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  • Getting Started with jqChart for ASP.NET Web Forms

    - by jqChart
    Official Site | Samples | Download | Documentation | Forum | Twitter Introduction jqChart takes advantages of HTML5 Canvas to deliver high performance client-side charts and graphs across browsers (IE 6+, Firefox, Chrome, Opera, Safari) and devices, including iOS and Android mobile devices. Some of the key features are: High performance rendering. Animaitons. Scrolling/Zoooming. Support for unlimited number of data series and data points. Support for unlimited number of chart axes. True DateTime Axis. Logarithmic and Reversed axis scale. Large set of chart types - Bar, Column, Pie, Line, Spline, Area, Scatter, Bubble, Radar, Polar. Financial Charts - Stock Chart and Candlestick Chart. The different chart types can be easily combined.  System Requirements Browser Support jqChart supports all major browsers: Internet Explorer - 6+ Firefox Google Chrome Opera Safari jQuery version support jQuery JavaScript framework is required. We recommend using the latest official stable version of the jQuery library. Visual Studio Support jqChart for ASP.NET does not require using Visual Studio. You can use your favourite code editor. Still, the product has been tested with several versions of Visual Studio .NET and you can find the list of supported versions below: Visual Studio 2008 Visual Studio 2010 Visual Studio 2012 ASP.NET Web Forms support Supported version - ASP.NET Web Forms 3.5, 4.0 and 4.5 Installation Download and unzip the contents of the archive to any convenient location. The package contains the following folders: [bin] - Contains the assembly DLLs of the product (JQChart.Web.dll) for WebForms 3.5, 4.0 and 4.5. This is the assembly that you can reference directly in your web project (or better yet, add it to your ToolBox and then drag & drop it from there). [js] - The javascript files of jqChart and jqRangeSlider (and the needed libraries). You need to include them in your ASPX page, in order to gain the client side functionality of the chart. The first file is "jquery-1.5.1.min.js" - this is the official jQuery library. jqChart is built upon jQuery library version 1.4.3. The second file you need is the "excanvas.js" javascript file. It is used from the versions of IE, which dosn't support canvas graphics. The third is the jqChart javascript code itself, located in "jquery.jqChart.min.js". The last one is the jqRangeSlider javascript, located in "jquery.jqRangeSlider.min.js". It is used when the chart zooming is enabled. [css] - Contains the Css files that the jqChart and the jqRangeSlider need. [samples] - Contains some examples that use the jqChart. For full list of samples plese visit - jqChart for ASP.NET Samples. [themes] - Contains the themes shipped with the products. It is used from the jqRangeSlider. Since jqRangeSlider supports jQuery UI Themeroller, any theme compatible with jQuery UI ThemeRoller will work for jqRangeSlider as well. You can download any additional themes directly from jQuery UI's ThemeRoller site available here: http://jqueryui.com/themeroller/ or reference them from Microsoft's / Google's CDN. <link rel="stylesheet" type="text/css" media="screen" href="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.8.21/themes/smoothness/jquery-ui.css" /> The final result you will have in an ASPX page containing jqChart would be something similar to that (assuming you have copied the [js] to the Script folder and [css] to Content folder of your ASP.NET site respectively). <%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="samples_cs.Default" %> <%@ Register Assembly="JQChart.Web" Namespace="JQChart.Web.UI.WebControls" TagPrefix="jqChart" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html > <head runat="server"> <title>jqChart ASP.NET Sample</title> <link rel="stylesheet" type="text/css" href="~/Content/jquery.jqChart.css" /> <link rel="stylesheet" type="text/css" href="~/Content/jquery.jqRangeSlider.css" /> <link rel="stylesheet" type="text/css" href="~/Content/themes/smoothness/jquery-ui-1.8.21.css" /> <script src="<% = ResolveUrl("~/Scripts/jquery-1.5.1.min.js") %>" type="text/javascript"></script> <script src="<% = ResolveUrl("~/Scripts/jquery.jqRangeSlider.min.js") %>" type="text/javascript"></script> <script src="<% = ResolveUrl("~/Scripts/jquery.jqChart.min.js") %>" type="text/javascript"></script> <!--[if IE]><script lang="javascript" type="text/javascript" src="<% = ResolveUrl("~/Scripts/excanvas.js") %>"></script><![endif]--> </head> <body> <form id="form1" runat="server"> <asp:ObjectDataSource ID="ObjectDataSource1" runat="server" SelectMethod="GetData" TypeName="SamplesBrowser.Models.ChartData"></asp:ObjectDataSource> <jqChart:Chart ID="Chart1" Width="500px" Height="300px" runat="server" DataSourceID="ObjectDataSource1"> <Title Text="Chart Title"></Title> <Animation Enabled="True" Duration="00:00:01" /> <Axes> <jqChart:CategoryAxis Location="Bottom" ZoomEnabled="true"> </jqChart:CategoryAxis> </Axes> <Series> <jqChart:ColumnSeries XValuesField="Label" YValuesField="Value1" Title="Column"> </jqChart:ColumnSeries> <jqChart:LineSeries XValuesField="Label" YValuesField="Value2" Title="Line"> </jqChart:LineSeries> </Series> </jqChart:Chart> </form> </body> </html>   Official Site | Samples | Download | Documentation | Forum | Twitter

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  • Web Seminar - The Oracle Database Appliance: How to Sell a Unique Product!

    - by swalker
    Dear partner, You are exclusively invited to join us for a webcast, dedicated to Oracle’s EMEA Partners, on the Oracle Database Appliance value proposition, positioning and ecosystem – to help you capture new business and help your customers roll out their solutions fast, easily, safely and with maximum cost efficiency! Join us to learn about: ODA Benefits: Fast, Easy, Cost Efficient, Highly Reliable Feedback from early Customer Wins: What can we Learn? Objection Handling: Overcoming the most common customer questions Going beyond the Database: The ODA ECO System for applications, backup & more… When combined with your high-value services (e.g., migration, consolidation), the end result is a database system that you can use to grow the business in your existing accounts, or capture new business. Join us at the EMEA partner webcast hosted by Robert Van Espelo Cloud and Virtualization Leader, EMEA Business Development on Thursday, April 12, at 9:00am UK / 10:00am CET. The presentation will be given in English. To register for this webcast click here We look forward to talking to you on April 12! Best regards,Giuseppe Facchetti EMEA Partner Business Development Manager Oracle EMEA, Hardware Sales Paul LeonardEMEA Partner Marketing Manager Oracle EMEA, Systems Marketing

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  • Taking HRMS to the Cloud to Simplify Human Resources Management

    - by HCM-Oracle
    By Anke Mogannam With human capital management (HCM) a top-of-mind issue for executives in every industry, human resources (HR) organizations are poised to have their day in the sun—proving not just their administrative worth but their strategic value as well.  To make good on that promise, however, HR must modernize. Indeed, if HR is to act as an agent of change—providing the swift reallocation of employees  and the rapid absorption of employee data required for enterprises to shift course on a dime—it must first deal with the disruptive change at its own front door. And increasingly, that means choosing the right technology and human resources management system (HRMS) for managing the entire employee lifecycle. Unfortunately, for most organizations, this task has proved easier said than done. This is because while much has been written about advances in HRMS technology, until recently, most of those advances took the form of disparate on-premises solutions designed to serve very specific purposes. Although this may have resulted in key competencies in certain areas, it also meant that processes for core HR functions like payroll and benefits were being carried out in separate systems from those used for talent management, workforce optimization, training, and so on. With no integration—and no single system of record—processes were disconnected, ease of use was impeded, user experience was diminished, and vital data was left untapped.  Today, however, that scenario has begun to change, and end-to-end cloud-based HCM solutions have moved from wished-for innovations to real-life solutions. Why, then, have HR organizations been so slow in adopting them? The answer—it would seem—is, “It’s complicated.” So complicated, in fact, that 45 percent of the respondents to PwC’s “Annual HR Technology Survey” (for 2013) reported having no formal HR software roadmap, and 40 percent stated that they “did not know” whether their organizations would be increasing their use of cloud or software as a service (SaaS) for HR.  Clearly, HR organizations need help sorting through the morass of HR software options confronting them. But just as clearly, there’s an enormous opportunity awaiting those that do. The trick will come in charting a course that allows HR to leverage existing technology while investing in the cloud-based solutions that will deliver the end-to-end processes, easy-to-understand analytics, and superior adaptability required to simplify—and add value to—every aspect of employee management. The Opportunity therefore is to cut costs, drive Innovation, and increase engagement by moving to cloud-based HCM.  Then you will benefit from one Interface, leverage many access points, and  gain at-a-glance insight across your entire workforce. With many legacy on-premises HR systems not being efficient anymore and cloud-based, integrated systems that span the range of HR functions finally reaching maturity, the time is ripe for moving core HR to the cloud. Indeed, for the first time ever there are more HRMS replacement initiatives than HRMS upgrade initiatives under way, and the majority of them involve moving to the cloud per Cedar Crestone’s 2013-2014 HRMS survey. To learn how you can launch your own cloud HCM initiative and begin using HR to power the enterprise, visit Oracle HRMS in the Cloud and Oracle’s new customer 2 cloud program. Anke Mogannam brings more than 16 years of marketing and human capital management experience in the technology industries to her role at Oracle where she is part of the Human Capital Management applications marketing team. In that role, Anke drives content marketing, messaging, go-to-market activities, integrated marketing campaigns, and field enablement. Prior to joining Oracle, Anke held several roles in communications, marketing, HCM product strategy and product management at PeopleSoft, SAP, Workday and Saba. Follow her on Twitter @amogannam

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  • Veranstaltungshinweis: 2. Oracle Breakfast

    - by nospam(at)example.com (Joerg Moellenkamp)
    Am 26. April findet das zweite Oracle Oracle Breakfast in Hamburg in der Geschäftsstelle (Kühnehöfe 5) statt: Also Futtern mit technischem Content. Auch diesmal gibt es zwei Vorträge. Agenda 9:30Willkommen zum Frühstück 10:00Solaris 11 im Detail - Einbindung in heterogene Netze (CIFS-Dienst etc.)Joerg Moellenkamp 11:30Kaffeepause 12:00ZFSSA praktischEinbindung einer ZFS SA in heterogene Netze, aber wie? Vortrag & Livedemo unter VirtualBoxDirk Nitschke 13:30geplantes Ende Anmelden könnt Ihr euch mit einer formlosen Mail an [email protected]. Das ist ein Forwarder an die Addresse der Kollegin, die das intern bei uns organisiert, deren Mailaddresse ich nicht unbedingt für Spammer verteilen möchte ...

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  • The Other Side of XBRL

    - by john.orourke(at)oracle.com
    With the United States SEC's mandate for XBRL filings entering its third year, and impacting over 7000 additional companies in 2011, there's a lot of buzz in the industry about how companies should address the new reporting requirements.  Should they outsource the XBRL tagging process to a third party publisher, handle the process in-house with a bolt-on XBRL tool, or should they integrate XBRL tagging with the financial close and reporting process?  Oracle is recommending the latter approach, in fact  here's a link to a recent webcast that I did with CFO.com on this topic: http://www.cfo.com/webcasts/index.cfm/l_eventarchive/14548560 But production of XBRL-based filings is only half of the story. The other half is consumption of XBRL by regulators, academics, financial analysts and investors.  As I mentioned in my December article on the XBRL US conference, the feedback from these groups is that they are not really leveraging XBRL for analysis of companies due to a lack of tools and historic XBRL-based data on public companies.   The good news here is that the historic data problem is getting better as large, accelerated filers enter their third year of XBRL filings.  And the situation is getting better on the reporting and analysis tools side of the equation as well - and Oracle is leading the way. In early January, Oracle released the Oracle XBRL Extension for Oracle Database 11g.  This is a "no cost option" on top of the latest Oracle Database 11.2.0.2.0 release. With this added functionality organizations will have the ability to create one or more back-end XBRL repositories based on Oracle Database, which provide XBRL storage and query-ability with a set of XBRL-specific services.  The XBRL Extension to Oracle XML DB integrates easily with Oracle Business Intelligence Suite Enterprise Edition (OBIEE) for analytics and with interactive development environments (IDEs) and design tools for creating and editing XBRL taxonomies. The Oracle XBRL Extension to Oracle Database 11g should be attractive to regulators, stock exchanges, universities and other organizations that need to collect, analyze and disseminate XBRL-based filings.  It should also be attractive to organizations that produce XBRL filings, and need a way to store and compare their own XBRL-based financial filings to those of their peers and competitors. If you would like more information, here's a link to a web page on the Oracle Technology Network with the details about Oracle XBRL Extension for Oracle Database 11g, including data sheet, white paper, presentation, demos and other information: http://www.oracle.com/technetwork/database/features/xmldb/index-087631.html

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  • IsNullOrEmpty generic method for Array to avoid Re-Sharper warning

    - by Michael Freidgeim
    I’ve used the following extension method in many places. public static bool IsNullOrEmpty(this Object[] myArr) { return (myArr == null || myArr.Length == 0); }Recently I’ve noticed that Resharper shows warning covariant array conversion to object[] may cause an exception for the following codeObjectsOfMyClass.IsNullOrEmpty()I’ve resolved the issue by creating generic extension method public static bool IsNullOrEmpty<T>(this T[] myArr) { return (myArr == null || myArr.Length == 0); }Related linkshttp://connect.microsoft.com/VisualStudio/feedback/details/94089/add-isnullorempty-to-array-class    public static bool IsNullOrEmpty(this System.Collections.IEnumerable source)        {            if (source == null)                return true;            else            {                return !source.GetEnumerator().MoveNext();            }        }http://stackoverflow.com/questions/8560106/isnullorempty-equivalent-for-array-c-sharp

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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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  • The Uganda .NET Usergroup meeting for January 2011 - a look back.

    - by Malisa L. Ncube
    We had a very interesting meeting on Friday 28th last week. We had 10 attendees and two speakers. The first topic presented was Cloud Computing, presented by Allan Rwakatungu @arwakatungu who works with MTN Uganda. He gave a very brilliant outline of how Cloud computing and service oriented applications had begun changing the platform for operating business and the costs it saves because of scalability and elasticity. He went on to demonstrate the steps you would take if you are beginning a new Windows Azure project. He explained the history and evolution of the Windows Azure, SQL Azure and cloud services offered by Amazon and google.com. The attendees had many questions to ask (obviously), but they were all answered very well. We once again thank Allan, for taking time to prepare the presentation and demonstrating for us. We recorded a video on the entire presentation and after doing some editing we will publish it. One wish which was echoed by most members was that Microsoft should open the cloud services and development for Africa. Microsoft currently does not even have servers here in Africa and so far, that does not put African developers in the same platform as other developers in other continents. Now is the time considering the improvements in network speeds and joining of the Seacom network and broadband.   I presented on Parallelism and Multithreading using .NET 4.0, I also gave some details on the language changes in C# 5.0 and the async keyword and the TaskEx class. I explained the Task, Scheduling of parallel tasks and demonstrated problems that may arise from using parallelism inappropriately. I also demonstrated the performance improvements that may be achieved by taking advantage of multi-core processors. You may download the presentation on Parallelism and Multi-threading from here. The resolution of the meeting was that we should meet more than once a month and begin other activities which should be more fun. e.g. Geek Dinner, Geek Beer or CodeCamp. Based on that we all agreed we shall have a mid-month meeting starting from February. Cheers folks! del.icio.us Tags: .net,usergroup,cloud computing,parallelism,multi-threading

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  • C#/.NET Little Wonders: Interlocked Read() and Exchange()

    - by James Michael Hare
    Once again, in this series of posts I look at the parts of the .NET Framework that may seem trivial, but can help improve your code by making it easier to write and maintain. The index of all my past little wonders posts can be found here. Last time we discussed the Interlocked class and its Add(), Increment(), and Decrement() methods which are all useful for updating a value atomically by adding (or subtracting).  However, this begs the question of how do we set and read those values atomically as well? Read() – Read a value atomically Let’s begin by examining the following code: 1: public class Incrementor 2: { 3: private long _value = 0; 4:  5: public long Value { get { return _value; } } 6:  7: public void Increment() 8: { 9: Interlocked.Increment(ref _value); 10: } 11: } 12:  It uses an interlocked increment, as we discuss in my previous post (here), so we know that the increment will be thread-safe.  But, to realize what’s potentially wrong we have to know a bit about how atomic reads are in 32 bit and 64 bit .NET environments. When you are dealing with an item smaller or equal to the system word size (such as an int on a 32 bit system or a long on a 64 bit system) then the read is generally atomic, because it can grab all of the bits needed at once.  However, when dealing with something larger than the system word size (reading a long on a 32 bit system for example), it cannot grab the whole value at once, which can lead to some problems since this read isn’t atomic. For example, this means that on a 32 bit system we may read one half of the long before another thread increments the value, and the other half of it after the increment.  To protect us from reading an invalid value in this manner, we can do an Interlocked.Read() to force the read to be atomic (of course, you’d want to make sure any writes or increments are atomic also): 1: public class Incrementor 2: { 3: private long _value = 0; 4:  5: public long Value 6: { 7: get { return Interlocked.Read(ref _value); } 8: } 9:  10: public void Increment() 11: { 12: Interlocked.Increment(ref _value); 13: } 14: } Now we are guaranteed that we will read the 64 bit value atomically on a 32 bit system, thus ensuring our thread safety (assuming all other reads, writes, increments, etc. are likewise protected).  Note that as stated before, and according to the MSDN (here), it isn’t strictly necessary to use Interlocked.Read() for reading 64 bit values on 64 bit systems, but for those still working in 32 bit environments, it comes in handy when dealing with long atomically. Exchange() – Exchanges two values atomically Exchange() lets us store a new value in the given location (the ref parameter) and return the old value as a result. So just as Read() allows us to read atomically, one use of Exchange() is to write values atomically.  For example, if we wanted to add a Reset() method to our Incrementor, we could do something like this: 1: public void Reset() 2: { 3: _value = 0; 4: } But the assignment wouldn’t be atomic on 32 bit systems, since the word size is 32 bits and the variable is a long (64 bits).  Thus our assignment could have only set half the value when a threaded read or increment happens, which would put us in a bad state. So instead, we could write Reset() like this: 1: public void Reset() 2: { 3: Interlocked.Exchange(ref _value, 0); 4: } And we’d be safe again on a 32 bit system. But this isn’t the only reason Exchange() is valuable.  The key comes in realizing that Exchange() doesn’t just set a new value, it returns the old as well in an atomic step.  Hence the name “exchange”: you are swapping the value to set with the stored value. So why would we want to do this?  Well, anytime you want to set a value and take action based on the previous value.  An example of this might be a scheme where you have several tasks, and during every so often, each of the tasks may nominate themselves to do some administrative chore.  Perhaps you don’t want to make this thread dedicated for whatever reason, but want to be robust enough to let any of the threads that isn’t currently occupied nominate itself for the job.  An easy and lightweight way to do this would be to have a long representing whether someone has acquired the “election” or not.  So a 0 would indicate no one has been elected and 1 would indicate someone has been elected. We could then base our nomination strategy as follows: every so often, a thread will attempt an Interlocked.Exchange() on the long and with a value of 1.  The first thread to do so will set it to a 1 and return back the old value of 0.  We can use this to show that they were the first to nominate and be chosen are thus “in charge”.  Anyone who nominates after that will attempt the same Exchange() but will get back a value of 1, which indicates that someone already had set it to a 1 before them, thus they are not elected. Then, the only other step we need take is to remember to release the election flag once the elected thread accomplishes its task, which we’d do by setting the value back to 0.  In this way, the next thread to nominate with Exchange() will get back the 0 letting them know they are the new elected nominee. Such code might look like this: 1: public class Nominator 2: { 3: private long _nomination = 0; 4: public bool Elect() 5: { 6: return Interlocked.Exchange(ref _nomination, 1) == 0; 7: } 8: public bool Release() 9: { 10: return Interlocked.Exchange(ref _nomination, 0) == 1; 11: } 12: } There’s many ways to do this, of course, but you get the idea.  Running 5 threads doing some “sleep” work might look like this: 1: var nominator = new Nominator(); 2: var random = new Random(); 3: Parallel.For(0, 5, i => 4: { 5:  6: for (int j = 0; j < _iterations; ++j) 7: { 8: if (nominator.Elect()) 9: { 10: // elected 11: Console.WriteLine("Elected nominee " + i); 12: Thread.Sleep(random.Next(100, 5000)); 13: nominator.Release(); 14: } 15: else 16: { 17: // not elected 18: Console.WriteLine("Did not elect nominee " + i); 19: } 20: // sleep before check again 21: Thread.Sleep(1000); 22: } 23: }); And would spit out results like: 1: Elected nominee 0 2: Did not elect nominee 2 3: Did not elect nominee 1 4: Did not elect nominee 4 5: Did not elect nominee 3 6: Did not elect nominee 3 7: Did not elect nominee 1 8: Did not elect nominee 2 9: Did not elect nominee 4 10: Elected nominee 3 11: Did not elect nominee 2 12: Did not elect nominee 1 13: Did not elect nominee 4 14: Elected nominee 0 15: Did not elect nominee 2 16: Did not elect nominee 4 17: ... Another nice thing about the Interlocked.Exchange() is it can be used to thread-safely set pretty much anything 64 bits or less in size including references, pointers (in unsafe mode), floats, doubles, etc.  Summary So, now we’ve seen two more things we can do with Interlocked: reading and exchanging a value atomically.  Read() and Exchange() are especially valuable for reading/writing 64 bit values atomically in a 32 bit system.  Exchange() has value even beyond simply atomic writes by using the Exchange() to your advantage, since it reads and set the value atomically, which allows you to do lightweight nomination systems. There’s still a few more goodies in the Interlocked class which we’ll explore next time! Technorati Tags: C#,CSharp,.NET,Little Wonders,Interlocked

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  • SharePoint Saturday LA&ndash;Free Conference

    - by MOSSLover
    There are four really cool national board members for Women in SharePoint, Cathy Dew, Nedra Allmond, Michelle Strah, and and Lori Gowin.  Nedra is running Women in SharePoint West and she just also happens to be helping out with SharePoint Saturday LA.  If you guys had no idea that California also has SharePoint Saturdays then you were wrong.  There is a SharePoint Saturday on April 2nd in the greater Los Angeles Area.  If anyone is interested in the vicinity please visit this site: http://www.sharepointsaturday.org/la/default.aspx. Technorati Tags: SharePoint Saturday,Los Angeles,SharePoint 2010,SharePoint Events

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  • Part 6: Extensions vs. Modifications

    - by volker.eckardt(at)oracle.com
    Customizations = Extensions + Modifications In the EBS terminology, a customization can be an extension or a modification. Extension means that you mainly create your own code from scratch. You may utilize existing views, packages and java classes, but your code is unique. Modifications are quite different, because here you take existing code and change or enhance certain areas to achieve a slightly different behavior. Important is that it doesn't matter if you place your code at the same or at another place – it is a modification. It is also not relevant if you leave the original code enabled or not! Why? Here is the answer: In case the original code piece you have taken as your base will get patched, you need to copy the source again and apply all your changes once more. If you don't do that, you may get different results or write different data compared to the standard – this causes a high risk! Here are some guidelines how to reduce the risk: Invest a bit longer when searching for objects to select data from. Rather choose a view than a table. In case Oracle development changes the underlying tables, the view will be more stable and is therefore a better choice. Choose rather public APIs over internal APIs. Same background as before: although internal structure might change, the public API is more stable. Use personalization and substitution rather than modification. Spend more time to check if the requirement can be covered with such techniques. Build a project code library, avoid that colleagues creating similar functionality multiple times. Otherwise you have to review lots of similar code to determine the need for correction. Use the technique of “flagged files”. Flagged files is a way to mark a standard deployment file. If you run the patch analyse (within Application Manager), the analyse result will list flagged standard files in case they will be patched. If you maintain a cross reference to your own CEMLIs, you can easily determine which CEMLIs have to be reviewed. Implement a code review process. This can be done by utilizing team internal or external persons. If you implement such a team internal process, your team members will come up with suggestions how to improve the code quality by themselves. Review heavy customizations regularly, to identify options to reduce complexity; let's say perform this every 6th month. You may not spend days for such a review, but a high level cross check if the customization can be reduced is suggested. De-install customizations which are no more required. Define a process for this. Add a section into the technical documentation how to uninstall and what are possible implications. Maintain a cross reference between CEMLIs and between CEMLIs, EBS modules and business processes. Keep this list up to date! Share this list! By following these guidelines, you are able to improve product stability. Although we might not be able to avoid modifications completely, we can give a much better advise to developers and to our test team. Summary: Extensions and Modifications have to be handled differently during their lifecycle. Modifications implicate a much higher risk and should therefore be reviewed more frequently. Good cross references allow you to give clear advise for the testing activities.

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  • F# &ndash; It&rsquo;s time to grow up baby.

    - by MarkPearl
    In the last few months since I started learning F# I have begin to notice an increase in the number of people blogging about the language. Sure, it could just be that I am noticing it more because I am actively looking out for questions and blog posts, but even in my day to day reading of Code Project Daily News and Stack Overflow questions there seems to be increased activity around the language. So what sparked this post? Well, today today I logged in and saw that the latest podcast by DNR was on F# and then immediately afterwards I received an email from CodeProject with a great article comparing F# and Scala. Currently, as of this blog posting (21 May 2010) F# is ranked on the tiobe site at position 43, but I am willing to put money on it that in the next few tiobe ratings this ranking will continue to rise till F# will be a top 20.

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  • Happy Birthday Java EE 6+GlassFish 3!

    - by reza_rahman
    It has been almost exactly three years since Java EE 6 and GlassFish 3 were announced. It's worth pausing a moment to take stock of what has happened since. Both Java EE 6 and GlassFish 3 have been game changers. EE 6 has brought Java EE back in the limelight. To see evidence of that look at presentations like these from independents like Bert Ertman and Paul Bakker: JavaOne 2011: Migrating Spring Applications to Java EE 6 from ertmanb Likewise, the GlassFish community has proven to be a powerful disruptive force in the Java application server landscape. It's impact is evident from this percent growth rate chart from indeed.com of major Java application servers: Please join us in wishing both GlassFish and Java EE a very happy birthday and many more to come with Java EE 7, GlassFish 4 and Oracle's capabale stewardship...

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  • APEX Patchset 4.2.1 erschienen

    - by Carsten Czarski
    Seit Freitag, dem 14.12. steht das APEX Patchset 4.2.1 zur Verfügung. Neben zahlreichen Bugfixes sind auch einige, kleinere Änderungen enthalten: Die JQuery Mobile Bibliothek wurde auf Version 1.2.0 aktualisiert Die AnyChart-Engine wurde auf Version 6.0.11 gehoben. Dadurch stehen "Circular Gauge" Charts auch als HTML5 Diagramme bereit Diagramme in Anwendungen für mobile Endgeräte können sich nun dynamisch der Bildschirmgröße anpassen Details zum Patchset finden sich, wie immer in den Release Notes. Wie bislang unterscheidet sich der Installationsvorgang je nach verwendeter APEX-Version. Wenn noch kein APEX oder eine ältere Version als 4.2 installiert ist, kann die Vollinstallation für APEX 4.2.1 direkt aus dem OTN heruntergeladen und normal installiert werden. Wenn APEX 4.2.0 installiert ist, muss Patch Nr. 14732511 aus MyOracle Support heruntergeladen und eingespielt werden.

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  • Personal Financial Management – The need for resuscitation

    - by Salil Ravindran
    Until a year or so ago, PFM (Personal Financial Management) was the blue eyed boy of every channel banking head. In an age when bank account portability is still fiction, PFM was expected to incentivise customers to switch banks. It still is, in some emerging economies, but if the state of PFM in matured markets is anything to go by, it is in a state of coma and badly requires resuscitation. Studies conducted around the year show an alarming decline and stagnation in PFM usage in mature markets. A Sept 2012 report by Aite Group – Strategies for PFM Success shows that 72% of users hadn’t used PFM and worse, 58% of them were not kicked about using it. Of the rest who had used it, only half did on a bank site. While there are multiple reasons for this lack of adoption, some are glaringly obvious. While pretty graphs and pie charts are important to provide a visual representation of my income and expense, it is simply not enough to encourage me to return. Static representation of data without any insightful analysis does not help me. Budgeting and Cash Flow is important but when I have an operative account, a couple of savings accounts, a mortgage loan and a couple of credit cards help me with what my affordability is in specific contexts rather than telling me I just busted my budget. Help me with relative importance of each budget category so that I know it is fine to go over budget on books for my daughter as against going over budget on eating out. Budget over runs and spend analysis are post facto and I am informed of my sins only when I return to online banking. That too, only if I decide to come to the PFM area. Fundamentally, PFM should be a part of my banking engagement rather than an analysis tool. It should be contextual so that I can make insight based decisions. So what can be done to resuscitate PFM? Amalgamation with banking activities – In most cases, PFM tools are integrated into online banking pages and they are like chapter 37 of a long story. PFM needs to be a way of banking rather than a tool. Available balances should shift to Spendable Balances. Budget and goal related insights should be integrated with transaction sessions to drive pre-event financial decisions. Personal Financial Guidance - Banks need to think ground level and see if their PFM offering is really helping customers achieve self actualisation. Banks need to recognise that most customers out there are non-proficient about making the best value of their money. Customers return when they know that they are being guided rather than being just informed on their finance. Integrating contextual financial offers and financial planning into PFM is one way ahead. Yet another way is to help customers tag unwanted spending thereby encouraging sound savings habits. Mobile PFM – Most banks have left all those numbers on online banking. With access mostly having moved to devices and the success of apps, moving PFM on to devices will give it a much needed shot in the arm. This is not only about presenting the same wine in a new bottle but also about leveraging the power of the device in pushing real time notifications to make pre-purchase decisions. The pursuit should be to analyse spend, budgets and financial goals real time and push them pre-event on to the device. So next time, I should know that I have over run my eating out budget before walking into that burger joint and not after. Increase participation and collaboration – Peer group experiences and comments are valued above those offered by the bank. Integrating social media into PFM engagement will let customers share and solicit their financial management experiences with their peer group. Peer comparisons help benchmark one’s savings and spending habits with those of the peer group and increases stickiness. While mature markets have gone through this learning in some way over the last one year, banks in maturing digital banking economies increasingly seem to be falling into this trap. Best practices lie in profiling and segmenting customers, being where they are and contextually guiding them to identify and achieve their financial goals. Banks could look at the likes of Simple and Movenbank to draw inpiration from.

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  • ADF EMG at Oracle Open World 2012: Forms to FMW

    - by ultan o'broin
    A super menu of sessions from the Oracle Application Development Framework Enterprise Methodology Group (that's ADF EMG to the rest of you) folks is now lined up for Oracle Open World 2012 (OOW12). These sessions fall under the category of "The Year After the Year of the ADF Developer" and cover everything for developers of enterprise apps with the Oracle toolkits, be they coming from an Oracle Forms background or on Oracle Fusion Middleware (FMW). Sessions also explain the architecture, building and deployment of Oracle Application Development Framework (ADF) apps. Anyone interested in developing enterprise applications with ADF should be beating a path to these now. Guaranteed rock star developer (and wannabe) stuff! A great return on investment for your attendance at OOW12. See you there!

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  • Webcor Builders Coordinates Construction Schedules and Mitigates Potential Delays More Efficiently with Integrated Project Management

    - by Sylvie MacKenzie, PMP
    Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* 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:10.0pt; font-family:"Times New Roman","serif";} With more than 40 years of commercial construction experience, Webcor Builders is a leading builder of distinguished, high-profile projects, including high-rise condominiums and hotels, laboratories, healthcare centers, and public works projects. Webcor is also known for its award-winning concrete, interior construction, historic restoration, and seismic renovation work. The company has completed more than 50 million square feet of projects to date. Considering the variety and complexity of the construction projects Webcor undertakes, an integrated project management solution is critical to ensuring optimal efficiency and completing client projects on time and on budget. The company previously used a number of scheduling systems for its various building projects. These packages provided different levels of schedule detail and required schedulers, engineers, and other employees to learn multiple systems. From an IT cost and complexity perspective, the company had to manage multiple scheduling systems and pay for multiple sets of licenses. The company looked to standardize on an enterprise project management system, and selected Oracle’s Primavera P6 Enterprise Project Portfolio Management. Webcor uses the solution’s advanced capabilities to schedule complex projects, analyze delays, model and propose multiple scenarios to demonstrate and mitigate delays and cost overruns, and process that information efficiently to deliver the scheduling precision that public and private projects require. In fact, the solution was instrumental in helping the company’s expansion into public sector projects during the recent economic downturn, and with Primavera P6 in place, it can deliver the precise schedule reporting required for large public projects. With Primavera P6 in place, the company could deliver the precise scheduling and milestone reporting capabilities required for large public projects. The solution is in managing the high-profile University of California – Berkeley Memorial Stadium project. Webcor was hired as construction manager and general contractor for the stadium renovation project, which is a fast-paced project located near the seismically active Hayward Fault Zone. Due to the University of California’s football schedule, meeting the Universities deadline for the coming season placed Webcor in a situation where risk awareness and early warnings of issues would be paramount. Webcor and the extended project team needed a solution that could instantly analyze alternate scenarios to mitigate potential delays; Primavera would deliver those answers.The team would also need to enable multiple stakeholders to use an internet-based platform to access the schedule from various locations, and model complicated sequencing requirements where swift decisions would be made to keep the project on track. The schedule is an integral part of Webcor’s construction management process for the stadium project. Rather than providing the client with the industry-standard monthly update, Webcor updates the critical path method (CPM) schedule on a weekly basis. The project team also reviews the schedule and updates weekly to confirm that progress and forecasted performance are accurate. Hired by the University for their ability to deliver in high risk environments The Webcor team was hit recently with a design supplement that could have added up to 70 days to the project. Using Oracle Primavera P6 the team sprung into action analyzing multiple “what if” scenarios to review mitigation means and methods.  Determined to make sure the Bears could take the field in the coming season the project team nearly eliminated the impact with their creative analysis in working the schedule. The total time from the issuance of the final design supplement to an agreed mitigation response was less than one week; leveraging the Oracle Primavera solution Webcor was able to deliver superior customer value With the ability to efficiently manage projects and schedules, Webcor can ensure it completes its projects on time and on budget, as well as inform clients about what changes to plans will mean in terms of delays and additional costs. Read the complete customer case study at :  http://www.oracle.com/us/corporate/customers/customersearch/webcor-builders-1-primavera-ss-1639886.html

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  • Brand New Oracle WebLogic 12c Online Launch Event, December 1st, 18:00 GMT

    - by swalker
    The brand new WebLogic 12c will be released on December 1st 2011. Please join Hasan Rizvi on December 1, as he unveils the next generation of the industry’s #1 application server and cornerstone of Oracle’s cloud application foundation—Oracle WebLogic Server 12c. Hear, with your fellow IT managers, architects, and developers, how the new release of Oracle WebLogic Server is: Designed to help you seamlessly move into the public or private cloud with an open, standards-based platform Built to drive higher value for your current infrastructure and significantly reduce development time and cost Optimized to run your solutions for Java Platform, Enterprise Edition (Java EE); Oracle Fusion Middleware; and Oracle Fusion Applications Enhanced with transformational platforms and technologies such as Java EE 6, Oracle’s Active GridLink for RAC, Oracle Traffic Director, and Oracle Virtual Assembly Builder Don’t miss this online launch event on December 1st, 18:00 GMT. Register Now For regular information become a member of the WebLogic Partner Community please register at http://www.oracle.com/partners/goto/wls-emea

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  • RemoveHandler Issues with Custom Events

    - by Jeff Certain
    This is a case of things being more complicated that I thought they should be. Since it took a while to figure this one out, I thought it was worth explaining and putting all of the pieces to the answer in one spot. Let me set the stage. Architecturally, I have the notion of generic producers and consumers. These put items onto, and remove items from, a queue. This provides a generic, thread-safe mechanism to load balance the creation and processing of work items in our application. Part of the IProducer(Of T) interface is: 1: Public Interface IProducer(Of T) 2: Event ItemProduced(ByVal sender As IProducer(Of T), ByVal item As T) 3: Event ProductionComplete(ByVal sender As IProducer(Of T)) 4: End Interface Nothing sinister there, is there? In order to simplify our developers’ lives, I wrapped the queue with some functionality to manage the produces and consumers. Since the developer can specify the number of producers and consumers that are spun up, the queue code manages adding event handlers as the producers and consumers are instantiated. Now, we’ve been having some memory leaks and, in order to eliminate the possibility that this was caused by weak references to event handles, I wanted to remove them. This is where it got dicey. My first attempt looked like this: 1: For Each producer As P In Producers 2: RemoveHandler producer.ItemProduced, AddressOf ItemProducedHandler 3: RemoveHandler producer.ProductionComplete, AddressOf ProductionCompleteHandler 4: producer.Dispose() 5: Next What you can’t see in my posted code are the warnings this caused. The 'AddressOf' expression has no effect in this context because the method argument to 'AddressOf' requires a relaxed conversion to the delegate type of the event. Assign the 'AddressOf' expression to a variable, and use the variable to add or remove the method as the handler.  Now, what on earth does that mean? Well, a quick Bing search uncovered a whole bunch of talk about delegates. The first solution I found just changed all parameters in the event handler to Object. Sorry, but no. I used generics precisely because I wanted type safety, not because I wanted to use Object. More searching. Eventually, I found this forum post, where Jeff Shan revealed a missing piece of the puzzle. The other revelation came from Lian_ZA in this post. However, these two only hinted at the solution. Trying some of what they suggested led to finally getting an invalid cast exception that revealed the existence of ItemProducedEventHandler. Hold on a minute! I didn’t create that delegate. There’s nothing even close to that name in my code… except the ItemProduced event in the interface. Could it be? Naaaaah. Hmmm…. Well, as it turns out, there is a delegate created by the compiler for each event. By explicitly creating a delegate that refers to the method in question, implicitly cast to the generated delegate type, I was able to remove the handlers: 1: For Each producer As P In Producers 2: Dim _itemProducedHandler As IProducer(Of T).ItemProducedEventHandler = AddressOf ItemProducedHandler 3: RemoveHandler producer.ItemProduced, _itemProducedHandler 4:  5: Dim _productionCompleteHandler As IProducer(Of T).ProductionCompleteEventHandler = AddressOf ProductionCompleteHandler 6: RemoveHandler producer.ProductionComplete, _productionCompleteHandler 7: producer.Dispose() 8: Next That’s “all” it took to finally be able to remove the event handlers and maintain type-safe code. Hopefully, this will save you the same challenges I had in trying to figure out how to fix this issue!

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  • JAX-RS 2.0, JTA 1.1, JMS 2.0 Replay: Java EE 7 Launch Webinar Technical Breakouts on YouTube

    - by John Clingan
    As stated previously (here) (here), the On-Demand Replay of Java EE 7 Launch Webinar is already available. You can watch the entire Strategy and Technical Keynote there, and all other Technical Breakout sessions as well. We are releasing the next set of Technical Breakout sessions on GlassFishVideos YouTube channel as well. In this series, we are releasing JAX-RS 2.0, JTA 1.1, and JMS 2.0. Here's the JAX-RS 2.0 session: Enjoy watching them over the next few days before we release the next set of videos! And don't forget to download Java EE 7 SDK and try numerous bundled samples. "here), we are releasing the next set of Technical Breakout sessions on GlassFishVideos YouTube channel as well. In this series, the next three videos are released. Here's the JAX-RS 2.0 session: Enjoy watching them over the next few days before we release the next set of videos! And don't forget to download Java EE 7 SDK and try numerous bundled samples.

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  • Are your merchandise systems limiting growth? Oracle Retail's Merchandise Operations Management could be the answer

    - by user801960
    In this video, Lara Livgard, Director of Oracle Retail Strategy, introduces Oracle Retail Merchandise Operations Management (MOM), a set of integrated, modular solutions that support buying, pricing, inventory management and inventory valuation across a retailer’s channels, countries, and business models. MOM is the backbone of successful retail operations, providing timely and accurate visibility across the entire enterprise and enabling efficient supply-chain execution driven by plans and forecasts. It's modular architecture facilitates tailored and high-value implementations, giving retailers the information they need in order to offer a quality customer experience through a truly integrated multi-channel approach. Further information is available on the Oracle Retail website regarding Merchandise Operations Management.

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  • BizTalk 2009 - The Community ODBC Adapter: Schema Generation

    - by Stuart Brierley
    Having previously detailed the installation of the Community ODBC Adapter for BizTalk 2009, the next thing I will be looking at is the generation of schemas using this ODBC adapter. Within your BizTalk 2009 project, right click the project and select Add Generated Items.  In the resultant window choose Add Adapter Metadata and click Add to open the Add Adapter Wizard. Check that the BizTalk Server and Database names are correct, select the ODBC adapter and click next. You must now set the connection string. To start with choose set, then new DSN (data source name). You now need to define the Data Source you will be connecting to.  On the User DSN tab select Add add then driver you want to use. In this case I am going to use the MySQL ODBC Driver.  A User DSN will only be visible on the current machine with you as a user. * Although I initially set up a User DSN and this was fine for creating schemas with, I later realised that you actually need a system DSN as the BizTalk host service needs this to be able connect to the database on a receive or send port. You will then be asked to Set up the MySQL ODBC Data Source.  In my case this is a local database making use of named pipes, so I had to make sure that I ticked the "Force use of named pipes" check box and removed the "# The Pipe the MySQL Server will use socket=mysql" line from the mysql.ini; with this is place the connection would fail as there is no apparent way to specify the pipe name in the ODBC driver configuration. This will then update the User DSN tab with the new Data Source.  Make sure that you select it and press OK. Select it again in the Choose Data Source window and press OK.  On the ODBC transport window select next. You will now be presented with the Schema Information window, where you must supply the namespace, type and root element names for your schema. Next choose the type of statement that you will be using to create your schema - in this case I am using a stored procedure. *I later discovered that this option is fine for MySQL stored procedures without input parameters, but failed for MySQL stored procedures with input parameters.  (I will be posting on the way to handle input parameters soon) Next you will need to specify the name of the stored procedure.  In this case I have a simple stored procedure to return all the data held by my TestTable in MySQL. Select * from TestTable; The table itself has three columns: Name, Sex and Married. Selecting finish should now hopefully create your schemas based on the input and output from your stored procedure. In my case I have:   An empty schema for the request; after all I have no parameters for the stored procedure.  A response schema comprised of a Table Record with Name, Sex and Married children. Next I will be looking at the use of the ODBC adpater with: Receive ports Send ports

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  • Mobile or the Science of Programming Languages

    - by user12652314
    Just two things to share today. First is some news in the mobile computing space and a pretty cool new relationship developing with DubLabs and AT&T to enable a student-centric mobile experience for our Campus Solution customers. And second, is an interesting article shared by a friend on Research in Programming Languages related to STEM education, a key story element to my project with Americas Cup and iED, but also to our national interest

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  • "Oracle Coherence 3.5" Book - My Humble Review

    - by [email protected]
      After reviewing the book in more detail I say again that it is a great guide for sure. Lots of important concepts that sometimes can be somewhat confusing are deeply reviewed, including all types of caching schemes and backing maps, and the cache topologies with their corresponding performances and very useful "When to use it?" sections. Some functionalities that are very desirable or used a lot are reviewed with examples and best practices of implementation, including: Data affinity Querying Pagination Indexes Aggregations Event processing, listening and triggering Data persistence Security Regarding the networking and architecture topics, Coherence*Extend is exhaustively reviewed, including C++ and .NET clients, with very good tips and examples, even including source codes. Personally, I am also glad to see that the address providers (<address-provider> tag), new feature in Coherence 3.5 which is a way to programmatically provide well-known addresses in order to connect to the cluster, is mentioned on the book, because it provides new functionalities to satisfy some special configuration requirements for example: Provide a way to switch extend nodes in cases of failure Implement custom load balancing algorithms and/or dynamic discovery of TCP/IP connection acceptors Dynamically assign TCP address and port settings when binding to a server socket Another very interesting and useful section is the "Coherent Bank Sample Application", which is a great tutorial, useful to understand how Coherence interacts with third party products establishing a clear integration with them, including the use of non-Oracle products like MS Visual Studio.  

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  • Of transactions and Mongo

    - by Nuri Halperin
    Originally posted on: http://geekswithblogs.net/nuri/archive/2014/05/20/of-transactions-and-mongo-again.aspxWhat's the first thing you hear about NoSQL databases? That they lose your data? That there's no transactions? No joins? No hope for "real" applications? Well, you *should* be wondering whether a certain of database is the right one for your job. But if you do so, you should be wondering that about "traditional" databases as well! In the spirit of exploration let's take a look at a common challenge: You are a bank. You have customers with accounts. Customer A wants to pay B. You want to allow that only if A can cover the amount being transferred. Let's looks at the problem without any context of any database engine in mind. What would you do? How would you ensure that the amount transfer is done "properly"? Would you prevent a "transaction" from taking place unless A can cover the amount? There are several options: Prevent any change to A's account while the transfer is taking place. That boils down to locking. Apply the change, and allow A's balance to go below zero. Charge person A some interest on the negative balance. Not friendly, but certainly a choice. Don't do either. Options 1 and 2 are difficult to attain in the NoSQL world. Mongo won't save you headaches here either. Option 3 looks a bit harsh. But here's where this can go: ledger. See, and account doesn't need to be represented by a single row in a table of all accounts with only the current balance on it. More often than not, accounting systems use ledgers. And entries in ledgers - as it turns out – don't actually get updated. Once a ledger entry is written, it is not removed or altered. A transaction is represented by an entry in the ledger stating and amount withdrawn from A's account and an entry in the ledger stating an addition of said amount to B's account. For sake of space-saving, that entry in the ledger can happen using one entry. Think {Timestamp, FromAccountId, ToAccountId, Amount}. The implication of the original question – "how do you enforce non-negative balance rule" then boils down to: Insert entry in ledger Run validation of recent entries Insert reverse entry to roll back transaction if validation failed. What is validation? Sum up the transactions that A's account has (all deposits and debits), and ensure the balance is positive. For sake of efficiency, one can roll up transactions and "close the book" on transactions with a pseudo entry stating balance as of midnight or something. This lets you avoid doing math on the fly on too many transactions. You simply run from the latest "approved balance" marker to date. But that's an optimization, and premature optimizations are the root of (some? most?) evil.. Back to some nagging questions though: "But mongo is only eventually consistent!" Well, yes, kind of. It's not actually true that Mongo has not transactions. It would be more descriptive to say that Mongo's transaction scope is a single document in a single collection. A write to a Mongo document happens completely or not at all. So although it is true that you can't update more than one documents "at the same time" under a "transaction" umbrella as an atomic update, it is NOT true that there' is no isolation. So a competition between two concurrent updates is completely coherent and the writes will be serialized. They will not scribble on the same document at the same time. In our case - in choosing a ledger approach - we're not even trying to "update" a document, we're simply adding a document to a collection. So there goes the "no transaction" issue. Now let's turn our attention to consistency. What you should know about mongo is that at any given moment, only on member of a replica set is writable. This means that the writable instance in a set of replicated instances always has "the truth". There could be a replication lag such that a reader going to one of the replicas still sees "old" state of a collection or document. But in our ledger case, things fall nicely into place: Run your validation against the writable instance. It is guaranteed to have a ledger either with (after) or without (before) the ledger entry got written. No funky states. Again, the ledger writing *adds* a document, so there's no inconsistent document state to be had either way. Next, we might worry about data loss. Here, mongo offers several write-concerns. Write-concern in Mongo is a mode that marshals how uptight you want the db engine to be about actually persisting a document write to disk before it reports to the application that it is "done". The most volatile, is to say you don't care. In that case, mongo would just accept your write command and say back "thanks" with no guarantee of persistence. If the server loses power at the wrong moment, it may have said "ok" but actually no written the data to disk. That's kind of bad. Don't do that with data you care about. It may be good for votes on a pole regarding how cute a furry animal is, but not so good for business. There are several other write-concerns varying from flushing the write to the disk of the writable instance, flushing to disk on several members of the replica set, a majority of the replica set or all of the members of a replica set. The former choice is the quickest, as no network coordination is required besides the main writable instance. The others impose extra network and time cost. Depending on your tolerance for latency and read-lag, you will face a choice of what works for you. It's really important to understand that no data loss occurs once a document is flushed to an instance. The record is on disk at that point. From that point on, backup strategies and disaster recovery are your worry, not loss of power to the writable machine. This scenario is not different from a relational database at that point. Where does this leave us? Oh, yes. Eventual consistency. By now, we ensured that the "source of truth" instance has the correct data, persisted and coherent. But because of lag, the app may have gone to the writable instance, performed the update and then gone to a replica and looked at the ledger there before the transaction replicated. Here are 2 options to deal with this. Similar to write concerns, mongo support read preferences. An app may choose to read only from the writable instance. This is not an awesome choice to make for every ready, because it just burdens the one instance, and doesn't make use of the other read-only servers. But this choice can be made on a query by query basis. So for the app that our person A is using, we can have person A issue the transfer command to B, and then if that same app is going to immediately as "are we there yet?" we'll query that same writable instance. But B and anyone else in the world can just chill and read from the read-only instance. They have no basis to expect that the ledger has just been written to. So as far as they know, the transaction hasn't happened until they see it appear later. We can further relax the demand by creating application UI that reacts to a write command with "thank you, we will post it shortly" instead of "thank you, we just did everything and here's the new balance". This is a very powerful thing. UI design for highly scalable systems can't insist that the all databases be locked just to paint an "all done" on screen. People understand. They were trained by many online businesses already that your placing of an order does not mean that your product is already outside your door waiting (yes, I know, large retailers are working on it... but were' not there yet). The second thing we can do, is add some artificial delay to a transaction's visibility on the ledger. The way that works is simply adding some logic such that the query against the ledger never nets a transaction for customers newer than say 15 minutes and who's validation flag is not set. This buys us time 2 ways: Replication can catch up to all instances by then, and validation rules can run and determine if this transaction should be "negated" with a compensating transaction. In case we do need to "roll back" the transaction, the backend system can place the timestamp of the compensating transaction at the exact same time or 1ms after the original one. Effectively, once A or B visits their ledger, both transactions would be visible and the overall balance "as of now" would reflect no change.  The 2 transactions (attempted/ reverted) would be visible , since we do actually account for the attempt. Hold on a second. There's a hole in the story: what if several transfers from A to some accounts are registered, and 2 independent validators attempt to compute the balance concurrently? Is there a chance that both would conclude non-sufficient-funds even though rolling back transaction 100 would free up enough for transaction 117 (some random later transaction)? Yes. there is that chance. But the integrity of the business rule is not compromised, since the prime rule is don't dispense money you don't have. To minimize or eliminate this scenario, we can also assign a single validation process per origin account. This may seem non-scalable, but it can easily be done as a "sharded" distribution. Say we have 11 validation threads (or processing nodes etc.). We divide the account number space such that each validator is exclusively responsible for a certain range of account numbers. Sounds cunningly similar to Mongo's sharding strategy, doesn't it? Each validator then works in isolation. More capacity needed? Chop the account space into more chunks. So where  are we now with the nagging questions? "No joins": Huh? What are those for? "No transactions": You mean no cross-collection and no cross-document transactions? Granted - but don't always need them either. "No hope for real applications": well... There are more issues and edge cases to slog through, I'm sure. But hopefully this gives you some ideas of how to solve common problems without distributed locking and relational databases. But then again, you can choose relational databases if they suit your problem.

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