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• The way I think about Diagnostic tools

  - by Daniel Moth

  Every software has issues, or as we like to call them "bugs". That is not a discussion point, just a mere fact. It follows that an important skill for developers is to be able to diagnose issues in their code. Of course we need to advance our tools and techniques so we can prevent bugs getting into the code (e.g. unit testing), but beyond designing great software, diagnosing bugs is an equally important skill. To diagnose issues, the most important assets are good techniques, skill, experience, and maybe talent. What also helps is having good diagnostic tools and what helps further is knowing all the features that they offer and how to use them. The following classification is how I like to think of diagnostics. Note that like with any attempt to bucketize anything, you run into overlapping areas and blurry lines. Nevertheless, I will continue sharing my generalizations ;-) It is important to identify at the outset if you are dealing with a performance or a correctness issue. If you have a performance issue, use a profiler. I hear people saying "I am using the debugger to debug a performance issue", and that is fine, but do know that a dedicated profiler is the tool for that job. Just because you don't need them all the time and typically they cost more plus you are not as familiar with them as you are with the debugger, doesn't mean you shouldn't invest in one and instead try to exclusively use the wrong tool for the job. Visual Studio has a profiler and a concurrency visualizer (for profiling multi-threaded apps). If you have a correctness issue, then you have several options - that's next :-) This is how I think of identifying a correctness issue Do you want a tool to find the issue for you at design time? The compiler is such a tool - it gives you an exact list of errors. Compilers now also offer warnings, which is their way of saying "this may be an error, but I am not smart enough to know for sure". There are also static analysis tools, which go a step further than the compiler in identifying issues in your code, sometimes with the aid of code annotations and other times just by pointing them at your raw source. An example is FxCop and much more in Visual Studio 11 Code Analysis. Do you want a tool to find the issue for you with code execution? Just like static tools, there are also dynamic analysis tools that instead of statically analyzing your code, they analyze what your code does dynamically at runtime. Whether you have to setup some unit tests to invoke your code at runtime, or have to manually run your app (and interact with it) under the tool, or have to use a script to execute your binary under the tool… that varies. The result is still a list of issues for you to address after the analysis is complete or a pause of the execution when the first issue is encountered. If a code path was not taken, no analysis for it will exist, obviously. An example is the GPU Race detection tool that I'll be talking about on the C++ AMP team blog. Another example is the MSR concurrency CHESS tool. Do you want you to find the issue at design time using a tool? Perform a code walkthrough on your own or with colleagues. There are code review tools that go beyond just diffing sources, and they help you with that aspect too. For example, there is a new one in Visual Studio 11 and searching with my favorite search engine yielded this article based on the Developer Preview. Do you want you to find the issue with code execution? Use a debugger - let’s break this down further next. This is how I think of debugging: There is post mortem debugging. That means your code has executed and you did something in order to examine what happened during its execution. This can vary from manual printf and other tracing statements to trace events (e.g. ETW) to taking dumps. In all cases, you are left with some artifact that you examine after the fact (after code execution) to discern what took place hoping it will help you find the bug. Learn how to debug dump files in Visual Studio. There is live debugging. I will elaborate on this in a separate post, but this is where you inspect the state of your program during its execution, and try to find what the problem is. More from me in a separate post on live debugging. There is a hybrid of live plus post-mortem debugging. This is for example what tools like IntelliTrace offer. If you are a tools vendor interested in the diagnostics space, it helps to understand where in the above classification your tool excels, where its primary strength is, so you can market it as such. Then it helps to see which of the other areas above your tool touches on, and how you can make it even better there. Finally, see what areas your tool doesn't help at all with, and evaluate whether it should or continue to stay clear. Even though the classification helps us think about this space, the reality is that the best tools are either extremely excellent in only one of this areas, or more often very good across a number of them. Another approach is to offer a toolset covering all areas, with appropriate integration and hand off points from one to the other. Anyway, with that brain dump out of the way, in follow-up posts I will dive into live debugging, and specifically live debugging in Visual Studio - stay tuned if that interests you. Comments about this post by Daniel Moth welcome at the original blog.

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• Getting Started with Prism (aka Composite Application Guidance for WPF and Silverlight)

  - by dotneteer

  Overview Prism is a framework from the Microsoft Patterns and Practice team that allow you to create WPF and Silverlight in a modular way. It is especially valuable for larger projects in which a large number of developers can develop in parallel. Prism achieves its goal by supplying several services: · Dependency Injection (DI) and Inversion of control (IoC): By using DI, Prism takes away the responsibility of instantiating and managing the life time of dependency objects from individual components to a container. Prism relies on containers to discover, manage and compose large number of objects. By varying the configuration, the container can also inject mock objects for unit testing. Out of the box, Prism supports Unity and MEF as container although it is possible to use other containers by subclassing the Bootstrapper class. · Modularity and Region: Prism supplies the framework to split application into modules from the application shell. Each module is a library project that contains both UI and code and is responsible to initialize itself when loaded by the shell. Each window can be further divided into regions. A region is a user control with associated model. · Model, view and view-model (MVVM) pattern: Prism promotes the user MVVM. The use of DI container makes it much easier to inject model into view. WPF already has excellent data binding and commanding mechanism. To be productive with Prism, it is important to understand WPF data binding and commanding well. · Event-aggregation: Prism promotes loosely coupled components. Prism discourages for components from different modules to communicate each other, thus leading to dependency. Instead, Prism supplies an event-aggregation mechanism that allows components to publish and subscribe events without knowing each other. Architecture In the following, I will go into a little more detail on the services provided by Prism. Bootstrapper In a typical WPF application, application start-up is controls by App.xaml and its code behind. The main window of the application is typically specified in the App.xaml file. In a Prism application, we start a bootstrapper in the App class and delegate the duty of main window to the bootstrapper. The bootstrapper will start a dependency-injection container so all future object instantiations are managed by the container. Out of box, Prism provides the UnityBootstrapper and MefUnityBootstrapper abstract classes. All application needs to either provide a concrete implementation of one of these bootstrappers, or alternatively, subclass the Bootstrapper class with another DI container. A concrete bootstrapper class must implement the CreateShell method. Its responsibility is to resolve and create the Shell object through the DI container to serve as the main window for the application. The other important method to override is ConfigureModuleCatalog. The bootstrapper can register modules for the application. In a more advance scenario, an application does not have to know all its modules at compile time. Modules can be discovered at run time. Readers to refer to one of the Open Modularity Quick Starts for more information. Modules Once modules are registered with or discovered by Prism, they are instantiated by the DI container and their Initialize method is called. The DI container can inject into a module a region registry that implements IRegionViewRegistry interface. The module, in its Initialize method, can then call RegisterViewWithRegion method of the registry to register its regions. Regions Regions, once registered, are managed by the RegionManager. The shell can then load regions either through the RegionManager.RegionName attached property or dynamically through code. When a view is created by the region manager, the DI container can inject view model and other services into the view. The view then has a reference to the view model through which it can interact with backend services. Service locator Although it is possible to inject services into dependent classes through a DI container, an alternative way is to use the ServiceLocator to retrieve a service on demard. Prism supplies a service locator implementation and it is possible to get an instance of the service by calling: ServiceLocator.Current.GetInstance<IServiceType>() Event aggregator Prism supplies an IEventAggregator interface and implementation that can be injected into any class that needs to communicate with each other in a loosely-coupled fashion. The event aggregator uses a publisher/subscriber model. A class can publishes an event by calling eventAggregator.GetEvent<EventType>().Publish(parameter) to raise an event. Other classes can subscribe the event by calling eventAggregator.GetEvent<EventType>().Subscribe(EventHandler, other options). Getting started The easiest way to get started with Prism is to go through the Prism Hands-On labs and look at the Hello World QuickStart. The Hello World QuickStart shows how bootstrapper, modules and region works. Next, I would recommend you to look at the Stock Trader Reference Implementation. It is a more in depth example that resemble we want to set up an application. Several other QuickStarts cover individual Prism services. Some scenarios, such as dynamic module discovery, are more advanced. Apart from the official prism document, you can get an overview by reading Glen Block’s MSDN Magazine article. I have found the best free training material is from the Boise Code Camp. To be effective with Prism, it is important to understands key concepts of WPF well first, such as the DependencyProperty system, data binding, resource, theme and ICommand. It is also important to know your DI container of choice well. I will try to explorer these subjects in depth in the future. Testimony Recently, I worked on a desktop WPF application using Prism. I had a wonderful experience with Prism. The Prism is flexible enough even in the presence of third party controls such as Telerik WPF controls. We have never encountered any significant obstacle.

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• SQL SERVER – SSIS Parameters in Parent-Child ETL Architectures – Notes from the Field #040

  - by Pinal Dave

  [Notes from Pinal]: SSIS is very well explored subject, however, there are so many interesting elements when we read, we learn something new. A similar concept has been Parent-Child ETL architecture’s relationship in SSIS. Linchpin People are database coaches and wellness experts for a data driven world. In this 40th episode of the Notes from the Fields series database expert Tim Mitchell (partner at Linchpin People) shares very interesting conversation related to how to understand SSIS Parameters in Parent-Child ETL Architectures. In this brief Notes from the Field post, I will review the use of SSIS parameters in parent-child ETL architectures. A very common design pattern used in SQL Server Integration Services is one I call the parent-child pattern.  Simply put, this is a pattern in which packages are executed by other packages.  An ETL infrastructure built using small, single-purpose packages is very often easier to develop, debug, and troubleshoot than large, monolithic packages.  For a more in-depth look at parent-child architectures, check out my earlier blog post on this topic. When using the parent-child design pattern, you will frequently need to pass values from the calling (parent) package to the called (child) package.  In older versions of SSIS, this process was possible but not necessarily simple.  When using SSIS 2005 or 2008, or even when using SSIS 2012 or 2014 in package deployment mode, you would have to create package configurations to pass values from parent to child packages.  Package configurations, while effective, were not the easiest tool to work with.  Fortunately, starting with SSIS in SQL Server 2012, you can now use package parameters for this purpose. In the example I will use for this demonstration, I’ll create two packages: one intended for use as a child package, and the other configured to execute said child package.  In the parent package I’m going to build a for each loop container in SSIS, and use package parameters to pass in a value – specifically, a ClientID – for each iteration of the loop.  The child package will be executed from within the for each loop, and will create one output file for each client, with the source query and filename dependent on the ClientID received from the parent package. Configuring the Child and Parent Packages When you create a new package, you’ll see the Parameters tab at the package level.  Clicking over to that tab allows you to add, edit, or delete package parameters. As shown above, the sample package has two parameters.  Note that I’ve set the name, data type, and default value for each of these.  Also note the column entitled Required: this allows me to specify whether the parameter value is optional (the default behavior) or required for package execution.  In this example, I have one parameter that is required, and the other is not. Let’s shift over to the parent package briefly, and demonstrate how to supply values to these parameters in the child package.  Using the execute package task, you can easily map variable values in the parent package to parameters in the child package. The execute package task in the parent package, shown above, has the variable vThisClient from the parent package mapped to the pClientID parameter shown earlier in the child package.  Note that there is no value mapped to the child package parameter named pOutputFolder.  Since this parameter has the Required property set to False, we don’t have to specify a value for it, which will cause that parameter to use the default value we supplied when designing the child pacakge. The last step in the parent package is to create the for each loop container I mentioned earlier, and place the execute package task inside it.  I’m using an object variable to store the distinct client ID values, and I use that as the iterator for the loop (I describe how to do this more in depth here).  For each iteration of the loop, a different client ID value will be passed into the child package parameter. The final step is to configure the child package to actually do something meaningful with the parameter values passed into it.  In this case, I’ve modified the OleDB source query to use the pClientID value in the WHERE clause of the query to restrict results for each iteration to a single client’s data.  Additionally, I’ll use both the pClientID and pOutputFolder parameters to dynamically build the output filename. As shown, the pClientID is used in the WHERE clause, so we only get the current client’s invoices for each iteration of the loop. For the flat file connection, I’m setting the Connection String property using an expression that engages both of the parameters for this package, as shown above. Parting Thoughts There are many uses for package parameters beyond a simple parent-child design pattern.  For example, you can create standalone packages (those not intended to be used as a child package) and still use parameters.  Parameter values may be supplied to a package directly at runtime by a SQL Server Agent job, through the command line (via dtexec.exe), or through T-SQL. Also, you can also have project parameters as well as package parameters.  Project parameters work in much the same way as package parameters, but the parameters apply to all packages in a project, not just a single package. Conclusion Of the numerous advantages of using catalog deployment model in SSIS 2012 and beyond, package parameters are near the top of the list.  Parameters allow you to easily share values from parent to child packages, enabling more dynamic behavior and better code encapsulation. If you want me to take a look at your server and its settings, or if your server is facing any issue we can Fix Your SQL Server. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: Notes from the Field, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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• The Krewe App Post-Mortem

  - by Chris Gardner

  Originally posted on: http://geekswithblogs.net/freestylecoding/archive/2014/05/23/the-krewe-app-post-mortem.aspxNow that teched has come and gone, I thought I would use this opportunity to do a little post-mortem on The Krewe app. It is one thing to test the app at home. It is a completely different animal to see how it responds in the environment TechEd creates. At a future time, I will list all the things that I would like to change with the app. At this point, I will find some good way to get community feedback. I want to break all this down screen by screen. We'll start with the screen I got right. The first of these is the events calendar. This is the one screen that, to you guys, just worked. However, there was an issue here. When I wrote v1 for last year, I was lazy and placed everything in CST. This caused problems with the achievements, which I will explain later. Furthermore, the event locations were not check-in locations. This created another problem with the achievements. Next, we get to the Twitter page. For what this page does, it works great. For those that don't know, I have an Azure Worker Role that polls Twitter pretty close to the rate limit. I cache these results in my database, and serve them upon request. This gives me great control over the content. I just have to remember to flush past tweets after a period, to save database growth. The next screen is the check-in screen. This screen has been the bane of my existence since I first created the thing. Last year, I used a background task to check people out of locations after they traveled. This year, I removed the background task in favor of a foursquare model. You are checked out after 3 hours or when you check-in to some other location. This seemed to work well, until those pesky achievements came into the mix. Again, more on this later. Next, I want to address the Connect and Connections screens together. I wanted to use some of the capabilities of the phone, and NFC seemed a natural choice. From this, I came up with the gamification aspects of the app. Since we are, fundamentally, a networking organization, I wanted to encourage people to actually network. Users could make and share a profile, similar to a virtual business card. I just had to figure out how to get people to use the feature. Why not just give someone a business card? Thus, the achievements were born. This was such a good idea. It would have been a great idea, if I have come up with it about two months earlier... When I came up with these ideas, I had about 2 weeks to implement them. Version 1 of the app was, basically, a pure consumption app. We provided data and centralized it. With version 2, the app became a much more interactive experience. The API was not ready for this change in such a short period of time. Most of this became apparent when I started implementing the achievements. The achievements based on count and specific person when fairly easy. The problem came with tying them to locations and events. This took some true SQL kung fu. This also showed me the rookie mistake of putting CST, not UTC, in the database. Once I got all of that cleaned up, I had to find a way to get the achievement system to talk to the phone. I knew I needed to be able to dynamically add achievements. I wouldn't know the precise location of some things until I got to Houston. I wanted the server to approve the achievements. This, unfortunately, required a decent data connection. Some achievements required GPS levels of location accuracy in areas of network triangulation. All of this became a huge nightmare. My flagship feature was based on some silly assumptions. Still, I managed to get 31 people to get the first achievement (Make 1 Connection.) Quite a few of those managed to get to the higher levels. Soon, I will post a list of the feature and changes that need to happen to the API. This includes things like proper objects for communication, geo-fencing, and caching. However, that is for another day.

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• Working with Reporting Services Filters–Part 1

  - by smisner

  There are two ways that you can filter data in Reporting Services. The first way, which usually provides a faster performance, is to use query parameters to apply a filter using the WHERE clause in a SQL statement. In that case, the structure of the filter depends upon the syntax recognized by the source database. Another way to filter data in Reporting Services is to apply a filter to a dataset, data region, or a group. Using this latter method, you can even apply multiple filters. However, the use of filter operators or the setup of multiple filters is not always obvious, so in this series of posts, I'll provide some more information about the configuration of filters. First, why not use query parameters exclusively for filtering? Here are a few reasons: You might want to apply a filter to part of the report, but not all of the report. Your dataset might retrieve data from a stored procedure, and doesn't allow you to pass a query parameter for filtering purposes. Your report might be set up as a snapshot on the report server and, in that case, cannot be dynamically filtered based on a query parameter. Next, let's look at how to set up a report filter in general. The process is the same whether you are applying the filter to a dataset, data region, or a group. When you go to the Filters page in the Properties dialog box for whichever of these items you selected (dataset, data region, group), you click the Add button to create a new filter. The interface looks like this: The Expression field is usually a field in the dataset, so to make it easier for you to make a selection,the drop-down list displays all of the current dataset fields. But notice the expression button to the right, which means that you can set up any type of expression-not just a dataset field. To the right of the expression button, you'll find a data type drop-down list. It's important to specify the correct data type for the field or expression you're using. Now for the operators. Here's a list of the options that you have: This Operator Performs This Action =, <>, >, >=, <, <=, Like Compares expression to value Top N, Bottom N Compares expression to Top (Bottom) set of N values (N = integer) Top %, Bottom % Compares expression to Top (Bottom) N percent of values (N = integer or float) Between Determines whether expression is between two values, inclusive In Determines whether expression is found in list of values Last, the Value is what you're comparing to the expression using the operator. The construction of a filter using some operators (=, <>, >, etc.) is fairly simple. If my dataset (for AdventureWorks data) has a Category field, and I have a parameter that prompts the user for a single category, I can set up a filter like this: Expression Data Type Operator Value [Category] Text = [@Category] But if I set the parameter to accept multiple values, I need to change the operator from = to In, just as I would have to do if I were using a query parameter. The parameter expression, [@Category], which translates to =Parameters!Category.Value, doesn’t need to change because it represents an array as soon as I change the parameter to allow multiple values. The “In” operator requires an array. With that in mind, let’s consider a variation on Value. Let’s say that I have a parameter that prompts the user for a particular year – and for simplicity’s sake, this parameter only allows a single value, and I have an expression that evaluates the previous year based on the user’s selection. Then I want to use these two values in two separate filters with an OR condition. That is, I want to filter either by the year selected OR by the year that was computed. If I create two filters, one for each year (as shown below), then the report will only display results if BOTH filter conditions are met – which would never be true. Expression Data Type Operator Value [CalendarYear] Integer = [@Year] [CalendarYear] Integer = =Parameters!Year.Value-1 To handle this scenario, we need to create a single filter that uses the “In” operator, and then set up the Value expression as an array. To create an array, we use the Split function after creating a string that concatenates the two values (highlighted in yellow) as shown below. Expression Data Type Operator Value =Cstr(Fields!CalendarYear.Value) Text In =Split( CStr(Parameters!Year.Value) + ”,” + CStr(Parameters!Year.Value-1) , “,”) Note that in this case, I had to apply a string conversion on the year integer so that I could concatenate the parameter selection with the calculated year. Pay attention to the second argument of the Split function—you must use a comma delimiter for the result to work correctly with the In operator. I also had to change the Expression value from [CalendarYear] (or =Fields!CalendarYear.Value) so that the expression would return a string that I could compare with the values in the string array. More fun with filter expressions in future posts!

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• Goodbye XML&hellip; Hello YAML (part 2)

  - by Brian Genisio's House Of Bilz

  Part 1 After I explained my motivation for using YAML instead of XML for my data, I got a lot of people asking me what type of tooling is available in the .Net space for consuming YAML.  In this post, I will discuss a nice tooling option as well as describe some small modifications to leverage the extremely powerful dynamic capabilities of C# 4.0.  I will be referring to the following YAML file throughout this post Recipe: Title: Macaroni and Cheese Description: My favorite comfort food. Author: Brian Genisio TimeToPrepare: 30 Minutes Ingredients: - Name: Cheese Quantity: 3 Units: cups - Name: Macaroni Quantity: 16 Units: oz Steps: - Number: 1 Description: Cook the macaroni - Number: 2 Description: Melt the cheese - Number: 3 Description: Mix the cooked macaroni with the melted cheese Tooling It turns out that there are several implementations of YAML tools out there.  The neatest one, in my opinion, is YAML for .NET, Visual Studio and Powershell.  It includes a great editor plug-in for Visual Studio as well as YamlCore, which is a parsing engine for .Net.  It is in active development still, but it is certainly enough to get you going with YAML in .Net.  Start by referenceing YamlCore.dll, load your document, and you are on your way.  Here is an example of using the parser to get the title of the Recipe: var yaml = YamlLanguage.FileTo("Data.yaml") as Hashtable; var recipe = yaml["Recipe"] as Hashtable; var title = recipe["Title"] as string; In a similar way, you can access data in the Ingredients set: var yaml = YamlLanguage.FileTo("Data.yaml") as Hashtable; var recipe = yaml["Recipe"] as Hashtable; var ingredients = recipe["Ingredients"] as ArrayList; foreach (Hashtable ingredient in ingredients) { var name = ingredient["Name"] as string; } You may have noticed that YamlCore uses non-generic Hashtables and ArrayLists.  This is because YamlCore was designed to work in all .Net versions, including 1.0.  Everything in the parsed tree is one of two things: Hashtable, ArrayList or Value type (usually String).  This translates well to the YAML structure where everything is either a Map, a Set or a Value.  Taking it further Personally, I really dislike writing code like this.  Years ago, I promised myself to never write the words Hashtable or ArrayList in my .Net code again.  They are ugly, mostly depreciated collections that existed before we got generics in C# 2.0.  Now, especially that we have dynamic capabilities in C# 4.0, we can do a lot better than this.  With a relatively small amount of code, you can wrap the Hashtables and Array lists with a dynamic wrapper (wrapper code at the bottom of this post).  The same code can be re-written to look like this: dynamic doc = YamlDoc.Load("Data.yaml"); var title = doc.Recipe.Title; And dynamic doc = YamlDoc.Load("Data.yaml"); foreach (dynamic ingredient in doc.Recipe.Ingredients) { var name = ingredient.Name; } I significantly prefer this code over the previous.  That’s not all… the magic really happens when we take this concept into WPF.  With a single line of code, you can bind to the data dynamically in the view: DataContext = YamlDoc.Load("Data.yaml"); Then, your XAML is extremely straight-forward (Nothing else.  No static types, no adapter code.  Nothing): <StackPanel> <TextBlock Text="{Binding Recipe.Title}" /> <TextBlock Text="{Binding Recipe.Description}" /> <TextBlock Text="{Binding Recipe.Author}" /> <TextBlock Text="{Binding Recipe.TimeToPrepare}" /> <TextBlock Text="Ingredients:" FontWeight="Bold" /> <ItemsControl ItemsSource="{Binding Recipe.Ingredients}" Margin="10,0,0,0"> <ItemsControl.ItemTemplate> <DataTemplate> <StackPanel Orientation="Horizontal"> <TextBlock Text="{Binding Quantity}" /> <TextBlock Text=" " /> <TextBlock Text="{Binding Units}" /> <TextBlock Text=" of " /> <TextBlock Text="{Binding Name}" /> </StackPanel> </DataTemplate> </ItemsControl.ItemTemplate> </ItemsControl> <TextBlock Text="Steps:" FontWeight="Bold" /> <ItemsControl ItemsSource="{Binding Recipe.Steps}" Margin="10,0,0,0"> <ItemsControl.ItemTemplate> <DataTemplate> <StackPanel Orientation="Horizontal"> <TextBlock Text="{Binding Number}" /> <TextBlock Text=": " /> <TextBlock Text="{Binding Description}" /> </StackPanel> </DataTemplate> </ItemsControl.ItemTemplate> </ItemsControl> </StackPanel> This nifty XAML binding trick only works in WPF, unfortunately.  Silverlight handles binding differently, so they don’t support binding to dynamic objects as of late (March 2010).  This, in my opinion, is a major lacking feature in Silverlight and I really hope we will see this feature available to us in Silverlight 4 Release.  (I am not very optimistic for Silverlight 4, but I can hope for the feature in Silverlight 5, can’t I?) Conclusion I still have a few things I want to say about using YAML in the .Net space including de-serialization and using IronRuby for your YAML parser, but this post is hopefully enough to see how easy it is to incorporate YAML documents in your code. Codeplex Site for YAML tools Dynamic wrapper for YamlCore

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• Why is my external USB hard drive sometimes completely inaccessible?

  - by Eliah Kagan

  I have an external USB hard drive, consisting of an 1 TB SATA drive in a Rosewill RX35-AT-SU SLV Aluminum 3.5" Silver USB 2.0 External Enclosure, plugged into my SONY VAIO VGN-NS310F laptop. It is plugged directly into the computer (not through a hub). The drive inside the enclosure is a 7200 rpm Western Digital, but I don't remember the exact model. I can remove the drive from the enclosure (again), if people think it's necessary to know that detail. The drive is formatted ext4. I mount it dynamically with udisks on my Lubuntu 11.10 system, usually automatically via PCManFM. (I have had Lubuntu 12.04 on this machine, and experienced all this same behavior with that too.) Every once in a while--once or twice a day--it becomes inaccessible, and difficult to unmount. Attempting to unmount it with sudo umount ... gives an error message saying the drive is in use and suggesting fuser and lsof to find out what is using it. Killing processes found to be using the drive with fuser and lsof is sometimes sufficient to let me unmount it, but usually isn't. Once the drive is unmounted or the machine is rebooted, the drive will not mount. Plugging in the drive and turning it on registers nothing on the computer. dmesg is unchanged. The drive's access light usually blinks vigorously, as though the drive is being accessed constantly. Then eventually, after I keep the drive off for a while (half an hour), I am able to mount it again. While the drive doesn't work on this machine for a while, it will work immediately on another machine running the same version of Ubuntu. Sometimes bringing it back over from the other machine seems to "fix" it. Sometimes it doesn't. The drive doesn't always stop being accessible while mounted, before becoming unmountable. Sometimes it works fine, I turn off the computer, I turn the computer back on, and I cannot mount the drive. Currently this is the only drive with which I have this problem, but I've had problems that I think are the same as this, with different drives, on different Ubuntu machines. This laptop has another external USB drive plugged into it regularly, which doesn't have this problem. Unplugging that drive before plugging in the "problem" drive doesn't fix the problem. I've opened the drive up and made sure the connections were tight in the past, and that didn't seem to help (any more than waiting the same amount of time that it took to open and close the drive, before attempting to remount it). Does anyone have any ideas about what could be causing this, what troubleshooting steps I should perform, and/or how I could fix this problem altogether? Update: I tried replacing the USB data cable (from the enclosure to the laptop), as Merlin suggested. I should've tried that long ago, since it fits the symptoms perfectly (the drive works on another machine, which would make sense because the cable would be bent at a different angle, possibly completing a circuit of frayed wires). Unfortunately, though, this did not help--I have the same problem with the new cable. I'll try to provide additional detailed information about the drive inside the enclosure, next time I'm able to get the drive working. (At the moment I don't have another machine available to attach it.) Major Update (28 June 2012) The drive seems to have deteriorated considerably. I think this is so, because I've attached it to another machine and gotten lots of errors about invalid characters, when copying files from it. I am less interested in recovering data from the drive than I am in figuring out what is wrong with it. I specifically want to figure out if the problem is the drive or the enclosure. Now, when I plug the drive into the original machine where I was having the problems, it still doesn't appear (including with sudo fdisk -l), but it is recognized by the kernel and messages are added to dmesg. Most of the message consist of errors like this, repeated many times: [ 7.707593] sd 5:0:0:0: [sdc] Unhandled sense code [ 7.707599] sd 5:0:0:0: [sdc] Result: hostbyte=invalid driverbyte=DRIVER_SENSE [ 7.707606] sd 5:0:0:0: [sdc] Sense Key : Medium Error [current] [ 7.707614] sd 5:0:0:0: [sdc] Add. Sense: Unrecovered read error [ 7.707621] sd 5:0:0:0: [sdc] CDB: Read(10): 28 00 00 00 00 00 00 00 08 00 [ 7.707636] end_request: critical target error, dev sdc, sector 0 [ 7.707641] Buffer I/O error on device sdc, logical block 0 Here are all the lines from dmesg starting with when the drive is recognized. Please note that: I'm back to running Lubuntu 12.04 on this machine (and perhaps that's a factor in better error messages). Now that the drive has been plugged into another machine and back into this one, and also now that this machine is back to running 12.04, the drive's access light doesn't blink as I had described. Looking at the drive, it would appear as though it is working normally, with low or no access. This behavior (the errors) occurs when rebooting the machine with the drive plugged in, and also when manually plugging in the drive. A few of the messages are about /dev/sdb. That drive is working fine. The bad drive is /dev/sdc. I just didn't want to edit anything out from the middle.

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• The Unspoken - The Why of GC Ergonomics

  - by jonthecollector

  Do you use GC ergonomics, -XX:+UseAdaptiveSizePolicy, with the UseParallelGC collector? The jist of GC ergonomics for that collector is that it tries to grow or shrink the heap to meet a specified goal. The goals that you can choose are maximum pause time and/or throughput. Don't get too excited there. I'm speaking about UseParallelGC (the throughput collector) so there are definite limits to what pause goals can be achieved. When you say out loud "I don't care about pause times, give me the best throughput I can get" and then say to yourself "Well, maybe 10 seconds really is too long", then think about a pause time goal. By default there is no pause time goal and the throughput goal is high (98% of the time doing application work and 2% of the time doing GC work). You can get more details on this in my very first blog. GC ergonomics The UseG1GC has its own version of GC ergonomics, but I'll be talking only about the UseParallelGC version. If you use this option and wanted to know what it (GC ergonomics) was thinking, try -XX:AdaptiveSizePolicyOutputInterval=1 This will print out information every i-th GC (above i is 1) about what the GC ergonomics to trying to do. For example, UseAdaptiveSizePolicy actions to meet *** throughput goal *** GC overhead (%) Young generation: 16.10 (attempted to grow) Tenured generation: 4.67 (attempted to grow) Tenuring threshold: (attempted to decrease to balance GC costs) = 1 GC ergonomics tries to meet (in order) Pause time goal Throughput goal Minimum footprint The first line says that it's trying to meet the throughput goal. UseAdaptiveSizePolicy actions to meet *** throughput goal *** This run has the default pause time goal (i.e., no pause time goal) so it is trying to reach a 98% throughput. The lines Young generation: 16.10 (attempted to grow) Tenured generation: 4.67 (attempted to grow) say that we're currently spending about 16% of the time doing young GC's and about 5% of the time doing full GC's. These percentages are a decaying, weighted average (earlier contributions to the average are given less weight). The source code is available as part of the OpenJDK so you can take a look at it if you want the exact definition. GC ergonomics is trying to increase the throughput by growing the heap (so says the "attempted to grow"). The last line Tenuring threshold: (attempted to decrease to balance GC costs) = 1 says that the ergonomics is trying to balance the GC times between young GC's and full GC's by decreasing the tenuring threshold. During a young collection the younger objects are copied to the survivor spaces while the older objects are copied to the tenured generation. Younger and older are defined by the tenuring threshold. If the tenuring threshold hold is 4, an object that has survived fewer than 4 young collections (and has remained in the young generation by being copied to the part of the young generation called a survivor space) it is younger and copied again to a survivor space. If it has survived 4 or more young collections, it is older and gets copied to the tenured generation. A lower tenuring threshold moves objects more eagerly to the tenured generation and, conversely a higher tenuring threshold keeps copying objects between survivor spaces longer. The tenuring threshold varies dynamically with the UseParallelGC collector. That is different than our other collectors which have a static tenuring threshold. GC ergonomics tries to balance the amount of work done by the young GC's and the full GC's by varying the tenuring threshold. Want more work done in the young GC's? Keep objects longer in the survivor spaces by increasing the tenuring threshold. This is an example of the output when GC ergonomics is trying to achieve a pause time goal UseAdaptiveSizePolicy actions to meet *** pause time goal *** GC overhead (%) Young generation: 20.74 (no change) Tenured generation: 31.70 (attempted to shrink) The pause goal was set at 50 millisecs and the last GC was 0.415: [Full GC (Ergonomics) [PSYoungGen: 2048K-0K(26624K)] [ParOldGen: 26095K-9711K(28992K)] 28143K-9711K(55616K), [Metaspace: 1719K-1719K(2473K/6528K)], 0.0758940 secs] [Times: user=0.28 sys=0.00, real=0.08 secs] The full collection took about 76 millisecs so GC ergonomics wants to shrink the tenured generation to reduce that pause time. The previous young GC was 0.346: [GC (Allocation Failure) [PSYoungGen: 26624K-2048K(26624K)] 40547K-22223K(56768K), 0.0136501 secs] [Times: user=0.06 sys=0.00, real=0.02 secs] so the pause time there was about 14 millisecs so no changes are needed. If trying to meet a pause time goal, the generations are typically shrunk. With a pause time goal in play, watch the GC overhead numbers and you will usually see the cost of setting a pause time goal (i.e., throughput goes down). If the pause goal is too low, you won't achieve your pause time goal and you will spend all your time doing GC. GC ergonomics is meant to be simple because it is meant to be used by anyone. It was not meant to be mysterious and so this output was added. If you don't like what GC ergonomics is doing, you can turn it off with -XX:-UseAdaptiveSizePolicy, but be pre-warned that you have to manage the size of the generations explicitly. If UseAdaptiveSizePolicy is turned off, the heap does not grow. The size of the heap (and the generations) at the start of execution is always the size of the heap. I don't like that and tried to fix it once (with some help from an OpenJDK contributor) but it unfortunately never made it out the door. I still have hope though. Just a side note. With the default throughput goal of 98% the heap often grows to it's maximum value and stays there. Definitely reduce the throughput goal if footprint is important. Start with -XX:GCTimeRatio=4 for a more modest throughput goal (%20 of the time spent in GC). A higher value means a smaller amount of time in GC (as the throughput goal).

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• BIP and Mapviewer Mash Up I

  - by Tim Dexter

  I was out in Yellowstone last week soaking up various wildlife and a bit too much rain ... good to be back until the 95F heat yesterday. Taking a little break from the Excel templates; the dev folks are planing an Excel patch in the next week or so that will add a mass of new functionality. At the risk of completely mis leading you I'm going to hang back a while. What I have written so far holds true and will continue to do so. This week, I have been mostly eating 'mapviewer' ... answers on a post card please, TV show and character. I had a request to show how BIP can call mapviewer and render a dynamic map in an output. So I hit the books and colleagues for some answers. Mapviewer is Oracle's geographic information system, hereby known as GIS. I use it a lot in our BIEE demos where the interaction with the maps is very impressive. Need a map of California and its congressional districts? I have contacts; Jerry and David with their little black box of maps. Once in my possession I can build highly interactive, clickable maps that allow the user to drill into more information using a very friendly interface driving BIEE content and navigation. But what about maps in BIP output? Bryan Wise, who has written some articles on this blog did some work a while back with the PL/SQL API interface. The extract for the report called a function that in turn called the mapviewer server, passing a set of mapping requirements, it then returned a URL to a cached copy of that map. Easy to then have BIP render that image. Thats still very doable. You need to install a couple of packages and then load the mapviewer java APIs into the database. Then you can write your function to the APIs. A little involved? Maybe, but the database is doing all the heavy lifting for you. I thought I would investigate another method for getting the maps back into BIP. There is a URL interface you can call, this involves building an XML message to be passed to the mapviewer server. It's pretty straightforward to use on the mapviewer side. On the BIP side things are little more tricksy. After some unexpected messing about I finally got the ubiquitous Hello World map to render using the URL method. Not the most exciting map in the world, lots of ocean and a rather long URL to get it to render. http://127.0.0.1:9704/mapviewer/omserver?xml_request=%3Cmap_request%20title=%22Hello%20World%22%20datasource=%22cagis%22%20format=%22GIF_STREAM%22/%3E Notice all of the encoding in the URL string to handle the spaces, quotes, etc. All necessary to get BIP to make the call to the mapviewer server correctly without truncating the URL if it hits a real space rather than a %20. With that in mind constructing the URL was pretty simple. I'm not going to get into the content of the URL too much, for that you need to bone up on the mapviewer XML API. Check out the home page here and the documentation here. To make the template portable I used the standard CURRENT_SERVER_URL parameter from the BIP server and declared that in my template. <?param@begin:CURRENT_SERVER_URL;'myserver'?> Ignore the 'myserver', that was just a dummy value for testing at runtime it will resolve to: 'http://yourserver:port/xmlpserver' Not quite what we need as mapviewer has its own server path, in my case I needed 'mapviewer/omserver?xml_request=' as the fixed path to the mapviewer request URL. A little concatenation and substringing later I came up with <?param@begin:mURL;concat(substring($CURRENT_SERVER_URL,1,22),'mapviewer/omserver?xml_request=')?> Thats the basic URL that I can then build on. To get the Hello World map I need to add the following: <map_request title="Hello World" datasource="cagis" format="GIF_STREAM"/> Those angle brackets were the source of my headache, BIPs XSLT engine was attempting to process them rather than just pass them. Hok Min to the rescue ... again. I owe him lunch when I get out to HQ again! To solve the problem, I needed to escape all the characters and white space and then use native XSL to assign the string to a parameter. <xsl:param xdofo:ctx="begin"name="pXML">%3Cmap_request%20title=%22Hello%20World%22 %20datasource=%22cagis%22%20format=%22GIF_STREAM%22/%3E</xsl:param> I did not need to assign it to a parameter but I felt that if I were going to do anything more serious than Hello World like plotting points of interest on the map. I would need to dynamically build the URL, so using a set of parameters or variables that I then concatenated would be easier. Now I had the initial server string and the request all I then did was combine the two using a concat: concat($mURL,$pXML) Embedding that into an image tag: <fo:external-graphic src="url({concat($mURL,$pXML)})"/> and I was done. Notice the curly braces to get the concat evaluated prior to the image call. As you will see next time, building the XML message to go onto the URL can get quite complex but I have used it with some data. Ultimately, it would be easier to build an extension to BIP to handle the data to be plotted, it would then build the XML message, call mapviewer and return a URL to the map image for BIP to render. More on that next time ...

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• How to create a PeopleCode Application Package/Application Class using PeopleTools Tables

  - by Andreea Vaduva

  This article describes how - in PeopleCode (Release PeopleTools 8.50) - to enable a grid without enabling each static column, using a dynamic Application Class. The goal is to disable the following grid with three columns “Effort Date”, ”Effort Amount” and “Charge Back” , when the Check Box “Finished with task” is selected , without referencing each static column; this PeopleCode could be used dynamically with any grid. If the check box “Finished with task” is cleared, the content of the grid columns is editable (and the buttons “+” and “-“ are available): So, you create an Application Package “CLASS_EXTENSIONS” that contains an Application Class “EWK_ROWSET”. This Application Class is defined with Class extends “ Rowset” and you add two news properties “Enabled” and “Visible”: After creating this Application Class, you use it in two PeopleCode Events : Rowinit and FieldChange : This code is very ‘simple’, you write only one command : ” &ERS2.Enabled = False” → and the entire grid is “Enabled”… and you can use this code with any Grid! So, the complete PeopleCode to create the Application Package is (with explanation in [….]) : ******Package CLASS_EXTENSIONS : [Name of the Package: CLASS_EXTENSIONS] --Beginning of the declaration part------------------------------------------------------------------------------ class EWK_ROWSET extends Rowset; [Definition Class EWK_ROWSET as a subclass of Class Rowset] method EWK_ROWSET(&RS As Rowset); [Constructor is the Method with the same name of the Class] property boolean Visible get set; property boolean Enabled get set; [Definition of the property “Enabled” in read/write] private [Before the word “private”, all the declarations are publics] method SetDisplay(&DisplaySW As boolean, &PropName As string, &ChildSW As boolean); instance boolean &EnSW; instance boolean &VisSW; instance Rowset &NextChildRS; instance Row &NextRow; instance Record &NextRec; instance Field &NextFld; instance integer &RowCnt, &RecCnt, &FldCnt, &ChildRSCnt; instance integer &i, &j, &k; instance CLASS_EXTENSIONS:EWK_ROWSET &ERSChild; [For recursion] Constant &VisibleProperty = "VISIBLE"; Constant &EnabledProperty = "ENABLED"; end-class; --End of the declaration part------------------------------------------------------------------------------ method EWK_ROWSET [The Constructor] /+ &RS as Rowset +/ %Super = &RS; end-method; get Enabled /+ Returns Boolean +/; Return &EnSW; end-get; set Enabled /+ &NewValue as Boolean +/; &EnSW = &NewValue; %This.InsertEnabled=&EnSW; %This.DeleteEnabled=&EnSW; %This.SetDisplay(&EnSW, &EnabledProperty, False); [This method is called when you set this property] end-set; get Visible /+ Returns Boolean +/; Return &VisSW; end-get; set Visible /+ &NewValue as Boolean +/; &VisSW = &NewValue; %This.SetDisplay(&VisSW, &VisibleProperty, False); end-set; method SetDisplay [The most important PeopleCode Method] /+ &DisplaySW as Boolean, +/ /+ &PropName as String, +/ /+ &ChildSW as Boolean +/ [Not used in our example] &RowCnt = %This.ActiveRowCount; &NextRow = %This.GetRow(1); [To know the structure of a line ] &RecCnt = &NextRow.RecordCount; For &i = 1 To &RowCnt [Loop for each Line] &NextRow = %This.GetRow(&i); For &j = 1 To &RecCnt [Loop for each Record] &NextRec = &NextRow.GetRecord(&j); &FldCnt = &NextRec.FieldCount; For &k = 1 To &FldCnt [Loop for each Field/Record] &NextFld = &NextRec.GetField(&k); Evaluate Upper(&PropName) When = &VisibleProperty &NextFld.Visible = &DisplaySW; Break; When = &EnabledProperty; &NextFld.Enabled = &DisplaySW; [Enable each Field/Record] Break; When-Other Error "Invalid display property; Must be either VISIBLE or ENABLED" End-Evaluate; End-For; End-For; If &ChildSW = True Then [If recursion] &ChildRSCnt = &NextRow.ChildCount; For &j = 1 To &ChildRSCnt [Loop for each Rowset child] &NextChildRS = &NextRow.GetRowset(&j); &ERSChild = create CLASS_EXTENSIONS:EWK_ROWSET(&NextChildRS); &ERSChild.SetDisplay(&DisplaySW, &PropName, &ChildSW); [For each Rowset child, call Method SetDisplay with the same parameters used with the Rowset parent] End-For; End-If; End-For; end-method; ******End of the Package CLASS_EXTENSIONS:[Name of the Package: CLASS_EXTENSIONS] About the Author: Pascal Thaler joined Oracle University in 2005 where he is a Senior Instructor. His area of expertise is Oracle Peoplesoft Technology and he delivers the following courses: For Developers: PeopleTools Overview, PeopleTools I &II, Batch Application Engine, Language Oriented Object PeopleCode, Administration Security For Administrators : Server Administration & Installation, Database Upgrade & Data Management Tools For Interface Users: Integration Broker (Web Service)

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• Master Data Management Implementation Styles

  - by david.butler(at)oracle.com

  In any Master Data Management solution deployment, one of the key decisions to be made is the choice of the MDM architecture. Gartner and other analysts describe some different Hub deployment styles, which must be supported by a best of breed MDM solution in order to guarantee the success of the deployment project.   Registry Style: In a Registry Style MDM Hub, the various source systems publish their data and a subscribing Hub stores only the source system IDs, the Foreign Keys (record IDs on source systems) and the key data values needed for matching. The Hub runs the cleansing and matching algorithms and assigns unique global identifiers to the matched records, but does not send any data back to the source systems. The Registry Style MDM Hub uses data federation capabilities to build the "virtual" golden view of the master entity from the connected systems.   Consolidation Style: The Consolidation Style MDM Hub has a physically instantiated, "golden" record stored in the central Hub. The authoring of the data remains distributed across the spoke systems and the master data can be updated based on events, but is not guaranteed to be up to date. The master data in this case is usually not used for transactions, but rather supports reporting; however, it can also be used for reference operationally.   Coexistence Style: The Coexistence Style MDM Hub involves master data that's authored and stored in numerous spoke systems, but includes a physically instantiated golden record in the central Hub and harmonized master data across the application portfolio. The golden record is constructed in the same manner as in the consolidation style, and, in the operational world, Consolidation Style MDM Hubs often evolve into the Coexistence Style. The key difference is that in this architectural style the master data stored in the central MDM system is selectively published out to the subscribing spoke systems.   Transaction Style: In this architecture, the Hub stores, enhances and maintains all the relevant (master) data attributes. It becomes the authoritative source of truth and publishes this valuable information back to the respective source systems. The Hub publishes and writes back the various data elements to the source systems after the linking, cleansing, matching and enriching algorithms have done their work. Upstream, transactional applications can read master data from the MDM Hub, and, potentially, all spoke systems subscribe to updates published from the central system in a form of harmonization. The Hub needs to support merging of master records. Security and visibility policies at the data attribute level need to be supported by the Transaction Style hub, as well.   Adaptive Transaction Style: This is similar to the Transaction Style, but additionally provides the capability to respond to diverse information and process requests across the enterprise. This style emerged most recently to address the limitations of the above approaches. With the Adaptive Transaction Style, the Hub is built as a platform for consolidating data from disparate third party and internal sources and for serving unified master entity views to operational applications, analytical systems or both. This approach delivers a real-time Hub that has a reliable, persistent foundation of master reference and relationship data, along with all the history and lineage of data changes needed for audit and compliance tracking. On top of this persistent master data foundation, the Hub can dynamically aggregate transaction data on demand from different source systems to deliver the unified golden view to downstream systems. Data can also be accessed through batch interfaces, published to a message bus or served through a real-time services layer. New data sources can be readily added in this approach by extending the data model and by configuring the new source mappings and the survivorship rules, meaning that all legacy data hubs can be leveraged to contribute their records/rules into the new transaction hub. Finally, through rich user interfaces for data stewardship, it allows exception handling by business analysts to keep it current with business rules/practices while maintaining the reliability of best-of-breed master records.   Confederation Style: In this architectural style, several Hubs are maintained at departmental and/or agency and/or territorial level, and each of them are connected to the other Hubs either directly or via a central Super-Hub. Each Domain level Hub can be implemented using any of the previously described styles, but normally the Central Super-Hub is a Registry Style one. This is particularly important for Public Sector organizations, where most of the time it is practically or legally impossible to store in a single central hub all the relevant constituent information from all departments.   Oracle MDM Solutions can be deployed according to any of the above MDM architectural styles, and have been specifically designed to fully support the Transaction and Adaptive Transaction styles. Oracle MDM Solutions provide strong data federation and integration capabilities which are key to enabling the use of the Confederated Hub as a possible architectural style approach. Don't lock yourself into a solution that cannot evolve with your needs. With Oracle's support for any type of deployment architecture, its ability to leverage the outstanding capabilities of the Oracle technology stack, and its open interfaces for non-Oracle technology stacks, Oracle MDM Solutions provide a low TCO and a quick ROI by enabling a phased implementation strategy.

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• Solaris 11 Live CD alapú telepítés

  - by AndrasF

  Az elozo részben megigért két telepítési eljárás helyett kénytelen vagyok ebben a bejegyzésben kizárólag a Live CD-s változattal foglalkozni. Korábban nem gondoltam, hogy ennek bemutatása is több, mint 50 képernyo kimenetet igényel, ezért változtatnom kellett a korábbi tervezeten. A Solaris 11 Live CD-s telepítés elsosorban az asztali (desktop) felhasználók igényeit veszi figyelembe és kizárólag x86-os architektúrájú gépeken támogatott (annak ellenére, hogy SPARC-os rendszerek is rendelkeznek grafikus kártyával - pl. T4-1).A folyamat két részre bontható: eloször a vendéggép kerül kialakítása VirtualBox környezetben, majd ezt követi a Solaris 11-es telepítése virtuális gépre. HCL és segédprogramok (DDT, DDU) Mielott telepíteni szeretnénk a Solaris operációs rendszert, célszeru tájékozódni fizikai rendszerünk támogatottságáról. Erre jól használható a már említett hardver kompatibilitási (HCL) lista, vagy az alábbi két segédprogram: Device Detection Tool Device Driver Utility Mindkét alkalmazás képes rendszerünk hardver komponenseit feltérképezni és ellenorizni azok meghajtóprogram (driver) ellátottságát. Eltérés köztük abban nyilvánul meg, hogy míg a DDT futtatásához Java szükséges, addig a DDU Solarist igényel. Ez utóbbiról a telepítés során röviden szó fog esni. Telepíto készletek letöltési helye Hálózati installációtól eltekintve (*) telepítokészletre van szükségünk, mely az alábbi oldalról töltheto le. Célszeru letöltenünk mindhárom állományt és a csomagokat tartalmazó ún. repository médiát (a következo felsorolás utolsó eleme) is: sol-11-1111-live-x86.iso sol-11-1111-text-x86.iso sol-11-1111-ai-x86.iso sol-11-1111-repo-full.iso Az elso három változat indítható USB formátumban is rendelkezésre áll - ekkor iso végzodés helyett usb található a fájlnevek végén. Rövid utalást az egyes készletek feladatáról az elozo blog bejegyzés tartalmaz (link). Amennyiben SPARC architektúrájú rendszerre szeretnénk a telepítést végezni, 'x86' helyett a 'sparc' szöveget tartalmazó állományokra lesz szükség. (*) - arra is lehetoség van, hogy AI készletrol történo indítás segítségével végezzük a hálózaton keresztül történo telepítést. Ez akkor fontos, ha célgépünkön nincs PXE (Preboot Execution Environment) boot támogatás. VirtualBox konfigurálás Külön fizikai eszköz felhasználása nélkül virtuális környezetben is használható a Solaris 11, mint vendéggép. A VirtualBox használatával erre kényelmes lehetoség kínálkozik. Gazdagépünknek (Windows, Unix, Linux) megfelelo telepíto program, vagy programcsomag (jelenleg a 4.1.16-os verzió a legfrissebb változat) és az installációt is taglaló felhasználói kézikönyv letöltheto a termék oldaláról. A sikeres telepítést követoen az alábbi lépések során jutunk el az új virtuális gép kialakulásáig: 1. A VBox indítása után a központi ablak megmutatja a már létezo virtuális gépeinket (Sol11demo, Sol11u1b07, Sol11.1B16, Sun_ZFS_Storage_7000) és az aktuálisan kiválasztott egyed (Sol11demo) fobb jellemzoit (megnevezés, memória mérete, virtuális tároló eszközök listája...stb.) 2. A New gombra kattintva elindul a virtuális gépet létrehozó segéd (wizard) 3. Ezt követoen nevet kell adnunk a vendéggépnek és ki kell választanunk az operációs rendszer típusát (beszédes név használata esetén a VirtualBox képes az operációs rendszer családját kiválasztani, nekünk pusztán csak verziót kell beállítanunk): adjuk meg Solaris11-et névként és válasszuk a 64bites változatot (feltéve, hogy gazdagépünk támogatja ezt) 4. Telepítéshez és a kezdeti lépések megtételéhez 1536MB memória tökéletesen megfelel (ez késobb módosítható az elvárások függvényében) 5. Fizikai társaihoz hasonlóan, egyetlen virtuális gép sem létezhet merevlemez (jelen esetben virtuális diszk) nélkül. Használhatunk egy már létezo területet (virtuális lemezt tartalmazó állomány), de létrehozhatunk egy nekünk tetszo új példányt is. Maradjunk ez utóbbinál (Create new hard disk)! 6. A lehetséges formátumok közül - az egyszeruség okán - éljünk a felkínált alaptípussal (VDI - VirtualBox Disk Image). 7. Létrehozás során a virtuális lemez készülhet egyidejuleg (Fixed size), vagy több lépésben dinamikusan (Dynamically allocated). Az elso változat sokkal kevésbé terheli a rendszert, a második elonye pedig a helytakarékosság. Válasszuk a fix méretu változatot. 8. Most már csak egyetlen adat ismeretlen a VirtualBox számára, mégpedig a létrehozásra kerülo virtuális lemez nagysága. 8GB-os terület jelen esetben alkalmas az ismerkedés elkezdéséhez. 9. Amennyiben minden beállítást helyesen adtunk meg, a Create gomb megnyomása után elindul a virtuális lemez létrehozása. 10. Ez a muvelet a megadott adatoktól függoen néhány perc alatt befejezodik. 11. Hasonló megerosítés (Create gomb aktiválása) után elkezdodik a kért virtuális gép létrehozása is. 12. Sikeres végrehajtás után az új vitruális gép közvetlenül megjelenik a központi ablak baloldali listáján a rendelkezésre álló virtuális gépek közt. A blog bejegyzés folyamatosan frissül...a rész fennmaradó tartalma hamarosan felkerül az oldalra.

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• InnoDB Compression Improvements in MySQL 5.6

  - by Inaam Rana

  MySQL 5.6 comes with significant improvements for the compression support inside InnoDB. The enhancements that we'll talk about in this piece are also a good example of community contributions. The work on these was conceived, implemented and contributed by the engineers at Facebook. Before we plunge into the details let us familiarize ourselves with some of the key concepts surrounding InnoDB compression. In InnoDB compressed pages are fixed size. Supported sizes are 1, 2, 4, 8 and 16K. The compressed page size is specified at table creation time. InnoDB uses zlib for compression. InnoDB buffer pool will attempt to cache compressed pages like normal pages. However, whenever a page is actively used by a transaction, we'll always have the uncompressed version of the page as well i.e.: we can have a page in the buffer pool in compressed only form or in a state where we have both the compressed page and uncompressed version but we'll never have a page in uncompressed only form. On-disk we'll always only have the compressed page. When both compressed and uncompressed images are present in the buffer pool they are always kept in sync i.e.: changes are applied to both atomically. Recompression happens when changes are made to the compressed data. In order to minimize recompressions InnoDB maintains a modification log within a compressed page. This is the extra space available in the page after compression and it is used to log modifications to the compressed data thus avoiding recompressions. DELETE (and ROLLBACK of DELETE) and purge can be performed without recompressing the page. This is because the delete-mark bit and the system fields DB_TRX_ID and DB_ROLL_PTR are stored in uncompressed format on the compressed page. A record can be purged by shuffling entries in the compressed page directory. This can also be useful for updates of indexed columns, because UPDATE of a key is mapped to INSERT+DELETE+purge. A compression failure happens when we attempt to recompress a page and it does not fit in the fixed size. In such case, we first try to reorganize the page and attempt to recompress and if that fails as well then we split the page into two and recompress both pages. Now lets talk about the three major improvements that we made in MySQL 5.6.Logging of Compressed Page Images:InnoDB used to log entire compressed data on the page to the redo logs when recompression happens. This was an extra safety measure to guard against the rare case where an attempt is made to do recovery using a different zlib version from the one that was used before the crash. Because recovery is a page level operation in InnoDB we have to be sure that all recompress attempts must succeed without causing a btree page split. However, writing entire compressed data images to the redo log files not only makes the operation heavy duty but can also adversely affect flushing activity. This happens because redo space is used in a circular fashion and when we generate much more than normal redo we fill up the space much more quickly and in order to reuse the redo space we have to flush the corresponding dirty pages from the buffer pool.Starting with MySQL 5.6 a new global configuration parameter innodb_log_compressed_pages. The default value is true which is same as the current behavior. If you are sure that you are not going to attempt to recover from a crash using a different version of zlib then you should set this parameter to false. This is a dynamic parameter.Compression Level:You can now set the compression level that zlib should choose to compress the data. The global parameter is innodb_compression_level - the default value is 6 (the zlib default) and allowed values are 1 to 9. Again the parameter is dynamic i.e.: you can change it on the fly.Dynamic Padding to Reduce Compression Failures:Compression failures are expensive in terms of CPU. We go through the hoops of recompress, failure, reorganize, recompress, failure and finally page split. At the same time, how often we encounter compression failure depends largely on the compressibility of the data. In MySQL 5.6, courtesy of Facebook engineers, we have an adaptive algorithm based on per-index statistics that we gather about compression operations. The idea is that if a certain index/table is experiencing too many compression failures then we should try to pack the 16K uncompressed version of the page less densely i.e.: we let some space in the 16K page go unused in an attempt that the recompression won't end up in a failure. In other words, we dynamically keep adding 'pad' to the 16K page till we get compression failures within an agreeable range. It works the other way as well, that is we'll keep removing the pad if failure rate is fairly low. To tune the padding effort two configuration variables are exposed. innodb_compression_failure_threshold_pct: default 5, range 0 - 100,dynamic, implies the percentage of compress ops to fail before we start using to padding. Value 0 has a special meaning of disabling the padding. innodb_compression_pad_pct_max: default 50, range 0 - 75, dynamic, the  maximum percentage of uncompressed data page that can be reserved as pad.

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• How to display a dependent list box disabled if no child data exist

  - by frank.nimphius

  A requirement on OTN was to disable the dependent list box of a model driven list of value configuration whenever the list is empty. To disable the dependent list, the af:selectOneChoice component needs to be refreshed with every value change of the parent list, which however already is the case as the list boxes are already dependent. When you create model driven list of values as choice lists in an ADF Faces page, two ADF list bindings are implicitly created in the PageDef file of the page that hosts the input form. At runtime, a list binding is an instance of FacesCtrlListBinding, which exposes getItems() as a method to access a list of available child data (java.util.List). Using Expression Language, the list is accessible with #{bindings.list_attribute_name.items} To dynamically set the disabled property on the dependent af:selectOneChoice component, however, you need a managed bean that exposes the following two methods //empty – but required – setter method public void setIsEmpty(boolean isEmpty) {} //the method that returns true/false when the list is empty or //has values public boolean isIsEmpty() {   FacesContext fctx = FacesContext.getCurrentInstance();   ELContext elctx = fctx.getELContext();   ExpressionFactory exprFactory =                          fctx.getApplication().getExpressionFactory();   ValueExpression vexpr =                       exprFactory.createValueExpression(elctx,                         "#{bindings.EmployeeId.items}",                       Object.class);   List employeesList = (List) vexpr.getValue(elctx);                        return employeesList.isEmpty()? true : false;      } If referenced from the dependent choice list, as shown below, the list is disabled whenever it contains no list data <! --  master list --> <af:selectOneChoice value="#{bindings.DepartmentId.inputValue}"                                  label="#{bindings.DepartmentId.label}"                                  required="#{bindings.DepartmentId.hints.mandatory}"                                   shortDesc="#{bindings.DepartmentId.hints.tooltip}"                                   id="soc1" autoSubmit="true">      <f:selectItems value="#{bindings.DepartmentId.items}" id="si1"/> </af:selectOneChoice> <! --  dependent  list --> <af:selectOneChoice value="#{bindings.EmployeeId.inputValue}"                                   label="#{bindings.EmployeeId.label}"                                      required="#{bindings.EmployeeId.hints.mandatory}"                                   shortDesc="#{bindings.EmployeeId.hints.tooltip}"                                   id="soc2" disabled="#{lovTestbean.isEmpty}"                                   partialTriggers="soc1">     <f:selectItems value="#{bindings.EmployeeId.items}" id="si2"/> </af:selectOneChoice>

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• What Keeps You from Changing Your Public IP Address and Wreaking Havoc on the Internet?

  - by Jason Fitzpatrick

  What exactly is preventing you (or anyone else) from changing their IP address and causing all sorts of headaches for ISPs and other Internet users? Today’s Question & Answer session comes to us courtesy of SuperUser—a subdivision of Stack Exchange, a community-driven grouping of Q&A web sites. The Question SuperUser reader Whitemage is curious about what’s preventing him from wantonly changing his IP address and causing trouble: An interesting question was asked of me and I did not know what to answer. So I’ll ask here. Let’s say I subscribed to an ISP and I’m using cable internet access. The ISP gives me a public IP address of 60.61.62.63. What keeps me from changing this IP address to, let’s say, 60.61.62.75, and messing with another consumer’s internet access? For the sake of this argument, let’s say that this other IP address is also owned by the same ISP. Also, let’s assume that it’s possible for me to go into the cable modem settings and manually change the IP address. Under a business contract where you are allocated static addresses, you are also assigned a default gateway, a network address and a broadcast address. So that’s 3 addresses the ISP “loses” to you. That seems very wasteful for dynamically assigned IP addresses, which the majority of customers are. Could they simply be using static arps? ACLs? Other simple mechanisms? Two things to investigate here, why can’t we just go around changing our addresses, and is the assignment process as wasteful as it seems? The Answer SuperUser contributor Moses offers some insight: Cable modems aren’t like your home router (ie. they don’t have a web interface with simple point-and-click buttons that any kid can “hack” into). Cable modems are “looked up” and located by their MAC address by the ISP, and are typically accessed by technicians using proprietary software that only they have access to, that only runs on their servers, and therefore can’t really be stolen. Cable modems also authenticate and cross-check settings with the ISPs servers. The server has to tell the modem whether it’s settings (and location on the cable network) are valid, and simply sets it to what the ISP has it set it for (bandwidth, DHCP allocations, etc). For instance, when you tell your ISP “I would like a static IP, please.”, they allocate one to the modem through their servers, and the modem allows you to use that IP. Same with bandwidth changes, for instance. To do what you are suggesting, you would likely have to break into the servers at the ISP and change what it has set up for your modem. Could they simply be using static arps? ACLs? Other simple mechanisms? Every ISP is different, both in practice and how close they are with the larger network that is providing service to them. Depending on those factors, they could be using a combination of ACL and static ARP. It also depends on the technology in the cable network itself. The ISP I worked for used some form of ACL, but that knowledge was a little beyond my paygrade. I only got to work with the technician’s interface and do routine maintenance and service changes. What keeps me from changing this IP address to, let’s say, 60.61.62.75 and mess with another consumer’s internet access? Given the above, what keeps you from changing your IP to one that your ISP hasn’t specifically given to you is a server that is instructing your modem what it can and can’t do. Even if you somehow broke into the modem, if 60.61.62.75 is already allocated to another customer, then the server will simply tell your modem that it can’t have it. David Schwartz offers some additional insight with a link to a white paper for the really curious: Most modern ISPs (last 13 years or so) will not accept traffic from a customer connection with a source IP address they would not route to that customer were it the destination IP address. This is called “reverse path forwarding”. See BCP 38. Have something to add to the explanation? Sound off in the the comments. Want to read more answers from other tech-savvy Stack Exchange users? Check out the full discussion thread here.     

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• WebLogic JDBC Use of Oracle Wallet for SSL

  - by Steve Felts

  Introduction Secure Sockets Layer (SSL) can be used to secure the connection between the middle tier “client”, WebLogic Server (WLS) in this case, and the Oracle database server.  Data between WLS and database can be encrypted.  The server can be authenticated so you have proof that the database can be trusted by validating a certificate from the server.  The client can be authenticated so that the database only accepts connections from clients that it trusts. Similar to the discussion in an earlier article about using the Oracle wallet for database credentials, the Oracle wallet can also be used with SSL to store the keys and certificates.  By using it correctly, clear text passwords can be eliminated from the JDBC configuration and client/server configuration can be simplified by sharing the wallet across multiple datasources. There is a very good Oracle Technical White Paper on using SSL with the Oracle thin driver at http://www.oracle.com/technetwork/database/enterprise-edition/wp-oracle-jdbc-thin-ssl-130128.pdf [LINK1].  The link http://www.oracle.com/technetwork/middleware/weblogic/index-087556.html [LINK2] describes how to use WebLogic Server with Oracle JDBC Driver SSL. The information in this article is a guide on what steps need to be taken in the variety of available options; use the links above for details. SSL from the driver to the database server is basically turned on by specifying a protocol of “tcps” in the URL.  However, there is a fair amount of setup needed.  Also remember that there is an overhead in performance. Creating the wallets The common use cases are 1. “data encryption and server-only authentication”, requiring just a trust store, or 2. “data encryption and authentication of both tiers” (client and server), requiring a trust store and a key store. It is recommended to use the auto-login wallet type so that clear text passwords are not needed in the datasource configuration to open the wallet.  The store type for an auto-login wallet is “SSO” (Single Sign On), not “JKS” or “PKCS12” as in [LINK2].  The file name is “cwallet.sso”. Wallets are created using the orapki tool.  They need to be created based on the usage (encryption and/or authentication).  This is discussed in detail in [LINK1] in Appendix B or in the Advanced Security Administrator’s Guide of the Database documentation. Database Server Configuration It is necessary to update the sqlnet.ora and listener.ora files with the directory location of the wallet using WALLET_LOCATION.  These files also indicate whether or not SSL_CLIENT_AUTHENTICATION is being used (true or false). The Oracle Listener must also be configured to use the TCPS protocol.  The recommended port is 2484. LISTENER = (ADDRESS_LIST= (ADDRESS=(PROTOCOL=tcps)(HOST=servername)(PORT=2484))) WebLogic Server Classpath The WebLogic Server CLASSPATH must have three additional security files. The files that need to be added to the WLS CLASSPATH are $MW_HOME/modules/com.oracle.osdt_cert_1.0.0.0.jar $MW_HOME/modules/com.oracle.osdt_core_1.0.0.0.jar $MW_HOME/modules/com.oracle.oraclepki_1.0.0.0.jar One way to do this is to add them to PRE_CLASSPATH environment variable for use with the standard WebLogic scripts. Setting the Oracle Security Provider It’s necessary to enable the Oracle PKI provider on the client side.  This can either be done statically by updating the java.security file under the JRE or dynamically by setting it in a WLS startup class using java.security.Security.insertProviderAt(new oracle.security.pki.OraclePKIProvider (), 3); See the full example of the startup class in [LINK2]. Datasource Configuration When creating a WLS datasource, set the PROTOCOL in the URL to tcps as in the following. jdbc:oracle:thin:@(DESCRIPTION=(ADDRESS=(PROTOCOL=tcps)(HOST=host)(PORT=port))(CONNECT_DATA=(SERVICE_NAME=myservice))) For encryption and server authentication, use the datasource connection properties: - javax.net.ssl.trustStore=location of wallet file on the client - javax.net.ssl.trustStoreType=”SSO” For client authentication, use the datasource connection properties: - javax.net.ssl.keyStore=location of wallet file on the client - javax.net.ssl.keyStoreType=”SSO” Note that the driver connection properties for the wallet require a file name, not a directory name. Active GridLink ONS over SSL For completeness, there is another SSL usage for WLS datasources.  The communication with the Oracle Notification Service (ONS) for load balancing information and node up/down events can use SSL also. Create an auto-login wallet and use the wallet on the client and server.  The following is a sample sequence to create a test wallet for use with ONS. orapki wallet create -wallet ons -auto_login -pwd ONS_Wallet orapki wallet add -wallet ons -dn "CN=ons_test,C=US" -keysize 1024 -self_signed -validity 9999 -pwd ONS_Wallet orapki wallet export -wallet ons -dn "CN=ons_test,C=US" -cert ons/cert.txt -pwd ONS_Wallet On the database server side, it’s necessary to define the walletfile directory in the file $CRS_HOME/opmn/conf/ons.config and run onsctl stop/start. When configuring an Active GridLink datasource, the connection to the ONS must be defined.  In addition to the host and port, the wallet file directory must be specified.  By not giving a password, a SSO wallet is assumed. Summary To use SSL with the Oracle thin driver without any clear text passwords, use an SSO Oracle Wallet.  SSL support in the Oracle thin driver is available starting in 10g Release 2.

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• Silverlight 4 Twitter Client &ndash; Part 7

  - by Max

  Download this article as a PDF Welcome back :) This week we are going to look at something more exciting and a much required feature for any twitter client – auto refresh so as to show new status updates. We are going to achieve this using Silverlight 4 Timers and a bit and refresh our datagrid every 2 minutes to show new updates. We will do this so that we do only minimal request to the twitter api, so that twitter does not block us – there is a limit of 150 request an hour. Let us get started now. Also we will get the profile user id hyperlinked, so that when ever the user click on it, we will take them to their twitter page. Also it was a pain to always run this application by pressing F5, then it would open in a browser you would have to right click uninstall and install it again to see any changes. All this and yet we were not able to debug it :( Now there is a solution for this to run a silverlight application directly out of browser and yet have the debug feature. Super cool, here is how. Right on the Silverlight project and go to debug and then select the Out-Of-Browser application option and choose the *.Web project. Then just right click on the SL project and set as Startup Project. There you go, now every time you press F5, it will automatically run out of browser and still have the debug options. I go to know about this after some binging. Now let us jump to the core straight away. 1) To get the user id hyperlinked, we need to have a DataGridTemplateColumn and within that have a HyperLinkButton. The code for this will  be <data:DataGridTemplateColumn> <data:DataGridTemplateColumn.CellTemplate> <DataTemplate> <HyperlinkButton Click="HyperlinkButton_Click" Content="{Binding UserName}" TargetName="_blank" ></HyperlinkButton> </DataTemplate> </data:DataGridTemplateColumn.CellTemplate> </data:DataGridTemplateColumn> 2) Now let us look at how we are getting this done by looking into HyperlinkButton_Click event handler. There we will dynamically set the NavigateUri to the twitter page. I tried to do this using some binding, eval like stuff as in ASP.NET, but no luck! private void HyperlinkButton_Click(object sender, RoutedEventArgs e) { HyperlinkButton hb = (HyperlinkButton)e.OriginalSource; hb.NavigateUri = new Uri("http://twitter.com/" + hb.Content.ToString(), UriKind.Absolute); } 3) Now we need to switch on our Timer right in the OnNavigated to event on our SL page. So we need to modify our OnNavigated event to some thing like below: protected override void OnNavigatedTo(NavigationEventArgs e) { image1.Source = new BitmapImage(new Uri(GlobalVariable.profileImage, UriKind.Absolute)); this.Title = GlobalVariable.getUserName() + " - Home"; if (!GlobalVariable.isLoggedin()) this.NavigationService.Navigate(new Uri("/Login", UriKind.Relative)); else { currentGrid = "Timeline-Grid"; TwitterCredentialsSubmit(); myDispatcherTimer.Interval = new TimeSpan(0, 0, 0, 60, 0); myDispatcherTimer.Tick += new EventHandler(Each_Tick); myDispatcherTimer.Start(); } } I use a global string – here it is currentGrid variable to indicate what is bound in the datagrid so that after every timer tick, I can rebind the latest data to it again. Like I will only rebind the friends timeline again if the data grid currently holds it and I’ll only rebind the respective list status again in the data grid, if already a list status is bound to the data grid. In the above timer code, its set to trigger the Each_Tick event handler every 1 minute (60 seconds). TimeSpan takes in (days, hours, minutes, seconds, milliseconds). 4) Now we need to set the list name in the currentGrid variable when a list button is clicked. So add the code line below to the list button event handler currentGrid = currentList = b.Content.ToString(); 5) Now let us see how Each_Tick event handler is implemented. public void Each_Tick(object o, EventArgs sender) { if (!currentGrid.Equals("Timeline-Grid")) getListStatuses(currentGrid); else { WebRequest.RegisterPrefix("https://", System.Net.Browser.WebRequestCreator.ClientHttp); WebClient myService = new WebClient(); myService.AllowReadStreamBuffering = true; myService.UseDefaultCredentials = false; myService.Credentials = new NetworkCredential(GlobalVariable.getUserName(), GlobalVariable.getPassword()); myService.DownloadStringCompleted += new DownloadStringCompletedEventHandler(TimelineRequestCompleted); myService.DownloadStringAsync(new Uri("https://twitter.com/statuses/friends_timeline.xml")); } } If the data grid hold friends timeline, I just use the same bit of code we had already to bind the friends timeline to the data grid. Copy Paste. But if it is some list timeline that is bound in the datagrid, I then call the getListStatus method with the currentGrid string which will actually be holding the list name. 6) I wanted to make the hyperlinks inside the status message as hyperlinks and when the user clicks on it, we can then open that link. I tried using a convertor and using a regex to recognize a url and wrap it up with a href, but that is not gonna work in silverlight textblock :( Anyways that convertor code is in the zip file. 7) You can get the complete project files from here. 8) Please comment below for your doubts, suggestions, improvements. I will try to reply as early as possible. Thanks for all your support. Technorati Tags: Silverlight 4,Datagrid,Twitter API,Silverlight Timer

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• When is my View too smart?

  - by Kyle Burns

  In this posting, I will discuss the motivation behind keeping View code as thin as possible when using patterns such as MVC, MVVM, and MVP.  Once the motivation is identified, I will examine some ways to determine whether a View contains logic that belongs in another part of the application.  While the concepts that I will discuss are applicable to most any pattern which favors a thin View, any concrete examples that I present will center on ASP.NET MVC. Design patterns that include a Model, a View, and other components such as a Controller, ViewModel, or Presenter are not new to application development.  These patterns have, in fact, been around since the early days of building applications with graphical interfaces.  The reason that these patterns emerged is simple – the code running closest to the user tends to be littered with logic and library calls that center around implementation details of showing and manipulating user interface widgets and when this type of code is interspersed with application domain logic it becomes difficult to understand and much more difficult to adequately test.  By removing domain logic from the View, we ensure that the View has a single responsibility of drawing the screen which, in turn, makes our application easier to understand and maintain. I was recently asked to take a look at an ASP.NET MVC View because the developer reviewing it thought that it possibly had too much going on in the view.  I looked at the .CSHTML file and the first thing that occurred to me was that it began with 40 lines of code declaring member variables and performing the necessary calculations to populate these variables, which were later either output directly to the page or used to control some conditional rendering action (such as adding a class name to an HTML element or not rendering another element at all).  This exhibited both of what I consider the primary heuristics (or code smells) indicating that the View is too smart: Member variables – in general, variables in View code are an indication that the Model to which the View is being bound is not sufficient for the needs of the View and that the View has had to augment that Model.  Notable exceptions to this guideline include variables used to hold information specifically related to rendering (such as a dynamically determined CSS class name or the depth within a recursive structure for indentation purposes) and variables which are used to facilitate looping through collections while binding. Arithmetic – as with member variables, the presence of arithmetic operators within View code are an indication that the Model servicing the View is insufficient for its needs.  For example, if the Model represents a line item in a sales order, it might seem perfectly natural to “normalize” the Model by storing the quantity and unit price in the Model and multiply these within the View to show the line total.  While this does seem natural, it introduces a business rule to the View code and makes it impossible to test that the rounding of the result meets the requirement of the business without executing the View.  Within View code, arithmetic should only be used for activities such as incrementing loop counters and calculating element widths. In addition to the two characteristics of a “Smart View” that I’ve discussed already, this View also exhibited another heuristic that commonly indicates to me the need to refactor a View and make it a bit less smart.  That characteristic is the existence of Boolean logic that either does not work directly with properties of the Model or works with too many properties of the Model.  Consider the following code and consider how logic that does not work directly with properties of the Model is just another form of the “member variable” heuristic covered earlier: @if(DateTime.Now.Hour < 12) {     <div>Good Morning!</div> } else {     <div>Greetings</div> } This code performs business logic to determine whether it is morning.  A possible refactoring would be to add an IsMorning property to the Model, but in this particular case there is enough similarity between the branches that the entire branching structure could be collapsed by adding a Greeting property to the Model and using it similarly to the following: <div>@Model.Greeting</div> Now let’s look at some complex logic around multiple Model properties: @if (ModelPageNumber + Model.NumbersToDisplay == Model.PageCount         || (Model.PageCount != Model.CurrentPage             && !Model.DisplayValues.Contains(Model.PageCount))) {     <div>There's more to see!</div> } In this scenario, not only is the View code difficult to read (you shouldn’t have to play “human compiler” to determine the purpose of the code), but it also complex enough to be at risk for logical errors that cannot be detected without executing the View.  Conditional logic that requires more than a single logical operator should be looked at more closely to determine whether the condition should be evaluated elsewhere and exposed as a single property of the Model.  Moving the logic above outside of the View and exposing a new Model property would simplify the View code to: @if(Model.HasMoreToSee) {     <div>There’s more to see!</div> } In this posting I have briefly discussed some of the more prominent heuristics that indicate a need to push code from the View into other pieces of the application.  You should now be able to recognize these symptoms when building or maintaining Views (or the Models that support them) in your applications.

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• Silverlight Reporting Application Part 3.5 - Prism Background and WCF RIA [Series Intermission]

  Taking a step back before I dive into the details and full-on coding fun, I wanted to once again respond to a comment on my last post to clear up some things in regards to how I'm setting up my project and some of the choices I've made. Aka, thanks Ben. :) Prism Project Setup For starters, I'm not the ideal use case for a Prism application. In most cases where you've got a one-man team, Prism can be overkill as it is more intended for large teams who are geographically dispersed or in applications that have a larger scale than my Recruiting application in which you'll greatly benefit from modularity, delayed loading of xaps, etc. What Prism offers, though, is a manner for handling UI, commands, and events with the idea that, through a modular approach in which no parts really need to know about one another, I can update this application bit by bit as hiring needs change or requirements differ between offices without having to worry that changing something in the Jobs module will break something in, say, the Scheduling module. All that being said, here's a look at how our project breakdown for Recruit (MVVM/Prism implementation) looks: This could be a little misleading though, as each of those modules is actually another project in the overall Recruit solution. As far as what the projects actually are, that looks a bit like this: Recruiting Solution Recruit (Shell up there) - Main Silverlight Application .Web - Default .Web application to host the Silverlight app Infrastructure - Silverlight Class Library Project Modules - Silverlight Class Library Projects Infrastructure &Modules The Infrastructure project is probably something you'll see to some degree in any composite application. In this application, it is going to contain custom commands (you'll see the joy of these in a post or two down the road), events, helper classes, and any custom classes I need to share between different modules. Think of this as a handy little crossroad between any parts of your application. Modules on the other hand are the bread and butter of this application. Besides the shell, which holds the UI skeleton, and the infrastructure, which holds all those shared goodies, the modules are self-contained bundles of functionality to handle different concerns. In my scenario, I need a way to look up and edit Jobs, Applicants, and Schedule interviews, a Notification module to handle telling the user when different things are happening (i.e., loading from database), and a Menu to control interaction and moving between different views. All modules are going to follow the following pattern: The module class will inherit from IModule and handle initialization and loading the correct view into the correct region, whereas the Views and ViewModels folders will contain paired Silverlight user controls and ViewModel class backings. WCF RIA Services Since we've got all the projects in a single solution, we did not have to go the route of creating a WCR RIA Services Class Library. Every module has it's WCF RIA link back to the main .Web project, so the single Linq-2-SQL (yes, I said Linq-2-SQL, but I'll soon be switching to OpenAccess due to the new visual designer) context I'm using there works nicely with the scope of my project. If I were going for completely separating this project out and doing different, dynamically loaded elements, I'd probably go for the separate class library. Hope that clears that up. In the future though, I will be using that in a project that I've got in the "when I've got enough time to work on this" pipeline, so we'll get into that eventually- and hopefully when WCF RIA is in full release! Why Not use Silverlight Navigation/Business Template? The short answer- I'm a creature of habit, and having used Silverlight for a few years now, I'm used to doing lots of things manually. :) Plus, starting with a blank slate of a project I'm able to set up things exactly as I want them to be. In this case, rather than the navigation frame we would see in one of the templates, the MainRegion/ContentControl is working as our main navigation window. In many cases I will use theSilverlight navigation template to start things off, however in this case I did not need those features so I opted out of using that. Next time when I actually hit post #4, we're going to get into the modules and starting to get functionality into this application. Next week is also release week for the Q1 2010 release, so be sure to check out our annualWebinar Week (I might be biased, but Wednesday is my favorite out of the group). Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• How-to populate different select list content per table row

  - by frank.nimphius

  Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} A frequent requirement posted on the OTN forum is to render cells of a table column using instances of af:selectOneChoices with each af:selectOneChoice instance showing different list values. To implement this use case, the select list of the table column is populated dynamically from a managed bean for each row. The table's current rendered row object is accessible in the managed bean using the #{row} expression, where "row" is the value added to the table's var property. <af:table var="row">   ...   <af:column ...>     <af:selectOneChoice ...>         <f:selectItems value="#{browseBean.items}"/>     </af:selectOneChoice>   </af:column </af:table> The browseBean managed bean referenced in the code snippet above has a setItems and getItems method defined that is accessible from EL using the #{browseBean.items} expression. When the table renders, then the var property variable - the #{row} reference - is filled with the data object displayed in the current rendered table row. The managed bean getItems method returns a List<SelectItem>, which is the model format expected by the f:selectItems tag to populate the af:selectOneChoice list. public void setItems(ArrayList<SelectItem> items) {} //this method is executed for each table row public ArrayList<SelectItem> getItems() {   FacesContext fctx = FacesContext.getCurrentInstance();   ELContext elctx = fctx.getELContext();   ExpressionFactory efactory =          fctx.getApplication().getExpressionFactory();          ValueExpression ve =          efactory.createValueExpression(elctx, "#{row}", Object.class);      Row rw = (Row) ve.getValue(elctx);         //use one of the row attributes to determine which list to query and   //show in the current af:selectOneChoice list  // ...  ArrayList<SelectItem> alsi = new ArrayList<SelectItem>();  for( ... ){      SelectItem item = new SelectItem();        item.setLabel(...);        item.setValue(...);        alsi.add(item);   }   return alsi;} For better performance, the ADF Faces table stamps it data rows. Stamping means that the cell renderer component - af:selectOneChoice in this example - is instantiated once for the column and then repeatedly used to display the cell data for individual table rows. This however means that you cannot refresh a single select one choice component in a table to change its list values. Instead the whole table needs to be refreshed, rerunning the managed bean list query. Be aware that having individual list values per table row is an expensive operation that should be used only on small tables for Business Services with low latency data fetching (e.g. ADF Business Components and EJB) and with server side caching strategies for the queried data (e.g. storing queried list data in a managed bean in session scope).

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• A Patent for Workload Management Based on Service Level Objectives

  - by jsavit

  I'm very pleased to announce that after a tiny :-) wait of about 5 years, my patent application for a workload manager was finally approved. Background Many operating systems have a resource manager which lets you control machine resources. For example, Solaris provides controls for CPU with several options: shares for proportional CPU allocation. If you have twice as many shares as me, and we are competing for CPU, you'll get about twice as many CPU cycles), dedicated CPU allocation in which a number of CPUs are exclusively dedicated to an application's use. You can say that a zone or project "owns" 8 CPUs on a 32 CPU machine, for example. And, capped CPU in which you specify the upper bound, or cap, of how much CPU an application gets. For example, you can throttle an application to 0.125 of a CPU. (This isn't meant to be an exhaustive list of Solaris RM controls.) Workload management Useful as that is (and tragic that some other operating systems have little resource management and isolation, and frighten people into running only 1 app per OS instance - and wastefully size every server for the peak workload it might experience) that's not really workload management. With resource management one controls the resources, and hope that's enough to meet application service objectives. In fact, we hold resource distribution constant, see if that was good enough, and adjust resource distribution if that didn't meet service level objectives. Here's an example of what happens today: Let's try 30% dedicated CPU. Not enough? Let's try 80% Oh, that's too much, and we're achieving much better response time than the objective, but other workloads are starving. Let's back that off and try again. It's not the process I object to - it's that we to often do this manually. Worse, we sometimes identify and adjust the wrong resource and fiddle with that to no useful result. Back in my days as a customer managing large systems, one of my users would call me up to beg for a "CPU boost": Me: "it won't make any difference - there's plenty of spare CPU to be had, and your application is completely I/O bound." User: "Please do it anyway." Me: "oh, all right, but it won't do you any good." (I did, because he was a friend, but it didn't help.) Prior art There are some operating environments that take a stab about workload management (rather than resource management) but I find them lacking. I know of one that uses synthetic "service units" composed of the sum of CPU, I/O and memory allocations multiplied by weighting factors. A workload is set to make a target rate of service units consumed per second. But this seems to be missing a key point: what is the relationship between artificial 'service units' and actually meeting a throughput or response time objective? What if I get plenty of one of the components (so am getting enough service units), but not enough of the resource whose needed to remove the bottleneck? Actual workload management That's not really the answer either. What is needed is to specify a workload's service levels in terms of externally visible metrics that are meaningful to a business, such as response times or transactions per second, and have the workload manager figure out which resources are not being adequately provided, and then adjust it as needed. If an application is not meeting its service level objectives and the reason is that it's not getting enough CPU cycles, adjust its CPU resource accordingly. If the reason is that the application isn't getting enough RAM to keep its working set in memory, then adjust its RAM assignment appropriately so it stops swapping. Simple idea, but that's a task we keep dumping on system administrators. In other words - don't hold the number of CPU shares constant and watch the achievement of service level vary. Instead, hold the service level constant, and dynamically adjust the number of CPU shares (or amount of other resources like RAM or I/O bandwidth) in order to meet the objective. Instrumenting non-instrumented applications There's one little problem here: how do I measure application performance in a way relating to a service level. I don't want to do it based on internal resources like number of CPU seconds it received per minute - We need to make resource decisions based on externally visible and meaningful measures of performance, not synthetic items or internal resource counters. If I have a way of marking the beginning and end of a transaction, I can then measure whether or not the application is meeting an objective based on it. If I can observe the delay factors for an application, I can see which resource shortages are slowing an application enough to keep it from meeting its objectives. I can then adjust resource allocations to relieve those shortages. Fortunately, Solaris provides facilities for both marking application progress and determining what factors cause application latency. The Solaris DTrace facility let's me introspect on application behavior: in particular I can see events like "receive a web hit" and "respond to that web hit" so I can get transaction rate and response time. DTrace (and tools like prstat) let me see where latency is being added to an application, so I know which resource to adjust. Summary After a delay of a mere few years, I am the proud creator of a patent (advice to anyone interested in going through the process: don't hold your breath!). The fundamental idea is fairly simple: instead of holding resource constant and suffering variable levels of success meeting service level objectives, properly characterise the service level objective in meaningful terms, instrument the application to see if it's meeting the objective, and then have a workload manager change resource allocations to remove delays preventing service level attainment. I've done it by hand for a long time - I think that's what a computer should do for me.

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• CPU Usage in Very Large Coherence Clusters

  - by jpurdy

  When sizing Coherence installations, one of the complicating factors is that these installations (by their very nature) tend to be application-specific, with some being large, memory-intensive caches, with others acting as I/O-intensive transaction-processing platforms, and still others performing CPU-intensive calculations across the data grid. Regardless of the primary resource requirements, Coherence sizing calculations are inherently empirical, in that there are so many permutations that a simple spreadsheet approach to sizing is rarely optimal (though it can provide a good starting estimate). So we typically recommend measuring actual resource usage (primarily CPU cycles, network bandwidth and memory) at a given load, and then extrapolating from those measurements. Of course there may be multiple types of load, and these may have varying degrees of correlation -- for example, an increased request rate may drive up the number of objects "pinned" in memory at any point, but the increase may be less than linear if those objects are naturally shared by concurrent requests. But for most reasonably-designed applications, a linear resource model will be reasonably accurate for most levels of scale. However, at extreme scale, sizing becomes a bit more complicated as certain cluster management operations -- while very infrequent -- become increasingly critical. This is because certain operations do not naturally tend to scale out. In a small cluster, sizing is primarily driven by the request rate, required cache size, or other application-driven metrics. In larger clusters (e.g. those with hundreds of cluster members), certain infrastructure tasks become intensive, in particular those related to members joining and leaving the cluster, such as introducing new cluster members to the rest of the cluster, or publishing the location of partitions during rebalancing. These tasks have a strong tendency to require all updates to be routed via a single member for the sake of cluster stability and data integrity. Fortunately that member is dynamically assigned in Coherence, so it is not a single point of failure, but it may still become a single point of bottleneck (until the cluster finishes its reconfiguration, at which point this member will have a similar load to the rest of the members). The most common cause of scaling issues in large clusters is disabling multicast (by configuring well-known addresses, aka WKA). This obviously impacts network usage, but it also has a large impact on CPU usage, primarily since the senior member must directly communicate certain messages with every other cluster member, and this communication requires significant CPU time. In particular, the need to notify the rest of the cluster about membership changes and corresponding partition reassignments adds stress to the senior member. Given that portions of the network stack may tend to be single-threaded (both in Coherence and the underlying OS), this may be even more problematic on servers with poor single-threaded performance. As a result of this, some extremely large clusters may be configured with a smaller number of partitions than ideal. This results in the size of each partition being increased. When a cache server fails, the other servers will use their fractional backups to recover the state of that server (and take over responsibility for their backed-up portion of that state). The finest granularity of this recovery is a single partition, and the single service thread can not accept new requests during this recovery. Ordinarily, recovery is practically instantaneous (it is roughly equivalent to the time required to iterate over a set of backup backing map entries and move them to the primary backing map in the same JVM). But certain factors can increase this duration drastically (to several seconds): large partitions, sufficiently slow single-threaded CPU performance, many or expensive indexes to rebuild, etc. The solution of course is to mitigate each of those factors but in many cases this may be challenging. Larger clusters also lead to the temptation to place more load on the available hardware resources, spreading CPU resources thin. As an example, while we've long been aware of how garbage collection can cause significant pauses, it usually isn't viewed as a major consumer of CPU (in terms of overall system throughput). Typically, the use of a concurrent collector allows greater responsiveness by minimizing pause times, at the cost of reducing system throughput. However, at a recent engagement, we were forced to turn off the concurrent collector and use a traditional parallel "stop the world" collector to reduce CPU usage to an acceptable level. In summary, there are some less obvious factors that may result in excessive CPU consumption in a larger cluster, so it is even more critical to test at full scale, even though allocating sufficient hardware may often be much more difficult for these large clusters.

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• Web Services Example - Part 2: Programmatic

  - by Denis T

  In this edition of the ADF Mobile blog we'll tackle part 2 of our Web Service examples.  In this posting we'll take a look at using a SOAP Web Service but calling it programmatically in code and parsing the return into a bean. Getting the sample code: Just click here to download a zip of the entire project.  You can unzip it and load it into JDeveloper and deploy it either to iOS or Android.  Please follow the previous blog posts if you need help getting JDeveloper or ADF Mobile installed.  Note: This is a different workspace than WS-Part1 Defining our Web Service: Just like our first installment, we are using the same public weather forecast web service provided free by CDYNE Corporation.  Sometimes this service goes down so please ensure you know it's up before reporting this example isn't working. We're going to concentrate on the same two web service methods, GetCityForecastByZIP and GetWeatherInformation. Defing the Application: The application setup is identical to the Weather1 version.  There are some improvements to the data that is displayed as part of this example though.  Now we are able to show the associated image along with each forecast line when using the Forecast By Zip feature.  We've also added the temperature Hi/Low values into the UI. Summary of Fundamental Changes In This Application The most fundamental change is that we're binding the UI to the Bean Data Controls instead of directly to the Web Service Data Controls.  This gives us much more flexibility to control the shape of the data and allows us to do caching of the data outside of the Web Service.  This way if your application is, say offline, your bean could still populate with data from a local cache and still show you some UI as opposed to completely failing because you don't have any connectivity. In general we promote this type of programming technique with ADF Mobile to insulate your application from any issues with network connectivity. What's different with this example? We have setup the Web Service DC the same way but now we have managed beans to process the data.  The following classes define the "Model" of our application:  CityInformation-CityForecast-Forecast, WeatherInformation-WeatherDescription.  We use WeatherBean for UI interaction to the model layer.  If you look through this example, we don't really do that much with the java code except use it to grab the image URL from the weather description.  In a more realistic example, you might be using some JDBC classes to persist the data to a local database. To have a good architecture it is always good to keep your model and UI layers separate.  This gets muddied if you start to use bindings on a page invoked from Java code and this java code starts to become your "model" layer.  Since bindings are page specific, your model layer starts to become entwined with your UI.  Not good!  To help with this, we've added some utility functions that let you invoke DC methods without having a binding and thus execute methods from your "model" layer without requiring a binding in your page definition.  We do this with the invokeDataControlMethod of the AdfmfJavaUtilities class.  An example of this method call is available in line 95 of WeatherInformation.java and line 93 of CityInformation.Java. What's a GenericType? Because Web Service Data Controls (and also URL Data Controls AKA REST) use generic name/value pairs to define their structure and don't have strongly typed objects, these are actually stored internally as GenericType objects.  The GenericType class is simply a property map of name/value pairs that can be hierarchical.  There are methods like getAttribute where you supply the index of the attribute or it's string property name.  Why is this important to know?  Because invokeDataControlMethod returns GenericType objects and developers either need to parse these GenericType objects themselves or use one of our helper functions. GenericTypeBeanSerializationHelper This class does exactly what it's name implies.  It's a helper class for developers to aid in serialization of GenericTypes to/from java objects.  This is extremely handy if you have a large GenericType object with many attributes (or you're just lazy like me!) and you just want to parse it out into a real java object you can use more easily.  Here you would use the fromGenericType method.  This method takes the class of the Java object you wish to return and the GenericType as parameters.  The method then parses through each attribute in the GenericType and uses reflection to set that same attribute in the Java class.  Then the method returns that new object of the class you specified.  This is obviously very handy to avoid a lot of shuffling code between GenericType and your own Java classes.  The reverse method, toGenericType is also available when you want to go the other way.  In this case you supply the string that represents the package location in the DataControl definition (Example: "MyDC.myParams.MyCollection") and then pass in the Java object you have that holds the data and a GenericType is returned to you.  Again, it will use reflection to calculate the attributes that match between the java class and the GenericType and call the getters/setters on those. Issues and Possible Improvements: In the next installment we'll show you how to make your web service calls asynchronously so your UI will fill dynamically when the service call returns but in the meantime you show the data you have locally in your bean fed from some local cache.  This gives your users instant delivery of some data while you fetch other data in the background.

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• Eloqua Experience 2013: Mystique, Modern Marketing and Masterful Engagement

  - by Mike Stiles

  The following is a guest post from Erick Mott, a social business leader at Oracle Eloqua. There’s a growing gap between 20th century marketing and a modern marketing way of doing business. I can’t think of a better example of modern marketing in action than what more than 2,000 people experienced in San Francisco at #EE13; customer-obsession, multichannel content, and real-time engagement all coming together at one extraordinary event. This was my first Eloqua Experience as a new Oracle Eloqua employee. In weeks prior, I heard about the mystique but didn’t know what to expect. What I’ve come to understand with more clarity is everything we do revolves around customer success, and we operate and educate at all times with these five tenets in mind: 1. Targeting: Really Know Your Buyer 2. Engagement: Create a 1:1 Relationship 3. Conversion: Visualize Guided Thinking 4. Analysis: Learn What’s Working 5. Marketing Technology: Enable and Extend the Cloud Product News from Eloqua Experience 2013 We made some announcements that John Stetic, VP of Products, Oracle Eloqua covers in this brief ‘Modern Marketing Minute’ video recorded after Wednesday’s keynote; summarized below, too: Oracle Eloqua AdFocus: While understanding the impact of a specific marketing channel was formerly relegated to marketers’ wish lists, the channels we now focus on are digital, social, and mobile. AdFocus gives marketers a single platform to dynamically create, manage and measure display ads alongside owned and earned media. AdFocus enables marketers to target only key accounts or prospects you want to reach with display ads, as well as provide creative content or personalized ad copy based on their persona and activities. Oracle Eloqua Profiler: The details of what we now know about customers have expanded into a universal customer profile, which can be used to create highly targeted segments. Marketers now can take data that’s not even stored in Eloqua to help targeted and score prospects for a complete, multichannel view of the customer. Profiler gives sales reps one, detailed view of the prospect to extend views beyond Oracle Eloqua asset activity (emails, forms, page views) to any external assets stored in Oracle Eloqua. Marketing Resource Management: New capabilities create more secure and controlled access to marketing resources and data. New integrations provide greater insight into campaign resources and management through a central marketing calendar and simplify resource management. Integrated Sales and Marketing Funnel: An integrated sales and marketing funnel view gives marketing and sales users, cross-functional teams, and executive management a consistent and clear view of pipeline performance. It also quickly provides users with historical metrics across different time spans and conditions. Eloqua AppCloud: More than 20 new AppCloud partners have been added to the community, which now includes 100+ apps. Eloqua AppCloud now provides modern marketers with an even broader range of marketing applications that help expand and enrich sales and marketing efforts; easily accessible in the Topliners Community. Social Capabilities: Recent integration between Oracle Eloqua and Oracle Social Relationship Management (SRM) deliver a comprehensive, scalable and integrated modern marketing solution. New capabilities include better tracking of social activities for a more complete customer profile. Engage Facebook custom audiences with AdFocus to deliver ads and meaningful experiences through trusted social networks. Biggest and Best Eloqua Experience. There’s a lot of talk in the industry about the Marketing Cloud. At Oracle Eloqua, we have been on a mission of delivering the most advanced and integrated modern marketing technology on the planet. It’s not just a concept but reality with proven execution, as seen first-hand this week in San Francisco. In this video, Kevin Akeroyd, SVP of Oracle Eloqua, provides some highlights of what made this year’s Eloqua Experience, exceptional, including Steve Woods’ presentation about the journey of modern marketers and Andrea Ward’s conversation with Vince Gilligan, creator of the Breaking Bad television series. The 2013 Markie Awards The Oracle Eloqua Marketing Cloud was best exemplified for me as 19 Markies were awarded to customers for their exceptional creativity and results as modern marketers. Wow, what a night to remember with so many committed and talented people working to create an extraordinary experience! To learn more about how to become a modern marketer, check out these resources. We look forward to seeing you next year at Eloqua Experience. More on Erick: 20 years experience at Oracle, Ektron, Sitecore, Lyris, Habeas, Nokia, creatorbase, Mark Monitor, Cisco Systems, GlobalFluency, Sun Microsystems, Philips NV, Elm Products and CBS TV. Patent holder with agency, Fortune 500, media, and startup company expertise. @mikestiles

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• YouTube SEO: Video Optimization

  - by Mike Stiles

  SEO optimization is still regarded as one of the primary tools in the digital marketing kit. However and wherever a potential customer is conducting a search, brands want their content to surface in the top results. Makes sense. But without a regular flow of good, relevant content, your SEO opportunities run shallow. We know from several studies video is one of the most engaging forms of content, so why not make sure that in addition to being cool, your videos are helping you win the SEO game? Keywords:-Decide what search phrases make the most sense for your video. Don’t dare use phrases that have nothing to do with the content. You’ll make people mad.-Research those keywords to see how competitive they are. Adjust them so there are still lots of people searching for it, but there are not as many links showing up for it.-Search your potential keywords and phrases to see what comes up. It’s amazing how many people forget to do that. Video Title: -Try to start and/or end with your keyword.-When you search on YouTube, visual action words tend to come up as suggested searches. So try to use action words. Video Description: -Lead with a link to your site (include http://). -Don’t stuff this with your keyword. It leads to bad writing and it won’t work anyway. This is where you convince people to watch, so write for humans. Use some showmanship. -At the end, do a call to action (subscribe, see the whole playlist, visit our social channels, etc.) Video Tags:-Don’t over-tag. 5-10 tags per video is plenty. -If you’re compelled to have more than 10, that means you should probably make more videos specifically targeting all those keywords. Find Linking Pals:-45% of videos are discovered on video sites. But 44% are found through links on blogs and sites.-Write a blog about your video’s content, then link to the video in it. -A good site for finding places to guest blog is myblogguest.com-Once you find good linking partners, they’ll link to your future videos (as long as they’re good and you’re returning the favor). Tap the Power of Similar Videos:-Use Video Reply to associate your video with other topic-related videos. That’s when you make a video responding to or referencing a video made by someone else. Content:-Again, build up a portfolio of videos, not just one that goes after 30 keywords.-Create shorter, sequential videos that pull them deeper into the content and closer to a desired final action.-Organize your video topics separately using Playlists. Playlists show up as a whole in search results like individual videos, so optimize playlists the same as you would for a video. Meta Data:-Too much importance is placed on it. It accounts for only 15% of search success.-YouTube reads Captions or Transcripts to determine what a video is about. If you’re not using them, you’re missing out.-You get the SEO benefit of captions and transcripts whether the viewers has them toggled on or not. Promotion:-This accounts for 25% of search success.-Promote the daylights out of your videos using your social channels and digital assets. Don’t assume it’s going to magically get discovered. -You can pay to promote your video. This could surface it on the YouTube home page, YouTube search results, YouTube related videos, and across the Google content network. Community:-Accounts for 10% of search success.-Make sure your YouTube home page is a fun place to spend time. Carefully pick your featured video, and make sure your Playlists are featured. -Participate in discussions so users will see you’re present. The volume of ratings/comments is as important as the number of views when it comes to where you surface on search. Video Sitemaps:-As with a web site, a video sitemap helps Google quickly index your video.-Google wants to know title, description, play page URL, the URL of the thumbnail image you want, and raw video file location.-Sitemaps are xml files you host or dynamically generate on your site. Once you’ve made your sitemap, sign in and submit it using Google webmaster tools. Just as with the broadcast and cable TV channels, putting a video out there is only step one. You also have to make sure everybody knows it’s there so the largest audience possible can see it. Here’s hoping you get great ratings. @mikestiles

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