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  • Quick guide to Oracle IRM 11g: Classification design

    - by Simon Thorpe
    Quick guide to Oracle IRM 11g indexThis is the final article in the quick guide to Oracle IRM. If you've followed everything prior you will now have a fully functional and tested Information Rights Management service. It doesn't matter if you've been following the 10g or 11g guide as this next article is common to both. ContentsWhy this is the most important part... Understanding the classification and standard rights model Identifying business use cases Creating an effective IRM classification modelOne single classification across the entire businessA context for each and every possible granular use caseWhat makes a good context? Deciding on the use of roles in the context Reviewing the features and security for context roles Summary Why this is the most important part...Now the real work begins, installing and getting an IRM system running is as simple as following instructions. However to actually have an IRM technology easily protecting your most sensitive information without interfering with your users existing daily work flows and be able to scale IRM across the entire business, requires thought into how confidential documents are created, used and distributed. This article is going to give you the information you need to ask the business the right questions so that you can deploy your IRM service successfully. The IRM team here at Oracle have over 10 years of experience in helping customers and it is important you understand the following to be successful in securing access to your most confidential information. Whatever you are trying to secure, be it mergers and acquisitions information, engineering intellectual property, health care documentation or financial reports. No matter what type of user is going to access the information, be they employees, contractors or customers, there are common goals you are always trying to achieve.Securing the content at the earliest point possible and do it automatically. Removing the dependency on the user to decide to secure the content reduces the risk of mistakes significantly and therefore results a more secure deployment. K.I.S.S. (Keep It Simple Stupid) Reduce complexity in the rights/classification model. Oracle IRM lets you make changes to access to documents even after they are secured which allows you to start with a simple model and then introduce complexity once you've understood how the technology is going to be used in the business. After an initial learning period you can review your implementation and start to make informed decisions based on user feedback and administration experience. Clearly communicate to the user, when appropriate, any changes to their existing work practice. You must make every effort to make the transition to sealed content as simple as possible. For external users you must help them understand why you are securing the documents and inform them the value of the technology to both your business and them. Before getting into the detail, I must pay homage to Martin White, Vice President of client services in SealedMedia, the company Oracle acquired and who created Oracle IRM. In the SealedMedia years Martin was involved with every single customer and was key to the design of certain aspects of the IRM technology, specifically the context model we will be discussing here. Listening carefully to customers and understanding the flexibility of the IRM technology, Martin taught me all the skills of helping customers build scalable, effective and simple to use IRM deployments. No matter how well the engineering department designed the software, badly designed and poorly executed projects can result in difficult to use and manage, and ultimately insecure solutions. The advice and information that follows was born with Martin and he's still delivering IRM consulting with customers and can be found at www.thinkers.co.uk. It is from Martin and others that Oracle not only has the most advanced, scalable and usable document security solution on the market, but Oracle and their partners have the most experience in delivering successful document security solutions. Understanding the classification and standard rights model The goal of any successful IRM deployment is to balance the increase in security the technology brings without over complicating the way people use secured content and avoid a significant increase in administration and maintenance. With Oracle it is possible to automate the protection of content, deploy the desktop software transparently and use authentication methods such that users can open newly secured content initially unaware the document is any different to an insecure one. That is until of course they attempt to do something for which they don't have any rights, such as copy and paste to an insecure application or try and print. Central to achieving this objective is creating a classification model that is simple to understand and use but also provides the right level of complexity to meet the business needs. In Oracle IRM the term used for each classification is a "context". A context defines the relationship between.A group of related documents The people that use the documents The roles that these people perform The rights that these people need to perform their role The context is the key to the success of Oracle IRM. It provides the separation of the role and rights of a user from the content itself. Documents are sealed to contexts but none of the rights, user or group information is stored within the content itself. Sealing only places information about the location of the IRM server that sealed it, the context applied to the document and a few other pieces of metadata that pertain only to the document. This important separation of rights from content means that millions of documents can be secured against a single classification and a user needs only one right assigned to be able to access all documents. If you have followed all the previous articles in this guide, you will be ready to start defining contexts to which your sensitive information will be protected. But before you even start with IRM, you need to understand how your own business uses and creates sensitive documents and emails. Identifying business use cases Oracle is able to support multiple classification systems, but usually there is one single initial need for the technology which drives a deployment. This need might be to protect sensitive mergers and acquisitions information, engineering intellectual property, financial documents. For this and every subsequent use case you must understand how users create and work with documents, to who they are distributed and how the recipients should interact with them. A successful IRM deployment should start with one well identified use case (we go through some examples towards the end of this article) and then after letting this use case play out in the business, you learn how your users work with content, how well your communication to the business worked and if the classification system you deployed delivered the right balance. It is at this point you can start rolling the technology out further. Creating an effective IRM classification model Once you have selected the initial use case you will address with IRM, you need to design a classification model that defines the access to secured documents within the use case. In Oracle IRM there is an inbuilt classification system called the "context" model. In Oracle IRM 11g it is possible to extend the server to support any rights classification model, but the majority of users who are not using an application integration (such as Oracle IRM within Oracle Beehive) are likely to be starting out with the built in context model. Before looking at creating a classification system with IRM, it is worth reviewing some recognized standards and methods for creating and implementing security policy. A very useful set of documents are the ISO 17799 guidelines and the SANS security policy templates. First task is to create a context against which documents are to be secured. A context consists of a group of related documents (all top secret engineering research), a list of roles (contributors and readers) which define how users can access documents and a list of users (research engineers) who have been given a role allowing them to interact with sealed content. Before even creating the first context it is wise to decide on a philosophy which will dictate the level of granularity, the question is, where do you start? At a department level? By project? By technology? First consider the two ends of the spectrum... One single classification across the entire business Imagine that instead of having separate contexts, one for engineering intellectual property, one for your financial data, one for human resources personally identifiable information, you create one context for all documents across the entire business. Whilst you may have immediate objections, there are some significant benefits in thinking about considering this. Document security classification decisions are simple. You only have one context to chose from! User provisioning is simple, just make sure everyone has a role in the only context in the business. Administration is very low, if you assign rights to groups from the business user repository you probably never have to touch IRM administration again. There are however some obvious downsides to this model.All users in have access to all IRM secured content. So potentially a sales person could access sensitive mergers and acquisition documents, if they can get their hands on a copy that is. You cannot delegate control of different documents to different parts of the business, this may not satisfy your regulatory requirements for the separation and delegation of duties. Changing a users role affects every single document ever secured. Even though it is very unlikely a business would ever use one single context to secure all their sensitive information, thinking about this scenario raises one very important point. Just having one single context and securing all confidential documents to it, whilst incurring some of the problems detailed above, has one huge value. Once secured, IRM protected content can ONLY be accessed by authorized users. Just think of all the sensitive documents in your business today, imagine if you could ensure that only everyone you trust could open them. Even if an employee lost a laptop or someone accidentally sent an email to the wrong recipient, only the right people could open that file. A context for each and every possible granular use case Now let's think about the total opposite of a single context design. What if you created a context for each and every single defined business need and created multiple contexts within this for each level of granularity? Let's take a use case where we need to protect engineering intellectual property. Imagine we have 6 different engineering groups, and in each we have a research department, a design department and manufacturing. The company information security policy defines 3 levels of information sensitivity... restricted, confidential and top secret. Then let's say that each group and department needs to define access to information from both internal and external users. Finally add into the mix that they want to review the rights model for each context every financial quarter. This would result in a huge amount of contexts. For example, lets just look at the resulting contexts for one engineering group. Q1FY2010 Restricted Internal - Engineering Group 1 - Research Q1FY2010 Restricted Internal - Engineering Group 1 - Design Q1FY2010 Restricted Internal - Engineering Group 1 - Manufacturing Q1FY2010 Restricted External- Engineering Group 1 - Research Q1FY2010 Restricted External - Engineering Group 1 - Design Q1FY2010 Restricted External - Engineering Group 1 - Manufacturing Q1FY2010 Confidential Internal - Engineering Group 1 - Research Q1FY2010 Confidential Internal - Engineering Group 1 - Design Q1FY2010 Confidential Internal - Engineering Group 1 - Manufacturing Q1FY2010 Confidential External - Engineering Group 1 - Research Q1FY2010 Confidential External - Engineering Group 1 - Design Q1FY2010 Confidential External - Engineering Group 1 - Manufacturing Q1FY2010 Top Secret Internal - Engineering Group 1 - Research Q1FY2010 Top Secret Internal - Engineering Group 1 - Design Q1FY2010 Top Secret Internal - Engineering Group 1 - Manufacturing Q1FY2010 Top Secret External - Engineering Group 1 - Research Q1FY2010 Top Secret External - Engineering Group 1 - Design Q1FY2010 Top Secret External - Engineering Group 1 - Manufacturing Now multiply the above by 6 for each engineering group, 18 contexts. You are then creating/reviewing another 18 every 3 months. After a year you've got 72 contexts. What would be the advantages of such a complex classification model? You can satisfy very granular rights requirements, for example only an authorized engineering group 1 researcher can create a top secret report for access internally, and his role will be reviewed on a very frequent basis. Your business may have very complex rights requirements and mapping this directly to IRM may be an obvious exercise. The disadvantages of such a classification model are significant...Huge administrative overhead. Someone in the business must manage, review and administrate each of these contexts. If the engineering group had a single administrator, they would have 72 classifications to reside over each year. From an end users perspective life will be very confusing. Imagine if a user has rights in just 6 of these contexts. They may be able to print content from one but not another, be able to edit content in 2 contexts but not the other 4. Such confusion at the end user level causes frustration and resistance to the use of the technology. Increased synchronization complexity. Imagine a user who after 3 years in the company ends up with over 300 rights in many different contexts across the business. This would result in long synchronization times as the client software updates all your offline rights. Hard to understand who can do what with what. Imagine being the VP of engineering and as part of an internal security audit you are asked the question, "What rights to researchers have to our top secret information?". In this complex model the answer is not simple, it would depend on many roles in many contexts. Of course this example is extreme, but it highlights that trying to build many barriers in your business can result in a nightmare of administration and confusion amongst users. In the real world what we need is a balance of the two. We need to seek an optimum number of contexts. Too many contexts are unmanageable and too few contexts does not give fine enough granularity. What makes a good context? Good context design derives mainly from how well you understand your business requirements to secure access to confidential information. Some customers I have worked with can tell me exactly the documents they wish to secure and know exactly who should be opening them. However there are some customers who know only of the government regulation that requires them to control access to certain types of information, they don't actually know where the documents are, how they are created or understand exactly who should have access. Therefore you need to know how to ask the business the right questions that lead to information which help you define a context. First ask these questions about a set of documentsWhat is the topic? Who are legitimate contributors on this topic? Who are the authorized readership? If the answer to any one of these is significantly different, then it probably merits a separate context. Remember that sealed documents are inherently secure and as such they cannot leak to your competitors, therefore it is better sealed to a broad context than not sealed at all. Simplicity is key here. Always revert to the first extreme example of a single classification, then work towards essential complexity. If there is any doubt, always prefer fewer contexts. Remember, Oracle IRM allows you to change your mind later on. You can implement a design now and continue to change and refine as you learn how the technology is used. It is easy to go from a simple model to a more complex one, it is much harder to take a complex model that is already embedded in the work practice of users and try to simplify it. It is also wise to take a single use case and address this first with the business. Don't try and tackle many different problems from the outset. Do one, learn from the process, refine it and then take what you have learned into the next use case, refine and continue. Once you have a good grasp of the technology and understand how your business will use it, you can then start rolling out the technology wider across the business. Deciding on the use of roles in the context Once you have decided on that first initial use case and a context to create let's look at the details you need to decide upon. For each context, identify; Administrative rolesBusiness owner, the person who makes decisions about who may or may not see content in this context. This is often the person who wanted to use IRM and drove the business purchase. They are the usually the person with the most at risk when sensitive information is lost. Point of contact, the person who will handle requests for access to content. Sometimes the same as the business owner, sometimes a trusted secretary or administrator. Context administrator, the person who will enact the decisions of the Business Owner. Sometimes the point of contact, sometimes a trusted IT person. Document related rolesContributors, the people who create and edit documents in this context. Reviewers, the people who are involved in reviewing documents but are not trusted to secure information to this classification. This role is not always necessary. (See later discussion on Published-work and Work-in-Progress) Readers, the people who read documents from this context. Some people may have several of the roles above, which is fine. What you are trying to do is understand and define how the business interacts with your sensitive information. These roles obviously map directly to roles available in Oracle IRM. Reviewing the features and security for context roles At this point we have decided on a classification of information, understand what roles people in the business will play when administrating this classification and how they will interact with content. The final piece of the puzzle in getting the information for our first context is to look at the permissions people will have to sealed documents. First think why are you protecting the documents in the first place? It is to prevent the loss of leaking of information to the wrong people. To control the information, making sure that people only access the latest versions of documents. You are not using Oracle IRM to prevent unauthorized people from doing legitimate work. This is an important point, with IRM you can erect many barriers to prevent access to content yet too many restrictions and authorized users will often find ways to circumvent using the technology and end up distributing unprotected originals. Because IRM is a security technology, it is easy to get carried away restricting different groups. However I would highly recommend starting with a simple solution with few restrictions. Ensure that everyone who reasonably needs to read documents can do so from the outset. Remember that with Oracle IRM you can change rights to content whenever you wish and tighten security. Always return to the fact that the greatest value IRM brings is that ONLY authorized users can access secured content, remember that simple "one context for the entire business" model. At the start of the deployment you really need to aim for user acceptance and therefore a simple model is more likely to succeed. As time passes and users understand how IRM works you can start to introduce more restrictions and complexity. Another key aspect to focus on is handling exceptions. If you decide on a context model where engineering can only access engineering information, and sales can only access sales data. Act quickly when a sales manager needs legitimate access to a set of engineering documents. Having a quick and effective process for permitting other people with legitimate needs to obtain appropriate access will be rewarded with acceptance from the user community. These use cases can often be satisfied by integrating IRM with a good Identity & Access Management technology which simplifies the process of assigning users the correct business roles. The big print issue... Printing is often an issue of contention, users love to print but the business wants to ensure sensitive information remains in the controlled digital world. There are many cases of physical document loss causing a business pain, it is often overlooked that IRM can help with this issue by limiting the ability to generate physical copies of digital content. However it can be hard to maintain a balance between security and usability when it comes to printing. Consider the following points when deciding about whether to give print rights. Oracle IRM sealed documents can contain watermarks that expose information about the user, time and location of access and the classification of the document. This information would reside in the printed copy making it easier to trace who printed it. Printed documents are slower to distribute in comparison to their digital counterparts, so time sensitive information in printed format may present a lower risk. Print activity is audited, therefore you can monitor and react to users abusing print rights. Summary In summary it is important to think carefully about the way you create your context model. As you ask the business these questions you may get a variety of different requirements. There may be special projects that require a context just for sensitive information created during the lifetime of the project. There may be a department that requires all information in the group is secured and you might have a few senior executives who wish to use IRM to exchange a small number of highly sensitive documents with a very small number of people. Oracle IRM, with its very flexible context classification system, can support all of these use cases. The trick is to introducing the complexity to deliver them at the right level. In another article i'm working on I will go through some examples of how Oracle IRM might map to existing business use cases. But for now, this article covers all the important questions you need to get your IRM service deployed and successfully protecting your most sensitive information.

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  • URL Routing in ASP.NET 4.0

    In the .NET Framework 3.5 SP1, Microsoft introduced ASP.NET Routing, which decouples the URL of a resource from the physical file on the web server. With ASP.NET Routing you, the developer, define routing rules map route patterns to a class that generates the content. For example, you might indicate that the URL Categories/CategoryName maps to a class that takes the CategoryName and generates HTML that lists that category's products in a grid. With such a mapping, users could view products for the Beverages category by visiting www.yoursite.com/Categories/Beverages. In .NET 3.5 SP1, ASP.NET Routing was primarily designed for ASP.NET MVC applications, although as discussed in Using ASP.NET Routing Without ASP.NET MVC it is possible to implement ASP.NET Routing in a Web Forms application, as well. However, implementing ASP.NET Routing in a Web Forms application involves a bit of seemingly excessive legwork. In a Web Forms scenario we typically want to map a routing pattern to an actual ASP.NET page. To do so we need to create a route handler class that is invoked when the routing URL is requested and, in a sense, dispatches the request to the appropriate ASP.NET page. For instance, to map a route to a physical file, such as mapping Categories/CategoryName to ShowProductsByCategory.aspx - requires three steps: (1) Define the mapping in Global.asax, which maps a route pattern to a route handler class; (2) Create the route handler class, which is responsible for parsing the URL, storing any route parameters into some location that is accessible to the target page (such as HttpContext.Items), and returning an instance of the target page or HTTP Handler that handles the requested route; and (3) writing code in the target page to grab the route parameters and use them in rendering its content. Given how much effort it took to just read the preceding sentence (let alone write it) you can imagine that implementing ASP.NET Routing in a Web Forms application is not necessarily the most straightforward task. The good news is that ASP.NET 4.0 has greatly simplified ASP.NET Routing for Web Form applications by adding a number of classes and helper methods that can be used to encapsulate the aforementioned complexity. With ASP.NET 4.0 it's easier to define the routing rules and there's no need to create a custom route handling class. This article details these enhancements. Read on to learn more! Read More >

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  • Basic Spatial Data with SQL Server and Entity Framework 5.0

    - by Rick Strahl
    In my most recent project we needed to do a bit of geo-spatial referencing. While spatial features have been in SQL Server for a while using those features inside of .NET applications hasn't been as straight forward as could be, because .NET natively doesn't support spatial types. There are workarounds for this with a few custom project like SharpMap or a hack using the Sql Server specific Geo types found in the Microsoft.SqlTypes assembly that ships with SQL server. While these approaches work for manipulating spatial data from .NET code, they didn't work with database access if you're using Entity Framework. Other ORM vendors have been rolling their own versions of spatial integration. In Entity Framework 5.0 running on .NET 4.5 the Microsoft ORM finally adds support for spatial types as well. In this post I'll describe basic geography features that deal with single location and distance calculations which is probably the most common usage scenario. SQL Server Transact-SQL Syntax for Spatial Data Before we look at how things work with Entity framework, lets take a look at how SQL Server allows you to use spatial data to get an understanding of the underlying semantics. The following SQL examples should work with SQL 2008 and forward. Let's start by creating a test table that includes a Geography field and also a pair of Long/Lat fields that demonstrate how you can work with the geography functions even if you don't have geography/geometry fields in the database. Here's the CREATE command:CREATE TABLE [dbo].[Geo]( [id] [int] IDENTITY(1,1) NOT NULL, [Location] [geography] NULL, [Long] [float] NOT NULL, [Lat] [float] NOT NULL ) Now using plain SQL you can insert data into the table using geography::STGeoFromText SQL CLR function:insert into Geo( Location , long, lat ) values ( geography::STGeomFromText ('POINT(-121.527200 45.712113)', 4326), -121.527200, 45.712113 ) insert into Geo( Location , long, lat ) values ( geography::STGeomFromText ('POINT(-121.517265 45.714240)', 4326), -121.517265, 45.714240 ) insert into Geo( Location , long, lat ) values ( geography::STGeomFromText ('POINT(-121.511536 45.714825)', 4326), -121.511536, 45.714825) The STGeomFromText function accepts a string that points to a geometric item (a point here but can also be a line or path or polygon and many others). You also need to provide an SRID (Spatial Reference System Identifier) which is an integer value that determines the rules for how geography/geometry values are calculated and returned. For mapping/distance functionality you typically want to use 4326 as this is the format used by most mapping software and geo-location libraries like Google and Bing. The spatial data in the Location field is stored in binary format which looks something like this: Once the location data is in the database you can query the data and do simple distance computations very easily. For example to calculate the distance of each of the values in the database to another spatial point is very easy to calculate. Distance calculations compare two points in space using a direct line calculation. For our example I'll compare a new point to all the points in the database. Using the Location field the SQL looks like this:-- create a source point DECLARE @s geography SET @s = geography:: STGeomFromText('POINT(-121.527200 45.712113)' , 4326); --- return the ids select ID, Location as Geo , Location .ToString() as Point , @s.STDistance( Location) as distance from Geo order by distance The code defines a new point which is the base point to compare each of the values to. You can also compare values from the database directly, but typically you'll want to match a location to another location and determine the difference for which you can use the geography::STDistance function. This query produces the following output: The STDistance function returns the straight line distance between the passed in point and the point in the database field. The result for SRID 4326 is always in meters. Notice that the first value passed was the same point so the difference is 0. The other two points are two points here in town in Hood River a little ways away - 808 and 1256 meters respectively. Notice also that you can order the result by the resulting distance, which effectively gives you results that are ordered radially out from closer to further away. This is great for searches of points of interest near a central location (YOU typically!). These geolocation functions are also available to you if you don't use the Geography/Geometry types, but plain float values. It's a little more work, as each point has to be created in the query using the string syntax, but the following code doesn't use a geography field but produces the same result as the previous query.--- using float fields select ID, geography::STGeomFromText ('POINT(' + STR (long, 15,7 ) + ' ' + Str(lat ,15, 7) + ')' , 4326), geography::STGeomFromText ('POINT(' + STR (long, 15,7 ) + ' ' + Str(lat ,15, 7) + ')' , 4326). ToString(), @s.STDistance( geography::STGeomFromText ('POINT(' + STR(long ,15, 7) + ' ' + Str(lat ,15, 7) + ')' , 4326)) as distance from geo order by distance Spatial Data in the Entity Framework Prior to Entity Framework 5.0 on .NET 4.5 consuming of the data above required using stored procedures or raw SQL commands to access the spatial data. In Entity Framework 5 however, Microsoft introduced the new DbGeometry and DbGeography types. These immutable location types provide a bunch of functionality for manipulating spatial points using geometry functions which in turn can be used to do common spatial queries like I described in the SQL syntax above. The DbGeography/DbGeometry types are immutable, meaning that you can't write to them once they've been created. They are a bit odd in that you need to use factory methods in order to instantiate them - they have no constructor() and you can't assign to properties like Latitude and Longitude. Creating a Model with Spatial Data Let's start by creating a simple Entity Framework model that includes a Location property of type DbGeography: public class GeoLocationContext : DbContext { public DbSet<GeoLocation> Locations { get; set; } } public class GeoLocation { public int Id { get; set; } public DbGeography Location { get; set; } public string Address { get; set; } } That's all there's to it. When you run this now against SQL Server, you get a Geography field for the Location property, which looks the same as the Location field in the SQL examples earlier. Adding Spatial Data to the Database Next let's add some data to the table that includes some latitude and longitude data. An easy way to find lat/long locations is to use Google Maps to pinpoint your location, then right click and click on What's Here. Click on the green marker to get the GPS coordinates. To add the actual geolocation data create an instance of the GeoLocation type and use the DbGeography.PointFromText() factory method to create a new point to assign to the Location property:[TestMethod] public void AddLocationsToDataBase() { var context = new GeoLocationContext(); // remove all context.Locations.ToList().ForEach( loc => context.Locations.Remove(loc)); context.SaveChanges(); var location = new GeoLocation() { // Create a point using native DbGeography Factory method Location = DbGeography.PointFromText( string.Format("POINT({0} {1})", -121.527200,45.712113) ,4326), Address = "301 15th Street, Hood River" }; context.Locations.Add(location); location = new GeoLocation() { Location = CreatePoint(45.714240, -121.517265), Address = "The Hatchery, Bingen" }; context.Locations.Add(location); location = new GeoLocation() { // Create a point using a helper function (lat/long) Location = CreatePoint(45.708457, -121.514432), Address = "Kaze Sushi, Hood River" }; context.Locations.Add(location); location = new GeoLocation() { Location = CreatePoint(45.722780, -120.209227), Address = "Arlington, OR" }; context.Locations.Add(location); context.SaveChanges(); } As promised, a DbGeography object has to be created with one of the static factory methods provided on the type as the Location.Longitude and Location.Latitude properties are read only. Here I'm using PointFromText() which uses a "Well Known Text" format to specify spatial data. In the first example I'm specifying to create a Point from a longitude and latitude value, using an SRID of 4326 (just like earlier in the SQL examples). You'll probably want to create a helper method to make the creation of Points easier to avoid that string format and instead just pass in a couple of double values. Here's my helper called CreatePoint that's used for all but the first point creation in the sample above:public static DbGeography CreatePoint(double latitude, double longitude) { var text = string.Format(CultureInfo.InvariantCulture.NumberFormat, "POINT({0} {1})", longitude, latitude); // 4326 is most common coordinate system used by GPS/Maps return DbGeography.PointFromText(text, 4326); } Using the helper the syntax becomes a bit cleaner, requiring only a latitude and longitude respectively. Note that my method intentionally swaps the parameters around because Latitude and Longitude is the common format I've seen with mapping libraries (especially Google Mapping/Geolocation APIs with their LatLng type). When the context is changed the data is written into the database using the SQL Geography type which looks the same as in the earlier SQL examples shown. Querying Once you have some location data in the database it's now super easy to query the data and find out the distance between locations. A common query is to ask for a number of locations that are near a fixed point - typically your current location and order it by distance. Using LINQ to Entities a query like this is easy to construct:[TestMethod] public void QueryLocationsTest() { var sourcePoint = CreatePoint(45.712113, -121.527200); var context = new GeoLocationContext(); // find any locations within 5 kilometers ordered by distance var matches = context.Locations .Where(loc => loc.Location.Distance(sourcePoint) < 5000) .OrderBy( loc=> loc.Location.Distance(sourcePoint) ) .Select( loc=> new { Address = loc.Address, Distance = loc.Location.Distance(sourcePoint) }); Assert.IsTrue(matches.Count() > 0); foreach (var location in matches) { Console.WriteLine("{0} ({1:n0} meters)", location.Address, location.Distance); } } This example produces: 301 15th Street, Hood River (0 meters)The Hatchery, Bingen (809 meters)Kaze Sushi, Hood River (1,074 meters)   The first point in the database is the same as my source point I'm comparing against so the distance is 0. The other two are within the 5 mile radius, while the Arlington location which is 65 miles or so out is not returned. The result is ordered by distance from closest to furthest away. In the code, I first create a source point that is the basis for comparison. The LINQ query then selects all locations that are within 5km of the source point using the Location.Distance() function, which takes a source point as a parameter. You can either use a pre-defined value as I'm doing here, or compare against another database DbGeography property (say when you have to points in the same database for things like routes). What's nice about this query syntax is that it's very clean and easy to read and understand. You can calculate the distance and also easily order by the distance to provide a result that shows locations from closest to furthest away which is a common scenario for any application that places a user in the context of several locations. It's now super easy to accomplish this. Meters vs. Miles As with the SQL Server functions, the Distance() method returns data in meters, so if you need to work with miles or feet you need to do some conversion. Here are a couple of helpers that might be useful (can be found in GeoUtils.cs of the sample project):/// <summary> /// Convert meters to miles /// </summary> /// <param name="meters"></param> /// <returns></returns> public static double MetersToMiles(double? meters) { if (meters == null) return 0F; return meters.Value * 0.000621371192; } /// <summary> /// Convert miles to meters /// </summary> /// <param name="miles"></param> /// <returns></returns> public static double MilesToMeters(double? miles) { if (miles == null) return 0; return miles.Value * 1609.344; } Using these two helpers you can query on miles like this:[TestMethod] public void QueryLocationsMilesTest() { var sourcePoint = CreatePoint(45.712113, -121.527200); var context = new GeoLocationContext(); // find any locations within 5 miles ordered by distance var fiveMiles = GeoUtils.MilesToMeters(5); var matches = context.Locations .Where(loc => loc.Location.Distance(sourcePoint) <= fiveMiles) .OrderBy(loc => loc.Location.Distance(sourcePoint)) .Select(loc => new { Address = loc.Address, Distance = loc.Location.Distance(sourcePoint) }); Assert.IsTrue(matches.Count() > 0); foreach (var location in matches) { Console.WriteLine("{0} ({1:n1} miles)", location.Address, GeoUtils.MetersToMiles(location.Distance)); } } which produces: 301 15th Street, Hood River (0.0 miles)The Hatchery, Bingen (0.5 miles)Kaze Sushi, Hood River (0.7 miles) Nice 'n simple. .NET 4.5 Only Note that DbGeography and DbGeometry are exclusive to Entity Framework 5.0 (not 4.4 which ships in the same NuGet package or installer) and requires .NET 4.5. That's because the new DbGeometry and DbGeography (and related) types are defined in the 4.5 version of System.Data.Entity which is a CLR assembly and is only updated by major versions of .NET. Why this decision was made to add these types to System.Data.Entity rather than to the frequently updated EntityFramework assembly that would have possibly made this work in .NET 4.0 is beyond me, especially given that there are no native .NET framework spatial types to begin with. I find it also odd that there is no native CLR spatial type. The DbGeography and DbGeometry types are specific to Entity Framework and live on those assemblies. They will also work for general purpose, non-database spatial data manipulation, but then you are forced into having a dependency on System.Data.Entity, which seems a bit silly. There's also a System.Spatial assembly that's apparently part of WCF Data Services which in turn don't work with Entity framework. Another example of multiple teams at Microsoft not communicating and implementing the same functionality (differently) in several different places. Perplexed as a I may be, for EF specific code the Entity framework specific types are easy to use and work well. Working with pre-.NET 4.5 Entity Framework and Spatial Data If you can't go to .NET 4.5 just yet you can also still use spatial features in Entity Framework, but it's a lot more work as you can't use the DbContext directly to manipulate the location data. You can still run raw SQL statements to write data into the database and retrieve results using the same TSQL syntax I showed earlier using Context.Database.ExecuteSqlCommand(). Here's code that you can use to add location data into the database:[TestMethod] public void RawSqlEfAddTest() { string sqlFormat = @"insert into GeoLocations( Location, Address) values ( geography::STGeomFromText('POINT({0} {1})', 4326),@p0 )"; var sql = string.Format(sqlFormat,-121.527200, 45.712113); Console.WriteLine(sql); var context = new GeoLocationContext(); Assert.IsTrue(context.Database.ExecuteSqlCommand(sql,"301 N. 15th Street") > 0); } Here I'm using the STGeomFromText() function to add the location data. Note that I'm using string.Format here, which usually would be a bad practice but is required here. I was unable to use ExecuteSqlCommand() and its named parameter syntax as the longitude and latitude parameters are embedded into a string. Rest assured it's required as the following does not work:string sqlFormat = @"insert into GeoLocations( Location, Address) values ( geography::STGeomFromText('POINT(@p0 @p1)', 4326),@p2 )";context.Database.ExecuteSqlCommand(sql, -121.527200, 45.712113, "301 N. 15th Street") Explicitly assigning the point value with string.format works however. There are a number of ways to query location data. You can't get the location data directly, but you can retrieve the point string (which can then be parsed to get Latitude and Longitude) and you can return calculated values like distance. Here's an example of how to retrieve some geo data into a resultset using EF's and SqlQuery method:[TestMethod] public void RawSqlEfQueryTest() { var sqlFormat = @" DECLARE @s geography SET @s = geography:: STGeomFromText('POINT({0} {1})' , 4326); SELECT Address, Location.ToString() as GeoString, @s.STDistance( Location) as Distance FROM GeoLocations ORDER BY Distance"; var sql = string.Format(sqlFormat, -121.527200, 45.712113); var context = new GeoLocationContext(); var locations = context.Database.SqlQuery<ResultData>(sql); Assert.IsTrue(locations.Count() > 0); foreach (var location in locations) { Console.WriteLine(location.Address + " " + location.GeoString + " " + location.Distance); } } public class ResultData { public string GeoString { get; set; } public double Distance { get; set; } public string Address { get; set; } } Hopefully you don't have to resort to this approach as it's fairly limited. Using the new DbGeography/DbGeometry types makes this sort of thing so much easier. When I had to use code like this before I typically ended up retrieving data pks only and then running another query with just the PKs to retrieve the actual underlying DbContext entities. This was very inefficient and tedious but it did work. Summary For the current project I'm working on we actually made the switch to .NET 4.5 purely for the spatial features in EF 5.0. This app heavily relies on spatial queries and it was worth taking a chance with pre-release code to get this ease of integration as opposed to manually falling back to stored procedures or raw SQL string queries to return spatial specific queries. Using native Entity Framework code makes life a lot easier than the alternatives. It might be a late addition to Entity Framework, but it sure makes location calculations and storage easy. Where do you want to go today? ;-) Resources Download Sample Project© Rick Strahl, West Wind Technologies, 2005-2012Posted in ADO.NET  Sql Server  .NET   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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  • SQL SERVER – Implementing IF … THEN in SQL SERVER with CASE Statements

    - by Pinal Dave
    Here is the question I received the other day in email. “I have business logic in my .net code and we use lots of IF … ELSE logic in our code. I want to move the logic to Stored Procedure. How do I convert the logic of the IF…ELSE to T-SQL. Please help.” I have previously received this answer few times. As data grows the performance problems grows more as well. Here is the how you can convert the logic of IF…ELSE in to CASE statement of SQL Server. Here are few of the examples: Example 1: If you are logic is as following: IF -1 < 1 THEN ‘TRUE’ ELSE ‘FALSE’ You can just use CASE statement as follows: -- SQL Server 2008 and earlier version solution SELECT CASE WHEN -1 < 1 THEN 'TRUE' ELSE 'FALSE' END AS Result GO -- SQL Server 2012 solution SELECT IIF ( -1 < 1, 'TRUE', 'FALSE' ) AS Result; GO If you are interested further about how IIF of SQL Server 2012 works read the blog post which I have written earlier this year . Well, in our example the condition which we have used is pretty simple but in the real world the logic can very complex. Let us see two different methods of how we an do CASE statement when we have logic based on the column of the table. Example 2: If you are logic is as following: IF BusinessEntityID < 10 THEN FirstName ELSE IF BusinessEntityID > 10 THEN PersonType FROM Person.Person p You can convert the same in the T-SQL as follows: SELECT CASE WHEN BusinessEntityID < 10 THEN FirstName WHEN BusinessEntityID > 10 THEN PersonType END AS Col, BusinessEntityID, Title, PersonType FROM Person.Person p However, if your logic is based on multiple column and conditions are complicated, you can follow the example 3. Example 3: If you are logic is as following: IF BusinessEntityID < 10 THEN FirstName ELSE IF BusinessEntityID > 10 AND Title IS NOT NULL THEN PersonType ELSE IF Title = 'Mr.' THEN 'Mister' ELSE 'No Idea' FROM Person.Person p You can convert the same in the T-SQL as follows: SELECT CASE WHEN BusinessEntityID < 10 THEN FirstName WHEN BusinessEntityID > 10 AND Title IS NOT NULL THEN PersonType WHEN Title = 'Mr.' THEN 'Mister' ELSE 'No Idea' END AS Col, BusinessEntityID, Title, PersonType FROM Person.Person p I hope this solution is good enough to convert the IF…ELSE logic to CASE Statement in SQL Server. Let me know if you need further information about the same. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Function, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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  • Introducing AutoVue Document Print Service

    - by celine.beck
    We recently announced the availability of our new AutoVue Document Print Service products. For more information, please read the article entitled Print Any Document Type with AutoVue Document Print Services that was posted on our blog. The AutoVue Document Print Service products help address a trivial, yet very common challenge: printing and batch printing documents. The AutoVue Document Print Service is a Web-Services based interface, which allows developers to complement their print server solutions by leveraging AutoVue's printing capabilities within broader enterprise applications like Asset Lifecycle Management, Product Lifecycle Management, Enterprise Content Management solutions, etc. This means that you can leverage the AutoVue Document Print Service products as part of your printing solution to automate the printing of virtually any document type required in any business process. Clients that consume AutoVue's Document Print Service can be written in any language (for example Java or .NET) as long as they understand Web Services Description Language (WSDL) and communicate using Simple Object Access Protocol (SOAP). The print solution consists of three main components, as described in the diagram below: a print server (not included in the AutoVue Document Print Service offering) that will interact with your application to identify the files that need to be printed, the printer to send each file, as well as the print options needed for each file (paper size, page orientation, etc), and collate the print job requests. The print server will also take care of calling the AutoVue Document Print Service to perform the actual printing. The AutoVue Document Print Services send files to a printer for printing. The AutoVue Document Print Service products leverage AutoVue's format- and platform agnostic technology to let you print/batch virtually any type of files, without requiring the authoring application installed on your machine. and Printers As shown above, you can trigger printing from your application either programmatically through automated business processes or manually through human interaction. If documents that need to be printed from your application are stored inside a content repository/Document Management System (DMS) such as Oracle Universal Content Management System (UCM), then the Print Server will need to identify the list of documents and pass the ID of each document to the AutoVue DPS to print. In this case, AutoVue DPS leverages the AutoVue VueLink integration (note: AutoVue VueLink integrations are pre-packaged AutoVue integrations with most common enterprise systems. Check our Website for more information on the subject) to fetch documents out of the document management system for printing. In lieu of the AutoVue VueLink integration, you can also leverage the AutoVue Integration Software Development Kit (iSDK) to build your own connector. If the documents you need to print from your application are not stored in a content management system, the Print Server will need to ensure that files are made available to the AutoVue Document Print Service. The Print Server could for example fetch the files out of your application or an extension to the application could be developed to fetch the files and make them available to the AutoVue DPS. More information on methods to pass on file information to the AutoVue Document Print Service products can be found in the AutoVue Document Print Service Overview documentation available on the Oracle Technology Network. Related article: Any Document Type with AutoVue Document Print Services

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  • The embarrassingly obvious about SQL Server CE

    - by Edward Boyle
    I have been working with SQL servers in one form or another for almost two decades now. But I am new to SQL Server Compact Edition. In the past weeks I have been working with SQL Serve CE a lot. The SQL, not a problem, but the engine itself is very new to me. One of the issues I ran into was a simple SQL statement taking excusive amounts of time; by excessive, I mean over one second. I wrote a little code to time the method. Sometimes it took under one second, other times as long as three seconds. –But it was a simple update statement! As embarrassing as it is, why it was slow eluded me. I posted my issue to MSDN and I got a reply from ErikEJ (MS MVP) who runs the blog “Everything SQL Server Compact” . I know little to nothing about SQL Server Compact. This guy is completely obsessed very well versed in CE. If you spend any time in MSDN forums, it seems that this guy single handedly has the answer for every CE question that comes up. Anyway, he said: “Opening a connection to a SQL Server Compact database file is a costly operation, keep one connection open per thread (incl. your UI thread) in your app, the one on the UI thread should live for the duration of your app.” It hit me, all databases have some connection overhead and SQL Server CE is not a database engine running as a service drinking Jolt Cola waiting for someone to talk to him so he can spring into action and show off his quarter-mile sprint capabilities. Imagine if you had to start the SQL Server process every time you needed to make a database connection. Principally, that is what you are doing with SQL Server CE. For someone who has worked with Enterprise Level SQL Servers a lot, I had to come to the mental image that my Open connection to SQL Server CE is basically starting a service, my own private service, and by closing the connection, I am shutting down my little private service. After making the changes in my code, I lost any reservations I had with using CE. At present, my Data Access Layer class has a constructor; in that constructor I open my connection, I also have OpenConnection and CloseConnection methods, I also implemented IDisposable and clean up any connections in Dispose(). I am still finalizing how this assembly will function. – That’s beside the point. All I’m trying to say is: “Opening a connection to a SQL Server Compact database file is a costly operation”

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  • DevConnections jQuery Session Slides and Samples posted

    - by Rick Strahl
    I’ve posted all of my slides and samples from the DevConnections VS 2010 Launch event last week in Vegas. All three sessions are contained in a single zip file which contains all slide decks and samples in one place: www.west-wind.com/files/conferences/jquery.zip There were 3 separate sessions: Using jQuery with ASP.NET Starting with an overview of jQuery client features via many short and fun examples, you'll find out about core features like the power of selectors to select document elements, manipulate these elements with jQuery's wrapped set methods in a browser independent way, how to hook up and handle events easily and generally apply concepts of unobtrusive JavaScript principles to client scripting. The session also covers AJAX interaction between jQuery and the .NET server side code using several different approaches including sending HTML and JSON data and how to avoid user interface duplication by using client side templating. This session relies heavily on live examples and walk-throughs. jQuery Extensibility and Integration with ASP.NET Server Controls One of the great strengths of the jQuery Javascript framework is its simple, yet powerful extensibility model that has resulted in an explosion of plug-ins available for jQuery. You need it - chances are there's a plug-in for it! In this session we'll look at a few plug-ins to demonstrate the power of the jQuery plug-in model before diving in and creating our own custom jQuery plug-ins. We'll look at how to create a plug-in from scratch as well as discussing when it makes sense to do so. Once you have a plug-in it can also be useful to integrate it more seamlessly with ASP.NET by creating server controls that coordinate both server side and jQuery client side behavior. I'll demonstrate a host of custom components that utilize a combination of client side jQuery functionality and server side ASP.NET server controls that provide smooth integration in the user interface development process. This topic focuses on component development both for pure client side plug-ins and mixed mode controls. jQuery Tips and Tricks This session was kind of a last minute substitution for an ASP.NET AJAX talk. Nothing too radical here :-), but I focused on things that have been most productive for myself. Look at the slide deck for individual points and some of the specific samples.   It was interesting to see that unlike in previous conferences this time around all the session were fairly packed – interest in jQuery is definitely getting more pronounced especially with microsoft’s recent announcement of focusing on jQuery integration rather than continuing on the path of ASP.NET AJAX – which is a welcome change. Most of the samples also use the West Wind Web & Ajax Toolkit and the support tools contained within it – a snapshot version of the toolkit is included in the samples download. Specicifically a number of the samples use functionality in the ww.jquery.js support file which contains a fairly large set of plug-ins and helper functionality – most of these pieces while contained in the single file are self-contained and can be lifted out of this file (several people asked). Hopefully you'll find something useful in these slides and samples.© Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET  jQuery  

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  • SQL SERVER – Dedicated Access Control for SQL Server Express Edition – An error occurred while obtaining the dedicated administrator connection (DAC) port.

    - by pinaldave
    Recently I had faced very interesting situation. Due to some reason we were not able to login into the production server for one of client. The reason for the same was that server was very busy, we had to login into the system and bring server to normal situation. When all the attempts failed, I decided to login using Dedicated Administrator Connection (DAC). However when I attempted to connect using DAC it threw following error for me. C:\Users\pinald>sqlcmd -A -d master -S .\SQLEXPRESS Sqlcmd: Error: Microsoft SQL Server Native Client 11.0 : SQL Server Network Interfaces: An error occurred while obtaining the dedicated administrator connection (DAC) port. Make sure that SQL Browser is running, or check the error log for t he port number [xFFFFFFFF]. .Sqlcmd: Error: Microsoft SQL Server Native Client 11.0 : Login timeout expired.Sqlcmd: Error: Microsoft SQL Server Native Client 11.0 : A network-related or instance-specific error has occurred while establishing a connection to SQL Server. Server is not found or not accessible. Check if instance name is correct and if SQL Server is configured to allow remote connections. For more information see SQL Server Books Online. I was bit taken a back as I knew that my commands are correct to login and if DAC does not work, there should be some serious reason for it. When inquired further about the SQL Server version I learned that it was SQL Server Express version deployed. To conserve resources, SQL Server Express does not listen on the DAC port. There is an additional step to be done if SQL Server Express has to be used with DAC. Enable TRACEFLAG on SQL Server Express will enable the connection by DAC possible. Here is the quick methods how one can enable DAC on SQL Server Express. Go to Start >> All Program >>Microsoft SQL Server (your version) >> Configuration Tools >> SQL Server Configuration Manager. Click on SQL Server Services >> Select your SQL Server Express version >> Right Click Properties >> select Startup Parameters Once on the Startup Parameter add the Startup parameter which is TRACEFLAG -T7806. Click on OK and RESTART SQL Server Express edition. Now once again try to connect to SQL Server Express edition and it will work just fine. This is absolutely documented method on BOL and SQL Server Express needs to be restarted. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Error Messages, SQL Interview Questions and Answers, SQL Query, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology Tagged: SQL Server Express

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  • Should I implement BackBone.js into my ASP.NET WebForms applications?

    - by Walter Stabosz
    Background I'm trying to improve my group's current web app development pattern. Our current pattern is something we came up with while trying to rich web apps on top of ASP.NET WebForms (none of us knew ASP.NET MVC). This is the current pattern: ! Our application is using the WinForms Framework. Our ASPX pages are essentially just HTML, we use almost no WebControls. We use JavaScript/jQuery to perform all of our UI events and AJAX calls. For a single ASPX page, we have a single .js file. All of our AJAX calls are POSTs (not RESTful at all) Our AJAX calls contact WebMethods which we have defined in a series of ASMX files. One ASMX file per business object. Why Change? I want to revise our pattern a bit for a couple of reasons: We're starting to find that our JavaScript files are getting a bit unwieldy. We're using a hodgepodge of methods for keeping our local data and DOM updates in sync. We seem to spend too much time writing code to keep things in sync, and it can get tricky to debug. I've been reading Developing Backbone.js Applications and I like a lot of what Backbone has to offer in terms of code organization and separation of concerns. However, I've gotten to the chapter on RESTful app, I started to feel some hesitation about using Backbone. The Problem The problem is our WebMethods do not really fit into the RESTful pattern, which seems to be the way Backbone wants to consume them. For now, I'd only like to address our issue of disorganized client side code. I'd like to avoid major rewrites to our WebMethods. My Questions Is it possible to use Backbone (or a similar library) to clean up our client code, while not majorly impacting our data access WebMethods? Or would trying to use Backbone in this manner be a bastardization of it's intended use? Anyone have any suggestions for improving our pattern in the area of code organization and spending less time writing DOM and data sync code?

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  • Windows Azure Use Case: Fast Acquisitions

    - by BuckWoody
    This is one in a series of posts on when and where to use a distributed architecture design in your organization's computing needs. You can find the main post here: http://blogs.msdn.com/b/buckwoody/archive/2011/01/18/windows-azure-and-sql-azure-use-cases.aspx  Description: Many organizations absorb, take over or merge with other organizations. In these cases, one of the most difficult parts of the process is the merging or changing of the IT systems that the employees use to do their work, process payments, and even get paid. Normally this means that the two companies have disparate systems, and several approaches can be used to have the two organizations use technology between them. An organization may choose to retain both systems, and manage them separately. The advantage here is speed, and keeping the profit/loss sheets separate. Another choice is to slowly “sunset” or stop using one organization’s system, and cutting to the other system immediately or at a later date. Although a popular choice, one of the most difficult methods is to extract data and processes from one system and import it into the other. Employees at the transitioning system have to be trained on the new one, the data must be examined and cleansed, and there is inevitable disruption when this happens. Still another option is to integrate the systems. This may prove to be as much work as a transitional strategy, but may have less impact on the users or the balance sheet. Implementation: A distributed computing paradigm can be a good strategic solution to most of these strategies. Retaining both systems is made more simple by allowing the users at the second organization immediate access to the new system, because security accounts can be created quickly inside an application. There is no need to set up a VPN or any other connections than just to the Internet. Having the users stop using one system and start with the other is also simple in Windows Azure for the same reason. Extracting data to Azure holds the same limitations as an on-premise system, and may even be more problematic because of the large data transfers that might be required. In a distributed environment, you pay for the data transfer, so a mixed migration strategy is not recommended. However, if the data is slowly migrated over time with a defined cutover, this can be an effective strategy. If done properly, an integration strategy works very well for a distributed computing environment like Windows Azure. If the Azure code is architected as a series of services, then endpoints can expose the service into and out of not only the Azure platform, but internally as well. This is a form of the Hybrid Application use-case documented here. References: Designing for Cloud Optimized Architecture: http://blogs.msdn.com/b/dachou/archive/2011/01/23/designing-for-cloud-optimized-architecture.aspx 5 Enterprise steps for adopting a Platform as a Service: http://blogs.msdn.com/b/davidmcg/archive/2010/12/02/5-enterprise-steps-for-adopting-a-platform-as-a-service.aspx?wa=wsignin1.0

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  • Silverlight Cream for April 04, 2010 -- #830

    - by Dave Campbell
    In this Issue: Michael Washington, Hassan, David Anson, Jeff Wilcox, UK Application Development Consulting, Davide Zordan, Victor Gaudioso, Anoop Madhusudanan, Phil Middlemiss, and Laurent Bugnion. Shoutouts: Josh Smith has a good-read post up: Design-time data is still data Shawn Hargreaves reported his MIX demo released From SilverlightCream.com: Silverlight MVVM: Enabling Design-Time Data in Expression Blend When Using Web Services Michael Washington has a tutorial up on MVVM and using a web service to get design-time data that works in Blend also... lots of information and screenshots. WP7 Transition Animation Hassan has a new WP7 tutorial up that demonstrates playing media and adding transition animation between pages. Tip: For a truly read-only custom DependencyProperty in Silverlight, use a read-only CLR property instead David Anson's latest tip is in response to comments on his previous post and details one by Dr. WPF who points out that a read-only DependencyProperty doesn't actually need to be a DependencyProperty as long as the class implements INotifyPropertyChanged. Template parts and custom controls (quick tip) Jeff Wilcox has posted a set of tips and recommendations to use when developing control development in Silverlight ... this is a post to bookmark. Flexible Data Template Support in Silverlight The UK Application Development Consulting details a 'problem' in Silverlight that doesn't exist in WPF and that is data templates that vary by type... and discusses a way around it. Multi-Touch enabling Silverlight Simon using Blend behaviors and the Surface sample for Silverlight Davide Zordan brought Multi-Touch to the Silverlight Simon game on CodePlex using Blend Behaviors. New Video Tutorial: How to Use a Behavior to Fire Methods from Objects in Styles Victor Gaudioso has a video tutorial up responding to a question from a developer. He demonstrates development of a Behavior that can be attached to objects in or out of Styles that allows you to specify what Method they need to fire. Creating a Silverlight Client for @shanselman ’s Nerd Dinner, using oData and Bing Maps Anoop Madhusudanan took Scott Hanselman's post on an OData API for StackOverflow, and has created a Silverlight client for Nerd Dinner, including BingMaps. A Chrome and Glass Theme - Part 2 Phil Middlemiss has the next part of his Chrome and Glass Theme up. In this one he creates a very nice chrome-look button with visual state changes. MVVM Light Toolkit V3 SP1 for Windows Phone 7 Laurent Bugnion has released a new version of MVVM Light for WP7. Included is an installation manual and information about what was changed. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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  • MVC Architecture

    Model-View-Controller (MVC) is an architectural design pattern first written about and implemented by  in 1978. Trygve developed this pattern during the year he spent working with Xerox PARC on a small talk application. According to Trygve, “The essential purpose of MVC is to bridge the gap between the human user's mental model and the digital model that exists in the computer. The ideal MVC solution supports the user illusion of seeing and manipulating the domain information directly. The structure is useful if the user needs to see the same model element simultaneously in different contexts and/or from different viewpoints.”  Trygve Reenskaug on MVC The MVC pattern is composed of 3 core components. Model View Controller The Model component referenced in the MVC pattern pertains to the encapsulation of core application data and functionality. The primary goal of the model is to maintain its independence from the View and Controller components which together form the user interface of the application. The View component retrieves data from the Model and displays it to the user. The View component represents the output of the application to the user. Traditionally the View has read-only access to the Model component because it should not change the Model’s data. The Controller component receives and translates input to requests on the Model or View components. The Controller is responsible for requesting methods on the model that can change the state of the model. The primary benefit to using MVC as an architectural pattern in a project compared to other patterns is flexibility. The flexibility of MVC is due to the distinct separation of concerns it establishes with three distinct components.  Because of the distinct separation between the components interaction is limited through the use of interfaces instead of classes. This allows each of the components to be hot swappable when the needs of the application change or needs of availability change. MVC can easily be applied to C# and the .Net Framework. In fact, Microsoft created a MVC project template that will allow new project of this type to be created with the standard MVC structure in place before any coding begins. The project also creates folders for the three key components along with default Model, View and Controller classed added to the project. Personally I think that MVC is a great pattern in regards to dealing with web applications because they could be viewed from a myriad of devices. Examples of devices include: standard web browsers, text only web browsers, mobile phones, smart phones, IPads, IPhones just to get started. Due to the potentially increasing accessibility needs and the ability for components to be hot swappable is a perfect fit because the core functionality of the application can be retained and the View component can be altered based on the client’s environment and the View component could be swapped out based on the calling device so that the display is targeted to that specific device.

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  • links for 2010-04-27

    - by Bob Rhubart
    @oracletechnet: Oracle Technology Network Newsletters Revisited "You may find this hard to believe, but some analysts contend that email newsletters are still among the most preferred methods of "information awareness" by developers today. And in our experience, the numbers back it up: subscriptions to Oracle Technology Network newsletters grow organically by 15% every year, even after you take continual list cleanup into account. " -- Justin Kestelyn (tags: oracle otn newsletters developers architects) Sylvain Duloutre: Directory Services as a Web Service Sylvain Duloutre shares a WSDL file he created to deal with issues involved in XML binding generation. (tags: oracle sun wsdl webservices DSEE netbeans jdeveloper) Nick Wooler: Iron-Clad Cloud: Secure Cloud Computing "One solution to the security problem with cloud services can be overcome using Service Oriented Security. The Oracle approach to using Service Oriented Security allows developers to pull from a centralized, authoritative source of identity services. This allows developers to build security into every application from the inside-out. This is critical to ensuring this is done in a standardized manner and most importantly it allows developers to develop without being security experts." -- Nick Wooler (tags: oracle sun security cloud saas) Andy Mulholland: A week of visits; Cisco, HP, Oracle, SAP and VMware (in alphabetical order!) "I now am considering that we should be thinking about ‘clouds’ in virtual way, by which I mean that a succession of virtual ‘clouds’ will need to exist, each possessing specific characteristics that suit certain types of services. Really it’s no different to what we see with servers today. Adding a hypervisor to a server adds new flexibility, but creating a virtualised environment means much more. What I suspect will happen is that we will start to use vendor specific approaches to building what I will term a physical cloud solution using their technology and approach to supporting a specific objective, but with time we will find these physical clouds will interoperate as a fully virtualised cloud environment." -- Andy Mulholland (tags: entarch enterprisearchitecture cloudcomputing virtualization) @fteter: Highlights From The Bright Lights - Tuesday #c10 Oracle Ace Director Floyd Teter of JPL with one last wrap-up of Collaborate 10. (tags: oracle otn collaborate2010 las vegas) Rittman Mead India – Call for very good Oracle BI Developers/Architects "Now that we have an office in India and if you are interested in joining us, do drop us a line at [email protected], and we will be glad to have technical discussions with you. If you are also an Oracle BI, DW or EPM customer looking for help on projects in the Asia-Pacific region, again we’ll be pleased to hear from you and to let you know how we can help." -- Venkatakrishnan J (tags: otn oracle jobs india developers architects software)

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  • Currency Conversion in Oracle BI applications

    - by Saurabh Verma
    Authored by Vijay Aggarwal and Hichem Sellami A typical data warehouse contains Star and/or Snowflake schema, made up of Dimensions and Facts. The facts store various numerical information including amounts. Example; Order Amount, Invoice Amount etc. With the true global nature of business now-a-days, the end-users want to view the reports in their own currency or in global/common currency as defined by their business. This presents a unique opportunity in BI to provide the amounts in converted rates either by pre-storing or by doing on-the-fly conversions while displaying the reports to the users. Source Systems OBIA caters to various source systems like EBS, PSFT, Sebl, JDE, Fusion etc. Each source has its own unique and intricate ways of defining and storing currency data, doing currency conversions and presenting to the OLTP users. For example; EBS stores conversion rates between currencies which can be classified by conversion rates, like Corporate rate, Spot rate, Period rate etc. Siebel stores exchange rates by conversion rates like Daily. EBS/Fusion stores the conversion rates for each day, where as PSFT/Siebel store for a range of days. PSFT has Rate Multiplication Factor and Rate Division Factor and we need to calculate the Rate based on them, where as other Source systems store the Currency Exchange Rate directly. OBIA Design The data consolidation from various disparate source systems, poses the challenge to conform various currencies, rate types, exchange rates etc., and designing the best way to present the amounts to the users without affecting the performance. When consolidating the data for reporting in OBIA, we have designed the mechanisms in the Common Dimension, to allow users to report based on their required currencies. OBIA Facts store amounts in various currencies: Document Currency: This is the currency of the actual transaction. For a multinational company, this can be in various currencies. Local Currency: This is the base currency in which the accounting entries are recorded by the business. This is generally defined in the Ledger of the company. Global Currencies: OBIA provides five Global Currencies. Three are used across all modules. The last two are for CRM only. A Global currency is very useful when creating reports where the data is viewed enterprise-wide. Example; a US based multinational would want to see the reports in USD. The company will choose USD as one of the global currencies. OBIA allows users to define up-to five global currencies during the initial implementation. The term Currency Preference is used to designate the set of values: Document Currency, Local Currency, Global Currency 1, Global Currency 2, Global Currency 3; which are shared among all modules. There are four more currency preferences, specific to certain modules: Global Currency 4 (aka CRM Currency) and Global Currency 5 which are used in CRM; and Project Currency and Contract Currency, used in Project Analytics. When choosing Local Currency for Currency preference, the data will show in the currency of the Ledger (or Business Unit) in the prompt. So it is important to select one Ledger or Business Unit when viewing data in Local Currency. More on this can be found in the section: Toggling Currency Preferences in the Dashboard. Design Logic When extracting the fact data, the OOTB mappings extract and load the document amount, and the local amount in target tables. It also loads the exchange rates required to convert the document amount into the corresponding global amounts. If the source system only provides the document amount in the transaction, the extract mapping does a lookup to get the Local currency code, and the Local exchange rate. The Load mapping then uses the local currency code and rate to derive the local amount. The load mapping also fetches the Global Currencies and looks up the corresponding exchange rates. The lookup of exchange rates is done via the Exchange Rate Dimension provided as a Common/Conforming Dimension in OBIA. The Exchange Rate Dimension stores the exchange rates between various currencies for a date range and Rate Type. Two physical tables W_EXCH_RATE_G and W_GLOBAL_EXCH_RATE_G are used to provide the lookups and conversions between currencies. The data is loaded from the source system’s Ledger tables. W_EXCH_RATE_G stores the exchange rates between currencies with a date range. On the other hand, W_GLOBAL_EXCH_RATE_G stores the currency conversions between the document currency and the pre-defined five Global Currencies for each day. Based on the requirements, the fact mappings can decide and use one or both tables to do the conversion. Currency design in OBIA also taps into the MLS and Domain architecture, thus allowing the users to map the currencies to a universal Domain during the implementation time. This is especially important for companies deploying and using OBIA with multiple source adapters. Some Gotchas to Look for It is necessary to think through the currencies during the initial implementation. 1) Identify various types of currencies that are used by your business. Understand what will be your Local (or Base) and Documentation currency. Identify various global currencies that your users will want to look at the reports. This will be based on the global nature of your business. Changes to these currencies later in the project, while permitted, but may cause Full data loads and hence lost time. 2) If the user has a multi source system make sure that the Global Currencies and Global Rate Types chosen in Configuration Manager do have the corresponding source specific counterparts. In other words, make sure for every DW specific value chosen for Currency Code or Rate Type, there is a source Domain mapping already done. Technical Section This section will briefly mention the technical scenarios employed in the OBIA adaptors to extract data from each source system. In OBIA, we have two main tables which store the Currency Rate information as explained in previous sections. W_EXCH_RATE_G and W_GLOBAL_EXCH_RATE_G are the two tables. W_EXCH_RATE_G stores all the Currency Conversions present in the source system. It captures data for a Date Range. W_GLOBAL_EXCH_RATE_G has Global Currency Conversions stored at a Daily level. However the challenge here is to store all the 5 Global Currency Exchange Rates in a single record for each From Currency. Let’s voyage further into the Source System Extraction logic for each of these tables and understand the flow briefly. EBS: In EBS, we have Currency Data stored in GL_DAILY_RATES table. As the name indicates GL_DAILY_RATES EBS table has data at a daily level. However in our warehouse we store the data with a Date Range and insert a new range record only when the Exchange Rate changes for a particular From Currency, To Currency and Rate Type. Below are the main logical steps that we employ in this process. (Incremental Flow only) – Cleanup the data in W_EXCH_RATE_G. Delete the records which have Start Date > minimum conversion date Update the End Date of the existing records. Compress the daily data from GL_DAILY_RATES table into Range Records. Incremental map uses $$XRATE_UPD_NUM_DAY as an extra parameter. Generate Previous Rate, Previous Date and Next Date for each of the Daily record from the OLTP. Filter out the records which have Conversion Rate same as Previous Rates or if the Conversion Date lies within a single day range. Mark the records as ‘Keep’ and ‘Filter’ and also get the final End Date for the single Range record (Unique Combination of From Date, To Date, Rate and Conversion Date). Filter the records marked as ‘Filter’ in the INFA map. The above steps will load W_EXCH_RATE_GS. Step 0 updates/deletes W_EXCH_RATE_G directly. SIL map will then insert/update the GS data into W_EXCH_RATE_G. These steps convert the daily records in GL_DAILY_RATES to Range records in W_EXCH_RATE_G. We do not need such special logic for loading W_GLOBAL_EXCH_RATE_G. This is a table where we store data at a Daily Granular Level. However we need to pivot the data because the data present in multiple rows in source tables needs to be stored in different columns of the same row in DW. We use GROUP BY and CASE logic to achieve this. Fusion: Fusion has extraction logic very similar to EBS. The only difference is that the Cleanup logic that was mentioned in step 0 above does not use $$XRATE_UPD_NUM_DAY parameter. In Fusion we bring all the Exchange Rates in Incremental as well and do the cleanup. The SIL then takes care of Insert/Updates accordingly. PeopleSoft:PeopleSoft does not have From Date and To Date explicitly in the Source tables. Let’s look at an example. Please note that this is achieved from PS1 onwards only. 1 Jan 2010 – USD to INR – 45 31 Jan 2010 – USD to INR – 46 PSFT stores records in above fashion. This means that Exchange Rate of 45 for USD to INR is applicable for 1 Jan 2010 to 30 Jan 2010. We need to store data in this fashion in DW. Also PSFT has Exchange Rate stored as RATE_MULT and RATE_DIV. We need to do a RATE_MULT/RATE_DIV to get the correct Exchange Rate. We generate From Date and To Date while extracting data from source and this has certain assumptions: If a record gets updated/inserted in the source, it will be extracted in incremental. Also if this updated/inserted record is between other dates, then we also extract the preceding and succeeding records (based on dates) of this record. This is required because we need to generate a range record and we have 3 records whose ranges have changed. Taking the same example as above, if there is a new record which gets inserted on 15 Jan 2010; the new ranges are 1 Jan to 14 Jan, 15 Jan to 30 Jan and 31 Jan to Next available date. Even though 1 Jan record and 31 Jan have not changed, we will still extract them because the range is affected. Similar logic is used for Global Exchange Rate Extraction. We create the Range records and get it into a Temporary table. Then we join to Day Dimension, create individual records and pivot the data to get the 5 Global Exchange Rates for each From Currency, Date and Rate Type. Siebel: Siebel Facts are dependent on Global Exchange Rates heavily and almost none of them really use individual Exchange Rates. In other words, W_GLOBAL_EXCH_RATE_G is the main table used in Siebel from PS1 release onwards. As of January 2002, the Euro Triangulation method for converting between currencies belonging to EMU members is not needed for present and future currency exchanges. However, the method is still available in Siebel applications, as are the old currencies, so that historical data can be maintained accurately. The following description applies only to historical data needing conversion prior to the 2002 switch to the Euro for the EMU member countries. If a country is a member of the European Monetary Union (EMU), you should convert its currency to other currencies through the Euro. This is called triangulation, and it is used whenever either currency being converted has EMU Triangulation checked. Due to this, there are multiple extraction flows in SEBL ie. EUR to EMU, EUR to NonEMU, EUR to DMC and so on. We load W_EXCH_RATE_G through multiple flows with these data. This has been kept same as previous versions of OBIA. W_GLOBAL_EXCH_RATE_G being a new table does not have such needs. However SEBL does not have From Date and To Date columns in the Source tables similar to PSFT. We use similar extraction logic as explained in PSFT section for SEBL as well. What if all 5 Global Currencies configured are same? As mentioned in previous sections, from PS1 onwards we store Global Exchange Rates in W_GLOBAL_EXCH_RATE_G table. The extraction logic for this table involves Pivoting data from multiple rows into a single row with 5 Global Exchange Rates in 5 columns. As mentioned in previous sections, we use CASE and GROUP BY functions to achieve this. This approach poses a unique problem when all the 5 Global Currencies Chosen are same. For example – If the user configures all 5 Global Currencies as ‘USD’ then the extract logic will not be able to generate a record for From Currency=USD. This is because, not all Source Systems will have a USD->USD conversion record. We have _Generated mappings to take care of this case. We generate a record with Conversion Rate=1 for such cases. Reusable Lookups Before PS1, we had a Mapplet for Currency Conversions. In PS1, we only have reusable Lookups- LKP_W_EXCH_RATE_G and LKP_W_GLOBAL_EXCH_RATE_G. These lookups have another layer of logic so that all the lookup conditions are met when they are used in various Fact Mappings. Any user who would want to do a LKP on W_EXCH_RATE_G or W_GLOBAL_EXCH_RATE_G should and must use these Lookups. A direct join or Lookup on the tables might lead to wrong data being returned. Changing Currency preferences in the Dashboard: In the 796x series, all amount metrics in OBIA were showing the Global1 amount. The customer needed to change the metric definitions to show them in another Currency preference. Project Analytics started supporting currency preferences since 7.9.6 release though, and it published a Tech note for other module customers to add toggling between currency preferences to the solution. List of Currency Preferences Starting from 11.1.1.x release, the BI Platform added a new feature to support multiple currencies. The new session variable (PREFERRED_CURRENCY) is populated through a newly introduced currency prompt. This prompt can take its values from the xml file: userpref_currencies_OBIA.xml, which is hosted in the BI Server installation folder, under :< home>\instances\instance1\config\OracleBIPresentationServicesComponent\coreapplication_obips1\userpref_currencies.xml This file contains the list of currency preferences, like“Local Currency”, “Global Currency 1”,…which customers can also rename to give them more meaningful business names. There are two options for showing the list of currency preferences to the user in the dashboard: Static and Dynamic. In Static mode, all users will see the full list as in the user preference currencies file. In the Dynamic mode, the list shown in the currency prompt drop down is a result of a dynamic query specified in the same file. Customers can build some security into the rpd, so the list of currency preferences will be based on the user roles…BI Applications built a subject area: “Dynamic Currency Preference” to run this query, and give every user only the list of currency preferences required by his application roles. Adding Currency to an Amount Field When the user selects one of the items from the currency prompt, all the amounts in that page will show in the Currency corresponding to that preference. For example, if the user selects “Global Currency1” from the prompt, all data will be showing in Global Currency 1 as specified in the Configuration Manager. If the user select “Local Currency”, all amount fields will show in the Currency of the Business Unit selected in the BU filter of the same page. If there is no particular Business Unit selected in that filter, and the data selected by the query contains amounts in more than one currency (for example one BU has USD as a functional currency, the other has EUR as functional currency), then subtotals will not be available (cannot add USD and EUR amounts in one field), and depending on the set up (see next paragraph), the user may receive an error. There are two ways to add the Currency field to an amount metric: In the form of currency code, like USD, EUR…For this the user needs to add the field “Apps Common Currency Code” to the report. This field is in every subject area, usually under the table “Currency Tag” or “Currency Code”… In the form of currency symbol ($ for USD, € for EUR,…) For this, the user needs to format the amount metrics in the report as a currency column, by specifying the currency tag column in the Column Properties option in Column Actions drop down list. Typically this column should be the “BI Common Currency Code” available in every subject area. Select Column Properties option in the Edit list of a metric. In the Data Format tab, select Custom as Treat Number As. Enter the following syntax under Custom Number Format: [$:currencyTagColumn=Subjectarea.table.column] Where Column is the “BI Common Currency Code” defined to take the currency code value based on the currency preference chosen by the user in the Currency preference prompt.

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  • Perfect Your MySQL Database Administrators Skills

    - by Antoinette O'Sullivan
    With its proven ease-of-use, performance, and scalability, MySQL has become the leading database choice for web-based applications, used by high profile web properties including Google, Yahoo!, Facebook, YouTube, Wikipedia and thousands of mid-sized companies. Many organizations deploy both Oracle Database and MySQL side by side to serve different needs, and as a database professional you can find training courses on both topics at Oracle University! Check out the upcoming Oracle Database training courses and MySQL training courses. Even if you're only managing Oracle Databases at this point of time, getting familiar with MySQL Database will broaden your career path with growing job demand. Hone your skills as a MySQL Database Administrator by taking the MySQL for Database Administrators course which teaches you how to secure privileges, set resource limitations, access controls and describe backup and recovery basics. You also learn how to create and use stored procedures, triggers and views. You can take this 5 day course through three delivery methods: Training-on-Demand: Take this course at your own pace and at a time that suits you through this high-quality streaming video delivery. You also get to schedule time on a classroom environment to perform the hands-on exercises. Live-Virtual: Attend a live instructor led event from your own desk. 100s of events already of the calendar in many timezones. In-Class: Travel to an education center to attend this class. A sample of events is shown below:  Location  Date  Delivery Language  Budapest, Hungary  26 November 2012  Hungarian  Prague, Czech Republic  19 November 2012  Czech  Warsaw, Poland  10 December 2012  Polish  Belfast, Northern Ireland  26 November, 2012  English  London, England  26 November, 2012  English  Rome, Italy  19 November, 2012  Italian  Lisbon, Portugal  12 November, 2012  European Portugese  Porto, Portugal  21 January, 2013  European Portugese  Amsterdam, Netherlands  19 November, 2012  Dutch  Nieuwegein, Netherlands  8 April, 2013  Dutch  Barcelona, Spain  4 February, 2013  Spanish  Madrid, Spain  19 November, 2012  Spanish  Mechelen, Belgium  25 February, 2013  English  Windhof, Luxembourg  19 November, 2012  English  Johannesburg, South Africa  9 December, 2012  English  Cairo, Egypt  20 October, 2012  English  Nairobi, Kenya  26 November, 2012  English  Petaling Jaya, Malaysia  29 October, 2012  English  Auckland, New Zealand  5 November, 2012  English  Wellington, New Zealand  23 October, 2012  English  Brisbane, Australia  19 November, 2012  English  Edmonton, Canada  7 January, 2013  English  Vancouver, Canada  7 January, 2013  English  Ottawa, Canada  22 October, 2012  English  Toronto, Canada  22 October, 2012  English  Montreal, Canada  22 October, 2012  English  Mexico City, Mexico  10 December, 2012  Spanish  Sao Paulo, Brazil  10 December, 2012  Brazilian Portugese For more information on this course or any aspect of the MySQL curriculum, visit http://oracle.com/education/mysql.

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  • Getting Started With nServiceBus on VAN Mar 31

    - by van
    Topic: nServiceBus is mature and powerful open source framework that enables to design robust, scalable, message-based, service-oriented architectures. Latest improvements in the configuration API enables developers to quickly get started and build a working simple system that uses messaging infrastructure. The goal of this session is to give a jump start with the framework, introduce basic concepts such as message handlers, Sagas, Pub/Sub, Generic Host and also create a working demo application that uses publish/subscribe messaging. The content of the session is addressed to developers that are interested in learning how to get started using nServiceBus in order to design and build distributed systems. Bio: Bernard Kowalski is currently a Software Developer at Microdesk, one of Autodesk's leading partners in providing variety of Geospatial and Computer-Aided Design solutions. Bernard has experience developing .NET framework-based applications utilizing Windows Forms, Windows Services, ASP.NET MVC, and Web services. In a recent project, Bernard architected and implemented a distributed system based on SOA principles using an open source implementation of an Enterprise Service Bus. Bernard develops software with Agile patterns and practices using Domain Driven Design combined with TDD (Test Driven Development). He is familiar with all of the following APIs: Autodesk Vault/Product Stream API, AutoCAD ActiveX/VBA/.NET API, AutoCAD Mechanical API, Autodesk Inventor API, Autodesk MapGuide Enterprise. Prior to joining Microdesk, Bernard worked as a researcher and teacher at the University of Science and Technology in Krakow, Poland where he was awarded with a PhD in Computer Methods in Materials Science. He also participated in research projects where he developed applications for analysis of hot compression test results using advanced optimization techniques. He also developed Finite Element Method-based programs for thermal and stress analysis using C++ and FORTRAN. Bernard is a member of the Domain Driven Design and ALT.NET user groups in NYC. Virtual ALT.NET (VAN) is the online gathering place of the ALT.NET community. Through conversations, presentations, pair programming and dojos, we strive to improve, explore, and challenge the way we create software. Using net conferencing technology such as Skype and LiveMeeting, we hold regular meetings, open to anyone, usually taking the form of a presentation or an Open Space Technology-style conversation. Please see the Calendar(http://www.virtualaltnet.com/Home/Calendar) to find a VAN group that meets at a time convenient to you, and feel welcome to join a meeting. Past sessions can be found on the Recording page. To stay informed about VAN activities, you can subscribe to the Virtual ALT.NET Google Group and follow the Virtual ALT.NET blog. Times below are Central Standard Time Start Time: Wed, Mar 31, 2010 8:00 PM UTC/GMT -5 hours End Time: Wed, Mar 31, 2010 10:00 PM UTC/GMT -5 hours Attendee URL: http://www.virtualaltnet.com/van Zach Young http://www.virtualaltnet.com

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  • Paying by Cash

    - by David Dorf
    I'll grant you paying by cash in the context of stores isn't particularly interesting, but in my quest to try new payment methods I decided to pay by cash at an online store. Using a credit card means I have to hoist myself off the couch, find the card, and enter all those digits. Google Checkout certainly makes that task easier by storing my credit card information, but what happens to all those people that don't have a credit card? What about the ones that are afraid to use credit cards over the internet. There are three main options for cash payment, not all of which are accepted by every merchant. The most popular is PayPal. The issue I have with them is that returns and disputes have to be handled with PayPal, not the merchant. I once used PayPal at a shady online store and lost my money. Yeah, my bad but they wouldn't help me at all. PayPal was purchased by eBay in 2002. BillMeLater is best for larger purchases, because at checkout they actually run a credit check to make sure you're credit worthy. Assuming you are, they pay the merchant on your behalf and mail you a bill, which you better pay quickly or interest will start to accrue. That's nice for the merchant because they get paid right away, and I presume there's no charge-backs. BillMeLater was purchased by eBay in 2008. Last night I tried eBillMe for the first time. After checkout, they send you a bill via email and expect you to pay either via online banking (they provide the instructions to set everything up) or walk-in locations across the US (typically banks). The process was quick and easy. The merchant doesn't ship the product until the bill is paid, so there's a day or two delay. For the merchant there are no charge-backs, and the fees are less than credit cards. For the shopper, they provide buyer protection similar to that offered by credit cards, and 1% cashback on purchases. Once the online bill-pay is setup, its easy to reuse in the future. Seems like a win-win for merchants and shoppers.

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  • SQL SERVER – Display Datetime in Specific Format – SQL in Sixty Seconds #033 – Video

    - by pinaldave
    A very common requirement of developers is to format datetime to their specific need. Every geographic location has different need of the date formats. Some countries follow the standard of mm/dd/yy and some countries as dd/mm/yy. The need of developer changes as geographic location changes. In SQL Server there are various functions to aid this requirement. There is function CAST, which developers have been using for a long time as well function CONVERT which is a more enhanced version of CAST. In the latest version of SQL Server 2012 a new function FORMAT is introduced as well. In this SQL in Sixty Seconds video we cover two different methods to display the datetime in specific format. 1) CONVERT function and 2) FORMAT function. Let me know what you think of this video. Here is the script which is used in the video: -- http://blog.SQLAuthority.com -- SQL Server 2000/2005/2008/2012 onwards -- Datetime SELECT CONVERT(VARCHAR(30),GETDATE()) AS DateConvert; SELECT CONVERT(VARCHAR(30),GETDATE(),10) AS DateConvert; SELECT CONVERT(VARCHAR(30),GETDATE(),110) AS DateConvert; SELECT CONVERT(VARCHAR(30),GETDATE(),5) AS DateConvert; SELECT CONVERT(VARCHAR(30),GETDATE(),105) AS DateConvert; SELECT CONVERT(VARCHAR(30),GETDATE(),113) AS DateConvert; SELECT CONVERT(VARCHAR(30),GETDATE(),114) AS DateConvert; GO -- SQL Server 2012 onwards -- Various format of Datetime SELECT CONVERT(VARCHAR(30),GETDATE(),113) AS DateConvert; SELECT FORMAT ( GETDATE(), 'dd mon yyyy HH:m:ss:mmm', 'en-US' ) AS DateConvert; SELECT CONVERT(VARCHAR(30),GETDATE(),114) AS DateConvert; SELECT FORMAT ( GETDATE(), 'HH:m:ss:mmm', 'en-US' ) AS DateConvert; GO -- Specific usage of Format function SELECT FORMAT(GETDATE(), N'"Current Time is "dddd MMMM dd, yyyy', 'en-US') AS CurrentTimeString; This video discusses CONVERT and FORMAT in simple manner but the subject is much deeper and there are lots of information to cover along with it. I strongly suggest that you go over related blog posts in next section as there are wealth of knowledge discussed there. Related Tips in SQL in Sixty Seconds: Get Date and Time From Current DateTime – SQL in Sixty Seconds #025 Retrieve – Select Only Date Part From DateTime – Best Practice Get Time in Hour:Minute Format from a Datetime – Get Date Part Only from Datetime DATE and TIME in SQL Server 2008 Function to Round Up Time to Nearest Minutes Interval Get Date Time in Any Format – UDF – User Defined Functions Retrieve – Select Only Date Part From DateTime – Best Practice – Part 2 Difference Between DATETIME and DATETIME2 Saturday Fun Puzzle with SQL Server DATETIME2 and CAST What would you like to see in the next SQL in Sixty Seconds video? Reference: Pinal Dave (http://blog.sqlauthority.com)   Filed under: Database, Pinal Dave, PostADay, SQL, SQL Authority, SQL in Sixty Seconds, SQL Query, SQL Scripts, SQL Server, SQL Server Management Studio, SQL Tips and Tricks, T SQL, Technology, Video Tagged: Excel

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  • When Less is More

    - by aditya.agarkar
    How do you reconcile the fact that while the overall warehouse volume is down you still need more workers in the warehouse to ship all the orders? A WMS customer recently pointed out this seemingly perplexing fact in a customer conference. So what is going on? Didn't we tell you before that for a warehouse the customer is really the "king"? In this case customers are merely responding to a low overall low demand and uncertainty. They do not want to hold down inventory and one of the ways to do that is by decreasing the order size and ordering more frequently. Overall impact to the warehouse? Two words: "More work!!" This is not all. Smaller order sizes also mean challenges from a transportation perspective including a rise in costlier parcel or LTL shipments instead of cheaper TL shipments. Here is a hypothetical scenario where a customer reduces the order size by 10% and increases the order frequency by 10%. As you can see in the following table, the overall volume declines by 1% but the warehouse has to ship roughly 10% more lines. Order Frequency (Line Count)Order Size (Units)Total VolumeChange (%)10010010,000 -110909,900-1% If you want to see how "Less is More" in graphical terms, this is how it appears: Even though the volume is down, there is going to be more work in the warehouse in terms of number of lines shipped. The operators need to pick more discrete orders, pack them into more shipping containers and ship more deliveries. What do you do differently if you are facing this situation?In this case here are some obvious steps to take:Uno: Change your pick methods. If you are used to doing order picks, it needs to go out the door. You need to evaluate batch picking and grouping techniques. Go for cluster picking, go for zone picking, pick and pass...anything that improves your picker productivity. More than anything, cluster picking works like a charm and above all, its simple and very effective. Dos: Are you minimize "touch" points in your pick process? Consider doing one step pick, pack and confirm i.e. pick and pack stuff directly into shipping cartons. Done correctly the container will not require any more "touch" points all the way to the trailer loading. Use cartonization!Tres: Are the being picked from an optimized pick face? Are the items slotted correctly? This needs to be looked into. Consider automated "pull" or "push" replenishment into your pick face and also make sure that high demand items are occupying the golden zones.  Cuatro: Are you tracking labor productivity? If not there needs to be a concerted push for having labor standards in place. Hope you found these ideas useful.

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  • Inflector for .NET

    - by srkirkland
    I was writing conventions for FluentNHibernate the other day and I ran into the need to pluralize a given string and immediately thought of the ruby on rails Inflector.  It turns out there is a .NET library out there also capable of doing word inflection, originally written (I believe) by Andrew Peters, though the link I had no longer works.  The entire Inflector class is only a little over 200 lines long and can be easily included into any project, and contains the Pluralize() method along with a few other helpful methods (like Singularize(), Camelize(), Capitalize(), etc). The Inflector class is available in its entirety from my github repository https://github.com/srkirkland/Inflector.  In addition to the Inflector.cs class I added tests for every single method available so you can gain an understanding of what each method does.  Also, if you are wondering about a specific test case feel free to fork my project and add your own test cases to ensure Inflector does what you expect. Here is an example of some test cases for pluralize: TestData.Add("quiz", "quizzes"); TestData.Add("perspective", "perspectives"); TestData.Add("ox", "oxen"); TestData.Add("buffalo", "buffaloes"); TestData.Add("tomato", "tomatoes"); TestData.Add("dwarf", "dwarves"); TestData.Add("elf", "elves"); TestData.Add("mouse", "mice");   TestData.Add("octopus", "octopi"); TestData.Add("vertex", "vertices"); TestData.Add("matrix", "matrices");   TestData.Add("rice", "rice"); TestData.Add("shoe", "shoes"); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Pretty smart stuff.

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  • Manage Your Twitter Account from the Sidebar in Firefox

    - by Asian Angel
    Are you a Twitter addict and need an easy way to manage your account in Firefox? Now you can access Twitter in your Sidebar or as a separate window with the TwitKit+ extension for Firefox. Accessing TwitKit+ There are three ways that you can access TwitKit+ after installing the extension. The first is by adding the “Toolbar Button” to your browser’s UI. The second and third methods are through the “View & Tools Menus”.   TwitKit+ in Action When you open TwitKit+ for the first time you will see Twitter’s “Public Tweet Stream”. To get started login into your account. Note: If you do not care for the “brown theme” you can select a different one in “Preferences”. Here is a closer look at the top area and the commands available. Notice the “blue arrow symbol” in the upper left corner…very useful if you want to separate TwitKit+ from your main browser window for a bit. Secure Mode, Undock, Preferences, Login/Logout Google Search, Twitter Search, Copy Selection To Status Box, Shorten Selected URL Public, User, Friends, Followers, @ Messages, Direct Messages, Profile Note: To use Google or Twitter search enter your term in the “Status Area” and click on the appropriate service icon. Here is the regular timeline for our account…the “clickable tab buttons” make everything easy to view and work with. You can perform actions such as replying, retweeting, marking as a favorite, etc. using the set of “management buttons” at the bottom of each tweet. To add a new tweet to your timeline enter your text and press “Enter”. A look at the “Following List” for our account. Having a more defined and separate “view categories” set makes this better than directly accessing the Twitter website. Preferences The preferences can be quickly sorted out…choose how often the timeline is updated, name display, favorite URL shortening service, theme, and font size. Note: The default connection setting is for “Secure Access”. Conclusion TwitKit+ makes a nice addition to Firefox for anyone who loves keeping up with Twitter throughout the day. There when you want it and out of your way the rest of the time. Links Download the TwitKit+ extension (Mozilla Add-ons) Similar Articles Productive Geek Tips Move Add-on Management to the Sidebar in FirefoxPreview and Manage Multiple Tabs in Firefox with Tab SidebarDisable Windows Sidebar in VistaQuick Tip: Use Google Talk Sidebar in FirefoxRun Windows Sidebar Gadgets Without the Sidebar TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Enable Check Box Selection in Windows 7 OnlineOCR – Free OCR Service Betting on the Blind Side, a Vanity Fair article 30 Minimal Logo Designs that Say More with Less LEGO Digital Designer – Free Create a Personal Website Quickly using Flavors.me

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  • Manage Your Twitter Account from the Sidebar in Firefox

    - by Asian Angel
    Are you a Twitter addict and need an easy way to manage your account in Firefox? Now you can access Twitter in your Sidebar or as a separate window with the TwitKit+ extension for Firefox. Accessing TwitKit+ There are three ways that you can access TwitKit+ after installing the extension. The first is by adding the “Toolbar Button” to your browser’s UI. The second and third methods are through the “View & Tools Menus”.   TwitKit+ in Action When you open TwitKit+ for the first time you will see Twitter’s “Public Tweet Stream”. To get started login into your account. Note: If you do not care for the “brown theme” you can select a different one in “Preferences”. Here is a closer look at the top area and the commands available. Notice the “blue arrow symbol” in the upper left corner…very useful if you want to separate TwitKit+ from your main browser window for a bit. Secure Mode, Undock, Preferences, Login/Logout Google Search, Twitter Search, Copy Selection To Status Box, Shorten Selected URL Public, User, Friends, Followers, @ Messages, Direct Messages, Profile Note: To use Google or Twitter search enter your term in the “Status Area” and click on the appropriate service icon. Here is the regular timeline for our account…the “clickable tab buttons” make everything easy to view and work with. You can perform actions such as replying, retweeting, marking as a favorite, etc. using the set of “management buttons” at the bottom of each tweet. To add a new tweet to your timeline enter your text and press “Enter”. A look at the “Following List” for our account. Having a more defined and separate “view categories” set makes this better than directly accessing the Twitter website. Preferences The preferences can be quickly sorted out…choose how often the timeline is updated, name display, favorite URL shortening service, theme, and font size. Note: The default connection setting is for “Secure Access”. Conclusion TwitKit+ makes a nice addition to Firefox for anyone who loves keeping up with Twitter throughout the day. There when you want it and out of your way the rest of the time. Links Download the TwitKit+ extension (Mozilla Add-ons) Similar Articles Productive Geek Tips Move Add-on Management to the Sidebar in FirefoxPreview and Manage Multiple Tabs in Firefox with Tab SidebarDisable Windows Sidebar in VistaQuick Tip: Use Google Talk Sidebar in FirefoxRun Windows Sidebar Gadgets Without the Sidebar TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Enable Check Box Selection in Windows 7 OnlineOCR – Free OCR Service Betting on the Blind Side, a Vanity Fair article 30 Minimal Logo Designs that Say More with Less LEGO Digital Designer – Free Create a Personal Website Quickly using Flavors.me

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  • Shutdown Hangs for 5 Minutes on Kubuntu 14.04

    - by Augustinus
    I've had persistent problems with a 5 minute hang at shutdown for the last three versions of Kubuntu (13.04, 13.10, and now 14.04). I suspect this is not a KDE-specific problem. Recently, I performed a fresh installation of Kubuntu 14.04 from a live-USB, and shutdown worked normally for about a week. The hang-up is now happening again, and I can't figure out why. A brief description of the problem: The hang-up occurs with all methods of initiating a normal shutdown: Clicking the shutdown or restart button in KDE, sudo shutdown -h now, sudo reboot The shutdown splash screen appears. Using the down-arrow to access verbose messages, I see "Asking all remaining processes to terminate." This message remains for 5 minutes with no disk activity. Finally, a rapid series of messages flurries to the screen: * All processes ended within 300 seconds... [ OK ] nm-dispatcher.action: Caught signal 15, shutting down... ModemManager[852]: <warn> Could not acquire the 'org.freedesktop.ModemManager1' service name ModemManager[852]: <info> ModemManager is shut down * Deactivating swap... [ OK ] * Unmounting local filesystems... [ OK ] * Will now restart` Possible Sources of the Problem: Before the problem re-appeared, I have mainly been doing routine computing. I have kept the system up-to-date using apt-get upgrade and apt-get dist-upgrade. The only other notable incident was a power failure. I do not have the computer connected to a UPS, so the power failure resulted in an immediate shutdown. Could this have corrupted an important file which must be accessed at shutdown? Is there any way that could cause a 5-minute hang-up? Here is a list of packages that have been updated before the problem appeared: bash iotop dpkg dpkg-dev python3-software-properties libdpkg-perl software-properties-kde software-properties-common akonadi-backend-mysql libakonadiprotocolinternals1 akonadi-server firefox-locale-en firefox flashplugin-installer libqapt2 libqapt2-runtime thunderbird openjdk-7-jre-headless thunderbird-locale-en kubuntu-driver-manager qapt-deb-installer openjdk-7-jre qapt-batch icedtea-7-jre-jamvm libelf1 dpkg dpkg-dev libdpkg-perl libjbig0 gettext-base libgettextpo-dev libssl1.0.0 libgettextpo0 libasprintf-dev linux-headers-3.13.0-24 gettext libasprintf0c2 linux-headers-3.13.0-24-generic openssl linux-libc-dev gstreamer0.10-qapt kubuntu-desktop linux-image-extra-3.13.0-24-generic linux-image-3.13.0-24-generic I would appreciate any help with this.

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  • SQL SERVER – Working with FileTables in SQL Server 2012 – Part 1 – Setting Up Environment

    - by pinaldave
    Filestream is a very interesting feature, and an enhancement of FileTable with Filestream is equally exciting. Today in this post, we will learn how to set up the FileTable Environment in SQL Server. The major advantage of FileTable is it has Windows API compatibility for file data stored within an SQL Server database. In simpler words, FileTables remove a barrier so that SQL Server can be used for the storage and management of unstructured data that are currently residing as files on file servers. Another advantage is that the Windows Application Compatibility for their existing Windows applications enables to see these data as files in the file system. This way, you can use SQL Server to access the data using T-SQL enhancements, and Windows can access the file using its applications. So for the first step, you will need to enable the Filestream feature at the database level in order to use the FileTable. -- Enable Filestream EXEC sp_configure filestream_access_level, 2 RECONFIGURE GO -- Create Database CREATE DATABASE FileTableDB ON PRIMARY (Name = FileTableDB, FILENAME = 'D:\FileTable\FTDB.mdf'), FILEGROUP FTFG CONTAINS FILESTREAM (NAME = FileTableFS, FILENAME='D:\FileTable\FS') LOG ON (Name = FileTableDBLog, FILENAME = 'D:\FileTable\FTDBLog.ldf') WITH FILESTREAM (NON_TRANSACTED_ACCESS = FULL, DIRECTORY_NAME = N'FileTableDB'); GO Now, you can run the following code and figure out if FileStream options are enabled at the database level. -- Check the Filestream Options SELECT DB_NAME(database_id), non_transacted_access, non_transacted_access_desc FROM sys.database_filestream_options; GO You can see the resultset of the above query which returns resultset as the following image shows. As you can see , the file level access is set to 2 (filestream enabled). Now let us create the filetable in the newly created database. -- Create FileTable Table USE FileTableDB GO CREATE TABLE FileTableTb AS FileTable WITH (FileTable_Directory = 'FileTableTb_Dir'); GO Now you can select data using a regular select table. SELECT * FROM FileTableTb GO It will return all the important columns which are related to the file. It will provide details like filesize, archived, file types etc. You can also see the FileTable in SQL Server Management Studio. Go to Databases >> Newly Created Database (FileTableDB) >> Expand Tables Here, you will see a new folder which says “FileTables”. When expanded, it gives the name of the newly created FileTableTb. You can right click on the newly created table and click on “Explore FileTable Directory”. This will open up the folder where the FileTable data will be stored. When you click on the option, it will open up the following folder in my local machine where the FileTable data will be stored: \\127.0.0.1\mssqlserver\FileTableDB\FileTableTb_Dir In tomorrow’s blog post as Part 2, we will go over two methods of inserting the data into this FileTable. Reference : Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Filestream

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  • Scaling-out Your Services by Message Bus based WCF Transport Extension &ndash; Part 1 &ndash; Background

    - by Shaun
    Cloud computing gives us more flexibility on the computing resource, we can provision and deploy an application or service with multiple instances over multiple machines. With the increment of the service instances, how to balance the incoming message and workload would become a new challenge. Currently there are two approaches we can use to pass the incoming messages to the service instances, I would like call them dispatcher mode and pulling mode.   Dispatcher Mode The dispatcher mode introduces a role which takes the responsible to find the best service instance to process the request. The image below describes the sharp of this mode. There are four clients communicate with the service through the underlying transportation. For example, if we are using HTTP the clients might be connecting to the same service URL. On the server side there’s a dispatcher listening on this URL and try to retrieve all messages. When a message came in, the dispatcher will find a proper service instance to process it. There are three mechanism to find the instance: Round-robin: Dispatcher will always send the message to the next instance. For example, if the dispatcher sent the message to instance 2, then the next message will be sent to instance 3, regardless if instance 3 is busy or not at that moment. Random: Dispatcher will find a service instance randomly, and same as the round-robin mode it regardless if the instance is busy or not. Sticky: Dispatcher will send all related messages to the same service instance. This approach always being used if the service methods are state-ful or session-ful. But as you can see, all of these approaches are not really load balanced. The clients will send messages at any time, and each message might take different process duration on the server side. This means in some cases, some of the service instances are very busy while others are almost idle. For example, if we were using round-robin mode, it could be happened that most of the simple task messages were passed to instance 1 while the complex ones were sent to instance 3, even though instance 1 should be idle. This brings some problem in our architecture. The first one is that, the response to the clients might be longer than it should be. As it’s shown in the figure above, message 6 and 9 can be processed by instance 1 or instance 2, but in reality they were dispatched to the busy instance 3 since the dispatcher and round-robin mode. Secondly, if there are many requests came from the clients in a very short period, service instances might be filled by tons of pending tasks and some instances might be crashed. Third, if we are using some cloud platform to host our service instances, for example the Windows Azure, the computing resource is billed by service deployment period instead of the actual CPU usage. This means if any service instance is idle it is wasting our money! Last one, the dispatcher would be the bottleneck of our system since all incoming messages must be routed by the dispatcher. If we are using HTTP or TCP as the transport, the dispatcher would be a network load balance. If we wants more capacity, we have to scale-up, or buy a hardware load balance which is very expensive, as well as scaling-out the service instances. Pulling Mode Pulling mode doesn’t need a dispatcher to route the messages. All service instances are listening to the same transport and try to retrieve the next proper message to process if they are idle. Since there is no dispatcher in pulling mode, it requires some features on the transportation. The transportation must support multiple client connection and server listening. HTTP and TCP doesn’t allow multiple clients are listening on the same address and port, so it cannot be used in pulling mode directly. All messages in the transportation must be FIFO, which means the old message must be received before the new one. Message selection would be a plus on the transportation. This means both service and client can specify some selection criteria and just receive some specified kinds of messages. This feature is not mandatory but would be very useful when implementing the request reply and duplex WCF channel modes. Otherwise we must have a memory dictionary to store the reply messages. I will explain more about this in the following articles. Message bus, or the message queue would be best candidate as the transportation when using the pulling mode. First, it allows multiple application to listen on the same queue, and it’s FIFO. Some of the message bus also support the message selection, such as TIBCO EMS, RabbitMQ. Some others provide in memory dictionary which can store the reply messages, for example the Redis. The principle of pulling mode is to let the service instances self-managed. This means each instance will try to retrieve the next pending incoming message if they finished the current task. This gives us more benefit and can solve the problems we met with in the dispatcher mode. The incoming message will be received to the best instance to process, which means this will be very balanced. And it will not happen that some instances are busy while other are idle, since the idle one will retrieve more tasks to make them busy. Since all instances are try their best to be busy we can use less instances than dispatcher mode, which more cost effective. Since there’s no dispatcher in the system, there is no bottleneck. When we introduced more service instances, in dispatcher mode we have to change something to let the dispatcher know the new instances. But in pulling mode since all service instance are self-managed, there no extra change at all. If there are many incoming messages, since the message bus can queue them in the transportation, service instances would not be crashed. All above are the benefits using the pulling mode, but it will introduce some problem as well. The process tracking and debugging become more difficult. Since the service instances are self-managed, we cannot know which instance will process the message. So we need more information to support debug and track. Real-time response may not be supported. All service instances will process the next message after the current one has done, if we have some real-time request this may not be a good solution. Compare with the Pros and Cons above, the pulling mode would a better solution for the distributed system architecture. Because what we need more is the scalability, cost-effect and the self-management.   WCF and WCF Transport Extensibility Windows Communication Foundation (WCF) is a framework for building service-oriented applications. In the .NET world WCF is the best way to implement the service. In this series I’m going to demonstrate how to implement the pulling mode on top of a message bus by extending the WCF. I don’t want to deep into every related field in WCF but will highlight its transport extensibility. When we implemented an RPC foundation there are many aspects we need to deal with, for example the message encoding, encryption, authentication and message sending and receiving. In WCF, each aspect is represented by a channel. A message will be passed through all necessary channels and finally send to the underlying transportation. And on the other side the message will be received from the transport and though the same channels until the business logic. This mode is called “Channel Stack” in WCF, and the last channel in the channel stack must always be a transport channel, which takes the responsible for sending and receiving the messages. As we are going to implement the WCF over message bus and implement the pulling mode scaling-out solution, we need to create our own transport channel so that the client and service can exchange messages over our bus. Before we deep into the transport channel, let’s have a look on the message exchange patterns that WCF defines. Message exchange pattern (MEP) defines how client and service exchange the messages over the transportation. WCF defines 3 basic MEPs which are datagram, Request-Reply and Duplex. Datagram: Also known as one-way, or fire-forgot mode. The message sent from the client to the service, and no need any reply from the service. The client doesn’t care about the message result at all. Request-Reply: Very common used pattern. The client send the request message to the service and wait until the reply message comes from the service. Duplex: The client sent message to the service, when the service processing the message it can callback to the client. When callback the service would be like a client while the client would be like a service. In WCF, each MEP represent some channels associated. MEP Channels Datagram IInputChannel, IOutputChannel Request-Reply IRequestChannel, IReplyChannel Duplex IDuplexChannel And the channels are created by ChannelListener on the server side, and ChannelFactory on the client side. The ChannelListener and ChannelFactory are created by the TransportBindingElement. The TransportBindingElement is created by the Binding, which can be defined as a new binding or from a custom binding. For more information about the transport channel mode, please refer to the MSDN document. The figure below shows the transport channel objects when using the request-reply MEP. And this is the datagram MEP. And this is the duplex MEP. After investigated the WCF transport architecture, channel mode and MEP, we finally identified what we should do to extend our message bus based transport layer. They are: Binding: (Optional) Defines the channel elements in the channel stack and added our transport binding element at the bottom of the stack. But we can use the build-in CustomBinding as well. TransportBindingElement: Defines which MEP is supported in our transport and create the related ChannelListener and ChannelFactory. This also defines the scheme of the endpoint if using this transport. ChannelListener: Create the server side channel based on the MEP it’s. We can have one ChannelListener to create channels for all supported MEPs, or we can have ChannelListener for each MEP. In this series I will use the second approach. ChannelFactory: Create the client side channel based on the MEP it’s. We can have one ChannelFactory to create channels for all supported MEPs, or we can have ChannelFactory for each MEP. In this series I will use the second approach. Channels: Based on the MEPs we want to support, we need to implement the channels accordingly. For example, if we want our transport support Request-Reply mode we should implement IRequestChannel and IReplyChannel. In this series I will implement all 3 MEPs listed above one by one. Scaffold: In order to make our transport extension works we also need to implement some scaffold stuff. For example we need some classes to send and receive message though out message bus. We also need some codes to read and write the WCF message, etc.. These are not necessary but would be very useful in our example.   Message Bus There is only one thing remained before we can begin to implement our scaling-out support WCF transport, which is the message bus. As I mentioned above, the message bus must have some features to fulfill all the WCF MEPs. In my company we will be using TIBCO EMS, which is an enterprise message bus product. And I have said before we can use any message bus production if it’s satisfied with our requests. Here I would like to introduce an interface to separate the message bus from the WCF. This allows us to implement the bus operations by any kinds bus we are going to use. The interface would be like this. 1: public interface IBus : IDisposable 2: { 3: string SendRequest(string message, bool fromClient, string from, string to = null); 4:  5: void SendReply(string message, bool fromClient, string replyTo); 6:  7: BusMessage Receive(bool fromClient, string replyTo); 8: } There are only three methods for the bus interface. Let me explain one by one. The SendRequest method takes the responsible for sending the request message into the bus. The parameters description are: message: The WCF message content. fromClient: Indicates if this message was came from the client. from: The channel ID that this message was sent from. The channel ID will be generated when any kinds of channel was created, which will be explained in the following articles. to: The channel ID that this message should be received. In Request-Reply and Duplex MEP this is necessary since the reply message must be received by the channel which sent the related request message. The SendReply method takes the responsible for sending the reply message. It’s very similar as the previous one but no “from” parameter. This is because it’s no need to reply a reply message again in any MEPs. The Receive method takes the responsible for waiting for a incoming message, includes the request message and specified reply message. It returned a BusMessage object, which contains some information about the channel information. The code of the BusMessage class is 1: public class BusMessage 2: { 3: public string MessageID { get; private set; } 4: public string From { get; private set; } 5: public string ReplyTo { get; private set; } 6: public string Content { get; private set; } 7:  8: public BusMessage(string messageId, string fromChannelId, string replyToChannelId, string content) 9: { 10: MessageID = messageId; 11: From = fromChannelId; 12: ReplyTo = replyToChannelId; 13: Content = content; 14: } 15: } Now let’s implement a message bus based on the IBus interface. Since I don’t want you to buy and install the TIBCO EMS or any other message bus products, I will implement an in process memory bus. This bus is only for test and sample purpose. It can only be used if the service and client are in the same process. Very straightforward. 1: public class InProcMessageBus : IBus 2: { 3: private readonly ConcurrentDictionary<Guid, InProcMessageEntity> _queue; 4: private readonly object _lock; 5:  6: public InProcMessageBus() 7: { 8: _queue = new ConcurrentDictionary<Guid, InProcMessageEntity>(); 9: _lock = new object(); 10: } 11:  12: public string SendRequest(string message, bool fromClient, string from, string to = null) 13: { 14: var entity = new InProcMessageEntity(message, fromClient, from, to); 15: _queue.TryAdd(entity.ID, entity); 16: return entity.ID.ToString(); 17: } 18:  19: public void SendReply(string message, bool fromClient, string replyTo) 20: { 21: var entity = new InProcMessageEntity(message, fromClient, null, replyTo); 22: _queue.TryAdd(entity.ID, entity); 23: } 24:  25: public BusMessage Receive(bool fromClient, string replyTo) 26: { 27: InProcMessageEntity e = null; 28: while (true) 29: { 30: lock (_lock) 31: { 32: var entity = _queue 33: .Where(kvp => kvp.Value.FromClient == fromClient && (kvp.Value.To == replyTo || string.IsNullOrWhiteSpace(kvp.Value.To))) 34: .FirstOrDefault(); 35: if (entity.Key != Guid.Empty && entity.Value != null) 36: { 37: _queue.TryRemove(entity.Key, out e); 38: } 39: } 40: if (e == null) 41: { 42: Thread.Sleep(100); 43: } 44: else 45: { 46: return new BusMessage(e.ID.ToString(), e.From, e.To, e.Content); 47: } 48: } 49: } 50:  51: public void Dispose() 52: { 53: } 54: } The InProcMessageBus stores the messages in the objects of InProcMessageEntity, which can take some extra information beside the WCF message itself. 1: public class InProcMessageEntity 2: { 3: public Guid ID { get; set; } 4: public string Content { get; set; } 5: public bool FromClient { get; set; } 6: public string From { get; set; } 7: public string To { get; set; } 8:  9: public InProcMessageEntity() 10: : this(string.Empty, false, string.Empty, string.Empty) 11: { 12: } 13:  14: public InProcMessageEntity(string content, bool fromClient, string from, string to) 15: { 16: ID = Guid.NewGuid(); 17: Content = content; 18: FromClient = fromClient; 19: From = from; 20: To = to; 21: } 22: }   Summary OK, now I have all necessary stuff ready. The next step would be implementing our WCF message bus transport extension. In this post I described two scaling-out approaches on the service side especially if we are using the cloud platform: dispatcher mode and pulling mode. And I compared the Pros and Cons of them. Then I introduced the WCF channel stack, channel mode and the transport extension part, and identified what we should do to create our own WCF transport extension, to let our WCF services using pulling mode based on a message bus. And finally I provided some classes that need to be used in the future posts that working against an in process memory message bus, for the demonstration purpose only. In the next post I will begin to implement the transport extension step by step.   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.

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