DELETEs applied to SQL Server tables, and makes a record available of what changed, where, and when, in simple relational ‘change tables’ rather than in an esoteric chopped salad of XML. These change tables contain columns that reflect the column structure of the source table you have chosen to track, along with the metadata needed to understand the changes that have been made. Here are some references for Change Data Capture: Introduction to Change Data Capture (CDC) in SQL Server 2008 Tuning the Performance of Change Data Capture in SQL Server 2008 Download Script of Change Data Capture (CDC) CDC and TRUNCATE – Cannot truncate table because it is published for replication or enabled for Change Data Capture Dynamic Management View (DMV) I like this answer. If asked I would have not come up with DMV right away but in the spirit of the original question, I think DMV does log the data. DMV logs or stores or records the various data and activity on the SQL Server. Dynamic management views return server state information that can be used to monitor the health of a server instance, diagnose problems, and tune performance. One can get plethero of information from DMVs – High Availability Status, Query Executions Details, SQL Server Resources Status etc. Here are some references for Dynamic Management View (DMV): SQL SERVER – Denali – DMV Enhancement – sys.dm_exec_query_stats – New Columns DMV – sys.dm_os_windows_info – Information about Operating System DMV – sys.dm_os_wait_stats Explanation – Wait Type – Day 3 of 28 DMV sys.dm_exec_describe_first_result_set_for_object – Describes the First Result Metadata for the Module Transaction Log Impact Detection Using DMV – dm_tran_database_transactions Log Files I almost flipped with this final answer from my friend. This should be probably the first answer. Yes, indeed log file logs the SQL Server activities. One can write infinite things about log file. SQL Server uses log file with the extension .ldf to manage transactions and maintain database integrity. Log file ensures that valid data is written out to database and system is in a consistent state. Log files are extremely useful in case of the database failures as with the help of full backup file database can be brought in the desired state (point in time recovery is also possible). SQL Server database has three recovery models – 1) Simple, 2) Full and 3) Bulk Logged. Each of the model uses the .ldf file for performing various activities. It is very important to take the backup of the log files (along with full backup) as one never knows when backup of the log file come into the action and save the day! How to Stop Growing Log File Too Big Reduce the Virtual Log Files (VLFs) from LDF file Log File Growing for Model Database – model Database Log File Grew Too Big master Database Log File Grew Too Big SHRINKFILE and TRUNCATE Log File in SQL Server 2008 Can I just say I loved this month’s T-SQL Tuesday Question. It really provoked very interesting conversation around me. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Optimization, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

  Read the article

• DHCP reply packets do not make it into KVM instance in OpenStack

  - by Lorin Hochstein

  I'm running a KVM instance inside of OpenStack, and it isn't getting an IP address from the DHCP server. Using tcpdump, I can see the request and reply packets on vnet0 of the compute host: # tcpdump -i vnet0 -n port 67 or port 68 tcpdump: WARNING: vnet0: no IPv4 address assigned tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on vnet0, link-type EN10MB (Ethernet), capture size 65535 bytes 19:44:56.176727 IP 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request from fa:16:3e:46:f6:11, length 300 19:44:56.176785 IP 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request from fa:16:3e:46:f6:11, length 300 19:44:56.177315 IP 10.40.0.1.67 > 10.40.0.3.68: BOOTP/DHCP, Reply, length 319 19:45:02.179834 IP 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request from fa:16:3e:46:f6:11, length 300 19:45:02.179904 IP 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request from fa:16:3e:46:f6:11, length 300 19:45:02.180375 IP 10.40.0.1.67 > 10.40.0.3.68: BOOTP/DHCP, Reply, length 319 However, if I do the same thing on eth0 inside the KVM instance, I only see the request packets, not the reply packets. What would prevent the packets from making it from vnet0 of the host to eth0 of the guest? My host is running Ubuntu 12.04 and my guest is running CentOS 6.3. Note that I have added this rule in my iptables, but it doesn't resolve the issue: -A POSTROUTING -p udp -m udp --dport 68 -j CHECKSUM --checksum-fill The instance corresponds to vnet0 and is connected via br100: # brctl show bridge name bridge id STP enabled interfaces br100 8000.54781a8605f2 no eth1 vnet0 vnet1 virbr0 8000.000000000000 yes Here's the full iptables-save: # Generated by iptables-save v1.4.12 on Tue Apr 2 19:47:27 2013 *nat :PREROUTING ACCEPT [8323:2553683] :INPUT ACCEPT [7993:2494942] :OUTPUT ACCEPT [6158:461050] :POSTROUTING ACCEPT [6455:511595] :nova-compute-OUTPUT - [0:0] :nova-compute-POSTROUTING - [0:0] :nova-compute-PREROUTING - [0:0] :nova-compute-float-snat - [0:0] :nova-compute-snat - [0:0] :nova-postrouting-bottom - [0:0] -A PREROUTING -j nova-compute-PREROUTING -A OUTPUT -j nova-compute-OUTPUT -A POSTROUTING -j nova-compute-POSTROUTING -A POSTROUTING -j nova-postrouting-bottom -A POSTROUTING -s 192.168.122.0/24 ! -d 192.168.122.0/24 -p tcp -j MASQUERADE --to-ports 1024-65535 -A POSTROUTING -s 192.168.122.0/24 ! -d 192.168.122.0/24 -p udp -j MASQUERADE --to-ports 1024-65535 -A POSTROUTING -s 192.168.122.0/24 ! -d 192.168.122.0/24 -j MASQUERADE -A nova-compute-snat -j nova-compute-float-snat -A nova-postrouting-bottom -j nova-compute-snat COMMIT # Completed on Tue Apr 2 19:47:27 2013 # Generated by iptables-save v1.4.12 on Tue Apr 2 19:47:27 2013 *mangle :PREROUTING ACCEPT [7969:5385812] :INPUT ACCEPT [7905:5363718] :FORWARD ACCEPT [158:48190] :OUTPUT ACCEPT [6877:8647975] :POSTROUTING ACCEPT [7035:8696165] -A POSTROUTING -o virbr0 -p udp -m udp --dport 68 -j CHECKSUM --checksum-fill -A POSTROUTING -p udp -m udp --dport 68 -j CHECKSUM --checksum-fill COMMIT # Completed on Tue Apr 2 19:47:27 2013 # Generated by iptables-save v1.4.12 on Tue Apr 2 19:47:27 2013 *filter :INPUT ACCEPT [2196774:15856921923] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [2447201:1170227646] :nova-compute-FORWARD - [0:0] :nova-compute-INPUT - [0:0] :nova-compute-OUTPUT - [0:0] :nova-compute-inst-19 - [0:0] :nova-compute-inst-20 - [0:0] :nova-compute-local - [0:0] :nova-compute-provider - [0:0] :nova-compute-sg-fallback - [0:0] :nova-filter-top - [0:0] -A INPUT -j nova-compute-INPUT -A INPUT -i virbr0 -p udp -m udp --dport 53 -j ACCEPT -A INPUT -i virbr0 -p tcp -m tcp --dport 53 -j ACCEPT -A INPUT -i virbr0 -p udp -m udp --dport 67 -j ACCEPT -A INPUT -i virbr0 -p tcp -m tcp --dport 67 -j ACCEPT -A FORWARD -j nova-filter-top -A FORWARD -j nova-compute-FORWARD -A FORWARD -d 192.168.122.0/24 -o virbr0 -m state --state RELATED,ESTABLISHED -j ACCEPT -A FORWARD -s 192.168.122.0/24 -i virbr0 -j ACCEPT -A FORWARD -i virbr0 -o virbr0 -j ACCEPT -A FORWARD -o virbr0 -j REJECT --reject-with icmp-port-unreachable -A FORWARD -i virbr0 -j REJECT --reject-with icmp-port-unreachable -A OUTPUT -j nova-filter-top -A OUTPUT -j nova-compute-OUTPUT -A nova-compute-FORWARD -i br100 -j ACCEPT -A nova-compute-FORWARD -o br100 -j ACCEPT -A nova-compute-inst-19 -m state --state INVALID -j DROP -A nova-compute-inst-19 -m state --state RELATED,ESTABLISHED -j ACCEPT -A nova-compute-inst-19 -j nova-compute-provider -A nova-compute-inst-19 -s 10.40.0.1/32 -p udp -m udp --sport 67 --dport 68 -j ACCEPT -A nova-compute-inst-19 -s 10.40.0.0/16 -j ACCEPT -A nova-compute-inst-19 -p tcp -m tcp --dport 22 -j ACCEPT -A nova-compute-inst-19 -p icmp -j ACCEPT -A nova-compute-inst-19 -j nova-compute-sg-fallback -A nova-compute-inst-20 -m state --state INVALID -j DROP -A nova-compute-inst-20 -m state --state RELATED,ESTABLISHED -j ACCEPT -A nova-compute-inst-20 -j nova-compute-provider -A nova-compute-inst-20 -s 10.40.0.1/32 -p udp -m udp --sport 67 --dport 68 -j ACCEPT -A nova-compute-inst-20 -s 10.40.0.0/16 -j ACCEPT -A nova-compute-inst-20 -p tcp -m tcp --dport 22 -j ACCEPT -A nova-compute-inst-20 -p icmp -j ACCEPT -A nova-compute-inst-20 -j nova-compute-sg-fallback -A nova-compute-local -d 10.40.0.3/32 -j nova-compute-inst-19 -A nova-compute-local -d 10.40.0.4/32 -j nova-compute-inst-20 -A nova-compute-sg-fallback -j DROP -A nova-filter-top -j nova-compute-local COMMIT # Completed on Tue Apr 2 19:47:27 2013

  Read the article

• Package management fails in update-manager with gzip problems and compilation errors. U12.04LTS

  - by HarveyP

  Similar to but not the same as Package management system corrupted. Cannot install or remove packages. U12.04LTS (an earlier problem) with package management system. Followed all of L. D. James suggestions in his answer to no avail. This time as well as the gzip error I am also getting compilation errors. The difference may be due to a lack of compilation in my earlier problem so it may be the same error. The packages concerned are enumerated in the output from update-manager below. Also included below that is the output from apt-get -f install apt-get autoremove gives same output. Tried update without SSL updates - 9 to install and got "Unhandled Error in aptdaemon". Output number 3 below. One at a time - output 4 - is for firefox, first in the list of packages. Falls over at libssl1.0.0 despite deselection of it from update ... Tried apt-get install --reinstall dpkg which succeeded, apt-get install --reinstall tar and apt-get install --reinstall gzip both of which failed at libssl1.0.0 as ever. (as suggested by Subv3rsion elsewhere in this forum) Now cannot apt-get update with complete success even after changing server and apt-get clean - output number 5 below ... 1). Output from update-manager The following packages will be upgraded:<> firefox firefox-globalmenu firefox-locale-en libavcodec-extra-53 libavformat53 libavutil-extra-51 libjson0 libpostproc52 libssl1.0.0 libswscale2 openssl 11 to upgrade, 0 to newly install, 0 to remove and 0 not to upgrade.<br> Need to get 0 B/46.5 MB of archives. After this operation, 1,416 kB of additional disk space will be used.<br> Do you want to continue [Y/n]? y debconf: Perl may be unconfigured (Bareword "gensym" not allowed while "strict subs" in use at /usr/lib/perl/5.14/IO/Handle.pm line 67. BEGIN not safe after errors--compilation aborted at /usr/lib/perl/5.14/IO/Handle.pm line 366. Compilation failed in require at /usr/lib/perl/5.14/IO/Seekable.pm line 9. BEGIN failed--compilation aborted at /usr/lib/perl/5.14/IO/Seekable.pm line 9. Compilation failed in require at /usr/lib/perl/5.14/IO/File.pm line 11. BEGIN failed--compilation aborted at /usr/lib/perl/5.14/IO/File.pm line 11. Compilation failed in require at /usr/share/perl/5.14/FileHandle.pm line 9. Compilation failed in require at (eval 1) line 3. BEGIN failed--compilation aborted at (eval 1) line 3. ) -- aborting (Reading database ... 160575 files and directories currently installed.) Preparing to replace libssl1.0.0 1.0.1-4ubuntu5.14 (using .../libssl1.0.0_1.0.1-4ubuntu5.15_i386.deb) ... Unpacking replacement libssl1.0.0 ... dpkg-deb (subprocess): data: internal gzip read error: '<fd:4>: data error' dpkg-deb: error: subprocess <decompress> returned error exit status 2 dpkg: error processing /var/cache/apt/archives/libssl1.0.0_1.0.1-4ubuntu5.15_i386.deb (--unpack):<br> subprocess dpkg-deb --fsys-tarfile returned error exit status 2 No apport report written because MaxReports has already been reached Bareword "gensym" not allowed while "strict subs" in use at /usr/lib/perl/5.14/IO/Handle.pm line 67. BEGIN not safe after errors--compilation aborted at /usr/lib/perl/5.14/IO/Handle.pm line 366. Compilation failed in require at /usr/lib/perl/5.14/IO/Seekable.pm line 9. BEGIN failed--compilation aborted at /usr/lib/perl/5.14/IO/Seekable.pm line 9. Compilation failed in require at /usr/lib/perl/5.14/IO/File.pm line 11. BEGIN failed--compilation aborted at /usr/lib/perl/5.14/IO/File.pm line 11. Compilation failed in require at /usr/share/perl/5.14/FileHandle.pm line 9. Compilation failed in require at /usr/share/perl5/Debconf/Template.pm line 8. BEGIN failed--compilation aborted at /usr/share/perl5/Debconf/Template.pm line 8. Compilation failed in require at /usr/share/perl5/Debconf/Question.pm line 8. BEGIN failed--compilation aborted at /usr/share/perl5/Debconf/Question.pm line 8. Compilation failed in require at /usr/share/perl5/Debconf/Config.pm line 7. BEGIN failed--compilation aborted at /usr/share/perl5/Debconf/Config.pm line 7. Compilation failed in require at /usr/share/perl5/Debconf/Log.pm line 10. Compilation failed in require at /usr/share/perl5/Debconf/Db.pm line 7. BEGIN failed--compilation aborted at /usr/share/perl5/Debconf/Db.pm line 7. Compilation failed in require at /usr/share/debconf/frontend line 6. BEGIN failed--compilation aborted at /usr/share/debconf/frontend line 6. dpkg: error whale cleanang up: subprgcess installed post-installation script returned error exit status 2 Errors were encountered while processing: /var/cache/apt/archives/libssl1.0.0_1.0.1-4ubuntu5.15_i386.deb E: Sub-process /usr/bin/dpkg returned an error code (1) 2). Output from install -f harveyp@harveyp:~$ sudo apt-get -f install [sudo] password for harveyp: Reading package lists... Done Building dependency tree Reading state information... Done 0 to upgrade, 0 to newly install, 0 to remove and 11 not to upgrade. 1 not fully installed or removed.<br> After this operation, 0 B of additional disk space will be used. E: Internal Error, No file name for libssl1.0.0 3). Unhandled error from aptdaemon Traceback (most recent call last): File "/usr/lib/python2.7/dist-packages/aptdaemon/worker.py", line 1045, in _simulate trans.unauthenticated = self.__simulate(trans) File "/usr/lib/python2.7/dist-packages/aptdaemon/worker.py", line 1160, in __simulate unauthenticated = self._get_unauthenticated() File "/usr/lib/python2.7/dist-packages/aptdaemon/worker.py", line 347, in _get_unauthenticated for pkg in self._iterate_packages(): File "/usr/lib/python2.7/dist-packages/aptdaemon/worker.py", line 1356, in _iterate_packages for enum, pkg in enumerate(self._cache): File "/usr/lib/python2.7/dist-packages/apt/cache.py", line 216, in __iter__ yield self[pkgname] File "/usr/lib/python2.7/dist-packages/apt/cache.py", line 201, in __getitem__ pkg = self._weakref[key] = Package(self, self._cache[key]) KeyError: 'librqrcode-rubq-doc 4). output from update of firefox installArchives() failed: Error in function: < Setting up libssl1.0.0 (1.0.1-4ubuntu5.14) ... Bareword "gensym" not allowed while "strict subs" in use at /usr/lib/perl/5.14/IO/Handle.pm line 67. BEGIN not safe after errors--compilation aborted at /usr/lib/perl/5.14/IO/Handle.pm line 366. Compilation failed in require at /usr/lib/perl/5.14/IO/Seekable.pm line 9. BEGIN failed--compilation aborted at /usr/lib/perl/5.14/IO/Seekable.pm line 9. Compilation failed in require at /usr/lib/perl/5.14/IO/File.pm line 11. BEGIN failed--compilation aborted at /usr/lib/perl/5.14/IO/File.pm line 11. Compilation failed in require at /usr/share/perl/5.14/FileHandle.pm line 9. Compilation failed in require at /usr/share/perl5/Debconf/Template.pm line 8. BEGIN failed--compilation aborted at /usr/share/perl5/Debconf/Template.pm line 8. Compilation failed in require at /usr/share/perl5/Debconf/Question.pm line 8. BEGIN failed--compilation aborted at /usr/share/perl5/Debconf/Question.pm line 8. Compilation failed in require at /usr/share/perl5/Debconf/Config.pm line 7. BEGIN failed--compilation aborted at /usr/share/perl5/Debconf/Config.pm line 7. Compilation failed in require at /usr/share/perl5/Debconf/Log.pm line 10. 5. output from apt-get update ...snip ... Hit http://ubuntu-archive.mirrors.free.org precise-security/multiverse Translation-en Hit http://ubuntu-archive.mirrors.free.org precise-security/restricted Translation-en Hit http://ubuntu-archive.mirrors.free.org precise-security/universe Translation-en Fetched 368 kB in 6s (59.5 kB/s) W: Failed to fetch gzip:/var/lib/apt/lists/partial/ubuntu-archive.mirrors.free.org_ubuntu_dists_precise_universe_source_Sources Hash Sum mismatch E: Some index files failed to download. They have been ignored, or old ones used instead.

  Read the article

• Mixing secure & unsecure channels

  - by user305023

  I am unable to use an unsecure channel once a secure channel has already been registered. The code below works only if on the client side, the unsecured channel is registered before. Is it possible to mix secure and unsecure channels without any constraint on the registration order ? using System; using System.Collections; using System.Runtime.Remoting; using System.Runtime.Remoting.Channels; using System.Runtime.Remoting.Channels.Tcp; public class SampleObject : MarshalByRefObject { public DateTime GetTest() { return DateTime.Now; } } public class SampleObject2 : MarshalByRefObject { public DateTime GetTest2() { return DateTime.Now; } } static class ProgramClient { private static TcpClientChannel RegisterChannel(bool secure, string name, int priority) { IDictionary properties = new Hashtable(); properties.Add("secure", secure); properties.Add("name", name); properties.Add("priority", priority); var clientChannel = new TcpClientChannel(properties, null); ChannelServices.RegisterChannel(clientChannel, false); return clientChannel; } private static void Secure() { RegisterChannel(true, "clientSecure", 2); var testSecure = (SampleObject2)Activator.GetObject(typeof(SampleObject2), "tcp://127.0.0.1:8081/Secured.rem"); Console.WriteLine("secure: " + testSecure.GetTest2().ToLongTimeString()); } private static void Unsecure() { RegisterChannel(false, "clientUnsecure", 1); var test = (SampleObject)Activator.GetObject(typeof(SampleObject), "tcp://127.0.0.1:8080/Unsecured.rem"); Console.WriteLine("unsecure: " + test.GetTest().ToLongTimeString()); } internal static void MainClient() { Console.Write("Press Enter to start."); Console.ReadLine(); // Works only in this order Unsecure(); Secure(); Console.WriteLine("Press ENTER to end"); Console.ReadLine(); } } static class ProgramServer { private static TcpServerChannel RegisterChannel(int port, bool secure, string name) { IDictionary properties = new Hashtable(); properties.Add("port", port); properties.Add("secure", secure); properties.Add("name", name); //properties.Add("impersonate", false); var serverChannel = new TcpServerChannel(properties, null); ChannelServices.RegisterChannel(serverChannel, secure); return serverChannel; } private static void StartUnsecure() { RegisterChannel(8080, false, "unsecure"); RemotingConfiguration.RegisterWellKnownServiceType(typeof(SampleObject), "Unsecured.rem", WellKnownObjectMode.Singleton); } private static void StartSecure() { RegisterChannel(8081, true, "secure"); RemotingConfiguration.RegisterWellKnownServiceType(typeof(SampleObject2), "Secured.rem", WellKnownObjectMode.Singleton); } internal static void MainServer() { StartUnsecure(); StartSecure(); Console.WriteLine("Unsecure: 8080\n Secure: 8081"); Console.WriteLine("Press the enter key to exit..."); Console.ReadLine(); } } class Program { static void Main(string[] args) { if (args.Length == 1 && args[0] == "server") ProgramServer.MainServer(); else ProgramClient.MainClient(); } }

  Read the article

• [.NET Remoting] Mixing secure & unsecure channels

  - by user305023

  I am unable to use an unsecure channel once a secure channel has already been registered. The code below works only if on the client side, the unsecured channel is registered before. Is it possible to mix secure and unsecure channels without any contraints on the registration order ? using System; using System.Collections; using System.Runtime.Remoting; using System.Runtime.Remoting.Channels; using System.Runtime.Remoting.Channels.Tcp; public class SampleObject : MarshalByRefObject { public DateTime GetTest() { return DateTime.Now; } } public class SampleObject2 : MarshalByRefObject { public DateTime GetTest2() { return DateTime.Now; } } static class ProgramClient { private static TcpClientChannel RegisterChannel(bool secure, string name, int priority) { IDictionary properties = new Hashtable(); properties.Add("secure", secure); properties.Add("name", name); properties.Add("priority", priority); var clientChannel = new TcpClientChannel(properties, null); ChannelServices.RegisterChannel(clientChannel, false); return clientChannel; } private static void Secure() { RegisterChannel(true, "clientSecure", 2); var testSecure = (SampleObject2)Activator.GetObject(typeof(SampleObject2), "tcp://127.0.0.1:8081/Secured.rem"); Console.WriteLine("secure: " + testSecure.GetTest2().ToLongTimeString()); } private static void Unsecure() { RegisterChannel(false, "clientUnsecure", 1); var test = (SampleObject)Activator.GetObject(typeof(SampleObject), "tcp://127.0.0.1:8080/Unsecured.rem"); Console.WriteLine("unsecure: " + test.GetTest().ToLongTimeString()); } internal static void MainClient() { Console.Write("Press Enter to start."); Console.ReadLine(); // Works only in this order Unsecure(); Secure(); Console.WriteLine("Press ENTER to end"); Console.ReadLine(); } } static class ProgramServer { private static TcpServerChannel RegisterChannel(int port, bool secure, string name) { IDictionary properties = new Hashtable(); properties.Add("port", port); properties.Add("secure", secure); properties.Add("name", name); //properties.Add("impersonate", false); var serverChannel = new TcpServerChannel(properties, null); ChannelServices.RegisterChannel(serverChannel, secure); return serverChannel; } private static void StartUnsecure() { RegisterChannel(8080, false, "unsecure"); RemotingConfiguration.RegisterWellKnownServiceType(typeof(SampleObject), "Unsecured.rem", WellKnownObjectMode.Singleton); } private static void StartSecure() { RegisterChannel(8081, true, "secure"); RemotingConfiguration.RegisterWellKnownServiceType(typeof(SampleObject2), "Secured.rem", WellKnownObjectMode.Singleton); } internal static void MainServer() { StartUnsecure(); StartSecure(); Console.WriteLine("Unsecure: 8080\n Secure: 8081"); Console.WriteLine("Press the enter key to exit..."); Console.ReadLine(); } } class Program { static void Main(string[] args) { if (args.Length == 1 && args[0] == "server") ProgramServer.MainServer(); else ProgramClient.MainClient(); } }

  Read the article

• How to determine if two generic type values are equal?

  - by comecme

  I'm trying to figure out how I can successfully determine if two generic type values are equal to each other. Based on Mark Byers' answer on this question I would think I can just use value.Equals() where value is a generic type. My actual problem is in a LinkedList implementation, but the problem can be shown with this simpler example. class GenericOjbect<T> { public T Value { get; private set; } public GenericOjbect(T value) { Value = value; } public bool Equals(T value) { return (Value.Equals(value)); } } Now I define an instance of GenericObject<StringBuilder> containing new StringBuilder("StackOverflow"). I would expect to get true if I call Equals(new StringBuilder("StackOverflow") on this GenericObject instance, but I get false. A sample program showing this: using System; using System.Text; class Program { static void Main() { var sb1 = new StringBuilder("StackOverflow"); var sb2 = new StringBuilder("StackOverflow"); Console.WriteLine("StringBuilder compare"); Console.WriteLine("1. == " + (sb1 == sb2)); Console.WriteLine("2. Object.Equals " + (Object.Equals(sb1, sb2))); Console.WriteLine("3. this.Equals " + (sb1.Equals(sb2))); var go1 = new GenericOjbect<StringBuilder>(sb1); var go2 = new GenericOjbect<StringBuilder>(sb2); Console.WriteLine("\nGenericObject compare"); Console.WriteLine("1. == " + (go1 == go2)); Console.WriteLine("2. Object.Equals " + (Object.Equals(go1, go2))); Console.WriteLine("3. this.Equals " + (go1.Equals(go2))); Console.WriteLine("4. Value.Equals " + (go1.Value.Equals(go2.Value))); } } For the three methods of comparing two StringBuilder objects, only the StringBuilder.Equals instance method (the third line) returns true. This is what I expected. But when comparing the GenericObject objects, its Equals() method (the third line) returns false. Interestingly enough, the fourth compare method does return true. I'd think the third and fourth comparison are actually doing the same thing. I would have expected true. Because in the Equals() method of the GenericObject class, both value and Value are of type T which in this case is a StringBuilder. Based on Mark Byers' answer in this question, I would've expected the Value.Equals() method to be using the StringBuilder's Equals() method. And as I've shown, the StringBuilder's Equal() method does return true. I've even tried public bool Equals(T value) { return EqualityComparer<T>.Default.Equals(Value, value); } but that also returns false. So, two questions here: Why doesn't the code return true? How could I implement the Equals method so it does return true?

  Read the article

• C#/.NET Little Wonders: Fun With Enum Methods

  - by James Michael Hare

  Once again lets dive into the Little Wonders of .NET, those small things in the .NET languages and BCL classes that make development easier by increasing readability, maintainability, and/or performance. So probably every one of us has used an enumerated type at one time or another in a C# program.  The enumerated types we create are a great way to represent that a value can be one of a set of discrete values (or a combination of those values in the case of bit flags). But the power of enum types go far beyond simple assignment and comparison, there are many methods in the Enum class (that all enum types “inherit” from) that can give you even more power when dealing with them. IsDefined() – check if a given value exists in the enum Are you reading a value for an enum from a data source, but are unsure if it is actually a valid value or not?  Casting won’t tell you this, and Parse() isn’t guaranteed to balk either if you give it an int or a combination of flags.  So what can we do? Let’s assume we have a small enum like this for result codes we want to return back from our business logic layer: 1: public enum ResultCode 2: { 3: Success, 4: Warning, 5: Error 6: } In this enum, Success will be zero (unless given another value explicitly), Warning will be one, and Error will be two. So what happens if we have code like this where perhaps we’re getting the result code from another data source (could be database, could be web service, etc)? 1: public ResultCode PerformAction() 2: { 3: // set up and call some method that returns an int. 4: int result = ResultCodeFromDataSource(); 5:  6: // this will suceed even if result is < 0 or > 2. 7: return (ResultCode) result; 8: } So what happens if result is –1 or 4?  Well, the cast does not fail, so what we end up with would be an instance of a ResultCode that would have a value that’s outside of the bounds of the enum constants we defined. This means if you had a block of code like: 1: switch (result) 2: { 3: case ResultType.Success: 4: // do success stuff 5: break; 6:  7: case ResultType.Warning: 8: // do warning stuff 9: break; 10:  11: case ResultType.Error: 12: // do error stuff 13: break; 14: } That you would hit none of these blocks (which is a good argument for always having a default in a switch by the way). So what can you do?  Well, there is a handy static method called IsDefined() on the Enum class which will tell you if an enum value is defined.  1: public ResultCode PerformAction() 2: { 3: int result = ResultCodeFromDataSource(); 4:  5: if (!Enum.IsDefined(typeof(ResultCode), result)) 6: { 7: throw new InvalidOperationException("Enum out of range."); 8: } 9:  10: return (ResultCode) result; 11: } In fact, this is often recommended after you Parse() or cast a value to an enum as there are ways for values to get past these methods that may not be defined. If you don’t like the syntax of passing in the type of the enum, you could clean it up a bit by creating an extension method instead that would allow you to call IsDefined() off any isntance of the enum: 1: public static class EnumExtensions 2: { 3: // helper method that tells you if an enum value is defined for it's enumeration 4: public static bool IsDefined(this Enum value) 5: { 6: return Enum.IsDefined(value.GetType(), value); 7: } 8: }   HasFlag() – an easier way to see if a bit (or bits) are set Most of us who came from the land of C programming have had to deal extensively with bit flags many times in our lives.  As such, using bit flags may be almost second nature (for a quick refresher on bit flags in enum types see one of my old posts here). However, in higher-level languages like C#, the need to manipulate individual bit flags is somewhat diminished, and the code to check for bit flag enum values may be obvious to an advanced developer but cryptic to a novice developer. For example, let’s say you have an enum for a messaging platform that contains bit flags: 1: // usually, we pluralize flags enum type names 2: [Flags] 3: public enum MessagingOptions 4: { 5: None = 0, 6: Buffered = 0x01, 7: Persistent = 0x02, 8: Durable = 0x04, 9: Broadcast = 0x08 10: } We can combine these bit flags using the bitwise OR operator (the ‘|’ pipe character): 1: // combine bit flags using 2: var myMessenger = new Messenger(MessagingOptions.Buffered | MessagingOptions.Broadcast); Now, if we wanted to check the flags, we’d have to test then using the bit-wise AND operator (the ‘&’ character): 1: if ((options & MessagingOptions.Buffered) == MessagingOptions.Buffered) 2: { 3: // do code to set up buffering... 4: // ... 5: } While the ‘|’ for combining flags is easy enough to read for advanced developers, the ‘&’ test tends to be easy for novice developers to get wrong.  First of all you have to AND the flag combination with the value, and then typically you should test against the flag combination itself (and not just for a non-zero)!  This is because the flag combination you are testing with may combine multiple bits, in which case if only one bit is set, the result will be non-zero but not necessarily all desired bits! Thanks goodness in .NET 4.0 they gave us the HasFlag() method.  This method can be called from an enum instance to test to see if a flag is set, and best of all you can avoid writing the bit wise logic yourself.  Not to mention it will be more readable to a novice developer as well: 1: if (options.HasFlag(MessagingOptions.Buffered)) 2: { 3: // do code to set up buffering... 4: // ... 5: } It is much more concise and unambiguous, thus increasing your maintainability and readability. It would be nice to have a corresponding SetFlag() method, but unfortunately generic types don’t allow you to specialize on Enum, which makes it a bit more difficult.  It can be done but you have to do some conversions to numeric and then back to the enum which makes it less of a payoff than having the HasFlag() method.  But if you want to create it for symmetry, it would look something like this: 1: public static T SetFlag<T>(this Enum value, T flags) 2: { 3: if (!value.GetType().IsEquivalentTo(typeof(T))) 4: { 5: throw new ArgumentException("Enum value and flags types don't match."); 6: } 7:  8: // yes this is ugly, but unfortunately we need to use an intermediate boxing cast 9: return (T)Enum.ToObject(typeof (T), Convert.ToUInt64(value) | Convert.ToUInt64(flags)); 10: } Note that since the enum types are value types, we need to assign the result to something (much like string.Trim()).  Also, you could chain several SetFlag() operations together or create one that takes a variable arg list if desired. Parse() and ToString() – transitioning from string to enum and back Sometimes, you may want to be able to parse an enum from a string or convert it to a string - Enum has methods built in to let you do this.  Now, many may already know this, but may not appreciate how much power are in these two methods. For example, if you want to parse a string as an enum, it’s easy and works just like you’d expect from the numeric types: 1: string optionsString = "Persistent"; 2:  3: // can use Enum.Parse, which throws if finds something it doesn't like... 4: var result = (MessagingOptions)Enum.Parse(typeof (MessagingOptions), optionsString); 5:  6: if (result == MessagingOptions.Persistent) 7: { 8: Console.WriteLine("It worked!"); 9: } Note that Enum.Parse() will throw if it finds a value it doesn’t like.  But the values it likes are fairly flexible!  You can pass in a single value, or a comma separated list of values for flags and it will parse them all and set all bits: 1: // for string values, can have one, or comma separated. 2: string optionsString = "Persistent, Buffered"; 3:  4: var result = (MessagingOptions)Enum.Parse(typeof (MessagingOptions), optionsString); 5:  6: if (result.HasFlag(MessagingOptions.Persistent) && result.HasFlag(MessagingOptions.Buffered)) 7: { 8: Console.WriteLine("It worked!"); 9: } Or you can parse in a string containing a number that represents a single value or combination of values to set: 1: // 3 is the combination of Buffered (0x01) and Persistent (0x02) 2: var optionsString = "3"; 3:  4: var result = (MessagingOptions) Enum.Parse(typeof (MessagingOptions), optionsString); 5:  6: if (result.HasFlag(MessagingOptions.Persistent) && result.HasFlag(MessagingOptions.Buffered)) 7: { 8: Console.WriteLine("It worked again!"); 9: } And, if you really aren’t sure if the parse will work, and don’t want to handle an exception, you can use TryParse() instead: 1: string optionsString = "Persistent, Buffered"; 2: MessagingOptions result; 3:  4: // try parse returns true if successful, and takes an out parm for the result 5: if (Enum.TryParse(optionsString, out result)) 6: { 7: if (result.HasFlag(MessagingOptions.Persistent) && result.HasFlag(MessagingOptions.Buffered)) 8: { 9: Console.WriteLine("It worked!"); 10: } 11: } So we covered parsing a string to an enum, what about reversing that and converting an enum to a string?  The ToString() method is the obvious and most basic choice for most of us, but did you know you can pass a format string for enum types that dictate how they are written as a string?: 1: MessagingOptions value = MessagingOptions.Buffered | MessagingOptions.Persistent; 2:  3: // general format, which is the default, 4: Console.WriteLine("Default : " + value); 5: Console.WriteLine("G (default): " + value.ToString("G")); 6:  7: // Flags format, even if type does not have Flags attribute. 8: Console.WriteLine("F (flags) : " + value.ToString("F")); 9:  10: // integer format, value as number. 11: Console.WriteLine("D (num) : " + value.ToString("D")); 12:  13: // hex format, value as hex 14: Console.WriteLine("X (hex) : " + value.ToString("X")); Which displays: 1: Default : Buffered, Persistent 2: G (default): Buffered, Persistent 3: F (flags) : Buffered, Persistent 4: D (num) : 3 5: X (hex) : 00000003 Now, you may not really see a difference here between G and F because I used a [Flags] enum, the difference is that the “F” option treats the enum as if it were flags even if the [Flags] attribute is not present.  Let’s take a non-flags enum like the ResultCode used earlier: 1: // yes, we can do this even if it is not [Flags] enum. 2: ResultCode value = ResultCode.Warning | ResultCode.Error; And if we run that through the same formats again we get: 1: Default : 3 2: G (default): 3 3: F (flags) : Warning, Error 4: D (num) : 3 5: X (hex) : 00000003 Notice that since we had multiple values combined, but it was not a [Flags] marked enum, the G and default format gave us a number instead of a value name.  This is because the value was not a valid single-value constant of the enum.  However, using the F flags format string, it broke out the value into its component flags even though it wasn’t marked [Flags]. So, if you want to get an enum to display appropriately for whether or not it has the [Flags] attribute, use G which is the default.  If you always want it to attempt to break down the flags, use F.  For numeric output, obviously D or  X are the best choice depending on whether you want decimal or hex. Summary Hopefully, you learned a couple of new tricks with using the Enum class today!  I’ll add more little wonders as I think of them and thanks for all the invaluable input!   Technorati Tags: C#,.NET,Little Wonders,Enum,BlackRabbitCoder

  Read the article

• AutoMapper MappingFunction from Source Type of NameValueCollection

  - by REA_ANDREW

  I have had a situation arise today where I need to construct a complex type from a source of a NameValueCollection.  A little while back I submitted a patch for the Agatha Project to include REST (JSON and XML) support for the service contract.  I realized today that as useful as it is, it did not actually support true REST conformance, as REST should support GET so that you can use JSONP from JavaScript directly meaning you can query cross domain services.  My original implementation for POX and JSON used the POST method and this immediately rules out JSONP as from reading, JSONP only works with GET Requests. This then raised another issue.  The current operation contract of Agatha and one of its main benefits is that you can supply an array of Request objects in a single request, limiting the about of server requests you need to make.  Now, at the present time I am thinking that this will not be the case for the REST imlementation but will yield the benefits of the fact that : The same Request objects can be used for SOAP and RST (POX, JSON) The construct of the JavaScript functions will be simpler and more readable It will enable the use of JSONP for cross domain REST Services The current contract for the Agatha WcfRequestProcessor is at time of writing the following: [ServiceContract] public interface IWcfRequestProcessor { [OperationContract(Name = "ProcessRequests")] [ServiceKnownType("GetKnownTypes", typeof(KnownTypeProvider))] [TransactionFlow(TransactionFlowOption.Allowed)] Response[] Process(params Request[] requests); [OperationContract(Name = "ProcessOneWayRequests", IsOneWay = true)] [ServiceKnownType("GetKnownTypes", typeof(KnownTypeProvider))] void ProcessOneWayRequests(params OneWayRequest[] requests); }   My current proposed solution, and at the very early stages of my concept is as follows: [ServiceContract] public interface IWcfRestJsonRequestProcessor { [OperationContract(Name="process")] [ServiceKnownType("GetKnownTypes", typeof(KnownTypeProvider))] [TransactionFlow(TransactionFlowOption.Allowed)] [WebGet(UriTemplate = "process/{name}/{*parameters}", BodyStyle = WebMessageBodyStyle.WrappedResponse, ResponseFormat = WebMessageFormat.Json)] Response[] Process(string name, NameValueCollection parameters); [OperationContract(Name="processoneway",IsOneWay = true)] [ServiceKnownType("GetKnownTypes", typeof(KnownTypeProvider))] [WebGet(UriTemplate = "process-one-way/{name}/{*parameters}", BodyStyle = WebMessageBodyStyle.WrappedResponse, ResponseFormat = WebMessageFormat.Json)] void ProcessOneWayRequests(string name, NameValueCollection parameters); }   Now this part I have not yet implemented, it is the preliminart step which I have developed which will allow me to take the name of the Request Type and the NameValueCollection and construct the complex type which is that of the Request which I can then supply to a nested instance of the original IWcfRequestProcessor  and work as it should normally.  To give an example of some of the urls which you I envisage with this method are: http://www.url.com/service.svc/json/process/getweather/?location=london http://www.url.com/service.svc/json/process/getproductsbycategory/?categoryid=1 http://www.url.om/service.svc/json/process/sayhello/?name=andy Another reason why my direction has gone to a single request for the REST implementation is because of restrictions which are imposed by browsers on the length of the url.  From what I have read this is on average 2000 characters.  I think that this is a very acceptable usage limit in the context of using 1 request, but I do not think this is acceptable for accommodating multiple requests chained together.  I would love to be corrected on that one, I really would but unfortunately from what I have read I have come to the conclusion that this is not the case. The mapping function So, as I say this is just the first pass I have made at this, and I am not overly happy with the try catch for detecting types without default constructors.  I know there is a better way but for the minute, it escapes me.  I would also like to know the correct way for adding mapping functions and not using the anonymous way that I have used.  To achieve this I have used recursion which I am sure is what other mapping function use. As you do have to go as deep as the complex type is. public static object RecurseType(NameValueCollection collection, Type type, string prefix) { try { var returnObject = Activator.CreateInstance(type); foreach (var property in type.GetProperties()) { foreach (var key in collection.AllKeys) { if (String.IsNullOrEmpty(prefix) || key.Length > prefix.Length) { var propertyNameToMatch = String.IsNullOrEmpty(prefix) ? key : key.Substring(property.Name.IndexOf(prefix) + prefix.Length + 1); if (property.Name == propertyNameToMatch) { property.SetValue(returnObject, Convert.ChangeType(collection.Get(key), property.PropertyType), null); } else if(property.GetValue(returnObject,null) == null) { property.SetValue(returnObject, RecurseType(collection, property.PropertyType, String.Concat(prefix, property.PropertyType.Name)), null); } } } } return returnObject; } catch (MissingMethodException) { //Quite a blunt way of dealing with Types without default constructor return null; } }   Another thing is performance, I have not measured this in anyway, it is as I say the first pass, so I hope this can be the start of a more perfected implementation.  I tested this out with a complex type of three levels, there is no intended logical meaning to the properties, they are simply for the purposes of example.  You could call this a spiking session, as from here on in, now I know what I am building I would take a more TDD approach.  OK, purists, why did I not do this from the start, well I didn’t, this was a brain dump and now I know what I am building I can. The console test and how I used with AutoMapper is as follows: static void Main(string[] args) { var collection = new NameValueCollection(); collection.Add("Name", "Andrew Rea"); collection.Add("Number", "1"); collection.Add("AddressLine1", "123 Street"); collection.Add("AddressNumber", "2"); collection.Add("AddressPostCodeCountry", "United Kingdom"); collection.Add("AddressPostCodeNumber", "3"); AutoMapper.Mapper.CreateMap<NameValueCollection, Person>() .ConvertUsing(x => { return(Person) RecurseType(x, typeof(Person), null); }); var person = AutoMapper.Mapper.Map<NameValueCollection, Person>(collection); Console.WriteLine(person.Name); Console.WriteLine(person.Number); Console.WriteLine(person.Address.Line1); Console.WriteLine(person.Address.Number); Console.WriteLine(person.Address.PostCode.Country); Console.WriteLine(person.Address.PostCode.Number); Console.ReadLine(); }   Notice the convention that I am using and that this method requires you do use.  Each property is prefixed with the constructed name of its parents combined.  This is the convention used by AutoMapper and it makes sense. I can also think of other uses for this including using with ASP.NET MVC ModelBinders for creating a complex type from the QueryString which is itself is a NameValueCollection. Hope this is of some help to people and I would welcome any code reviews you could give me. References: Agatha : http://code.google.com/p/agatha-rrsl/ AutoMapper : http://automapper.codeplex.com/   Cheers for now, Andrew   P.S. I will have the proposed solution for a more complete REST implementation for AGATHA very soon. 

  Read the article

• What's up with LDoms: Part 2 - Creating a first, simple guest

  - by Stefan Hinker

  Welcome back! In the first part, we discussed the basic concepts of LDoms and how to configure a simple control domain.  We saw how resources were put aside for guest systems and what infrastructure we need for them.  With that, we are now ready to create a first, very simple guest domain.  In this first example, we'll keep things very simple.  Later on, we'll have a detailed look at things like sizing, IO redundancy, other types of IO as well as security. For now,let's start with this very simple guest.  It'll have one core's worth of CPU, one crypto unit, 8GB of RAM, a single boot disk and one network port.  CPU and RAM are easy.  The network port we'll create by attaching a virtual network port to the vswitch we created in the primary domain.  This is very much like plugging a cable into a computer system on one end and a network switch on the other.  For the boot disk, we'll need two things: A physical piece of storage to hold the data - this is called the backend device in LDoms speak.  And then a mapping between that storage and the guest domain, giving it access to that virtual disk.  For this example, we'll use a ZFS volume for the backend.  We'll discuss what other options there are for this and how to chose the right one in a later article.  Here we go: root@sun # ldm create mars root@sun # ldm set-vcpu 8 mars root@sun # ldm set-mau 1 mars root@sun # ldm set-memory 8g mars root@sun # zfs create rpool/guests root@sun # zfs create -V 32g rpool/guests/mars.bootdisk root@sun # ldm add-vdsdev /dev/zvol/dsk/rpool/guests/mars.bootdisk \ mars.root@primary-vds root@sun # ldm add-vdisk root mars.root@primary-vds mars root@sun # ldm add-vnet net0 switch-primary mars That's all, mars is now ready to power on.  There are just three commands between us and the OK prompt of mars:  We have to "bind" the domain, start it and connect to its console.  Binding is the process where the hypervisor actually puts all the pieces that we've configured together.  If we made a mistake, binding is where we'll be told (starting in version 2.1, a lot of sanity checking has been put into the config commands themselves, but binding will catch everything else).  Once bound, we can start (and of course later stop) the domain, which will trigger the boot process of OBP.  By default, the domain will then try to boot right away.  If we don't want that, we can set "auto-boot?" to false.  Finally, we'll use telnet to connect to the console of our newly created guest.  The output of "ldm list" shows us what port has been assigned to mars.  By default, the console service only listens on the loopback interface, so using telnet is not a large security concern here. root@sun # ldm set-variable auto-boot\?=false mars root@sun # ldm bind mars root@sun # ldm start mars root@sun # ldm list NAME STATE FLAGS CONS VCPU MEMORY UTIL UPTIME primary active -n-cv- UART 8 7680M 0.5% 1d 4h 30m mars active -t---- 5000 8 8G 12% 1s root@sun # telnet localhost 5000 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. ~Connecting to console "mars" in group "mars" .... Press ~? for control options .. {0} ok banner SPARC T3-4, No Keyboard Copyright (c) 1998, 2011, Oracle and/or its affiliates. All rights reserved. OpenBoot 4.33.1, 8192 MB memory available, Serial # 87203131. Ethernet address 0:21:28:24:1b:50, Host ID: 85241b50. {0} ok We're done, mars is ready to install Solaris, preferably using AI, of course ;-)  But before we do that, let's have a little look at the OBP environment to see how our virtual devices show up here: {0} ok printenv auto-boot? auto-boot? = false {0} ok printenv boot-device boot-device = disk net {0} ok devalias root /virtual-devices@100/channel-devices@200/disk@0 net0 /virtual-devices@100/channel-devices@200/network@0 net /virtual-devices@100/channel-devices@200/network@0 disk /virtual-devices@100/channel-devices@200/disk@0 virtual-console /virtual-devices/console@1 name aliases We can see that setting the OBP variable "auto-boot?" to false with the ldm command worked.  Of course, we'd normally set this to "true" to allow Solaris to boot right away once the LDom guest is started.  The setting for "boot-device" is the default "disk net", which means OBP would try to boot off the devices pointed to by the aliases "disk" and "net" in that order, which usually means "disk" once Solaris is installed on the disk image.  The actual devices these aliases point to are shown with the command "devalias".  Here, we have one line for both "disk" and "net".  The device paths speak for themselves.  Note that each of these devices has a second alias: "net0" for the network device and "root" for the disk device.  These are the very same names we've given these devices in the control domain with the commands "ldm add-vnet" and "ldm add-vdisk".  Remember this, as it is very useful once you have several dozen disk devices... To wrap this up, in this part we've created a simple guest domain, complete with CPU, memory, boot disk and network connectivity.  This should be enough to get you going.  I will cover all the more advanced features and a little more theoretical background in several follow-on articles.  For some background reading, I'd recommend the following links: LDoms 2.2 Admin Guide: Setting up Guest Domains Virtual Console Server: vntsd manpage - This includes the control sequences and commands available to control the console session. OpenBoot 4.x command reference - All the things you can do at the ok prompt

  Read the article

• How To: Using spatial data with Entity Framework and Connector/Net

  - by GABMARTINEZ

  One of the new features introduced in Entity Framework 5.0 is the incorporation of some new types of data within an Entity Data Model: the spatial data types. These types allow us to perform operations on coordinates values in an easier way. There's no need to add stored routines or functions for every operation among these geometry types, now the user can have the alternative to put this logic on his application or keep it in the database. In the new 6.7.4 version there's also this new feature incorporated to Connector/Net library so our users can start exploring it and could provide us some feedback or comments about this new functionality. Through this tutorial on how to create a Code First Entity Model with a geometry column, we'll show an example on using Geometry types and some common operations when using geometry types inside an application. Requirements: - Connector/Net 6.7.4 - Entity Framework 5.0 version - .NET Framework 4.5 version - Basic understanding on Entity Framework and C# language. - An installed and running instance of MySQL Server 5.5.x or 5.6.10 version- Visual Studio 2012. Step One: Create a new Console Application  Inside Visual Studio select File->New Project menu option and select the Console Application template. Also make sure the .Net 4.5 version is selected so the new features for EF 5.0 will work with the application. Step Two: Add the Entity Framework Package For adding the Entity Framework Package there is more than one option: the package manager console or the Manage Nuget Packages option dialog. If you want to open the Package Manager Console, go to the Tools Menu -> Library Package Manager -> Package Manager Console. On the Package Manager Console Type:Install-Package EntityFrameworkThis will add the reference to the project of the latest released No alpha version of Entity Framework. Step Three: Adding Entity class and DBContext We'll add a simple class that represents a table entity to save some places and its location using a DBGeometry column that will be mapped to a Geometry type in MySQL. After that some operations can be performed using this data. public class MyPlace { [Key] public int Id { get; set; } public string name { get; set; } public DbGeometry location { get; set; } } public class JourneyDb : DbContext { public DbSet<MyPlace> MyPlaces { get; set; } }  Also make sure to add the connection string to the App.Config file as in the example: <?xml version="1.0" encoding="utf-8"?> <configuration>   <configSections>     <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->     <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=5.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />   </configSections>   <startup>     <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />   </startup>   <connectionStrings>     <add name="JourneyDb" connectionString="server=localhost;userid=root;pwd=;database=journeydb" providerName="MySql.Data.MySqlClient"/>   </connectionStrings>   <entityFramework>     </entityFramework> </configuration> Note also that the <entityFramework> section is empty.Step Four: Adding some new records.On the Program.cs file add the following code for the Main method so the Database gets created and also some new data can be added to the new table. This code adds some records containing some determinate locations. After being added a distance function will be used to know how much distance has each location in reference to the Queens Village Station in New York. static void Main(string[] args)    {     using (JourneyDb cxt = new JourneyDb())      {        cxt.Database.Delete();        cxt.Database.Create();         cxt.MyPlaces.Add(new MyPlace()        {          name = "JFK INTERNATIONAL AIRPORT OF NEW YORK",          location = DbGeometry.FromText("POINT(40.644047 -73.782291)"),        });         cxt.MyPlaces.Add(new MyPlace()        {          name = "ALLEY POND PARK",          location = DbGeometry.FromText("POINT(40.745696 -73.742638)"),        });       cxt.MyPlaces.Add(new MyPlace()        {          name = "CUNNINGHAM PARK",          location = DbGeometry.FromText("POINT(40.735031 -73.768387)"),        });         cxt.MyPlaces.Add(new MyPlace()        {          name = "QUEENS VILLAGE STATION",          location = DbGeometry.FromText("POINT(40.717957 -73.736501)"),        });         cxt.SaveChanges();         var points = (from p in cxt.MyPlaces                      select new { p.name, p.location });        foreach (var item in points)       {         Console.WriteLine("Location " + item.name + " has a distance in Km from Queens Village Station " + DbGeometry.FromText("POINT(40.717957 -73.736501)").Distance(item.location) * 100);       }       Console.ReadKey();      }  }}Output : Location JFK INTERNATIONAL AIRPORT OF NEW YORK has a distance from Queens Village Station 8.69448802402959 Km. Location ALLEY POND PARK has a distance from Queens Village Station 2.84097675104912 Km. Location CUNNINGHAM PARK has a distance from Queens Village Station 3.61695793727275 Km. Location QUEENS VILLAGE STATION has a distance from Queens Village Station 0 Km. Conclusion:Adding spatial data to a table is easier than before when having Entity Framework 5.0. This new Entity Framework feature that handles spatial data columns within the Data layer has a lot of integrated functions and methods toease this type of tasks.Notes:This version of Connector/Net is just released as GA so is preatty much stable to be used on a ProductionEnvironment. Please send us your comments or questions using this blog or at the Forums where we keep answering any questions you have about Connector/Net and MySQL Server.A copy of this sample project can be downloaded here. This application does not include any library so you will haveto add them before running it. Happly MySQL/.Net Coding.

  Read the article

• SAS: add comment to lst ouput file

  - by Dan

  In SAS, How do I add comments to my .LST output file. Like adding a comment saying "This is the output for tbl_TestMacro:" right before doing a proc print? So that my output file will read: This is the output for tbl_TestMacro: Obs field1 field2 1 6 8 2 6 9 3 7 0 4 7 1 Instead of just: Obs field1 field2 1 6 8 2 6 9 3 7 0 4 7 1 Thanks, Dan

  Read the article

• Batch Scripting - Listing files with a specific amount of characters in file name

  - by Jane

  I'm creating a batch script for a class and I've hit a roadblock I have to list all text files whose names are up to seven characters long on the whole c: drive - make the listing output in a wide formant - then append to Batch script file output.txt So far I have -- dir c:*txt/w/o/s/p c:/"My Batch Script File Assigment"/"Output"/"Batch Script File Output Data".txt The above does everything except limit the search to files with only 1-7 characters in their name. If anyone could point me in the right direction I would really appreciate it!

  Read the article

• Windows: redirect stdout and stderror to nothing

  - by Ramblingwood

  I have a command I am running produces a ton of output, I want to silence the output without writing to a file. I have used the following to send all output to a file, but again I don't want any file output: command > out.txt 2>&1 I have used command > /bin/null on my CentOS box before, but I can't find a similar thing for windows.

  Read the article

• Multiple pages per sheet (PDF)

  - by smihael

  I use the following commands pdf2ps input.pdf - | psnup -pA4 -4 >> output.ps ps2pdf output.ps output.pdf rm output.ps to merge multiple pages (in this case 4) from input file to one sheet in outupt file. How can I modify pipelining so that I won't have to use 2 commands, but just a single one liner? Is there any other commandline tool that would do the same and can work directly on pdf files?

  Read the article

• Wix light.exe : error LGHT0001: The system cannot open the device or file specified.

  - by Angelo

  Today we build our product with MSBuild /m to build with multiprocess. Before we do a change to heat some files in pre-build event, build with MSBuild multiprocess can be success. Now build is failed with following exception: 124light.exe : error LGHT0001: The system cannot open the device or file specified. (Exception from HRESULT: 0x8007006E) [...MSI.wixproj] Exception Type: System.IO.FileLoadException Stack Trace: at Microsoft.Tools.WindowsInstallerXml.MergeMod.IMsmMerge2.OpenModule(String fileName, Int16 language) at Microsoft.Tools.WindowsInstallerXml.Binder.MergeModules(String tempDatabaseFile, Output output, FileRowCollection fileRows, StringCollection suppressedTableNames) at Microsoft.Tools.WindowsInstallerXml.Binder.BindDatabase(Output output, String databaseFile) at Microsoft.Tools.WindowsInstallerXml.Binder.Bind(Output output, String file) at Microsoft.Tools.WindowsInstallerXml.Tools.Light.Run(String[] args) (Link target) - light.exe : error LGHT0001: The system cannot open the device or file specified. (Exception from HRESULT: 0x8007006E) [...Msi.wixproj] using Wix 3.8

  Read the article

• Chester Devs Presentation and source code &ndash; &lsquo;Event Store - an introduction to a DSD for event sourcing and notifications&rsquo;

  - by Liam Westley

  Originally posted on: http://geekswithblogs.net/twickers/archive/2013/11/11/chester-devs-presentation-and-source-code-ndash-lsquoevent-store.aspxThank you everyone at Chester Devs Thanks to Fran Hoey and all the people from Chester Devs. It was a hard drive up and back but the enthusiasm of the audience, with some great questions does make it worthwhile. Presentation and source code My presentation, source code, Event Store runners and text files containing the various command line parameters used for curl is now available on GitHub; https://github.com/westleyl/ChesterDevs-EventStore. Don’t worry if you don’t have a GitHub account, you don’t need one, you can just click on the Download Zip button on the right hand menu to download all the files as a single ZIP file.  If all you want is the PowerPoint presentation, go to https://github.com/westleyl/ChesterDevs-EventStore/blob/master/Powerpoint/Huddle-EventStore.pptx, and click on the View Raw button. Downloading and installing Event Store and Tools Download Event Store http://download.geteventstore.com – I unzipped these files into C:\EventStore\v2.0.1 Download Curl from http://curl.haxx.se/download.html – I downloaded Win64 Generic (with SSL) and unzipped these files into C:\curl version 7.31.0 Running the tools I used in my presentation Demonstration 1 (running Event Store) You can use one of my Event Store runner command files to run the single node version of Event Store, using default ports of 2213 for HTTP and 1113  for TCP, and with a wildcard HTTP pattern.  Both take a single command line parameter to specify the location of the data and log files.  The runners assume the single node executable is located in C:\EventStore\v2.0.1, and will placed data files and logs beneath C:\EventStore\Data, i.e. RunEventStore.cmd TestData1 This will create data files in C:\EventStore\Data\TestData1\Data and log files in C:\EventStore\Data\TestData1\logs. If, when running Event Store you may see the following message, [03288,15,06:23:00.622] Failed to start http server Access is denied You will either need to run Event Store in an administrator console window, or you can use the netsh command to create a firewall permission to allow HTTP listening (this will need to be run, once, in an administrator console window), netsh http add urlacl url=http://*:2213/ user=liam You can always delete this later by running the delete; netsh http delete urlacl url=http://*:2213/ If you want to confirm that everything is running OK, open the management console in a browser by navigating to http://127.0.0.1:2213. If at any point you are asked for a user name and password use the default of ‘admin’/‘changeit’. Demonstration 2 (reading and adding data, curl) In my second demonstration I used curl directly from the console to read streams, write events and then read back those events. On GitHub I have included is a set of curl commands, CurlCommandLine.txt, and a sample data file, SampleData.json, to load an event into a DDDNorth3 stream. As there is not much data in the Event Store at this point I used the $stats-127.0.0.1:2113 which is a stream containing performance statistics for Event Store and is updated every 30 seconds (default). Demonstration 3 (projections) On GitHub I have included a sample projection, Projection-ByRoom.txt, which will create streams based on the room on which a session was held on the DDDNorth3 agenda. Browse to the management console, http://127.0.0.1:2213.  Click on Projections, New Projection, give it a name, Sessions-ByRoom, and copy in the JavaScript in the Projection-ByRoom.txt file.  Select Continuous, tick Emit Enabled and then click on Post. It should run immediately. You may by challenged for the administration login for the management console, if so use the default user name and password; 'admin'/'changeit'. Demonstration 4 (C# client) The final demonstration was the Visual Studio 2012 project using the Event Store client – referenced directly as C:\EventStore\v2.0.1\EventStore.ClientAPI.dll, although you can switch this to the latest Event Store client NuGet package. The source code provides a console app for viewing projections with the projection manager (HTTP connection), as well as containing a full set of data for the entire DDDNorth3 agenda.  It also deals with the strategy for reading newest events backwards to older events and ignoring older events that have been superseded. Resources Event Store home page: http://www.geteventstore.com/ Event Store source code on GitHub: https://github.com/eventstore/eventstore Event Store documentation on GitHub: https://github.com/eventstore/eventstore/wiki (includes index to @RobAshton’s blog series on Event Store at https://github.com/eventstore/eventstore/wiki#rob-ashton---projections-series) Event Store forum in Google Groups: https://groups.google.com/forum/?fromgroups#!forum/event-store TopShelf Windows service wrapper is available on github: https://gist.github.com/trbngr/5083266

  Read the article

• DDD North 3 Presentation and source code &ndash; &lsquo;Event Store - an introduction to a DSD for event sourcing and notifications&rsquo;

  - by Liam Westley

  Originally posted on: http://geekswithblogs.net/twickers/archive/2013/10/15/ddd-north-3-presentation-and-source-code-ndash-lsquoevent-store.aspxThank you everyone at DDD North Thanks to all the people who helped organise the cracking conference that is DDD North 3, returning to Sunderland, and the great facilities at the University of Sunderland, and the fine drinks reception at Sunderland Software City.  The whole event wouldn’t be possible without the sponsors who ensured over 400 people were kept fed and watered so they could enjoy the impressive range of sessions. And lastly, a thank you to all those delegates who gave up their free time on a Saturday to spend a day dashing between lecture rooms, including a late change to my room which saw 40 people having to brave a journey between buildings in the fine drizzle. The enthusiasm from the delegates always helps recharge my geek batteries. Presentation and source code My presentation, source code, Event Store runners and text files containing the various command line parameters used for curl is now available on GitHub; https://github.com/westleyl/DDDNorth3-EventStore. Don’t worry if you don’t have a GitHub account, you don’t need one, you can just click on the Download Zip button on the right hand menu to download all the files as a single ZIP file.  If all you want is the PowerPoint presentation, go to https://github.com/westleyl/DDDNorth3-EventStore/blob/master/Powerpoint/DDDNorth-EventStore.pptx, and click on the View Raw button. Downloading and installing Event Store and Tools Download Event Store http://download.geteventstore.com – I unzipped these files into C:\EventStore\v2.0.1 Download Curl from http://curl.haxx.se/download.html – I downloaded Win64 Generic (with SSL) and unzipped these files into C:\curl version 7.31.0 Running the tools I used in my presentation Demonstration 1 (running Event Store) You can use one of my Event Store runner command files to run the single node version of Event Store, using default ports of 2213 for HTTP and 1113  for TCP, and with a wildcard HTTP pattern.  Both take a single command line parameter to specify the location of the data and log files.  The runners assume the single node executable is located in C:\EventStore\v2.0.1, and will placed data files and logs beneath C:\EventStore\Data, i.e. RunEventStore.cmd TestData1 This will create data files in C:\EventStore\Data\TestData1\Data and log files in C:\EventStore\Data\TestData1\logs. If, when running Event Store you may see the following message, [03288,15,06:23:00.622] Failed to start http server Access is denied You will either need to run Event Store in an administrator console window, or you can use the netsh command to create a firewall permission to allow HTTP listening (this will need to be run, once, in an administrator console window), netsh http add urlacl url=http://*:2213/ user=liam You can always delete this later by running the delete; netsh http delete urlacl url=http://*:2213/ If you want to confirm that everything is running OK, open the management console in a browser by navigating to http://127.0.0.1:2213. If at any point you are asked for a user name and password use the default of ‘admin’/‘changeit’.   Demonstration 2 (reading and adding data, curl) In my second demonstration I used curl directly from the console to read streams, write events and then read back those events. On GitHub I have included is a set of curl commands, CurlCommandLine.txt, and a sample data file, SampleData.json, to load an event into a DDDNorth3 stream. As there is not much data in the Event Store at this point I used the $stats-127.0.0.1:2113 which is a stream containing performance statistics for Event Store and is updated every 30 seconds (default). Demonstration 3 (projections) On GitHub I have included a sample projection, Projection-ByRoom.txt, which will create streams based on the room on which a session was held on the DDDNorth3 agenda. Browse to the management console, http://127.0.0.1:2213.  Click on Projections, New Projection, give it a name, Sessions-ByRoom, and copy in the JavaScript in the Projection-ByRoom.txt file.  Select Continuous, tick Emit Enabled and then click on Post. It should run immediately. You may by challenged for the administration login for the management console, if so use the default user name and password; 'admin'/'changeit'.   Demonstration 4 (C# client) The final demonstration was the Visual Studio 2012 project using the Event Store client – referenced directly as C:\EventStore\v2.0.1\EventStore.ClientAPI.dll, although you can switch this to the latest Event Store client NuGet package. The source code provides a console app for viewing projections with the projection manager (HTTP connection), as well as containing a full set of data for the entire DDDNorth3 agenda.  It also deals with the strategy for reading newest events backwards to older events and ignoring older events that have been superseded. Resources Event Store home page: http://www.geteventstore.com/ Event Store source code on GitHub: https://github.com/eventstore/eventstore Event Store documentation on GitHub: https://github.com/eventstore/eventstore/wiki (includes index to @RobAshton’s blog series on Event Store at https://github.com/eventstore/eventstore/wiki#rob-ashton---projections-series) Event Store forum in Google Groups: https://groups.google.com/forum/?fromgroups#!forum/event-store TopShelf Windows service wrapper is available on github: https://gist.github.com/trbngr/5083266

  Read the article

• Subjective question...would you use the Action delegate to avoid duplication of code?

  - by Seth Spearman

  Hello, I just asked a question that helps about using generics (or polymorphism) to avoid duplication of code. I am really trying to follow the DRY principle. So I just ran into the following code... Sub OutputDataToExcel() OutputLine("Output DataBlocks", 1) OutputDataBlocks() OutputLine("") OutputLine("Output Numbered Inventory", 1) OutputNumberedInventory() OutputLine("") OutputLine("Output Item Summaries", 1) OutputItemSummaries() OutputLine("") End Sub Should I rewrite this code to be as follows using the Action delegate... Sub OutputDataToExcel() OutputData("Output DataBlocks", New Action(AddressOf OutputDataBlocks)) OutputData("Output Numbered Inventory", New Action(AddressOf OutputNumberedInventory)) OutputData("Output Item Summaries", New Action(AddressOf OutputItemSummaries)) End Sub Sub OutputData(ByVal outputDescription As String, ByVal outputType As Action) OutputLine(outputDescription, 1) outputType() OutputLine("") End Sub I realize this question is subjective. I am just wondering about how religiously you follow DRY. Would you do this? Seth

  Read the article

• Code Golf - p day

  - by gnibbler

  The Challenge The shortest code by character count to display a representation of a circle of radius R using the *character, followed by an approximation of p. Input is a single number, R. Since most computers seem to have almost 2:1 ratio you should only output lines where y is odd. The approximation of p is given by dividing twice the number of * characters by R². The approximation should be correct to at least 6 significant digits. Leading or trailing zeros are permitted, so for example any of 3, 3.000000, 003 is accepted for the inputs of 2 and 4. Code count includes input/output (i.e., full program). Test Cases Input 2 Output *** *** 3.0 Input 4 Output ***** ******* ******* ***** 3.0 Input 8 Output ******* ************* *************** *************** *************** *************** ************* ******* 3.125 Input 10 Output ********* *************** ***************** ******************* ******************* ******************* ******************* ***************** *************** ********* 3.16

  Read the article

• Code Golf - PI day

  - by gnibbler

  The Challenge The shortest code by character count to display a representation of a circle of radius R using the *character. Followed by an approximation of pi Input is a single number, R Since most computers seem to have almost 2:1 ratio you should only output lines where y is odd. The approximation of pi is given by dividing the twice the number of * characters by R squared. The approximation should be correct to at least 6 significant digits. Leading or trailing zeros are permitted, so for example any of 3,3.000000,003 is accepted for the inputs of 2 and 4 Code count includes input/output (i.e full program). Test Cases Input 2 Output *** *** 3.0 Input 4 Output ***** ******* ******* ***** 3.0 Input 8 Output ******* ************* *************** *************** *************** *************** ************* ******* 3.125 Input 10 Output ********* *************** ***************** ******************* ******************* ******************* ******************* ***************** *************** ********* 3.16

  Read the article

• Get and Set property accessors are ‘actually’ methods

  - by nmarun

  Well, they are ‘special’ methods, but they indeed are methods. See the class below: 1: public class Person 2: { 3: private string _name; 4:  5: public string Name 6: { 7: get 8: { 9: return _name; 10: } 11: set 12: { 13: if (value == "aaa") 14: { 15: throw new ArgumentException("Invalid Name"); 16: } 17: _name = value; 18: } 19: } 20:  21: public void Save() 22: { 23: Console.WriteLine("Saving..."); 24: } 25: } Ok, so a class with a field, a property with the get and set accessors and a method. Now my calling code says: 1: static void Main() 2: { 3: try 4: { 5: Person person1 = new Person 6: { 7: Name = "aaa", 8: }; 9:  10: } 11: catch (Exception ex) 12: { 13: Console.WriteLine(ex.Message); 14: Console.WriteLine(ex.StackTrace); 15: Console.WriteLine("--------------------"); 16: } 17: } When the code is run, you’ll get the following exception message displayed: Now, you see the first line of the stack trace where it says that the exception was thrown in the method set_Name(String value). Wait a minute, we have not declared any method with that name in our Person class. Oh no, we actually have. When you create a property, this is what happens behind the screen. The CLR creates two methods for each get and set property accessor. Let’s look at the signature once again: set_Name(String value) This also tells you where the ‘value’ keyword comes from in our set property accessor. You’re actually wiring up a method parameter to a field. 1: set 2: { 3: if (value == "aaa") 4: { 5: throw new ArgumentException("Invalid Name"); 6: } 7: _name = value; 8: } Digging deeper on this, I ran the ILDasm tool and this is what I see: We see the ‘free’ constructor (named .ctor) that the compiler gives us, the _name field, the Name property and the Save method. We also see the get_Name and set_Name methods. In order to compare the Save and the set_Name methods, I double-clicked on the two methods and this is what I see: The ‘.method’ keyword tells that both Save and set_Name are both methods (no guessing there!). Seeing the set_Name method as a public method did kinda surprise me. So I said, why can’t I do a person1.set_Name(“abc”) since it is declared as public. This cannot be done because the get_Name and set_Name methods have an extra attribute called ‘specialname’. This attribute is used to identify an IL (Intermediate Language) token that can be treated with special care by the .net language. So the thumb-rule is that any method with the ‘specialname’ attribute cannot be generally called / invoked by the user (a simple test using intellisense proves this). Their functionality is exposed through other ways. In our case, this is done through the property itself. The same concept gets extended to constructors as well making them special methods too. These so-called ‘special’ methods can be identified through reflection. 1: static void ReflectOnPerson() 2: { 3: Type personType = typeof(Person); 4:  5: MethodInfo[] methods = personType.GetMethods(); 6:  7: for (int i = 0; i < methods.Length; i++) 8: { 9: Console.Write("Method: {0}", methods[i].Name); 10: // Determine whether or not each method is a special name. 11: if (methods[i].IsSpecialName) 12: { 13: Console.Write(" has 'SpecialName' attribute"); 14: } 15: Console.WriteLine(); 16: } 17: } Line 11 shows the ‘IsSpecialName’ boolean property. So a method with a ‘specialname’ attribute gets mapped to the IsSpecialName property. The output is displayed as: Wuhuuu! There they are.. our special guests / methods. Verdict: Getting to know the internals… helps!

  Read the article

< Previous Page | 123 124 125 126 127 128 129 130 131 132 133 134  | Next Page >