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  • Bridging the Gap in Cloud, Big Data, and Real-time

    - by Dain C. Hansen
    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:10.0pt; font-family:"Calibri","sans-serif"; mso-bidi-font-family:"Times New Roman";} With all the buzz of around big data and cloud computing, it is easy to overlook one of your most precious commodities—your data. Today’s businesses cannot stand still when it comes to data. Market success now depends on speed, volume, complexity, and keeping pace with the latest data integration breakthroughs. Are you up to speed with big data, cloud integration, real-time analytics? Join us in this three part blog series where we’ll look at each component in more detail. Meet us online on October 24th where we’ll take your questions about what issues you are facing in this brave new world of integration. Let’s start first with Cloud. What happens with your data when you decide to implement a private cloud architecture? Or public cloud? Data integration solutions play a vital role migrating data simply, efficiently, and reliably to the cloud; they are a necessary ingredient of any platform as a service strategy because they support cloud deployments with data-layer application integration between on-premise and cloud environments of all kinds. For private cloud architectures, consolidation of your databases and data stores is an important step to take to be able to receive the full benefits of cloud computing. Private cloud integration requires bidirectional replication between heterogeneous systems to allow you to perform data consolidation without interrupting your business operations. In addition, integrating data requires bulk load and transformation into and out of your private cloud is a crucial step for those companies moving to private cloud. In addition, the need for managing data services as part of SOA/BPM solutions that enable agile application delivery and help build shared data services for organizations. But what about public Cloud? If you have moved your data to a public cloud application, you may also need to connect your on-premise enterprise systems and the cloud environment by moving data in bulk or as real-time transactions across geographies. For public and private cloud architectures both, Oracle offers a complete and extensible set of integration options that span not only data integration but also service and process integration, security, and management. For those companies investing in Oracle Cloud, you can move your data through Oracle SOA Suite using REST APIs to Oracle Messaging Cloud Service —a new service that lets applications deployed in Oracle Cloud securely and reliably communicate over Java Messaging Service . As an example of loading and transforming data into other public clouds, Oracle Data Integrator supports a knowledge module for Salesforce.com—now available on AppExchange. Other third-party knowledge modules are being developed by customers and partners every day. To learn more about how to leverage Oracle’s Data Integration products for Cloud, join us live: Data Integration Breakthroughs Webcast on October 24th 10 AM PST.

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  • Overview of Microsoft SQL Server 2008 Upgrade Advisor

    - by Akshay Deep Lamba
    Problem Like most organizations, we are planning to upgrade our database server from SQL Server 2005 to SQL Server 2008. I would like to know is there an easy way to know in advance what kind of issues one may encounter when upgrading to a newer version of SQL Server? One way of doing this is to use the Microsoft SQL Server 2008 Upgrade Advisor to plan for upgrades from SQL Server 2000 or SQL Server 2005. In this tip we will take a look at how one can use the SQL Server 2008 Upgrade Advisor to identify potential issues before the upgrade. Solution SQL Server 2008 Upgrade Advisor is a free tool designed by Microsoft to identify potential issues before upgrading your environment to a newer version of SQL Server. Below are prerequisites which need to be installed before installing the Microsoft SQL Server 2008 Upgrade Advisor. Prerequisites for Microsoft SQL Server 2008 Upgrade Advisor .Net Framework 2.0 or a higher version Windows Installer 4.5 or a higher version Windows Server 2003 SP 1 or a higher version, Windows Server 2008, Windows XP SP2 or a higher version, Windows Vista Download SQL Server 2008 Upgrade Advisor You can download SQL Server 2008 Upgrade Advisor from the following link. Once you have successfully installed Upgrade Advisor follow the below steps to see how you can use this tool to identify potential issues before upgrading your environment. 1. Click Start -> Programs -> Microsoft SQL Server 2008 -> SQL Server 2008 Upgrade Advisor. 2. Click Launch Upgrade Advisor Analysis Wizard as highlighted below to open the wizard. 2. On the wizard welcome screen click Next to continue. 3. In SQL Server Components screen, enter the Server Name and click the Detect button to identify components which need to be analyzed and then click Next to continue with the wizard. 4. In Connection Parameters screen choose Instance Name, Authentication and then click Next to continue with the wizard. 5. In SQL Server Parameters wizard screen select the Databases which you want to analysis, trace files if any and SQL batch files if any.  Then click Next to continue with the wizard. 6. In Reporting Services Parameters screen you can specify the Reporting Server Instance name and then click next to continue with the wizard. 7. In Analysis Services Parameters screen you can specify an Analysis Server Instance name and then click Next to continue with the wizard. 8. In Confirm Upgrade Advisor Settings screen you will be able to see a quick summary of the options which you have selected so far. Click Run to start the analysis. 9. In Upgrade Advisor Progress screen you will be able to see the progress of the analysis. Basically, the upgrade advisor runs predefined rules which will help to identify potential issues that can affect your environment once you upgrade your server from a lower version of SQL Server to SQL Server 2008. 10. In the below snippet you can see that Upgrade Advisor has completed the analysis of SQL Server, Analysis Services and Reporting Services. To see the output click the Launch Report button at the bottom of the wizard screen. 11. In View Report screen you can see a summary of issues which can affect you once you upgrade. To learn more about each issue you can expand the issue and read the detailed description as shown in the below snippet.

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  • Speaker at the German Visual FoxPro Developer Conference 2003

    The following is an excerpt from the UniversalThread conference coverage of the German Visual FoxPro Developer Conference 2003 written by Hans-Otto Lochmann and Armin Neudert. Track: Visual FoxPro and Linux This track consists of 4 sessions presented on one day in one sequence. Originally the Linux portion of this track was to be presented by Whil Hentzen, the well-known publisher, book author and confer-ence speaker. Unfortunately some illness prevented him from joining this DevCon. Rainer got the bad news only on early Friday morning. It was definitely to late to find a replacement among the already invited speaker on such a short notice. So Rainer decided to take over these "three sessions in a row" by himself with "a little help from his friends". He hired a coach for him for the weekend and prepared slides and sessions by himself - the originally planed slides and session material were still in USA. Rainer survived barely an endless disaster of C0000005's due to various wrong configuration settings... At the presentation Jochen Kirstätter helped massively with technical details regarding Linux whereas Rainer did the slides and the presentation. Gerold Lübben then presented the MySQL part - as originally planned. This track concentrated on the how to run Visual FoxPro applications on Linux machines with the help of a Windows emulator like Wine. As more and more people use Linux machines in production (and not just for running servers), more and more invitations to bid for a development job includes the requirement to run the application in a Linux environment. If you would like to participate in such submissions, then you should get familiar with the open source operating system Linux and the open source Data Base system MySQL. [...] These sessions provided a broad, complete overview of where Linux fits into the current computing landscape from the perspective of a VFP developer, where VFP can be used with Linux, and a conceptual plan for how to approach the incorporation of Linux into your day-to-day work. In order for you to be able to work with a Linux back end, you're going to need to know something about how Linux works. The best way involves a two-step process: First, plunk down a Linux workstation on your desk next to your Windows machine and develop some experience with the new OS.Second, once you have a basic level of comfort with Linux, gained through your experience on a workstation, leverage that knowledge and learn to connect to a Linux server from your Windows machine. This track showed both of these processes: What you can expect when you set up your Linux work-station, how to set it up, how to connect to your Windows network, how to fit VFP into the mix, and even how you could use it to replace your Windows workstation in some cases. Also this track demonstrated how to connect to an existing Linux server, running MySQL or an another back end, and how to get your VFP apps talking to that back end data. This track also showed both of the positions you can take. Rainer disliked it wholeheartedly (the bad guy position in these talks) and Jochen loved it (the good guy and "typical Linux techie"-position we all love). These opposite position lasted for three sessions and both sides where shown with their Pros and Cons in live and lively discussions of the speakers (club banging was forbidden). Gerold Luebben showed how Visual Foxpro and MySQL can work together. MySQL is as one the most well known open SOURCE databases for nearly all platforms available. Particularly in eBusiness MySQL is well positioned and well known for its performance and its stability. Still we like Visual FoxPro more - for sure . [...]

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  • FairWarning Privacy Monitoring Solutions Rely on MySQL to Secure Patient Data

    - by Rebecca Hansen
    FairWarning® solutions have audited well over 120 billion events, each of which was processed and stored in a MySQL database. FairWarning is the world's leading supplier of privacy monitoring solutions for electronic health records, relied on by over 1,200 Hospitals and 5,000 Clinics to keep their patients' data safe. In January 2014, FairWarning was awarded the highest commendation in healthcare IT as the first ever Category Leader for Patient Privacy Monitoring in the "2013 Best in KLAS: Software & Services" report[1]. FairWarning has used MySQL as their solutions’ database from their start in 2005 to worldwide expansion and market leadership. FairWarning recently migrated their solutions from MyISAM to InnoDB and updated from MySQL 5.5 to 5.6. Following are some of benefits they’ve had as a result of those changes and reasons for their continued reliance on MySQL (from FairWarning MySQL Case Study). Scalability to Handle Terabytes of Data FairWarning's customers have a lot of data: On average, FairWarning customers receive over 700,000 events to be processed daily. Over 25% of their customers receive over 30 million events per day, which equates to over 1 billion events and nearly one terabyte (TB) of new data each month. Databases range in size from a few hundred GBs to 10+ TBs for enterprise deployments (data are rolled off after 13 months). Low or Zero Admin = Few DBAs "MySQL has not required a lot of administration. After it's been tuned, configured, and optimized for size on initial setup, we have very low administrative costs. I can scale and add more customers without adding DBAs. This has had a big, positive impact on our business.” - Chris Arnold, FairWarning Vice President of Product Management and Engineering. Performance Schema  As the size of FairWarning's customers has increased, so have their tables and data volumes. MySQL 5.6’ new maintenance and management features have helped FairWarning keep up. In particular, MySQL 5.6 performance schema’s low-level metrics have provided critical insight into how the system is performing and why. Support for Mutli-CPU Threads MySQL 5.6' support for multiple concurrent CPU threads, and FairWarning's custom data loader allow multiple files to load into a single table simultaneously vs. one at a time. As a result, their data load time has been reduced by 500%. MySQL Enterprise Hot Backup Because hospitals and clinics never stop, FairWarning solutions can’t either. FairWarning changed from using mysqldump to MySQL Enterprise Hot Backup, which has reduced downtime, restore time, and storage requirements. For many of their larger customers, restore time has decreased by 80%. MySQL Enterprise Edition and Product Roadmap Provide Complete Solution "MySQL's product roadmap fully addresses our needs. We like the fact that MySQL Enterprise Edition has everything included; there's no need to purchase separate modules."  - Chris Arnold Learn More>> FairWarning MySQL Case Study Why MySQL 5.6 is an Even Better Embedded Database for Your Products presentation Updating Your Products to MySQL 5.6, Best Practices for OEMs on-demand webinar (audio and / or slides + Q&A transcript) MyISAM to InnoDB – Why and How on-demand webinar (same stuff) Top 10 Reasons to Use MySQL as an Embedded Database white paper [1] 2013 Best in KLAS: Software & Services report, January, 2014. © 2014 KLAS Enterprises, LLC. All rights reserved.

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  • Database Mirroring on SQL Server Express Edition

    - by Most Valuable Yak (Rob Volk)
    Like most SQL Server users I'm rather frustrated by Microsoft's insistence on making the really cool features only available in Enterprise Edition.  And it really doesn't help that they changed the licensing for SQL 2012 to be core-based, so now it's like 4 times as expensive!  It almost makes you want to go with Oracle.  That, and a desire to have Larry Ellison do things to your orifices. And since they've introduced Availability Groups, and marked database mirroring as deprecated, you'd think they'd make make mirroring available in all editions.  Alas…they don't…officially anyway.  Thanks to my constant poking around in places I'm not "supposed" to, I've discovered the low-level code that implements database mirroring, and found that it's available in all editions! It turns out that the query processor in all SQL Server editions prepends a simple check before every edition-specific DDL statement: IF CAST(SERVERPROPERTY('Edition') as nvarchar(max)) NOT LIKE '%e%e%e% Edition%' print 'Lame' else print 'Cool' If that statement returns true, it fails. (the print statements are just placeholders)  Go ahead and test it on Standard, Workgroup, and Express editions compared to an Enterprise or Developer edition instance (which support everything). Once again thanks to Argenis Fernandez (b | t) and his awesome sessions on using Sysinternals, I was able to watch the exact process SQL Server performs when setting up a mirror.  Surprisingly, it's not actually implemented in SQL Server!  Some of it is, but that's something of a smokescreen, the real meat of it is simple filesystem primitives. The NTFS filesystem supports links, both hard links and symbolic, so that you can create two entries for the same file in different directories and/or different names.  You can create them using the MKLINK command in a command prompt: mklink /D D:\SkyDrive\Data D:\Data mklink /D D:\SkyDrive\Log D:\Log This creates a symbolic link from my data and log folders to my Skydrive folder.  Any file saved in either location will instantly appear in the other.  And since my Skydrive will be automatically synchronized with the cloud, any changes I make will be copied instantly (depending on my internet bandwidth of course). So what does this have to do with database mirroring?  Well, it seems that the mirroring endpoint that you have to create between mirror and principal servers is really nothing more than a Skydrive link.  Although it doesn't actually use Skydrive, it performs the same function.  So in effect, the following statement: ALTER DATABASE Mir SET PARTNER='TCP://MyOtherServer.domain.com:5022' Is turned into: mklink /D "D:\Data" "\\MyOtherServer.domain.com\5022$" The 5022$ "port" is actually a hidden system directory on the principal and mirror servers. I haven't quite figured out how the log files are included in this, or why you have to SET PARTNER on both principal and mirror servers, except maybe that mklink has to do something special when linking across servers.  I couldn't get the above statement to work correctly, but found that doing mklink to a local Skydrive folder gave me similar functionality. To wrap this up, all you have to do is the following: Install Skydrive on both SQL Servers (principal and mirror) and set the local Skydrive folder (D:\SkyDrive in these examples) On the principal server, run mklink /D on the data and log folders to point to SkyDrive: mklink /D D:\SkyDrive\Data D:\Data On the mirror server, run the complementary linking: mklink /D D:\Data D:\SkyDrive\Data Create your database and make sure the files map to the principal data and log folders (D:\Data and D:\Log) Viola! Your databases are kept in sync on multiple servers! One wrinkle you will encounter is that the mirror server will show the data and log files, but you won't be able to attach them to the mirror SQL instance while they are attached to the principal. I think this is a bug in the Skydrive, but as it turns out that's fine: you can't access a mirror while it's hosted on the principal either.  So you don't quite get automatic failover, but you can attach the files to the mirror if the principal goes offline.  It's also not exactly synchronous, but it's better than nothing, and easier than either replication or log shipping with a lot less latency. I will end this with the obvious "not supported by Microsoft" and "Don't do this in production without an updated resume" spiel that you should by now assume with every one of my blog posts, especially considering the date.

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  • Creating a branch for every Sprint

    - by Martin Hinshelwood
    There are a lot of developers using version control these days, but a feature of version control called branching is very poorly understood and remains unused by most developers in favour of Labels. Most developers think that branching is hard and complicated. Its not! What is hard and complicated is a bad branching strategy. Just like a bad software architecture a bad branch architecture, or one that is not adhered to can prove fatal to a project. We I was at Aggreko we had a fairly successful Feature branching strategy (although the developers hated it) that meant that we could have multiple feature teams working at the same time without impacting each other. Now, this had to be carefully orchestrated as it was a Business Intelligence team and many of the BI artefacts do not lend themselves to merging. Today at SSW I am working on a Scrum team delivering a product that will be used by many hundreds of developers. SSW SQL Deploy takes much of the pain out of upgrading production databases when you are not using the Database projects in Visual Studio. With Scrum each Scrum Team works for a fixed period of time on a single sprint. You can have one or more Scrum Teams involved in delivering a product, but all the work must be merged and tested, ready to be shown to the Product Owner at the the Sprint Review meeting at the end of the current Sprint. So, what does this mean for a branching strategy? We have been using a “Main” (sometimes called “Trunk”) line and doing a branch for each sprint. It’s like Feature Branching, but with only ONE feature in operation at any one time, so no conflicts Figure: DEV folder containing the Development branches.   I know that some folks advocate applying a Label at the start of each Sprint and then rolling back if you need to, but I have always preferred the security of a branch. Like: being able to create a release from Main that has Sprint3 code even while Sprint4 is being worked on. being sure I can always create a stable build on request. Being able to guarantee a version (labels are not auditable) Be able to abandon the sprint without having to delete the code (rare I know, but would be a mess if it happened) Being able to see the flow of change sets through to a safe release It helps you find invalid dependencies when merging to Main as there may be some file that is in everyone’s Sprint branch, but never got checked in. (We had this at the merge of Sprint2) If you are always operating in this way as a standard it makes it easier to then add more scrum teams in the future. Muscle memory of this way of working. Don’t Like: Additional DB space for the branches Baseless merging between sprint branches when changes are directly ported Note: I do not think we will ever attempt this! Maybe a bit tougher to see the history between sprint branches since the changes go up through Main and down to another sprint branch Note: What you would have to do is see which Sprint the changes were made in and then check the history he same file in that Sprint. A little bit of added complexity that you would have to do anyway with multiple teams. Over time, you can end up with a lot of old unused sprint branches. Perhaps destroy with /keephistory can help in this case. Note: We ALWAYS delete the Sprint branch after it has been merged into Main. That is the theory anyway, and as you can see from the images Sprint2 has already been deleted. Why take the chance of having a problem rolling back or wanting to keep some of the code, when you can just abandon a branch and start a new one? It just seems easier and less painful to use a branch to me! What do you think?   Technorati Tags: TFS,TFS2010,Software Development,ALM,Branching

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  • ATG Live Webcast June 28: Scrambling Sensitive Data in EBS 12 Cloned Environments

    - by BillSawyer
    Securing the Oracle E-Business Suite includes protecting the underlying E-Business data in production and non-production databases.  While steps can be taken to provide a secure configuration to limit EBS access, a better approach to protecting non-production data is simply to scramble (mask) the data in the non-production copy.   The Oracle E-Business Suite Template for Data Masking Pack can be used in situations where confidential or regulated data needs to be shared with other non-production users who need access to some of the original data, but not necessarily every table.  Examples of non-production users include internal application developers or external business partners such as offshore testing companies, suppliers or customers. The Oracle E-Business Suite Template for Data Masking Pack is applied to a non-production environment with the Enterprise Manager Grid Control Data Masking Pack.  When applied, the Oracle E-Business Suite Template for Data Masking Pack will create an irreversibly scrambled version of your production database for development and testing. This ATG Live Webcast is your chance to come learn about the Oracle E-Business Suite Release 12.1.3 Template for Data Masking Pack from the experts. Oracle E-Business Suite Release 12.1.3 Template for Data Masking The agenda for the Oracle E-Business Suite Template for Data Masking Pack webcast includes the following topics: What does data masking do in E-Business Suite environments? De-identify the data Mask sensitive data Maintain data validity How can EBS customers use data masking? References Join Eric Bing, Senior Director and Elke Phelps, Senior Principal Product Manager, as they discusses the Oracle E-Business Suite Template for Data Masking Pack.Date:                  Thursday, June 28, 2012Time:                 8:00AM Pacific Standard TimePresenters:     Eric Bing, Senior Director                           Elke Phelps, Senior Principal Product ManagerWebcast Registration Link (Preregistration is optional but encouraged) To hear the audio feed:    Domestic Participant Dial-In Number:           877-697-8128    International Participant Dial-In Number:      706-634-9568    Additional International Dial-In Numbers Link:    Dial-In Passcode:                                              100865To see the presentation:    The Direct Access Web Conference details are:    Website URL: https://ouweb.webex.com    Meeting Number:  599097152If you miss the webcast, or you have missed any webcast, don't worry -- we'll post links to the recording as soon as it's available from Oracle University.  You can monitor this blog for pointers to the replay. And, you can find our archive of our past webcasts and training here.If you have any questions or comments, feel free to email Bill Sawyer (Senior Manager, Applications Technology Curriculum) at BilldotSawyer-AT-Oracle-DOT-com.

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  • Multidimensional Thinking–24 Hours of Pass: Celebrating Women in Technology

    - by smisner
    It’s Day 1 of #24HOP and it’s been great to participate in this event with so many women from all over the world in one long training-fest. The SQL community has been abuzz on Twitter with running commentary which is fun to watch while listening to the current speaker. If you missed the fun today because you’re busy with all that work you’ve got to do – don’t despair. All sessions are recorded and will be available soon. Keep an eye on the 24 Hours of Pass page for details. And the fun’s not over today. Rather than run 24 hours consecutively, #24HOP is now broken down into 12-hours over two days, so check out the schedule to see if there’s a session that interests you and fits your schedule. I’m pleased to announce that my business colleague Erika Bakse ( Blog | Twitter) will be presenting on Day 2 – her debut presentation for a PASS event. (And I’m also pleased to say she’s my daughter!) Multidimensional Thinking: The Presentation My contribution to this lineup of terrific speakers was Multidimensional Thinking. Here’s the abstract: “Whether you’re developing Analysis Services cubes or creating PowerPivot workbooks, you need to get into a multidimensional frame of mind to produce a model that best enables users to answer their business questions on their own. Many database professionals struggle initially with multidimensional models because the data modeling process is much different than the one they use to produce traditional, third normal form databases. In this session, I’ll introduce you to the terminology of multidimensional modeling and step through the process of translating business requirements into a viable model.” If you watched the presentation and want a copy of the slides, you can download a copy here. And you’re welcome to download the slides even if you didn’t watch the presentation, but they’ll make more sense if you did! Kimball All the Way There’s only so much I can cover in the time allotted, but I hope that I succeeded in my attempt to build a foundation that prepares you for starting out in business intelligence. One of my favorite resources that will get into much more detail about all kinds of scenarios (well beyond the basics!) is The Data Warehouse Toolkit (Second Edition) by Ralph Kimball. Anything from Kimball or the Kimball Group is worth reading. Kimball material might take reading and re-reading a few times before it makes sense. From my own experience, I found that I actually had to just build my first data warehouse using dimensional modeling on faith that I was going the right direction because it just didn’t click with me initially. I’ve had years of practice since then and I can say it does get easier with practice. The most important thing, in my opinion, is that you simply must prototype a lot and solicit user feedback, because ultimately the model needs to make sense to them. They will definitely make sure you get it right! Schema Generation One question came up after the presentation about whether we use SQL Server Management Studio or Business Intelligence Development Studio (BIDS) to build the tables for the dimensional model. My answer? It really doesn’t matter how you create the tables. Use whatever method that you’re comfortable with. But just so happens that it IS possible to set up your design in BIDS as part of an Analysis Services project and to have BIDS generate the relational schema for you. I did a Webcast last year called Building a Data Mart with Integration Services that demonstrated how to do this. Yes, the subject was Integration Services, but as part of that presentation, I showed how to leverage Analysis Services to build the tables, and then I showed how to use Integration Services to load those tables. I blogged about this presentation in September 2010 and included downloads of the project that I used. In the blog post, I explained that I missed a step in the demonstration. Oops. Just as an FYI, there were two more Webcasts to finish the story begun with the data – Accelerating Answers with Analysis Services and Delivering Information with Reporting Services. If you want to just cut to the chase and learn how to use Analysis Services to build the tables, you can see the Using the Schema Generation Wizard topic in Books Online.

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  • A Case for Oracle Fusion Middleware by Lucas Jellema

    - by JuergenKress
    An in-depth look at the interaction of people, processes, and technologies in the transition to a service-oriented architecture. Author's Note This article presents a profile of a fictitious organization, NOPERU. The story of NOPERU as told in this article is actually a collage of the events at some dozen organizations that I have been involved with over the past few years. None of these organizations sport all the characteristics of NOPERU - but all of them have gone through or are going through a similar transition as described here and all aspects of this article were taken from real life at one or usually many of these organizations. Background NOPERU (National Organization for Permits for Emissions and Resource Usage) is a public organization that continues to transform in terms of its business, organization and technology. Changing business requirements; new interaction channels; and increasing demands for more flexibility, faster throughput and lower costs drive these transformations, while technological evolution and new architecture patterns enable the change. NOPERU chose Oracle Fusion Middleware as the technology platform to implement the new architecture and required applications. This article takes a close look at NOPERU's journey from its origins in the early 1990s as a largely paper-based entity with regional databases and client-server Oracle Forms applications. Its upcoming business objectives are introduced: what is required of the organization and what the higher goals behind these requirements are. The architecture roadmap is described at a high level as well as drilled down to a service oriented design. Based on the architecture roadmap and the business requirements and NOPERU went through a technology selection to determine the technology stack with which the future would be realized in terms of IT. The article discusses that selection and details the projects subsequently planned (and executed to date). The new architecture and technology as well as the introduction of an Agile development method have had substantial consequences for the IT organization, the processes and individual staff members. The approach NOPERU has adopted with regard to the people and the organization is portrayed. Finally, the article discusses many conclusions that NOPERU has drawn that may benefit itself and other organizations. Introducing NOPERU NOPERU is a national organization charged with issuing permits for excessive emissions (i.e., carbon dioxide) and disproportionate usage of such resources as energy or water. Anyone-whether a commercial enterprise, government agency or private person--who emits or consumes more than what is considered "fair usage" requires such a permit. When someone builds an outdoor heated swimming pool, for example, or open-air terrace heating, such a permit needs to be obtained. When a company installs new, energy-intensive equipment, such as water boilers or deep freezers, it too needs to get a NOPERU permit. Government-sponsored projects at every level that involve consumption of large quantities of fresh water or production of high volumes of emissions must turn to NOPERU for a permit. Without the required license, any interested party can get a court to immediately put a stop to the disputed activity. Read the full article here. SOA & BPM Partner Community For regular information on Oracle SOA Suite become a member in the SOA & BPM Partner Community for registration please visit www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Facebook Wiki Mix Forum Technorati Tags: Lucas Jellema,SOA Community,Oracle SOA,Oracle BPM,Community,OPN,Jürgen Kress

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  • SPARC T4-2 Produces World Record Oracle Essbase Aggregate Storage Benchmark Result

    - by Brian
    Significance of Results Oracle's SPARC T4-2 server configured with a Sun Storage F5100 Flash Array and running Oracle Solaris 10 with Oracle Database 11g has achieved exceptional performance for the Oracle Essbase Aggregate Storage Option benchmark. The benchmark has upwards of 1 billion records, 15 dimensions and millions of members. Oracle Essbase is a multi-dimensional online analytical processing (OLAP) server and is well-suited to work well with SPARC T4 servers. The SPARC T4-2 server (2 cpus) running Oracle Essbase 11.1.2.2.100 outperformed the previous published results on Oracle's SPARC Enterprise M5000 server (4 cpus) with Oracle Essbase 11.1.1.3 on Oracle Solaris 10 by 80%, 32% and 2x performance improvement on Data Loading, Default Aggregation and Usage Based Aggregation, respectively. The SPARC T4-2 server with Sun Storage F5100 Flash Array and Oracle Essbase running on Oracle Solaris 10 achieves sub-second query response times for 20,000 users in a 15 dimension database. The SPARC T4-2 server configured with Oracle Essbase was able to aggregate and store values in the database for a 15 dimension cube in 398 minutes with 16 threads and in 484 minutes with 8 threads. The Sun Storage F5100 Flash Array provides more than a 20% improvement out-of-the-box compared to a mid-size fiber channel disk array for default aggregation and user-based aggregation. The Sun Storage F5100 Flash Array with Oracle Essbase provides the best combination for large Oracle Essbase databases leveraging Oracle Solaris ZFS and taking advantage of high bandwidth for faster load and aggregation. Oracle Fusion Middleware provides a family of complete, integrated, hot pluggable and best-of-breed products known for enabling enterprise customers to create and run agile and intelligent business applications. Oracle Essbase's performance demonstrates why so many customers rely on Oracle Fusion Middleware as their foundation for innovation. Performance Landscape System Data Size(millions of items) Database Load(minutes) Default Aggregation(minutes) Usage Based Aggregation(minutes) SPARC T4-2, 2 x SPARC T4 2.85 GHz 1000 149 398* 55 Sun M5000, 4 x SPARC64 VII 2.53 GHz 1000 269 526 115 Sun M5000, 4 x SPARC64 VII 2.4 GHz 400 120 448 18 * – 398 mins with CALCPARALLEL set to 16; 484 mins with CALCPARALLEL threads set to 8 Configuration Summary Hardware Configuration: 1 x SPARC T4-2 2 x 2.85 GHz SPARC T4 processors 128 GB memory 2 x 300 GB 10000 RPM SAS internal disks Storage Configuration: 1 x Sun Storage F5100 Flash Array 40 x 24 GB flash modules SAS HBA with 2 SAS channels Data Storage Scheme Striped - RAID 0 Oracle Solaris ZFS Software Configuration: Oracle Solaris 10 8/11 Installer V 11.1.2.2.100 Oracle Essbase Client v 11.1.2.2.100 Oracle Essbase v 11.1.2.2.100 Oracle Essbase Administration services 64-bit Oracle Database 11g Release 2 (11.2.0.3) HP's Mercury Interactive QuickTest Professional 9.5.0 Benchmark Description The objective of the Oracle Essbase Aggregate Storage Option benchmark is to showcase the ability of Oracle Essbase to scale in terms of user population and data volume for large enterprise deployments. Typical administrative and end-user operations for OLAP applications were simulated to produce benchmark results. The benchmark test results include: Database Load: Time elapsed to build a database including outline and data load. Default Aggregation: Time elapsed to build aggregation. User Based Aggregation: Time elapsed of the aggregate views proposed as a result of tracked retrieval queries. Summary of the data used for this benchmark: 40 flat files, each of size 1.2 GB, 49.4 GB in total 10 million rows per file, 1 billion rows total 28 columns of data per row Database outline has 15 dimensions (five of them are attribute dimensions) Customer dimension has 13.3 million members 3 rule files Key Points and Best Practices The Sun Storage F5100 Flash Array has been used to accelerate the application performance. Setting data load threads (DLTHREADSPREPARE) to 64 and Load Buffer to 6 improved dataloading by about 9%. Factors influencing aggregation materialization performance are "Aggregate Storage Cache" and "Number of Threads" (CALCPARALLEL) for parallel view materialization. The optimal values for this workload on the SPARC T4-2 server were: Aggregate Storage Cache: 32 GB CALCPARALLEL: 16   See Also Oracle Essbase Aggregate Storage Option Benchmark on Oracle's SPARC T4-2 Server oracle.com Oracle Essbase oracle.com OTN SPARC T4-2 Server oracle.com OTN Oracle Solaris oracle.com OTN Oracle Database 11g Release 2 Enterprise Edition oracle.com OTN Disclosure Statement Copyright 2012, Oracle and/or its affiliates. All rights reserved. Oracle and Java are registered trademarks of Oracle and/or its affiliates. Other names may be trademarks of their respective owners. Results as of 28 August 2012.

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  • Introducing MySQL for Excel

    - by Javier Treviño
    As part of the new product initiatives of the MySQL on Windows group we released a tool that makes the task of getting data in and out of a MySQL Database very friendly and intuitive, and we paired it with one of the preferred applications for data analysis and manipulation in Windows platforms, MS Excel. Welcome to MySQL for Excel, an add-in that is installed and accessed from within the MS Excel’s Data tab offering a wizard-like interface arranged in an elegant yet simple way to help users browse MySQL Schemas, Tables, Views and Procedures and perform data operations against them using MS Excel as the vehicle to drive the data in and out MySQL Databases. One of the coolest features we had in mind designing MySQL for Excel is simplicity. MS Excel is simple and easy to work with, thus liked by many Windows users because they don’t have to be software gurus to use it.  We applied the same principle by targeting MySQL for Excel to any kind of user, so if you are already familiarized with Excel’s interface you will find yourself working with MySQL data in no time. MySQL for Excel is shipped within the MySQL Installer as one of the tools in the suite; if prerequisites are already installed (.NET Framework 4.0, Visual Studio Tools for Office 4.0 and of course MS Office), installing the add-in involves a very few clicks and no further setup to use it. Being an Excel Add-In there is no executable file involved after the installation, running MS Excel and opening the add-in from its Data tab is all that is required. MySQL for Excel automatically integrates with MySQL Workbench (if installed) to share the same connections to MySQL Server installations, that way connections are defined just once in either product saving time.  Opening the Add-In brings the Welcome Panel at the right side of the Excel main window from which connections to MySQL Servers are shown grouped by Local VS Remote connections; then users can open any of those connections by double-clicking it and entering the password of the used account.  Additionally a user can create a connection by clicking on the New Connection action label or edit connections through MySQL Workbench (if installed) by clicking on the Manage Connections action label. Once a connection is opened, the Schema Selection panel is shown, at the top of it the selected connection (connection name, hostname/IP and username). Just below, a list of schemas is displayed where User Schemas are grouped first followed by System Schemas; users can double-click any selected schema to go to the next panel or select a schema and clicking the Next > button. Users can alternatively click on the < Back button to go back to the Welcome Panel to close the current connection and open a new one; also by clicking the Create New Schema action label they can create an empty new schema. Once a schema is opened the DB Object Selection panel is shown, this is actually the place where the fun stuff happens; from here users are able to perform actions against MySQL Tables, Views and Procedures. ">The actions available here are about importing data from a MySQL Table, View or Procedure to Excel, exporting Excel data to a new MySQL Table, appending Excel data to an existing MySQL Table or editing a MySQL Table’s data by using an Excel Worksheet as a user interface to update data in any row/column, insert new rows or delete existing rows in a very easy and friendly way. More blog posts will follow describing all of these actions, so stay tuned! Remember that your feedback is very important for us, so drop us a message: · MySQL on Windows (this) Blog - https://blogs.oracle.com/MySqlOnWindows/ · Forum - http://forums.mysql.com/list.php?172 · Facebook - http://www.facebook.com/mysql Cheers!

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  • What Counts For a DBA: Ego

    - by Louis Davidson
    Leaving aside, for a second, Freud’s psychoanalytical definitions, the term “ego” generally refers to a person’s sense of self, and their self-esteem. In casual usage, however, it usually appears in the adjectival form, “egotistical” (most often followed by “jerk”). You don’t need to be a jerk to be a DBA; humility is important. However, ego is important too. A good DBA needs a certain degree of self-esteem…a belief and pride in what he or she can do better than anyone else can. The ideal DBA needs to be humble enough to admit when they are wrong but egotistical enough to know when they are right, and to stand up for that knowledge and make their voice heard. In most organizations, the DBA team is seriously outnumbered by headstrong developers and clock driven managers, and “great” DBAs will often be outnumbered by…well…the not so great. In order to be heard in this environment, a DBA will not only need to be very skilled, but will also need a healthy dose of ego. As Freud might have put it, the unconscious desire of the DBA (the id) is for iron-fist control over their databases, and code that runs in them. However, the ego moderates this desire, seeking to “satisfy the id in realistic ways that, in the long term, bring benefit rather than grief“. In other words, the ego understands the need to exert a measure of control and self-belief, but also to tolerate and play nicely with developers and other DBAs. The trick, naturally, is learning how to be heard when it is important, but also to make everyone around you welcome that input, even when you have to be bold to make the “I know what I am talking about, and you…well…not so much” decisions. Consider a baseball team, bottom of the ninth inning of the championship game, man on first and down one run. Almost anyone on that team will have the ability to hit a home run, but only one or two will have the iron belief that they can pull it off in this critical, end-game situation. The player you need in this situation is the one who has passionately gone the extra mile preparing for just this moment, is bursting at the seams with self-confidence, and can look the coach in the eye and state, boldly, “Put me in, I am your best bet“. Likewise, on those occasions when high customer demand coincides with copious system errors, and panic is bubbling just beneath the surface, you don’t need the minimally qualified support person, armed with the “reboot and hope” technique (though that sometimes works!). You need the DBA who steps up and says, “Put me in” and has the skill and tenacity to back up those words and to fix the pinpoint and fix the problem, whatever it takes, while keeping customers and managers happy. Of course, the egotistical DBA will happily spend hours telling you how great they are at their job, and how brilliantly they put out a previous fire, and this is no guarantee that they can deliver. However, if an otherwise-humble DBA looks you in the eye and says, “I can do it”, then hear them out. Sometimes, this burst of ego will be exactly what’s required.

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  • Guessing Excel Data Types

    - by AjarnMark
    Note to Self HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Jet\4.0\Engines\Excel: TypeGuessRows = 0 means scan everything. Note to Others About 10 years ago I stumbled across this bit of information just when I needed it and it saved my project.  Then for some reason, a few years later when it would have been nice, but not critical, for some reason I could not find it again anywhere.  Well, now I have stumbled across it again, and to preserve my future self from nightmares and sudden baldness due to pulling my hair out, I have decided to blog it in the hopes that I can find it again this way. Here’s the story…  When you query data from an Excel spreadsheet, such as with old-fashioned DTS packages in SQL 2000 (my first reference) or simply with an OLEDB Data Adapter from ASP.NET (recent task) and if you are using the Microsoft Jet 4.0 driver (newer ones may deal with this differently) then you can get funny results where the query reports back that a cell value is null even when you know it contains data. What happens is that Excel doesn’t really have data types.  While you can format information in cells to appear like certain data types (e.g. Date, Time, Decimal, Text, etc.) that is not really defining the cell as being of a certain type like we think of when working with databases.  But, presumably, to make things more convenient for the user (programmer) when you issue a query against Excel, the query processor tries to guess what type of data is contained in each column and returns it in an appropriate manner.  This is all well and good IF your data is consistent in every row and matches what the processor guessed.  And, for efficiency’s sake, when the query processor is trying to figure out each column’s data type, it does so by analyzing only the first 8 rows of data (default setting). Now here’s the problem, suppose that your spreadsheet contains information about clothing, and one of the columns is Size.  Now suppose that in the first 8 rows, all of your sizes look like 32, 34, 18, 10, and so on, using numbers, but then, somewhere after the 8th row, you have some rows with sizes like S, M, L, XL.  What happens is that by examining only the first 8 rows, the query processor inferred that the column contained numerical data, and then when it hits the non-numerical data in later rows, it comes back blank.  Major bummer, and a real pain to track down if you don’t know that Excel is doing this, because you study the spreadsheet and say, “the data is RIGHT THERE!  WHY doesn’t the query see it?!?!”  And the hair-pulling begins. So, what’s a developer to do?  One option is to go to the registry setting noted above and change the DWORD value of TypeGuessRows from the default of 8 to 0 (zero).  Setting this value to zero will force Jet to scan every row in the spreadsheet before making its determination as to what type of data the column contains.  And that means that in the example above, it would have treated the column as a string rather than as numeric, and presto! your query now returns all of the values that you know are in there. Of course, there is a caveat… if you are querying large spreadsheets, making Jet scan every row can be quite a performance hit.  You could enter a different number (more than 8) that you believe is a better sampling of rows to make the guess, but you still have the possibility that every row scanned looks alike, but that later rows are different, and that you might get blanks when there really is data there.  That’s the type of gamble, I really don’t like to take with my data. Anyone with a better approach, or with experience with more recent drivers that have a better way of handling data types, please chime in!

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  • Using Live Data in Database Development Work

    - by Phil Factor
    Guest Editorial for Simple-Talk Newsletter... in which Phil Factor reacts with some exasperation when coming across a report that a majority of companies were still using financial and personal data for both developing and testing database applications. If you routinely test your development work using real production data that contains personal or financial information, you are probably being irresponsible, and at worst, risking a heavy financial penalty for your company. Surprisingly, over 80% of financial companies still do this. Plenty of data breaches and fraud have happened from the use of real data for testing, and a data breach is a nightmare for any organisation that suffers one. The cost of each data breach averages out at around $7.2 million in the US in notification, escalation, credit monitoring, fines, litigation, legal costs, and lost business due to customer churn, £1.9 million in the UK. 70% of data breaches are done from within the organisation. Real data can be exploited in a number of ways for malicious or criminal purposes. It isn't just the obvious use of items such as name and address, date of birth, social security number, and credit card and bank account numbers: Data can be exploited in many subtle ways, so there are excellent reasons to ensure that a high priority is given to the detection and prevention of any data breaches. You'll never successfully guess all the ways that real data can be exploited maliciously, or the ease with which it can be accessed. It would be silly to argue that developers never need access to a copy of the database containing live data. Developers sometimes need to track a bug that can only be replicated on the data from the live database. However, it has to be done in a very restrictive harness. The law makes no distinction between development and production databases when a data breach occurs, so the data has to be held with all appropriate security measures in place. In Europe, the use of personal data for testing requires the explicit consent of the people whose data is being held. There are federal standards such as GLBA, PCI DSS and HIPAA, and most US States have privacy legislation. The task of ensuring compliance and tight security in such circumstances is an expensive and time-consuming overhead. The developer is likely to suffer investigation if a data breach occurs, even if the company manages to stay in business. Ironically, the use of copies of live data isn't usually the most effective way to develop or test your data. Data is usually time-specific and isn't usually current by the time it is used for testing, Existing data doesn't help much for new functionality, and every time the data is refreshed from production, any test data is likely to be overwritten. Also, it is not always going to test all the 'edge' conditions that are likely to flush out bugs. You still have the task of simulating the dynamics of actual usage of the database, and here you have no alternative to creating 'spoofed' data. Because of the complexities of relational data, It used to be that there was no realistic alternative to developing and testing with live data. However, this is no longer the case. Real data can be obfuscated, or it can be created entirely from scratch. The latter process used to be impractical, now that there are plenty of third-party tools to choose from. The process of obfuscation isn't risk free. The process must access the live data, and the success of the obfuscation process has to be carefully monitored. Database data security isn't an exciting topic to you or I, but to a hacker it can be an all-consuming obsession, especially if there is financial or political gain involved. This is not the sort of adversary one would wish for and it is far better to accept, and work with, security restrictions that exist for using live data in database development work, especially when the tools exist to create large realistic database test data that can be better for several aspects of testing.

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  • Access Denied

    - by Tony Davis
    When Microsoft executives wake up in the night screaming, I suspect they are having a nightmare about their own version of Frankenstein's monster. Created with the best of intentions, without thinking too hard of the long-term strategy, and having long outlived its usefulness, the monster still lives on, occasionally wreaking vengeance on the innocent. Its name is Access; a living synthesis of disparate body parts that is resistant to all attempts at a mercy-killing. In 1986, Microsoft had no database products, and needed one for their new OS/2 operating system, the successor to MSDOS. In 1986, they bought exclusive rights to Sybase DataServer, and were also intent on developing a desktop database to capture Ashton-Tate's dominance of that market, with dbase. This project, first called 'Omega' and later 'Cirrus', eventually spawned two products: Visual Basic in 1991 and Access in late 1992. Whereas Visual Basic battled with PowerBuilder for dominance in the client-server market, Access easily won the desktop database battle, with Dbase III and DataEase falling away. Access did an excellent job of abstracting and simplifying the task of building small database applications in a short amount of time, for a small number of departmental users, and often for a transient requirement. There is an excellent front end and forms generator. We not only see it in Access but parts of it also reappear in SSMS. It's good. A business user can pull together useful reports, without relying on extensive technical support. A skilled Access programmer can deliver a fairly sophisticated application, whilst the traditional client-server programmer is still sharpening his pencil. Even for the SQL Server programmer, the forms generator of Access is useful for sketching out application designs. So far, so good, but here's where the problems start; Access ties together two different products and the backend of Access is the bugbear. The limitations of Jet/ACE are well-known and documented. They range from MDB files that are prone to corruption, especially as they grow in size, pathetic security, and "copy and paste" Backups. The biggest problem though, was an infamous lack of scalability. Because Microsoft never realized how long the product would last, they put little energy into improving the beast. Microsoft 'ate their own dog food' by using Access for Microsoft Exchange and Outlook. They choked on it. For years, scalability and performance problems with Exchange Server have been laid at the door of the Jet Blue engine on which it relies. Substantial development work in Exchange 2010 was required, just in order to improve the engine and storage schema so that it more efficiently handled the reading and writing of mails. The alternative of using SQL Server just never panned out. The Jet engine was designed to limit concurrent users to a small number (10-20). When Access applications outgrew this, bitter experience proved that there really is no easy upgrade path from Access to SQL Server, beyond rewriting the whole lot from scratch. The various initiatives to do this never quite bridged the cultural gulf between Access and a true relational database So, what are the obvious alternatives for small, strategic database applications? I know many users who, for simple 'list maintenance' requirements are very happy using Excel databases. Surely, now that PowerPivot has led the way, it is time for Microsoft to offer a new RAD package for database application development; namely an Excel-based front end for SQL Server Express. In that way, we'll have a powerful and familiar front end, to a scalable database, and a clear upgrade path when an app takes off and needs to go enterprise. Cheers, Tony.

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  • Tuning Red Gate: #2 of Many

    - by Grant Fritchey
    In the last installment, I used the SQL Monitor tool to get a snapshot view of the current state of the servers at Red Gate that are giving us trouble. That snapshot suggested some areas where I should focus some time, primarily in which queries were being called most frequently or were running the longest. But, you don't want to just run off & start tuning queries. Remember, the foundation for query tuning is the server itself. So, I want to be sure I'm not looking at some major hardware or configuration issues that I need to address first. Rather than look at the current status of the server, I'm going to look at historical data. Clicking on the Analysis tab of SQL Monitor I get a whole list of counters that I can look at. More importantly, I can look at them over a period of time. Even more importantly, I can compare past periods with current periods to see if we're looking at a progressive issue or not. There are counters here that will give me an indication of load, and there are counters here that will tell me specifics about that load. First, I want to just look at the load to understand where the pain points might be. Trying to drill down before you have detailed information is just bad planning. First thing I'm going to check is the CPU, just to see what's up there. I have two servers I'm interested in, so I'll show you both: Looking at the last 30 days for both servers, well, let's just say that the first server is about what I would expect. It has an average baseline behavior with occasional, regular, peaks. This looks like a system with a fairly steady & predictable load that probably has a nightly batch process that spikes the processor. In short, normal stuff. The points there where the CPU drops radically. that might be worth investigating further because something changed the processing on this system a lot. But the first server. It's all over the place. There's no steady CPU behavior at all. It's spike high for long periods of time. It's up, it's down. I'm really going to have to spend time looking at CPU issues on this server to try to figure out what's up. It might be other processes being shared on the server, it might be something else. Either way, I'm going to have to spend time evaluating this CPU, especially those peeks about a week ago. Looking at the Pages/sec, again, just a measure of load, I see that there are some peaks on the rg-sql02 server, but over all, it looks like a fairly standard load. Plus, the peaks are only up to 550 pages/sec. Remember, this isn't a performance measure, but just a load measurement, but from this, I don't think we're looking at major memory issues, but I may want to correlate these counters with the CPU counters. Again, the other server looks like there's stuff going on. The load is not at all consistent. In fact there was a point earlier in the year that looks pretty severe. Plus the spikes here are twice the size of the other system. We've got a lot more load going on here and I will probably need to drill down on memory usage on this server. Taking a look at the disk transfers/sec the load on both systems seems to roughly correspond to the other load indicators. Notice that drop right in the middle of the graph for rg-sql02. I wonder if the office was closed over that period or a system was down for maintenance. If I saw spikes in memory or disk that corresponded to the drip in CPU, you can assume something was using those other resources and causing a drop, but when everything goes down, it just means that the system isn't gettting used. The disk on the rg-sql01 system isn't spiking exactly the same way as the memory & cpu, so there's a good chance (chance mind you) that any performance issues might not be disk related. However, notice that huge jump at the beginning of the month. Several disks were used more than they were for the rest of the month. That's the load on the server. What about the load on SQL Server itself? Next time.

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  • NHibernate 3.0 and FluentNHibernate, how to get up and running&hellip;.

    - by DesigningCode
    First up. Its actually really easy. I’m not very religious about my DB tech, I don’t really care, I just want something that works.  So I’m happy to consider all options if they provide an advantage, and recently I was considering jumping from NHibernate to EF 4.0.  However before ditching NHibernate and jumping to EF 4.0 I thought I should try the head version of NHibernates trunk and the Head version of FluentNHibernate. I currently have a “Repository / Unit of Work” Framework built up around these two techs.  All up it makes my life pretty simple for dealing with databases.   The problem is the current release of NHibernate + the Linq provider wasn’t too hot for our purposes.  Especially trying to plug it into older VB.NET code.   The Linq provider spat the dummy with VB.NET lambdas.  Mainly because in C# Query().Where(l => l.Name.Contains("x") || l.Name.Contains("y")).ToList(); is not the same as the VB.NET Query().Where(Function(l) l.Name.Contains("x") Or l.Name.Contains("y")).ToList VB.NET seems to spit out … well…. something different :-) so anyways… Compiling your own version of NHibernate and FluentNHibernate.  It’s actually pretty easy! First you’ll need to install tortisesvn NAnt and Git if you don’t already have them.  NHibernate first step, get the subversion trunk https://nhibernate.svn.sourceforge.net/svnroot/nhibernate/trunk/ into a directory somewhere.  eg \thirdparty\nhibernate Then use NAnt to build it.   (if you open the .sln it will show errors in that  AssemblyInfo.cs doesn’t exist ) to build it, there is a .txt document with sample command line build instructions,  I simply used :- NAnt -D:project.config=release clean build >output-release-build.log *wait* *wait* *wait* and ta da, you will have a bin directory with all the release dlls. FluentNHibernate This was pretty simple. there’s instructions here :- http://wiki.fluentnhibernate.org/Getting_started#Installation basically, with git, create a directory, and you issue the command git clone git://github.com/jagregory/fluent-nhibernate.git and wait, and soon enough you have the source. Now, from the bin directory that NHibernate spit out, take everything and dump it into the subdirectory “fluent-nhibernate\tools\NHibernate” Now, to build, you can use rake….which a ruby build system, however you can also just open the solution and build.   Which is what I did.  I had a few problems with the references which I simply re-added using the new ones.  Once built, I just took all the NHibnerate dlls, and the fluent ones and replaced my existing NHibernate / Fluent and killed off the old linq project. All I had to change is the places that used  .Linq<T>  and replace them with .Query<T>  (which was easy as I had wrapped it already to isolate my code from such changes) and hey presto, everything worked.  Even the VB.NET linq calls. I need to do some more testing as I’ve only done basic smoke tests, but its all looking pretty good, so for now, I will stick to NHibernate!

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  • SQL SERVER – Select the Most Optimal Backup Methods for Server

    - by pinaldave
    Backup and Restore are very interesting concepts and one should be very much with the concept if you are dealing with production database. One never knows when a natural disaster or user error will surface and the first thing everybody wants is to get back on point in time when things were all fine. Well, in this article I have attempted to answer a few of the common questions related to Backup methodology. How to Select a SQL Server Backup Type In order to select a proper SQL Server backup type, a SQL Server administrator needs to understand the difference between the major backup types clearly. Since a picture is worth a thousand words, let me offer it to you below. Select a Recovery Model First The very first question that you should ask yourself is: Can I afford to lose at least a little (15 min, 1 hour, 1 day) worth of data? Resist the temptation to save it all as it comes with the overhead – majority of businesses outside finances can actually afford to lose a bit of data. If your answer is YES, I can afford to lose some data – select a SIMPLE (default) recovery model in the properties of your database, otherwise you need to select a FULL recovery model. The additional advantage of the Full recovery model is that it allows you to restore the data to a specific point in time vs to only last backup time in the Simple recovery model, but it exceeds the scope of this article Backups in SIMPLE Recovery Model In SIMPLE recovery model you can select to do just Full backups or Full + Differential. Full Backup This is the simplest type of backup that contains all information needed to restore the database and should be your first choice. It is often sufficient for small databases, but note that it makes a big impact on the performance of your database Full + Differential Backup After Full, Differential backup picks up all of the changes since the last Full backup. This means if you made Full, Diff, Diff backup – the last Diff backup contains all of the changes and you don’t need the previous Differential backup. Differential backup is obviously smaller and carries less performance overhead Backups in FULL Recovery Model In FULL recovery model you can select Full + Transaction Log or Full + Differential + Transaction Log backup. You have to create Transaction Log backup, because at that time the log is being truncated. Otherwise your Transaction Log will grow uncontrollably. Full + Transaction Log Backup You would always need to perform a Full backup first. Then a series of Transaction log backup. Note that (in contrast to Differential) you need ALL transactions to log since the last Full of Diff backup to properly restore. Transaction log backups have the smallest performance overhead and can be performed often. Full + Differential + Transaction Log Backup If you want to ease the performance overhead on your server, you can replace some of the Full backup in the previous scenario with Differential. You restore scenario would start from Full, then the Last Differential, then all of the remaining transactions log backups Typical backup Scenarios You may say “Well, it is all nice – give me the examples now”. As you may already know, my favorite SQL backup software is SQLBackupAndFTP. If you go to Advanced Backup Schedule form in this program and click “Load a typical backup plan…” link, it will give you these scenarios that I think are quite common – see the image below. The Simplest Way to Schedule SQL Backups I hate to repeat myself, but backup scheduling in SQL agent leaves a lot to be desired. I do not know the simple way to schedule your SQL server backups than in SQLBackupAndFTP – see the image below. The whole backup scheduling with compression, encryption and upload to a Network Folder / HDD / NAS Drive / FTP / Dropbox / Google Drive / Amazon S3 takes just a few minutes – see my previous post for the review. Final Words This post offered an explanation for major backup types only. For more complicated scenarios or to research other options as usually go to MSDN. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Backup and Restore, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Managing Scripts in Oracle SQL Developer

    - by thatjeffsmith
    You backup your databases, right? You backup you home computer – your media collection, tax documents, bank accounts, etc, right? You backup your handy-dandy SQL scripts, right? Ok, now that I’ve got your head nodding, I want to answer a question I get every so often: How can I manage my scripts in SQL Developer? This is an interesting question. First, it assumes that one SHOULD manage their scripts in their IDE. Now, what I think the question generally gets around to is, how can we: Navigate to our scripts Open them Execute them What a good IDE should have is an interface to your existing Version Control System (VCS.) SQL Developer supports out-of-the-box both Subversion and Git. You can also download an extension via check-for-updates to get support for CVS. Now, what I’m about to show you COULD be done without versioning and controlling your scripts – but I want to ask you why you wouldn’t want to do this? So, I’m going to proceed and assume that you do INDEED version your scripts already. Seeing what scripts you’ve already got in your repository This is very straightforward – just open the Team Versions panel. Then connect to your repository. Shows you the files in your source control system. Now, I could ‘preview’ said file right away. If I open the file from here, we get a temp file copy down from the server to the local machine. This is a local temp copy of the controlled script – I can read/execute, but not write to it. And that might be all you need. But, if your script calls other scripts, then you’re going to want to check out the server copy of your stuff down your local SVN working copy directory. That way when your script calls another script – you’re executing the PRODUCTION APPROVED copies of said scripts. And if you do SPOOL or other file I/O stuff, it will work as expected. To get to those said client copies of your scripts… Enter the Files Panel The Files panel is accessible from the View menu. You can get to your files, one of two ways. If you’ve touched the file recently, you can see it under the Recent tree. Otherwise, you can navigate to your local ‘checked out’ copies of your script(s). Open your local copies, see what’s changed, etc. And I can access the change history and see what’s been touched… What changes am I going to ‘push out’ if I commit this back to the server? Most of us work on teams, yes? This panel also gives me a heads up if someone else is making changes to the same file. I can see the ‘incoming’ changes as well. To Sum It Up… If I want to get a script to run: do a full get to your local directory open the script(s) The files panel will tell you if your local copy is out of date from the server and if you have made local changes you’ve forgotten to commit back up to the server and your fellow teammates. Now, if you’re the selfish type and don’t want to share, that’s fine. But you should still be backing up your scripts, and you can still use the Files panel to manage your scripts.

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  • Normalisation and 'Anima notitia copia' (Soul of the Database)

    - by Phil Factor
    (A Guest Editorial for Simple-Talk) The other day, I was staring  at the sys.syslanguages  table in SQL Server with slightly-raised eyebrows . I’d just been reading Chris Date’s  interesting book ‘SQL and Relational Theory’. He’d made the point that you’re not necessarily doing relational database operations by using a SQL Database product.  The same general point was recently made by Dino Esposito about ASP.NET MVC.  The use of ASP.NET MVC doesn’t guarantee you a good application design: It merely makes it possible to test it. The way I’d describe the sentiment in both cases is ‘you can hit someone over the head with a frying-pan but you can’t call it cooking’. SQL enables you to create relational databases. However,  even if it smells bad, it is no crime to do hideously un-relational things with a SQL Database just so long as it’s necessary and you can tell the difference; not only that but also only if you’re aware of the risks and implications. Naturally, I’ve never knowingly created a database that Codd would have frowned at, but around the edges are interfaces and data feeds I’ve written  that have caused hissy fits amongst the Normalisation fundamentalists. Part of the problem for those who agonise about such things  is the misinterpretation of Atomicity.  An atomic value is one for which, in the strange virtual universe you are creating in your database, you don’t have any interest in any of its component parts.  If you aren’t interested in the electrons, neutrinos,  muons,  or  taus, then  an atom is ..er.. atomic. In the same way, if you are passed a JSON string or XML, and required to store it in a database, then all you need to do is to ask yourself, in your role as Anima notitia copia (Soul of the database) ‘have I any interest in the contents of this item of information?’.  If the answer is ‘No!’, or ‘nequequam! Then it is an atomic value, however complex it may be.  After all, you would never have the urge to store the pixels of images individually, under the misguided idea that these are the atomic values would you?  I would, of course,  ask the ‘Anima notitia copia’ rather than the application developers, since there may be more than one application, and the applications developers may be designing the application in the absence of full domain knowledge, (‘or by the seat of the pants’ as the technical term used to be). If, on the other hand, the answer is ‘sure, and we want to index the XML column’, then we may be in for some heavy XML-shredding sessions to get to store the ‘atomic’ values and ensure future harmony as the application develops. I went back to looking at the sys.syslanguages table. It has a months column with the months in a delimited list January,February,March,April,May,June,July,August,September,October,November,December This is an ordered list. Wicked? I seem to remember that this value, like shortmonths and days, is treated as a ‘thing’. It is merely passed off to an external  C++ routine in order to format a date in a particular language, and never accessed directly within the database. As far as the database is concerned, it is an atomic value.  There is more to normalisation than meets the eye.

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  • SQL SERVER – How to Roll Back SQL Server Database Changes

    - by Pinal Dave
    In a perfect scenario, no unexpected and unplanned changes occur. There are no unpleasant surprises, no inadvertent changes. However, even with all precautions and testing, there is sometimes a need to revert a structure or data change. One of the methods that can be used in this situation is to use an older database backup that has the records or database object structure you want to revert to. For this method, you have to have the adequate full database backup and a tool that will help you with comparison and synchronization is preferred. In this article, we will focus on another method: rolling back the changes. This can be done by using: An option in SQL Server Management Studio T-SQL, or ApexSQL Log The first two solutions have been described in this article The disadvantages of these methods are that you have to know when exactly the change you want to revert happened and that all transactions on the database executed in a specific time range are rolled back – the ones you want to undo and the ones you don’t. How to easily roll back SQL Server database changes using ApexSQL Log? The biggest challenge is to roll back just specific changes, not all changes that happened in a specific time range. While SQL Server Management Studio option and T-SQL read and roll forward all transactions in the transaction log files, I will show you a solution that finds and scripts only the specific changes that match your criteria. Therefore, you don’t need to worry about all other database changes that you don’t want to roll back. ApexSQL Log is a SQL Server disaster recovery tool that reads transaction logs and provides a wide range of filters that enable you to easily rollback only specific data changes. First, connect to the online database where you want to roll back the changes. Once you select the database, ApexSQL Log will show its recovery model. Note that changes can be rolled back even for a database in the Simple recovery model, when no database and transaction log backups are available. However, ApexSQL Log achieves best results when the database is in the Full recovery model and you have a chain of subsequent transaction log backups, back to the moment when the change occurred. In this example, we will use only the online transaction log. In the next step, use filters to read only the transactions that happened in a specific time range. To remove noise, it’s recommended to use as many filters as possible. Besides filtering by the time of the transaction, ApexSQL Log can filter by the operation type: Table name: As well as transaction state (committed, aborted, running, and unknown), name of the user who committed the change, specific field values, server process IDs, and transaction description. You can select only the tables affected by the changes you want to roll back. However, if you’re not certain which tables were affected, you can leave them all selected and once the results are shown in the main grid, analyze them to find the ones you to roll back. When you set the filters, you can select how to present the results. ApexSQL Log can automatically create undo or redo scripts, export the transactions into an XML, HTML, CSV, SQL, or SQL Bulk file, and create a batch file that you can use for unattended transaction log reading. In this example, I will open the results in the grid, as I want to analyze them before rolling back the transactions. The results contain information about the transaction, as well as who and when made it. For UPDATEs, ApexSQL Log shows both old and new values, so you can easily see what has happened. To create an UNDO script that rolls back the changes, select the transactions you want to roll back and click Create undo script in the menu. For the DELETE statement selected in the screenshot above, the undo script is: INSERT INTO [Sales].[PersonCreditCard] ([BusinessEntityID], [CreditCardID], [ModifiedDate]) VALUES (297, 8010, '20050901 00:00:00.000') When it comes to rolling back database changes, ApexSQL Log has a big advantage, as it rolls back only specific transactions, while leaving all other transactions that occurred at the same time range intact. That makes ApexSQL Log a good solution for rolling back inadvertent data and schema changes on your SQL Server databases. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: ApexSQL

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  • ArchBeat Link-o-Rama for 2012-06-26

    - by Bob Rhubart
    Software Architecture for High Availability in the Cloud | Brian Jimerson Brian Jimerson looks at the paradigm shifts from machine-based architectures to cloud-based architectures when designing fault tolerance, and how enterprise applications need to be engineered to ensure the highest level of availability in the cloud. SOA, Cloud & Service Technology Symposium 2012 London - Special Oracle Discount Registration is now open for one of the premier SOA, Cloud, and Service Technology events. Once again, the Oracle community is well-represented in the session schedule. And now you can save on registration with a special Oracle discount code. Progress 4GL and DB to Oracle and cloud | Tom Laszewski "Getting from client/server based 4GLs and databases where the 4GL is tightly linked to the database to Oracle and the cloud is not easy," says cloud migration expert Tom Laszewski. "The least risky and expensive option...is to use the Progress OpenEdge DataServer for Oracle." Embrace 'big data' now or fall behind the competition, analyst warns | TechTarget TechTarget's Mark Brunelli's story says, in essence, that Big Data is not your fathers Business Intelligence. Calculating the Size (in Bytes and MB) of a Oracle Coherence Cache | Ricardo Ferreira Ferreira illustrates a programmatic way to use the Oracle Coherence API to calculate the total size of a specific cache that resides in the data grid. WebCenter Portal Tutorial Part 7: Integrating Discussions and Link service | Yannick Ongena The latest chapter in Oracle ACE Yannick Ongena's ongoing series. How to Setup JDeveloper workspace for ADF Fusion Applications to run Business Component Tester? | Jack Desai Helpful technical tips from yet another member of the Oracle Fusion Middleware Architecture Team. Big Data for the Enterprise; Software Architecture for High Availability in the Cloud; Why Cloud Computing is a Paradigm Shift - And Why It Isn't This week on the OTN Solution Architect Homepage, along with an updated events list and this weeks list of selected community blog posts. Worst Practices for Big Data | Dain Hansen Dain Hansen shares some insight on what NOT to do if you want to captialize on Big Data. Free Virtual Developer Day - Oracle Fusion Development | Grant Ronald "The online conference will include seminars, hands-on lab and live chats with our technical staff including me!" says Grant Ronald. "And the best bit, it doesn't cost you a single penny. It's free and available right on your desktop." Penguin is Getting Ready for Oracle OpenWorld 2012 | Zeynep Koch Linux fan? Check out Zeynep Koch's post for a list of Linux-based sessions at Oracle OpenWorld 2012 in San Francisco. Amazon Web Services (AWS) Autoscaling | Frank Munz "Autoscaling on AWS can only be configured with lengthy commands from the command line but not from the web cased AWS console," says Frank Munz. "Getting all the parameters right can be tricky." He demonstrates one easy example in this video. Oracle Fusion Applications Design Patterns Now Available For Developers | Ultan O'Broin "These Oracle Fusion Applications UX Design Patterns, or blueprints, enable Oracle applications developers and system implementers everywhere to leverage professional usability insight," says O'Broin. How Much Data Is Created Every Minute? [INFOGRAPHIC] | Mashable Explaining what the "Big" in Big Data really means -- and it's more than a little mind-boggling. Thought for the Day "Real, though miniature, Turing Tests are happening all the time, every day, whenever a person puts up with stupid computer software." — Jaron Lanier Source: SoftwareQuotes.com

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  • ResourceSerializable: an alternate to ORM and ActiveRecord

    - by Levi Morrison
    A few opinionated reasons I don't like the traditional ORM and ActiveRecord patterns: They work only with a database. Sometimes I'm dealing with objects from an API and other objects from a database. All the implementations I have seen don't allow for that. Feel free to clue me in if I'm wrong on this. They are brittle. Changes in the database will likely break your implemenation. Some implementations can help reduce this, but a few of the ones I've seen don't. Their very design is influenced by the database. If I want to switch to using an API, I'll have to redesign the object to get it to work (likely). It seems to violate the single-responsibility pattern. They know what they are and how they act, but they also know how they are created, destroyed and saved? Seems a bit much. What about an approach that is somewhat more familiar in PHP: implementing an interface? In php 5.4, we'll have the JsonSerializable interface that defines the data to be json_encoded, so users will become accustomed to this type of thing. What if there was a ResourceSerializable interface? This is still an ORM by name, but certainly not by tradition. interface ResourceSerializable { /** * Returns the id that identifies the resource. */ function resourceId(); /** * Returns the 'type' of the resource. */ function resourceType(); /** * Returns the data to be serialized. */ function resourceSerialize(); } Things might be poorly named, I'll take suggestions. Notes: ResourceId will work for API's and databases. As long as your primary key in the database is the same as the resource ID in the API, there is no conflict. All of the API's I've worked with have a unique ID for the resource, so I don't see any issues there. ResourceType is the group or type associated with the resource. You can use this to map the resource to an API call or a database table. If the ResourceType was person, it could map to /api/1/person/{resourceId} and the table persons (or people, if it's smart enough). resourceSerialize() returns the data to be stored. Keys would identify API parameters and database table columns. This also seems easier to test than ActiveRecord / Orm implemenations. I haven't done much automated testing on traditional ActiveRecord/ORM implemenations, so this is merely a guess. But it seems that I being able to create objects independently of the library helps me. I don't have to use load() to get an existing resource, I can simply create one and set all the right properties. This is not so easy in the ActiveRecord / Orm implemenations I've dealt with. Downsides: You need another object to serialize it. This also means you have more code in general as you have to use more objects. You have to map resource types to API calls and database tables. This is even more work, but some ORMs and ActiveRecord implementations require you to map objects to table names anyway. Are there other downsides that you see? Does this seem feasible to you? How would you improve it? Note: I almost asked this on StackOverflow because it might be too vague for their standards, but I'm still not really familiar with programmers.stackexchange.com, so please help me improve my question if it doesn't shape up to standards here.

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  • Death March

    - by Nick Harrison
    It is a horrible sight to watch a project fail. There are few things as bad. Watching a project fail regardless of the reason is almost like sitting in a room with a "Dementor" from Harry Potter. It will literally suck all of the life and joy out of the room. Nearly every project that I have seen fail has failed because of political challenges or management challenges. Sometimes there are technical challenges that bring a project to its knees, but usually projects fail for less technical reasons. Here a few observations about projects failing for political reasons. Both the client and the consultants have to be committed to seeing the project succeed. Put simply, you cannot solve a problem when the primary stake holders do not truly want it solved. This could come from a consultant being more interested in extended the engagement. It could come from a client being afraid of what will happen to them once the problem is solved. It could come from disenfranchised stake holders. Sometimes a project is beset on all sides. When you find yourself working on a project that has this kind of threat, do all that you can to constrain the disruptive influences of the bad apples. If their influence cannot be constrained, you truly have no choice but to move on to a new project. Tough choices have to be made to make a project successful. These choices will affect everyone involved in the project. These choices may involve users not getting a change request through that they want. Developers may not get to use the tools that they want. Everyone may have to put in more hours that they originally planned. Steps may be skipped. Compromises will be made, but if everyone stays committed to the end goal, you can still be successful. If individuals start feeling disgruntled or resentful of the compromises reached, the project can easily be derailed. When everyone is not working towards a common goal, it is like driving with one foot on the break and one foot on the accelerator. Not only will you not get to where you are planning, you will also damage the car and possibly the passengers as well.   It is important to always keep the end result in mind. Regardless of the development methodology being followed, the end goal is not comprehensive documentation. In all cases, it is working software. Comprehensive documentation is nice but useless if the software doesn't work.   You can never get so distracted by the next goal that you fail to meet the current goal. Most projects are ultimately marathons. This means that the pace must be sustainable. Regardless of the temptations, you cannot burn the team alive. Processes will fail. Technology will get outdated. Requirements will change, but your people will adapt and learn and grow. If everyone on the team from the most senior analyst to the most junior recruit trusts and respects each other, there is no challenge that they cannot overcome. When everyone involved faces challenges with the attitude "This is my project and I will not let it fail" "You are my teammate and I will not let you fail", you will in fact not fail. When you find a team that embraces this attitude, protect it at all cost. Edward Yourdon wrote a book called Death March. In it, he included a graph for categorizing Death March project types based on the Happiness of the Team and the Chances of Success.   Chances are we have all worked on Death March projects. We will all most likely work on more Death March projects in the future. To a certain extent, they seem to be inevitable, but they should never be suicide or ugly. Ideally, they can all be "Mission Impossible" where everyone works hard, has fun, and knows that there is good chance that they will succeed. If you are ever lucky enough to work on such a project, you will know that sense of pride that comes from the eventual success. You will recognize a profound bond with the team that you worked with. Chances are it will change your life or at least your outlook on life. If you have not already read this book, get a copy and study it closely. It will help you survive and make the most out of your next Death March project.

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  • Some non-generic collections

    - by Simon Cooper
    Although the collections classes introduced in .NET 2, 3.5 and 4 cover most scenarios, there are still some .NET 1 collections that don't have generic counterparts. In this post, I'll be examining what they do, why you might use them, and some things you'll need to bear in mind when doing so. BitArray System.Collections.BitArray is conceptually the same as a List<bool>, but whereas List<bool> stores each boolean in a single byte (as that's what the backing bool[] does), BitArray uses a single bit to store each value, and uses various bitmasks to access each bit individually. This means that BitArray is eight times smaller than a List<bool>. Furthermore, BitArray has some useful functions for bitmasks, like And, Xor and Not, and it's not limited to 32 or 64 bits; a BitArray can hold as many bits as you need. However, it's not all roses and kittens. There are some fundamental limitations you have to bear in mind when using BitArray: It's a non-generic collection. The enumerator returns object (a boxed boolean), rather than an unboxed bool. This means that if you do this: foreach (bool b in bitArray) { ... } Every single boolean value will be boxed, then unboxed. And if you do this: foreach (var b in bitArray) { ... } you'll have to manually unbox b on every iteration, as it'll come out of the enumerator an object. Instead, you should manually iterate over the collection using a for loop: for (int i=0; i<bitArray.Length; i++) { bool b = bitArray[i]; ... } Following on from that, if you want to use BitArray in the context of an IEnumerable<bool>, ICollection<bool> or IList<bool>, you'll need to write a wrapper class, or use the Enumerable.Cast<bool> extension method (although Cast would box and unbox every value you get out of it). There is no Add or Remove method. You specify the number of bits you need in the constructor, and that's what you get. You can change the length yourself using the Length property setter though. It doesn't implement IList. Although not really important if you're writing a generic wrapper around it, it is something to bear in mind if you're using it with pre-generic code. However, if you use BitArray carefully, it can provide significant gains over a List<bool> for functionality and efficiency of space. OrderedDictionary System.Collections.Specialized.OrderedDictionary does exactly what you would expect - it's an IDictionary that maintains items in the order they are added. It does this by storing key/value pairs in a Hashtable (to get O(1) key lookup) and an ArrayList (to maintain the order). You can access values by key or index, and insert or remove items at a particular index. The enumerator returns items in index order. However, the Keys and Values properties return ICollection, not IList, as you might expect; CopyTo doesn't maintain the same ordering, as it copies from the backing Hashtable, not ArrayList; and any operations that insert or remove items from the middle of the collection are O(n), just like a normal list. In short; don't use this class. If you need some sort of ordered dictionary, it would be better to write your own generic dictionary combining a Dictionary<TKey, TValue> and List<KeyValuePair<TKey, TValue>> or List<TKey> for your specific situation. ListDictionary and HybridDictionary To look at why you might want to use ListDictionary or HybridDictionary, we need to examine the performance of these dictionaries compared to Hashtable and Dictionary<object, object>. For this test, I added n items to each collection, then randomly accessed n/2 items: So, what's going on here? Well, ListDictionary is implemented as a linked list of key/value pairs; all operations on the dictionary require an O(n) search through the list. However, for small n, the constant factor that big-o notation doesn't measure is much lower than the hashing overhead of Hashtable or Dictionary. HybridDictionary combines a Hashtable and ListDictionary; for small n, it uses a backing ListDictionary, but switches to a Hashtable when it gets to 9 items (you can see the point it switches from a ListDictionary to Hashtable in the graph). Apart from that, it's got very similar performance to Hashtable. So why would you want to use either of these? In short, you wouldn't. Any gain in performance by using ListDictionary over Dictionary<TKey, TValue> would be offset by the generic dictionary not having to cast or box the items you store, something the graphs above don't measure. Only if the performance of the dictionary is vital, the dictionary will hold less than 30 items, and you don't need type safety, would you use ListDictionary over the generic Dictionary. And even then, there's probably more useful performance gains you can make elsewhere.

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