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  • Always send certain values with an ajax request/post

    - by DZittersteyn
    I'm building a system that displays a list of user, and on selection of a user requests some form of password. These values are saved in a hidden field on the page, and need to be sent with every request as a form of authentication. (I'm aware of the MITM-vulnerability that lies herein, but it's a very low-key system, so security is not a large concern). Now I need to send these values with each and every request, to auth the currently 'logged in' user. I'd like to automate this, via ajaxSetup, however i'm running into some issues. My first try was: init_user_auth: function(){ $.ajaxSetup({ data: { 'user' : site_user.selected_user_id(), 'passcode': site_user.selected_user_pc(), 'barcode' : site_user.selected_user_bc() } }); }, However, as I should have known, this reads the values once, at the time of the call to ajaxSetup, and never rereads them. What I need is a way to actually call the functions every time an ajax-call is made. I'm currently trying to understand what is happening here: https://groups.google.com/forum/?fromgroups=#!topic/jquery-dev/OBcEfgvTJ9I, however through the flamewar and very low-level stuff going on there, I'm not exactly sure I get what is going on. Is this the way to proceed, or should I just face facts and manually add login-info to each ajax-call?

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  • How to detect iPhone movement in space using accelerometer ?

    - by super_tomtom
    Hi ! I am trying to make an application that would detect what kind of shape you made with your iPhone using accelerometer. As an example, if you draw a circle with your hand holding the iPhone, the app would be able to redraw it on the screen. This could also work with squares, or even more complicated shapes. The only example of application I've seen doing such a thing is AirPaint (http://vimeo.com/2276713), but it doesn't seems to be able to do it in real time. My first try is to apply a low-pass filter on the X and Y parameters from the accelerometer, and to make a pointer move toward these values, proportionally to the size of the screen. But this is clearly not enought, I have a very low accuracy, and if I shake the device it also makes the pointer move... Any ideas about that ? Do you think accelerometer data is enought to do it ? Or should I consider using other data, such as the compass ? Thanks in advance !

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  • passing xml to a webservice

    - by Neale
    I have a simple web service that will have one method: DoTransactions(xlm) Now the reason that i am using XML as a parameter is due to the fact that the parameters will often change. So for example it could be: <payload> <userId>1234</userid> <partnerId>ptn654</partnerId> </payload> OR <payload> <partnerId>ptn654</partnerId> <items> <item1> <cost>10</cost> <description>This is item 1</description> </item1> </items> </payload> As you can see the XML string will always change (this is due to a client request) Would it be better to rather pass in a string and parse the XML in the method or should is there a better way to do it. This web service will be used for varios different code languages.

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  • What is the fastest way to insert 100 000 records from one database to another?

    - by Pentium10
    I have a mobile application. My client has a large data set ~100.000 records. It's updated frequently. When we sync we need to copy from one database to another. I have attached the second database to the main, and run an insert into table select * from sync.table. This is extremely slow, it takes about 10 minutes I think. I noticed that the journal file gets increased step by step. How can I speed this up? EDITED 1 I have indexes off, and I have journal off. Using insert into table select * from sync.table it still takes 10 minutes. EDITED 2 If I run a query like select id,invitem,invid,cost from inventory where itemtype = 1 order by invitem limit 50 it takes 15-20 seconds. The table schema is: CREATE TABLE inventory ('id' INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, 'serverid' INTEGER NOT NULL DEFAULT 0, 'itemtype' INTEGER NOT NULL DEFAULT 0, 'invitem' VARCHAR, 'instock' FLOAT NOT NULL DEFAULT 0, 'cost' FLOAT NOT NULL DEFAULT 0, 'invid' VARCHAR, 'categoryid' INTEGER DEFAULT 0, 'pdacategoryid' INTEGER DEFAULT 0, 'notes' VARCHAR, 'threshold' INTEGER NOT NULL DEFAULT 0, 'ordered' INTEGER NOT NULL DEFAULT 0, 'supplier' VARCHAR, 'markup' FLOAT NOT NULL DEFAULT 0, 'taxfree' INTEGER NOT NULL DEFAULT 0, 'dirty' INTEGER NOT NULL DEFAULT 1, 'username' VARCHAR, 'version' INTEGER NOT NULL DEFAULT 15 ) Indexes are created like CREATE INDEX idx_inventory_categoryid ON inventory (pdacategoryid); CREATE INDEX idx_inventory_invitem ON inventory (invitem); CREATE INDEX idx_inventory_itemtype ON inventory (itemtype); I am wondering, the insert into ... select * from isn't the fastest built-in way to do massive data copy? EDITED 3 SQLite is serverless, so please stop voting a particular answer, because that is not the answer I'm sure.

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  • Oracle Query Optimization: Why is My Second Query Faster?

    - by Patrick Cuff
    I was having some performance issues with an Oracle query, so I downloaded a trial of the Quest SQL Optimizer for Oracle, which made some changes that dramatically improved the query's performance. I'm not exactly sure why the recommended query had such an improvement; can anyone provide an explanation? Before: SELECT t1.version_id, t1.id, t2.field1, t3.person_id, t2.id FROM table1 t1, table2 t2, table3 t3 WHERE t1.id = t2.id AND t1.version_id = t2.version_id AND t2.id = 123 AND t1.version_id = t3.version_id AND t1.VERSION_NAME <> 'AA' order by t1.id Plan Cost: 831 Elapsed Time: 00:00:21.40 Number of Records: 40,717 After: SELECT /*+ USE_NL_WITH_INDEX(t1) */ t1.version_id, t1.id, t2.field1, t3.person_id, t2.id FROM table2 t2, table3 t3, table1 t1 WHERE t1.id = t2.id + 0 AND t1.version_id = t2.version_id + 0 AND t2.id = 123 AND t1.version_id = t3.version_id + 0 AND t1.VERSION_NAME || '' <> 'AA' AND t3.version_id = t2.version_id + 0 order by t1.id Plan Cost: 686 Elapsed Time: 00:00:00.95 Number of Records: 40,717 Questions: Why does re-arranging the order of the tables in the FROM clause help? Why does adding + 0 to the WHERE clause comparisons help? Why does || '' <> 'AA' in the WHERE clause VERSION_NAME comparison help? Is this a more efficient way of handling possible nulls on this column?

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  • Windows Phone 8 xaml textblock binding format

    - by user2042227
    I would like to format a textblock which is binded to a value, to show "R" before the actuall value, is this possible, cause I cannot directly change the value? Thank you <ListBox x:Name="lstbundleListbox" Foreground="White" Height="320" HorizontalAlignment="Center"> <ListBox.ItemContainerStyle> <Style TargetType="ListBoxItem"> <Setter Property="HorizontalContentAlignment" Value="Center" /> </Style> </ListBox.ItemContainerStyle> <ListBox.ItemTemplate> <DataTemplate> <StackPanel> <TextBlock Text="{Binding name}" TextWrapping="Wrap" HorizontalAlignment="Center"/> <TextBlock Text="{Binding cost}" TextWrapping="Wrap" HorizontalAlignment="Center"/> </StackPanel> </DataTemplate> </ListBox.ItemTemplate> <ItemsControl.ItemsPanel> <ItemsPanelTemplate> <StackPanel Orientation="Vertical"/> </ItemsPanelTemplate> </ItemsControl.ItemsPanel> </ListBox> So I basically want the texblock to show R(cost)

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  • How do I compare 2 fields and return the lowest value of each record?

    - by BigRob
    I'm slowly learning access to make a database of products and suppliers for my parents' business. What i've got is a table of products indexed by our product reference and 2 more tables for 2 different suppliers that contains the suppliers product reference and price that links with our reference. I've made a query that performs a left outer join such that it returns a table of our products with each supplier's reference and price, i.e: Ref | Product Name | Supplier 1 Ref | Supplier 1 Price | Supplier 2 Ref | Supplier 2 Price Here's the query I used: SELECT Catalog.Ref, Catalog.[Product Name], Catalog.Price, [D Products].[Supplier Ref], [D Products].Cost, [GS Products].[Supplier Ref], [GS Products].Cost FROM ([Catalog] LEFT JOIN [D Products] ON Catalog.Ref = [D Products].Ref) LEFT JOIN [GS Products] ON Catalog.Ref = [GS Products].Ref; Not all products are available from both suppliers, hence the outer join. What I want to do (with a query?) is to take the table produced by the query above and simply show the product reference, cheapest supplier reference and cheapest supplier price, i.e: Ref | Cheapest Suppplier Ref | Cheapest Supplier Price Unfortunately my SQL knowledge isn't quite good enough to figure this out, but if anyone can help i'd really appreciate it. Thanks, Rob

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  • Java using generics with lists and interfaces

    - by MirroredFate
    Ok, so here is my problem: I have a list containing interfaces - List<Interface> a - and a list of interfaces that extend that interface: List<SubInterface> b. I want to set a = b. I do not wish to use addAll() or anything that will cost more memory as what I am doing is already very cost-intensive. I literally need to be able to say a = b. I have tried List<? extends Interface> a, but then I cannot add Interfaces to the list a, only the SubInterfaces. Any suggestions? EDIT I want to be able to do something like this: List<SubRecord> records = new ArrayList<SubRecord>(); //add things to records recordKeeper.myList = records; The class RecordKeeper is the one that contains the list of Interfaces (NOT subInterfaces) public class RecordKeeper{ public List<Record> myList; }

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  • Windows Azure: General Availability of Web Sites + Mobile Services, New AutoScale + Alerts Support, No Credit Card Needed for MSDN

    - by ScottGu
    This morning we released a major set of updates to Windows Azure.  These updates included: Web Sites: General Availability Release of Windows Azure Web Sites with SLA Mobile Services: General Availability Release of Windows Azure Mobile Services with SLA Auto-Scale: New automatic scaling support for Web Sites, Cloud Services and Virtual Machines Alerts/Notifications: New email alerting support for all Compute Services (Web Sites, Mobile Services, Cloud Services, and Virtual Machines) MSDN: No more credit card requirement for sign-up All of these improvements are now available to use immediately (note: some are still in preview).  Below are more details about them. Web Sites: General Availability Release of Windows Azure Web Sites I’m incredibly excited to announce the General Availability release of Windows Azure Web Sites. The Windows Azure Web Sites service is perfect for hosting a web presence, building customer engagement solutions, and delivering business web apps.  Today’s General Availability release means we are taking off the “preview” tag from the Free and Standard (formerly called reserved) tiers of Windows Azure Web Sites.  This means we are providing: A 99.9% monthly SLA (Service Level Agreement) for the Standard tier Microsoft Support available on a 24x7 basis (with plans that range from developer plans to enterprise Premier support) The Free tier runs in a shared compute environment and supports up to 10 web sites. While the Free tier does not come with an SLA, it works great for rapid development and testing and enables you to quickly spike out ideas at no cost. The Standard tier, which was called “Reserved” during the preview, runs using dedicated per-customer VM instances for great performance, isolation and scalability, and enables you to host up to 500 different Web sites within them.  You can easily scale your Standard instances on-demand using the Windows Azure Management Portal.  You can adjust VM instance sizes from a Small instance size (1 core, 1.75GB of RAM), up to a Medium instance size (2 core, 3.5GB of RAM), or Large instance (4 cores and 7 GB RAM).  You can choose to run between 1 and 10 Standard instances, enabling you to easily scale up your web backend to 40 cores of CPU and 70GB of RAM: Today’s release also includes general availability support for custom domain SSL certificate bindings for web sites running using the Standard tier. Customers will be able to utilize certificates they purchase for their custom domains and use either SNI or IP based SSL encryption. SNI encryption is available for all modern browsers and does not require an IP address.  SSL certificates can be used for individual sites or wild-card mapped across multiple sites (we charge extra for the use of a SSL cert – but the fee is per-cert and not per site which means you pay once for it regardless of how many sites you use it with).  Today’s release also includes the following new features: Auto-Scale support Today’s Windows Azure release adds preview support for Auto-Scaling web sites.  This enables you to setup automatic scale rules based on the activity of your instances – allowing you to automatically scale down (and save money) when they are below a CPU threshold you define, and automatically scale up quickly when traffic increases.  See below for more details. 64-bit and 32-bit mode support You can now choose to run your standard tier instances in either 32-bit or 64-bit mode (previously they only ran in 32-bit mode).  This enables you to address even more memory within individual web applications. Memory dumps Memory dumps can be very useful for diagnosing issues and debugging apps. Using a REST API, you can now get a memory dump of your sites, which you can then use for investigating issues in Visual Studio Debugger, WinDbg, and other tools. Scaling Sites Independently Prior to today’s release, all sites scaled up/down together whenever you scaled any site in a sub-region. So you may have had to keep your proof-of-concept or testing sites in a separate sub-region if you wanted to keep them in the Free tier. This will no longer be necessary.  Windows Azure Web Sites can now mix different tier levels in the same geographic sub-region. This allows you, for example, to selectively move some of your sites in the West US sub-region up to Standard tier when they require the features, scalability, and SLA of the Standard tier. Full pricing details on Windows Azure Web Sites can be found here.  Note that the “Shared Tier” of Windows Azure Web Sites remains in preview mode (and continues to have discounted preview pricing).  Mobile Services: General Availability Release of Windows Azure Mobile Services I’m incredibly excited to announce the General Availability release of Windows Azure Mobile Services.  Mobile Services is perfect for building scalable cloud back-ends for Windows 8.x, Windows Phone, Apple iOS, Android, and HTML/JavaScript applications.  Customers We’ve seen tremendous adoption of Windows Azure Mobile Services since we first previewed it last September, and more than 20,000 customers are now running mobile back-ends in production using it.  These customers range from startups like Yatterbox, to university students using Mobile Services to complete apps like Sly Fox in their spare time, to media giants like Verdens Gang finding new ways to deliver content, and telcos like TalkTalk Business delivering the up-to-the-minute information their customers require.  In today’s Build keynote, we demonstrated how TalkTalk Business is using Windows Azure Mobile Services to deliver service, outage and billing information to its customers, wherever they might be. Partners When we unveiled the source control and Custom API features I blogged about two weeks ago, we enabled a range of new scenarios, one of which is a more flexible way to work with third party services.  The following blogs, samples and tutorials from our partners cover great ways you can extend Mobile Services to help you build rich modern apps: New Relic allows developers to monitor and manage the end-to-end performance of iOS and Android applications connected to Mobile Services. SendGrid eliminates the complexity of sending email from Mobile Services, saving time and money, while providing reliable delivery to the inbox. Twilio provides a telephony infrastructure web service in the cloud that you can use with Mobile Services to integrate phone calls, text messages and IP voice communications into your mobile apps. Xamarin provides a Mobile Services add on to make it easy building cross-platform connected mobile aps. Pusher allows quickly and securely add scalable real-time messaging functionality to Mobile Services-based web and mobile apps. Visual Studio 2013 and Windows 8.1 This week during //build/ keynote, we demonstrated how Visual Studio 2013, Mobile Services and Windows 8.1 make building connected apps easier than ever. Developers building Windows 8 applications in Visual Studio can now connect them to Windows Azure Mobile Services by simply right clicking then choosing Add Connected Service. You can either create a new Mobile Service or choose existing Mobile Service in the Add Connected Service dialog. Once completed, Visual Studio adds a reference to Mobile Services SDK to your project and generates a Mobile Services client initialization snippet automatically. Add Push Notifications Push Notifications and Live Tiles are a key to building engaging experiences. Visual Studio 2013 and Mobile Services make it super easy to add push notifications to your Windows 8.1 app, by clicking Add a Push Notification item: The Add Push Notification wizard will then guide you through the registration with the Windows Store as well as connecting your app to a new or existing mobile service. Upon completion of the wizard, Visual Studio will configure your mobile service with the WNS credentials, as well as add sample logic to your client project and your mobile service that demonstrates how to send push notifications to your app. Server Explorer Integration In Visual Studio 2013 you can also now view your Mobile Services in the the Server Explorer. You can add tables, edit, and save server side scripts without ever leaving Visual Studio, as shown on the image below: Pricing With today’s general availability release we are announcing that we will be offering Mobile Services in three tiers – Free, Standard, and Premium.  Each tier is metered using a simple pricing model based on the # of API calls (bandwidth is included at no extra charge), and the Standard and Premium tiers are backed by 99.9% monthly SLAs.  You can elastically scale up or down the number of instances you have of each tier to increase the # of API requests your service can support – allowing you to efficiently scale as your business grows. The following table summarizes the new pricing model (full pricing details here):   You can find the full details of the new pricing model here. Build Conference Talks The //BUILD/ conference will be packed with sessions covering every aspect of developing connected applications with Mobile Services. The best part is that, even if you can’t be with us in San Francisco, every session is being streamed live. Be sure not to miss these talks: Mobile Services – Soup to Nuts — Josh Twist Building Cross-Platform Apps with Windows Azure Mobile Services — Chris Risner Connected Windows Phone Apps made Easy with Mobile Services — Yavor Georgiev Build Connected Windows 8.1 Apps with Mobile Services — Nick Harris Who’s that user? Identity in Mobile Apps — Dinesh Kulkarni Building REST Services with JavaScript — Nathan Totten Going Live and Beyond with Windows Azure Mobile Services — Kirill Gavrylyuk , Paul Batum Protips for Windows Azure Mobile Services — Chris Risner AutoScale: Dynamically scale up/down your app based on real-world usage One of the key benefits of Windows Azure is that you can dynamically scale your application in response to changing demand. In the past, though, you have had to either manually change the scale of your application, or use additional tooling (such as WASABi or MetricsHub) to automatically scale your application. Today, we’re announcing that AutoScale will be built-into Windows Azure directly.  With today’s release it is now enabled for Cloud Services, Virtual Machines and Web Sites (Mobile Services support will come soon). Auto-scale enables you to configure Windows Azure to automatically scale your application dynamically on your behalf (without any manual intervention) so you can achieve the ideal performance and cost balance. Once configured it will regularly adjust the number of instances running in response to the load in your application. Currently, we support two different load metrics: CPU percentage Storage queue depth (Cloud Services and Virtual Machines only) We’ll enable automatic scaling on even more scale metrics in future updates. When to use Auto-Scale The following are good criteria for services/apps that will benefit from the use of auto-scale: The service/app can scale horizontally (e.g. it can be duplicated to multiple instances) The service/app load changes over time If your app meets these criteria, then you should look to leverage auto-scale. How to Enable Auto-Scale To enable auto-scale, simply navigate to the Scale tab in the Windows Azure Management Portal for the app/service you wish to enable.  Within the scale tab turn the Auto-Scale setting on to either CPU or Queue (for Cloud Services and VMs) to enable Auto-Scale.  Then change the instance count and target CPU settings to configure the Auto-Scale ranges you want to maintain. The image below demonstrates how to enable Auto-Scale on a Windows Azure Web-Site.  I’ve configured the web-site so that it will run using between 1 and 5 VM instances.  The exact # used will depend on the aggregate CPU of the VMs using the 40-70% range I’ve configured below.  If the aggregate CPU goes above 70%, then Windows Azure will automatically add new VMs to the pool (up to the maximum of 5 instances I’ve configured it to use).  If the aggregate CPU drops below 40% then Windows Azure will automatically start shutting down VMs to save me money: Once you’ve turned auto-scale on, you can return to the Scale tab at any point and select Off to manually set the number of instances. Using the Auto-Scale Preview With today’s update you can now, in just a few minutes, have Windows Azure automatically adjust the number of instances you have running  in your apps to keep your service performant at an even better cost. Auto-scale is being released today as a preview feature, and will be free until General Availability. During preview, each subscription is limited to 10 separate auto-scale rules across all of the resources they have (Web sites, Cloud services or Virtual Machines). If you hit the 10 limit, you can disable auto-scale for any resource to enable it for another. Alerts and Notifications Starting today we are now providing the ability to configure threshold based alerts on monitoring metrics. This feature is available for compute services (cloud services, VM, websites and mobiles services). Alerts provide you the ability to get proactively notified of active or impending issues within your application.  You can define alert rules for: Virtual machine monitoring metrics that are collected from the host operating system (CPU percentage, network in/out, disk read bytes/sec and disk write bytes/sec) and on monitoring metrics from monitoring web endpoint urls (response time and uptime) that you have configured. Cloud service monitoring metrics that are collected from the host operating system (same as VM), monitoring metrics from the guest VM (from performance counters within the VM) and on monitoring metrics from monitoring web endpoint urls (response time and uptime) that you have configured. For Web Sites and Mobile Services, alerting rules can be configured on monitoring metrics from monitoring endpoint urls (response time and uptime) that you have configured. Creating Alert Rules You can add an alert rule for a monitoring metric by navigating to the Setting -> Alerts tab in the Windows Azure Management Portal. Click on the Add Rule button to create an alert rule. Give the alert rule a name and optionally add a description. Then pick the service which you want to define the alert rule on: The next step in the alert creation wizard will then filter the monitoring metrics based on the service you selected:   Once created the rule will show up in your alerts list within the settings tab: The rule above is defined as “not activated” since it hasn’t tripped over the CPU threshold we set.  If the CPU on the above machine goes over the limit, though, I’ll get an email notifying me from an Windows Azure Alerts email address ([email protected]). And when I log into the portal and revisit the alerts tab I’ll see it highlighted in red.  Clicking it will then enable me to see what is causing it to fail, as well as view the history of when it has happened in the past. Alert Notifications With today’s initial preview you can now easily create alerting rules based on monitoring metrics and get notified on active or impending issues within your application that require attention. During preview, each subscription is limited to 10 alert rules across all of the services that support alert rules. No More Credit Card Requirement for MSDN Subscribers Earlier this month (during TechEd 2013), Windows Azure announced that MSDN users will get Windows Azure Credits every month that they can use for any Windows Azure services they want. You can read details about this in my previous Dev/Test blog post. Today we are making further updates to enable an easier Windows Azure signup for MSDN users. MSDN users will now not be required to provide payment information (e.g. no credit card) during sign-up, so long as they use the service within the included monetary credit for the billing period. For usage beyond the monetary credit, they can enable overages by providing the payment information and remove the spending limit. This enables a super easy, one page sign-up experience for MSDN users.  Simply sign-up for your Windows Azure trial using the same Microsoft ID that you use to manage your MSDN account, then complete the one page sign-up form below and you will be able to spend your free monthly MSDN credits (up to $150 each month) on any Windows Azure resource for dev/test:   This makes it trivially easy for every MDSN customer to start using Windows Azure today.  If you haven’t signed up yet, I definitely recommend checking it out. Summary Today’s release includes a ton of great features that enable you to build even better cloud solutions.  If you don’t already have a Windows Azure account, you can sign-up for a free trial and start using all of the above features today.  Then visit the Windows Azure Developer Center to learn more about how to build apps with it. Hope this helps, Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

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  • eBooks on iPad vs. Kindle: More Debate than Smackdown

    - by andrewbrust
    When the iPad was presented at its San Francisco launch event on January 28th, Steve Jobs spent a significant amount of time explaining how well the device would serve as an eBook reader. He showed the iBooks reader application and iBookstore and laid down the gauntlet before Amazon and its beloved Kindle device. Almost immediately afterwards, criticism came rushing forth that the iPad could never beat the Kindle for book reading. The curious part of that criticism is that virtually no one offering it had actually used the iPad yet. A few weeks later, on April 3rd, the iPad was released for sale in the United States. I bought one on that day and in the few additional weeks that have elapsed, I’ve given quite a workout to most of its capabilities, including its eBook features. I’ve also spent some time with the Kindle, albeit a first-generation model, to see how it actually compares to the iPad. I had some expectations going in, but I came away with conclusions about each device that were more scenario-based than absolute. I present my findings to you here.   Vital Statistics Let’s start with an inventory of each device’s underlying technology. The iPad has a color, backlit LCD screen and an on-screen keyboard. It has a battery which, on a full charge, lasts anywhere from 6-10 hours. The Kindle offers a monochrome, reflective E Ink display, a physical keyboard and a battery that on my first gen loaner unit can go up to a week between charges (Amazon claims the battery on the Kindle 2 can last up to 2 weeks on a single charge). The Kindle connects to Amazon’s Kindle Store using a 3G modem (the technology and network vary depending on the model) that incurs no airtime service charges whatsoever. The iPad units that are on-sale today work over WiFi only. 3G-equipped models will be on sale shortly and will command a $130 premium over their WiFi-only counterparts. 3G service on the iPad, in the U.S. from AT&T, will be fee-based, with a 250MB plan at $14.99 per month and an unlimited plan at $29.99. No contract is required for 3G service. All these tech specs aside, I think a more useful observation is that the iPad is a multi-purpose Internet-connected entertainment device, while the Kindle is a dedicated reading device. The question is whether those differences in design and intended use create a clear-cut winner for reading electronic publications. Let’s take a look at each device, in isolation, now.   Kindle To me, what’s most innovative about the Kindle is its E Ink display. E Ink really looks like ink on a sheet of paper. It requires no backlight, it’s fully visible in direct sunlight and it causes almost none of the eyestrain that LCD-based computer display technology (like that used on the iPad) does. It’s really versatile in an all-around way. Forgive me if this sounds precious, but reading on it is really a joy. In fact, it’s a genuinely relaxing experience. Through the Kindle Store, Amazon allows users to download books (including audio books), magazines, newspapers and blog feeds. Books and magazines can be purchased either on a single-issue basis or as an annual subscription. Books, of course, are purchased singly. Oddly, blogs are not free, but instead carry a monthly subscription fee, typically $1.99. To me this is ludicrous, but I suppose the free 3G service is partially to blame. Books and magazine issues download quickly. Magazine and blog subscriptions cause new issues or posts to be pushed to your device on an automated basis. Available blogs include 9000-odd feeds that Amazon offers on the Kindle Store; unless I missed something, arbitrary RSS feeds are not supported (though there are third party workarounds to this limitation). The shopping experience is integrated well, has an huge selection, and offers certain graphical perks. For example, magazine and newspaper logos are displayed in menus, and book cover thumbnails appear as well. A simple search mechanism is provided and text entry through the physical keyboard is relatively painless. It’s very easy and straightforward to enter the store, find something you like and start reading it quickly. If you know what you’re looking for, it’s even faster. Given Kindle’s high portability, very reliable battery, instant-on capability and highly integrated content acquisition, it makes reading on whim, and in random spurts of downtime, very attractive. The Kindle’s home screen lists all of your publications, and easily lets you select one, then start reading it. Once opened, publications display in crisp, attractive text that is adjustable in size. “Turning” pages is achieved through buttons dedicated to the task. Notes can be recorded, bookmarks can be saved and pages can be saved as clippings. I am not an avid book reader, and yet I found the Kindle made it really fun, convenient and soothing to read. There’s something about the easy access to the material and the simplicity of the display that makes the Kindle seduce you into chilling out and reading page after page. On the other hand, the Kindle has an awkward navigation interface. While menus are displayed clearly on the screen, the method of selecting menu items is tricky: alongside the right-hand edge of the main display is a thin column that acts as a second display. It has a white background, and a scrollable silver cursor that is moved up or down through the use of the device’s scrollwheel. Picking a menu item on the main display involves scrolling the silver cursor to a position parallel to that menu item and pushing the scrollwheel in. This navigation technique creates a disconnect, literally. You don’t really click on a selection so much as you gesture toward it. I got used to this technique quickly, but I didn’t love it. It definitely created a kind of anxiety in me, making me feel the need to speed through menus and get to my destination document quickly. Once there, I could calm down and relax. Books are great on the Kindle. Magazines and newspapers much less so. I found the rendering of photographs, and even illustrations, to be unacceptably crude. For this reason, I expect that reading textbooks on the Kindle may leave students wanting. I found that the original flow and layout of any publication was sacrificed on the Kindle. In effect, browsing a magazine or newspaper was almost impossible. Reading the text of individual articles was enjoyable, but having to read this way made the whole experience much more “a la carte” than cohesive and thematic between articles. I imagine that for academic journals this is ideal, but for consumer publications it imposes a stripped-down, low-fidelity experience that evokes a sense of deprivation. In general, the Kindle is great for reading text. For just about anything else, especially activity that involves exploratory browsing, meandering and short-attention-span reading, it presents a real barrier to entry and adoption. Avid book readers will enjoy the Kindle (if they’re not already). It’s a great device for losing oneself in a book over long sittings. Multitaskers who are more interested in periodicals, be they online or off, will like it much less, as they will find compromise, and even sacrifice, to be palpable.   iPad The iPad is a very different device from the Kindle. While the Kindle is oriented to pages of text, the iPad orbits around applications and their interfaces. Be it the pinch and zoom experience in the browser, the rich media features that augment content on news and weather sites, or the ability to interact with social networking services like Twitter, the iPad is versatile. While it shares a slate-like form factor with the Kindle, it’s effectively an elegant personal computer. One of its many features is the iBook application and integration of the iBookstore. But it’s a multi-purpose device. That turns out to be good and bad, depending on what you’re reading. The iBookstore is great for browsing. It’s color, rich animation-laden user interface make it possible to shop for books, rather than merely search and acquire them. Unfortunately, its selection is rather sparse at the moment. If you’re looking for a New York Times bestseller, or other popular titles, you should be OK. If you want to read something more specialized, it’s much harder. Unlike the awkward navigation interface of the Kindle, the iPad offers a nearly flawless touch-screen interface that seduces the user into tinkering and kibitzing every bit as much as the Kindle lulls you into a deep, concentrated read. It’s a dynamic and interactive device, whereas the Kindle is static and passive. The iBook reader is slick and fun. Use the iPad in landscape mode and you can read the book in 2-up (left/right 2-page) display; use it in portrait mode and you can read one page at a time. Rather than clicking a hardware button to turn pages, you simply drag and wipe from right-to-left to flip the single or right-hand page. The page actually travels through an animated path as it would in a physical book. The intuitiveness of the interface is uncanny. The reader also accommodates saving of bookmarks, searching of the text, and the ability to highlight a word and look it up in a dictionary. Pages display brightly and clearly. They’re easy to read. But the backlight and the glare made me less comfortable than I was with the Kindle. The knowledge that completely different applications (including the Web and email and Twitter) were just a few taps away made me antsy and very tempted to task-switch. The knowledge that battery life is an issue created subtle discomfort. If the Kindle makes you feel like you’re in a library reading room, then the iPad makes you feel, at best, like you’re under fluorescent lights at a Barnes and Noble or Borders store. If you’re lucky, you’d be on a couch or at a reading table in the store, but you might also be standing up, in the aisles. Clearly, I didn’t find this conducive to focused and sustained reading. But that may have more to do with my own tendency to read periodicals far more than books, and my neurotic . And, truth be known, the book reading experience, when not explicitly compared to Kindle’s, was still pleasant. It is also important to point out that Kindle Store-sourced books can be read on the iPad through a Kindle reader application, from Amazon, specific to the device. This offered a less rich experience than the iBooks reader, but it was completely adequate. Despite the Kindle brand of the reader, however, it offered little in terms of simulating the reading experience on its namesake device. When it comes to periodicals, the iPad wins hands down. Magazines, even if merely scanned images of their print editions, read on the iPad in a way that felt similar to reading hard copy. The full color display, touch navigation and even the ability to render advertisements in their full glory makes the iPad a great way to read through any piece of work that is measured in pages, rather than chapters. There are many ways to get magazines and newspapers onto the iPad, including the Zinio reader, and publication-specific applications like the Wall Street Journal’s and Popular Science’s. The New York Times’ free Editors’ Choice application offers a Times Reader-like interface to a subset of the Gray Lady’s daily content. The completely Web-based but iPad-optimized Times Skimmer site (at www.nytimes.com/timesskimmer) works well too. Even conventional Web sites themselves can be read much like magazines, given the iPad’s ability to zoom in on the text and crop out advertisements on the margins. While the Kindle does have an experimental Web browser, it reminded me a lot of early mobile phone browsers, only in a larger size. For text-heavy sites with simple layout, it works fine. For just about anything else, it becomes more trouble than it’s worth. And given the way magazine articles make me think of things I want to look up online, I think that’s a real liability for the Kindle.   Summing Up What I came to realize is that the Kindle isn’t so much a computer or even an Internet device as it is a printer. While it doesn’t use physical paper, it still renders its content a page at a time, just like a laser printer does, and its output appears strikingly similar. You can read the rendered text, but you can’t interact with it in any way. That’s why the navigation requires a separate cursor display area. And because of the page-oriented rendering behavior, turning pages causes a flash on the display and requires a sometimes long pause before the next page is rendered. The good side of this is that once the page is generated, no battery power is required to display it. That makes for great battery life, optimal viewing under most lighting conditions (as long as there is some light) and low-eyestrain text-centric display of content. The Kindle is highly portable, has an excellent selection in its store and is refreshingly distraction-free. All of this is ideal for reading books. And iPad doesn’t offer any of it. What iPad does offer is versatility, variety, richness and luxury. It’s flush with accoutrements even if it’s low on focused, sustained text display. That makes it inferior to the Kindle for book reading. But that also makes it better than the Kindle for almost everything else. As such, and given that its book reading experience is still decent (even if not superior), I think the iPad will give Kindle a run for its money. True book lovers, and people on a budget, will want the Kindle. People with a robust amount of discretionary income may want both devices. Everyone else who is interested in a slate form factor e-reading device, especially if they also wish to have leisure-friendly Internet access, will likely choose the iPad exclusively. One thing is for sure: iPad has reduced Kindle’s market, and may have shifted its mass market potential to a mere niche play. If Amazon is smart, it will improve its iPad-based Kindle reader app significantly. It can then leverage the iPad channel as a significant market for the Kindle Store. After all, selling the eBooks themselves is what Amazon should care most about.

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  • Simplex Noise Help

    - by Alex Larsen
    Im Making A Minecraft Like Gae In XNA C# And I Need To Generate Land With Caves This Is The Code For Simplex I Have /// <summary> /// 1D simplex noise /// </summary> /// <param name="x"></param> /// <returns></returns> public static float Generate(float x) { int i0 = FastFloor(x); int i1 = i0 + 1; float x0 = x - i0; float x1 = x0 - 1.0f; float n0, n1; float t0 = 1.0f - x0 * x0; t0 *= t0; n0 = t0 * t0 * grad(perm[i0 & 0xff], x0); float t1 = 1.0f - x1 * x1; t1 *= t1; n1 = t1 * t1 * grad(perm[i1 & 0xff], x1); // The maximum value of this noise is 8*(3/4)^4 = 2.53125 // A factor of 0.395 scales to fit exactly within [-1,1] return 0.395f * (n0 + n1); } /// <summary> /// 2D simplex noise /// </summary> /// <param name="x"></param> /// <param name="y"></param> /// <returns></returns> public static float Generate(float x, float y) { const float F2 = 0.366025403f; // F2 = 0.5*(sqrt(3.0)-1.0) const float G2 = 0.211324865f; // G2 = (3.0-Math.sqrt(3.0))/6.0 float n0, n1, n2; // Noise contributions from the three corners // Skew the input space to determine which simplex cell we're in float s = (x + y) * F2; // Hairy factor for 2D float xs = x + s; float ys = y + s; int i = FastFloor(xs); int j = FastFloor(ys); float t = (float)(i + j) * G2; float X0 = i - t; // Unskew the cell origin back to (x,y) space float Y0 = j - t; float x0 = x - X0; // The x,y distances from the cell origin float y0 = y - Y0; // For the 2D case, the simplex shape is an equilateral triangle. // Determine which simplex we are in. int i1, j1; // Offsets for second (middle) corner of simplex in (i,j) coords if (x0 > y0) { i1 = 1; j1 = 0; } // lower triangle, XY order: (0,0)->(1,0)->(1,1) else { i1 = 0; j1 = 1; } // upper triangle, YX order: (0,0)->(0,1)->(1,1) // A step of (1,0) in (i,j) means a step of (1-c,-c) in (x,y), and // a step of (0,1) in (i,j) means a step of (-c,1-c) in (x,y), where // c = (3-sqrt(3))/6 float x1 = x0 - i1 + G2; // Offsets for middle corner in (x,y) unskewed coords float y1 = y0 - j1 + G2; float x2 = x0 - 1.0f + 2.0f * G2; // Offsets for last corner in (x,y) unskewed coords float y2 = y0 - 1.0f + 2.0f * G2; // Wrap the integer indices at 256, to avoid indexing perm[] out of bounds int ii = i % 256; int jj = j % 256; // Calculate the contribution from the three corners float t0 = 0.5f - x0 * x0 - y0 * y0; if (t0 < 0.0f) n0 = 0.0f; else { t0 *= t0; n0 = t0 * t0 * grad(perm[ii + perm[jj]], x0, y0); } float t1 = 0.5f - x1 * x1 - y1 * y1; if (t1 < 0.0f) n1 = 0.0f; else { t1 *= t1; n1 = t1 * t1 * grad(perm[ii + i1 + perm[jj + j1]], x1, y1); } float t2 = 0.5f - x2 * x2 - y2 * y2; if (t2 < 0.0f) n2 = 0.0f; else { t2 *= t2; n2 = t2 * t2 * grad(perm[ii + 1 + perm[jj + 1]], x2, y2); } // Add contributions from each corner to get the final noise value. // The result is scaled to return values in the interval [-1,1]. return 40.0f * (n0 + n1 + n2); // TODO: The scale factor is preliminary! } public static float Generate(float x, float y, float z) { // Simple skewing factors for the 3D case const float F3 = 0.333333333f; const float G3 = 0.166666667f; float n0, n1, n2, n3; // Noise contributions from the four corners // Skew the input space to determine which simplex cell we're in float s = (x + y + z) * F3; // Very nice and simple skew factor for 3D float xs = x + s; float ys = y + s; float zs = z + s; int i = FastFloor(xs); int j = FastFloor(ys); int k = FastFloor(zs); float t = (float)(i + j + k) * G3; float X0 = i - t; // Unskew the cell origin back to (x,y,z) space float Y0 = j - t; float Z0 = k - t; float x0 = x - X0; // The x,y,z distances from the cell origin float y0 = y - Y0; float z0 = z - Z0; // For the 3D case, the simplex shape is a slightly irregular tetrahedron. // Determine which simplex we are in. int i1, j1, k1; // Offsets for second corner of simplex in (i,j,k) coords int i2, j2, k2; // Offsets for third corner of simplex in (i,j,k) coords /* This code would benefit from a backport from the GLSL version! */ if (x0 >= y0) { if (y0 >= z0) { i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 1; k2 = 0; } // X Y Z order else if (x0 >= z0) { i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 0; k2 = 1; } // X Z Y order else { i1 = 0; j1 = 0; k1 = 1; i2 = 1; j2 = 0; k2 = 1; } // Z X Y order } else { // x0<y0 if (y0 < z0) { i1 = 0; j1 = 0; k1 = 1; i2 = 0; j2 = 1; k2 = 1; } // Z Y X order else if (x0 < z0) { i1 = 0; j1 = 1; k1 = 0; i2 = 0; j2 = 1; k2 = 1; } // Y Z X order else { i1 = 0; j1 = 1; k1 = 0; i2 = 1; j2 = 1; k2 = 0; } // Y X Z order } // A step of (1,0,0) in (i,j,k) means a step of (1-c,-c,-c) in (x,y,z), // a step of (0,1,0) in (i,j,k) means a step of (-c,1-c,-c) in (x,y,z), and // a step of (0,0,1) in (i,j,k) means a step of (-c,-c,1-c) in (x,y,z), where // c = 1/6. float x1 = x0 - i1 + G3; // Offsets for second corner in (x,y,z) coords float y1 = y0 - j1 + G3; float z1 = z0 - k1 + G3; float x2 = x0 - i2 + 2.0f * G3; // Offsets for third corner in (x,y,z) coords float y2 = y0 - j2 + 2.0f * G3; float z2 = z0 - k2 + 2.0f * G3; float x3 = x0 - 1.0f + 3.0f * G3; // Offsets for last corner in (x,y,z) coords float y3 = y0 - 1.0f + 3.0f * G3; float z3 = z0 - 1.0f + 3.0f * G3; // Wrap the integer indices at 256, to avoid indexing perm[] out of bounds int ii = i % 256; int jj = j % 256; int kk = k % 256; // Calculate the contribution from the four corners float t0 = 0.6f - x0 * x0 - y0 * y0 - z0 * z0; if (t0 < 0.0f) n0 = 0.0f; else { t0 *= t0; n0 = t0 * t0 * grad(perm[ii + perm[jj + perm[kk]]], x0, y0, z0); } float t1 = 0.6f - x1 * x1 - y1 * y1 - z1 * z1; if (t1 < 0.0f) n1 = 0.0f; else { t1 *= t1; n1 = t1 * t1 * grad(perm[ii + i1 + perm[jj + j1 + perm[kk + k1]]], x1, y1, z1); } float t2 = 0.6f - x2 * x2 - y2 * y2 - z2 * z2; if (t2 < 0.0f) n2 = 0.0f; else { t2 *= t2; n2 = t2 * t2 * grad(perm[ii + i2 + perm[jj + j2 + perm[kk + k2]]], x2, y2, z2); } float t3 = 0.6f - x3 * x3 - y3 * y3 - z3 * z3; if (t3 < 0.0f) n3 = 0.0f; else { t3 *= t3; n3 = t3 * t3 * grad(perm[ii + 1 + perm[jj + 1 + perm[kk + 1]]], x3, y3, z3); } // Add contributions from each corner to get the final noise value. // The result is scaled to stay just inside [-1,1] return 32.0f * (n0 + n1 + n2 + n3); // TODO: The scale factor is preliminary! } private static byte[] perm = new byte[512] { 151,160,137,91,90,15, 131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23, 190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33, 88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166, 77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244, 102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196, 135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123, 5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42, 223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9, 129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228, 251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107, 49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254, 138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180, 151,160,137,91,90,15, 131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23, 190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33, 88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166, 77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244, 102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196, 135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123, 5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42, 223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9, 129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228, 251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107, 49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254, 138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180 }; private static int FastFloor(float x) { return (x > 0) ? ((int)x) : (((int)x) - 1); } private static float grad(int hash, float x) { int h = hash & 15; float grad = 1.0f + (h & 7); // Gradient value 1.0, 2.0, ..., 8.0 if ((h & 8) != 0) grad = -grad; // Set a random sign for the gradient return (grad * x); // Multiply the gradient with the distance } private static float grad(int hash, float x, float y) { int h = hash & 7; // Convert low 3 bits of hash code float u = h < 4 ? x : y; // into 8 simple gradient directions, float v = h < 4 ? y : x; // and compute the dot product with (x,y). return ((h & 1) != 0 ? -u : u) + ((h & 2) != 0 ? -2.0f * v : 2.0f * v); } private static float grad(int hash, float x, float y, float z) { int h = hash & 15; // Convert low 4 bits of hash code into 12 simple float u = h < 8 ? x : y; // gradient directions, and compute dot product. float v = h < 4 ? y : h == 12 || h == 14 ? x : z; // Fix repeats at h = 12 to 15 return ((h & 1) != 0 ? -u : u) + ((h & 2) != 0 ? -v : v); } private static float grad(int hash, float x, float y, float z, float t) { int h = hash & 31; // Convert low 5 bits of hash code into 32 simple float u = h < 24 ? x : y; // gradient directions, and compute dot product. float v = h < 16 ? y : z; float w = h < 8 ? z : t; return ((h & 1) != 0 ? -u : u) + ((h & 2) != 0 ? -v : v) + ((h & 4) != 0 ? -w : w); } This Is My World Generation Code Block[,] BlocksInMap = new Block[1024, 256]; public bool IsWorldGenerated = false; Random r = new Random(); private void RunThread() { for (int BH = 0; BH <= 256; BH++) { for (int BW = 0; BW <= 1024; BW++) { Block b = new Block(); if (BH >= 192) { } BlocksInMap[BW, BH] = b; } } IsWorldGenerated = true; } public void GenWorld() { new Thread(new ThreadStart(RunThread)).Start(); } And This Is A Example Of How I Set Blocks Block b = new Block(); b.BlockType = = Block.BlockTypes.Air; This Is A Example Of How I Set Models foreach (Block b in MyWorld) { switch(b.BlockType) { case Block.BlockTypes.Dirt: b.Model = DirtModel; break; ect. } } How Would I Use These To Generate To World (The Block Array) And If Possible Thread It More? btw It's 1024 Wide And 256 Tall

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  • Plan Caching and Query Memory Part II (Hash Match) – When not to use stored procedure - Most common performance mistake SQL Server developers make.

    - by sqlworkshops
    SQL Server estimates Memory requirement at compile time, when stored procedure or other plan caching mechanisms like sp_executesql or prepared statement are used, the memory requirement is estimated based on first set of execution parameters. This is a common reason for spill over tempdb and hence poor performance. Common memory allocating queries are that perform Sort and do Hash Match operations like Hash Join or Hash Aggregation or Hash Union. This article covers Hash Match operations with examples. It is recommended to read Plan Caching and Query Memory Part I before this article which covers an introduction and Query memory for Sort. In most cases it is cheaper to pay for the compilation cost of dynamic queries than huge cost for spill over tempdb, unless memory requirement for a query does not change significantly based on predicates.   This article covers underestimation / overestimation of memory for Hash Match operation. Plan Caching and Query Memory Part I covers underestimation / overestimation for Sort. It is important to note that underestimation of memory for Sort and Hash Match operations lead to spill over tempdb and hence negatively impact performance. Overestimation of memory affects the memory needs of other concurrently executing queries. In addition, it is important to note, with Hash Match operations, overestimation of memory can actually lead to poor performance.   To read additional articles I wrote click here.   The best way to learn is to practice. To create the below tables and reproduce the behavior, join the mailing list by using this link: www.sqlworkshops.com/ml and I will send you the table creation script. Most of these concepts are also covered in our webcasts: www.sqlworkshops.com/webcasts  Let’s create a Customer’s State table that has 99% of customers in NY and the rest 1% in WA.Customers table used in Part I of this article is also used here.To observe Hash Warning, enable 'Hash Warning' in SQL Profiler under Events 'Errors and Warnings'. --Example provided by www.sqlworkshops.com drop table CustomersState go create table CustomersState (CustomerID int primary key, Address char(200), State char(2)) go insert into CustomersState (CustomerID, Address) select CustomerID, 'Address' from Customers update CustomersState set State = 'NY' where CustomerID % 100 != 1 update CustomersState set State = 'WA' where CustomerID % 100 = 1 go update statistics CustomersState with fullscan go   Let’s create a stored procedure that joins customers with CustomersState table with a predicate on State. --Example provided by www.sqlworkshops.com create proc CustomersByState @State char(2) as begin declare @CustomerID int select @CustomerID = e.CustomerID from Customers e inner join CustomersState es on (e.CustomerID = es.CustomerID) where es.State = @State option (maxdop 1) end go  Let’s execute the stored procedure first with parameter value ‘WA’ – which will select 1% of data. set statistics time on go --Example provided by www.sqlworkshops.com exec CustomersByState 'WA' goThe stored procedure took 294 ms to complete.  The stored procedure was granted 6704 KB based on 8000 rows being estimated.  The estimated number of rows, 8000 is similar to actual number of rows 8000 and hence the memory estimation should be ok.  There was no Hash Warning in SQL Profiler. To observe Hash Warning, enable 'Hash Warning' in SQL Profiler under Events 'Errors and Warnings'.   Now let’s execute the stored procedure with parameter value ‘NY’ – which will select 99% of data. -Example provided by www.sqlworkshops.com exec CustomersByState 'NY' go  The stored procedure took 2922 ms to complete.   The stored procedure was granted 6704 KB based on 8000 rows being estimated.    The estimated number of rows, 8000 is way different from the actual number of rows 792000 because the estimation is based on the first set of parameter value supplied to the stored procedure which is ‘WA’ in our case. This underestimation will lead to spill over tempdb, resulting in poor performance.   There was Hash Warning (Recursion) in SQL Profiler. To observe Hash Warning, enable 'Hash Warning' in SQL Profiler under Events 'Errors and Warnings'.   Let’s recompile the stored procedure and then let’s first execute the stored procedure with parameter value ‘NY’.  In a production instance it is not advisable to use sp_recompile instead one should use DBCC FREEPROCCACHE (plan_handle). This is due to locking issues involved with sp_recompile, refer to our webcasts, www.sqlworkshops.com/webcasts for further details.   exec sp_recompile CustomersByState go --Example provided by www.sqlworkshops.com exec CustomersByState 'NY' go  Now the stored procedure took only 1046 ms instead of 2922 ms.   The stored procedure was granted 146752 KB of memory. The estimated number of rows, 792000 is similar to actual number of rows of 792000. Better performance of this stored procedure execution is due to better estimation of memory and avoiding spill over tempdb.   There was no Hash Warning in SQL Profiler.   Now let’s execute the stored procedure with parameter value ‘WA’. --Example provided by www.sqlworkshops.com exec CustomersByState 'WA' go  The stored procedure took 351 ms to complete, higher than the previous execution time of 294 ms.    This stored procedure was granted more memory (146752 KB) than necessary (6704 KB) based on parameter value ‘NY’ for estimation (792000 rows) instead of parameter value ‘WA’ for estimation (8000 rows). This is because the estimation is based on the first set of parameter value supplied to the stored procedure which is ‘NY’ in this case. This overestimation leads to poor performance of this Hash Match operation, it might also affect the performance of other concurrently executing queries requiring memory and hence overestimation is not recommended.     The estimated number of rows, 792000 is much more than the actual number of rows of 8000.  Intermediate Summary: This issue can be avoided by not caching the plan for memory allocating queries. Other possibility is to use recompile hint or optimize for hint to allocate memory for predefined data range.Let’s recreate the stored procedure with recompile hint. --Example provided by www.sqlworkshops.com drop proc CustomersByState go create proc CustomersByState @State char(2) as begin declare @CustomerID int select @CustomerID = e.CustomerID from Customers e inner join CustomersState es on (e.CustomerID = es.CustomerID) where es.State = @State option (maxdop 1, recompile) end go  Let’s execute the stored procedure initially with parameter value ‘WA’ and then with parameter value ‘NY’. --Example provided by www.sqlworkshops.com exec CustomersByState 'WA' go exec CustomersByState 'NY' go  The stored procedure took 297 ms and 1102 ms in line with previous optimal execution times.   The stored procedure with parameter value ‘WA’ has good estimation like before.   Estimated number of rows of 8000 is similar to actual number of rows of 8000.   The stored procedure with parameter value ‘NY’ also has good estimation and memory grant like before because the stored procedure was recompiled with current set of parameter values.  Estimated number of rows of 792000 is similar to actual number of rows of 792000.    The compilation time and compilation CPU of 1 ms is not expensive in this case compared to the performance benefit.   There was no Hash Warning in SQL Profiler.   Let’s recreate the stored procedure with optimize for hint of ‘NY’. --Example provided by www.sqlworkshops.com drop proc CustomersByState go create proc CustomersByState @State char(2) as begin declare @CustomerID int select @CustomerID = e.CustomerID from Customers e inner join CustomersState es on (e.CustomerID = es.CustomerID) where es.State = @State option (maxdop 1, optimize for (@State = 'NY')) end go  Let’s execute the stored procedure initially with parameter value ‘WA’ and then with parameter value ‘NY’. --Example provided by www.sqlworkshops.com exec CustomersByState 'WA' go exec CustomersByState 'NY' go  The stored procedure took 353 ms with parameter value ‘WA’, this is much slower than the optimal execution time of 294 ms we observed previously. This is because of overestimation of memory. The stored procedure with parameter value ‘NY’ has optimal execution time like before.   The stored procedure with parameter value ‘WA’ has overestimation of rows because of optimize for hint value of ‘NY’.   Unlike before, more memory was estimated to this stored procedure based on optimize for hint value ‘NY’.    The stored procedure with parameter value ‘NY’ has good estimation because of optimize for hint value of ‘NY’. Estimated number of rows of 792000 is similar to actual number of rows of 792000.   Optimal amount memory was estimated to this stored procedure based on optimize for hint value ‘NY’.   There was no Hash Warning in SQL Profiler.   This article covers underestimation / overestimation of memory for Hash Match operation. Plan Caching and Query Memory Part I covers underestimation / overestimation for Sort. It is important to note that underestimation of memory for Sort and Hash Match operations lead to spill over tempdb and hence negatively impact performance. Overestimation of memory affects the memory needs of other concurrently executing queries. In addition, it is important to note, with Hash Match operations, overestimation of memory can actually lead to poor performance.   Summary: Cached plan might lead to underestimation or overestimation of memory because the memory is estimated based on first set of execution parameters. It is recommended not to cache the plan if the amount of memory required to execute the stored procedure has a wide range of possibilities. One can mitigate this by using recompile hint, but that will lead to compilation overhead. However, in most cases it might be ok to pay for compilation rather than spilling sort over tempdb which could be very expensive compared to compilation cost. The other possibility is to use optimize for hint, but in case one sorts more data than hinted by optimize for hint, this will still lead to spill. On the other side there is also the possibility of overestimation leading to unnecessary memory issues for other concurrently executing queries. In case of Hash Match operations, this overestimation of memory might lead to poor performance. When the values used in optimize for hint are archived from the database, the estimation will be wrong leading to worst performance, so one has to exercise caution before using optimize for hint, recompile hint is better in this case.   I explain these concepts with detailed examples in my webcasts (www.sqlworkshops.com/webcasts), I recommend you to watch them. The best way to learn is to practice. To create the above tables and reproduce the behavior, join the mailing list at www.sqlworkshops.com/ml and I will send you the relevant SQL Scripts.  Register for the upcoming 3 Day Level 400 Microsoft SQL Server 2008 and SQL Server 2005 Performance Monitoring & Tuning Hands-on Workshop in London, United Kingdom during March 15-17, 2011, click here to register / Microsoft UK TechNet.These are hands-on workshops with a maximum of 12 participants and not lectures. For consulting engagements click here.   Disclaimer and copyright information:This article refers to organizations and products that may be the trademarks or registered trademarks of their various owners. Copyright of this article belongs to R Meyyappan / www.sqlworkshops.com. You may freely use the ideas and concepts discussed in this article with acknowledgement (www.sqlworkshops.com), but you may not claim any of it as your own work. This article is for informational purposes only; you use any of the suggestions given here entirely at your own risk.   R Meyyappan [email protected] LinkedIn: http://at.linkedin.com/in/rmeyyappan

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  • Basics of Join Factorization

    - by Hong Su
    We continue our series on optimizer transformations with a post that describes the Join Factorization transformation. The Join Factorization transformation was introduced in Oracle 11g Release 2 and applies to UNION ALL queries. Union all queries are commonly used in database applications, especially in data integration applications. In many scenarios the branches in a UNION All query share a common processing, i.e, refer to the same tables. In the current Oracle execution strategy, each branch of a UNION ALL query is evaluated independently, which leads to repetitive processing, including data access and join. The join factorization transformation offers an opportunity to share the common computations across the UNION ALL branches. Currently, join factorization only factorizes common references to base tables only, i.e, not views. Consider a simple example of query Q1. Q1:    select t1.c1, t2.c2    from t1, t2, t3    where t1.c1 = t2.c1 and t1.c1 > 1 and t2.c2 = 2 and t2.c2 = t3.c2   union all    select t1.c1, t2.c2    from t1, t2, t4    where t1.c1 = t2.c1 and t1.c1 > 1 and t2.c3 = t4.c3; Table t1 appears in both the branches. As does the filter predicates on t1 (t1.c1 > 1) and the join predicates involving t1 (t1.c1 = t2.c1). Nevertheless, without any transformation, the scan (and the filtering) on t1 has to be done twice, once per branch. Such a query may benefit from join factorization which can transform Q1 into Q2 as follows: Q2:    select t1.c1, VW_JF_1.item_2    from t1, (select t2.c1 item_1, t2.c2 item_2                   from t2, t3                    where t2.c2 = t3.c2 and t2.c2 = 2                                  union all                   select t2.c1 item_1, t2.c2 item_2                   from t2, t4                    where t2.c3 = t4.c3) VW_JF_1    where t1.c1 = VW_JF_1.item_1 and t1.c1 > 1; In Q2, t1 is "factorized" and thus the table scan and the filtering on t1 is done only once (it's shared). If t1 is large, then avoiding one extra scan of t1 can lead to a huge performance improvement. Another benefit of join factorization is that it can open up more join orders. Let's look at query Q3. Q3:    select *    from t5, (select t1.c1, t2.c2                  from t1, t2, t3                  where t1.c1 = t2.c1 and t1.c1 > 1 and t2.c2 = 2 and t2.c2 = t3.c2                 union all                  select t1.c1, t2.c2                  from t1, t2, t4                  where t1.c1 = t2.c1 and t1.c1 > 1 and t2.c3 = t4.c3) V;   where t5.c1 = V.c1 In Q3, view V is same as Q1. Before join factorization, t1, t2 and t3 must be joined first before they can be joined with t5. But if join factorization factorizes t1 from view V, t1 can then be joined with t5. This opens up new join orders. That being said, join factorization imposes certain join orders. For example, in Q2, t2 and t3 appear in the first branch of the UNION ALL query in view VW_JF_1. T2 must be joined with t3 before it can be joined with t1 which is outside of the VW_JF_1 view. The imposed join order may not necessarily be the best join order. For this reason, join factorization is performed under cost-based transformation framework; this means that we cost the plans with and without join factorization and choose the cheapest plan. Note that if the branches in UNION ALL have DISTINCT clauses, join factorization is not valid. For example, Q4 is NOT semantically equivalent to Q5.   Q4:     select distinct t1.*      from t1, t2      where t1.c1 = t2.c1  union all      select distinct t1.*      from t1, t2      where t1.c1 = t2.c1 Q5:    select distinct t1.*     from t1, (select t2.c1 item_1                   from t2                union all                   select t2.c1 item_1                  from t2) VW_JF_1     where t1.c1 = VW_JF_1.item_1 Q4 might return more rows than Q5. Q5's results are guaranteed to be duplicate free because of the DISTINCT key word at the top level while Q4's results might contain duplicates.   The examples given so far involve inner joins only. Join factorization is also supported in outer join, anti join and semi join. But only the right tables of outer join, anti join and semi joins can be factorized. It is not semantically correct to factorize the left table of outer join, anti join or semi join. For example, Q6 is NOT semantically equivalent to Q7. Q6:     select t1.c1, t2.c2    from t1, t2    where t1.c1 = t2.c1(+) and t2.c2 (+) = 2  union all    select t1.c1, t2.c2    from t1, t2      where t1.c1 = t2.c1(+) and t2.c2 (+) = 3 Q7:     select t1.c1, VW_JF_1.item_2    from t1, (select t2.c1 item_1, t2.c2 item_2                  from t2                  where t2.c2 = 2                union all                  select t2.c1 item_1, t2.c2 item_2                  from t2                                                                                                    where t2.c2 = 3) VW_JF_1       where t1.c1 = VW_JF_1.item_1(+)                                                                  However, the right side of an outer join can be factorized. For example, join factorization can transform Q8 to Q9 by factorizing t2, which is the right table of an outer join. Q8:    select t1.c2, t2.c2    from t1, t2      where t1.c1 = t2.c1 (+) and t1.c1 = 1 union all    select t1.c2, t2.c2    from t1, t2    where t1.c1 = t2.c1(+) and t1.c1 = 2 Q9:   select VW_JF_1.item_2, t2.c2   from t2,             (select t1.c1 item_1, t1.c2 item_2            from t1            where t1.c1 = 1           union all            select t1.c1 item_1, t1.c2 item_2            from t1            where t1.c1 = 2) VW_JF_1   where VW_JF_1.item_1 = t2.c1(+) All of the examples in this blog show factorizing a single table from two branches. This is just for ease of illustration. Join factorization can factorize multiple tables and from more than two UNION ALL branches.  SummaryJoin factorization is a cost-based transformation. It can factorize common computations from branches in a UNION ALL query which can lead to huge performance improvement. 

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  • Securing an ADF Application using OES11g: Part 2

    - by user12587121
    To validate the integration with OES we need a sample ADF Application that is rich enough to allow us to test securing the various ADF elements.  To achieve this we can add some items including bounded task flows to the application developed in this tutorial. A sample JDeveloper 11.1.1.6 project is available here. It depends on the Fusion Order Demo (FOD) database schema which is easily created using the FOD build scripts.In the deployment we have chosen to enable only ADF Authentication as we will delegate Authorization, mostly, to OES.The welcome page of the application with all the links exposed looks as follows: The Welcome, Browse Products, Browse Stock and System Administration links go to pages while the Supplier Registration and Update Stock are bounded task flows.  The Login link goes to a basic login page and once logged in a link is presented that goes to a logout page.  Only the Browse Products and Browse Stock pages are really connected to the database--the other pages and task flows do not really perform any operations on the database. Required Security Policies We make use of a set of test users and roles as decscribed on the welcome page of the application.  In order to exercise the different authorization possibilities we would like to enforce the following sample policies: Anonymous users can see the Login, Welcome and Supplier Registration links. They can also see the Welcome page, the Login page and follow the Supplier Registration task flow.  They can see the icon adjacent to the Login link indicating whether they have logged in or not. Authenticated users can see the Browse Product page. Only staff granted the right can see the Browse Product page cost price value returned from the database and then only if the value is below a configurable limit. Suppliers and staff can see the Browse Stock links and pages.  Customers cannot. Suppliers can see the Update Stock link but only those with the update permission are allowed to follow the task flow that it launches.  We could hide the link but leave it exposed here so we can easily demonstrate the method call activity protecting the task flow. Only staff granted the right can see the System Administration link and the System Administration page it accesses. Implementing the required policies In order to secure the application we will make use of the following techniques: EL Expressions and Java backing beans: JSF has the notion of EL expressions to reference data from backing Java classes.  We use these to control the presentation of links on the navigation page which respect the security contraints.  So a user will not see links that he is not allowed to click on into. These Java backing beans can call on to OES for an authorization decision.  Important Note: naturally we would configure the WLS domain where our ADF application is running as an OES WLS SM, which would allow us to efficiently query OES over the PEP API.  However versioning conflicts between OES 11.1.1.5 and ADF 11.1.1.6 mean that this is not possible.  Nevertheless, we can make use of the OES RESTful gateway technique from this posting in order to call into OES. You can easily create and manage backing beans in Jdeveloper as follows: Custom ADF Phase Listener: ADF extends the JSF page lifecycle flow and allows one to hook into the flow to intercept page rendering.  We use this to put a check prior to rendering any protected pages, again calling on to OES via the backing bean.  Phase listeners are configured in the adf-settings.xml file.  See the MyPageListener.java class in the project.  Here, for example,  is the code we use in the listener to check for allowed access to the sysadmin page, navigating back to the welcome page if authorization is not granted:                         if (page != null && (page.equals("/system.jspx") || page.equals("/system"))){                             System.out.println("MyPageListener: Checking Authorization for /system");                             if (getValue("#{oesBackingBean.UIAccessSysAdmin}").toString().equals("false") ){                                   System.out.println("MyPageListener: Forcing navigation away from system" +                                       "to welcome");                                 NavigationHandler nh = fc.getApplication().getNavigationHandler();                                   nh.handleNavigation(fc, null, "welcome");                               } else {                                 System.out.println("MyPageListener: access allowed");                              }                         } Method call activity: our app makes use of bounded task flows to implement the sequence of pages that update the stock or allow suppliers to self register.  ADF takes care of ensuring that a bounded task flow can be entered by only one page.  So a way to protect all those pages is to make a call to OES in the first activity and then either exit the task flow or continue depending on the authorization decision.  The method call returns a String which contains the name of the transition to effect. This is where we configure the method call activity in JDeveloper: We implement each of the policies using the above techniques as follows: Policies 1 and 2: as these policies concern the coarse grained notions of controlling access to anonymous and authenticated users we can make use of the container’s security constraints which can be defined in the web.xml file.  The allPages constraint is added automatically when we configure Authentication for the ADF application.  We have added the “anonymousss” constraint to allow access to the the required pages, task flows and icons: <security-constraint>    <web-resource-collection>      <web-resource-name>anonymousss</web-resource-name>      <url-pattern>/faces/welcome</url-pattern>      <url-pattern>/afr/*</url-pattern>      <url-pattern>/adf/*</url-pattern>      <url-pattern>/key.png</url-pattern>      <url-pattern>/faces/supplier-reg-btf/*</url-pattern>      <url-pattern>/faces/supplier_register_complete</url-pattern>    </web-resource-collection>  </security-constraint> Policy 3: we can place an EL expression on the element representing the cost price on the products.jspx page: #{oesBackingBean.dataAccessCostPrice}. This EL Expression references a method in a Java backing bean that will call on to OES for an authorization decision.  In OES we model the authorization requirement by requiring the view permission on the resource /MyADFApp/data/costprice and granting it only to the staff application role.  We recover any obligations to determine the limit.  Policy 4: is implemented by putting an EL expression on the Browse Stock link #{oesBackingBean.UIAccessBrowseStock} which checks for the view permission on the /MyADFApp/ui/stock resource. The stock.jspx page is protected by checking for the same permission in a custom phase listener—if the required permission is not satisfied then we force navigation back to the welcome page. Policy 5: the Update Stock link is protected with the same EL expression as the Browse Link: #{oesBackingBean.UIAccessBrowseStock}.  However the Update Stock link launches a bounded task flow and to protect it the first activity in the flow is a method call activity which will execute an EL expression #{oesBackingBean.isUIAccessSupplierUpdateTransition}  to check for the update permission on the /MyADFApp/ui/stock resource and either transition to the next step in the flow or terminate the flow with an authorization error. Policy 6: the System Administration link is protected with an EL Expression #{oesBackingBean.UIAccessSysAdmin} that checks for view access on the /MyADF/ui/sysadmin resource.  The system page is protected in the same way at the stock page—the custom phase listener checks for the same permission that protects the link and if not satisfied we navigate back to the welcome page. Testing the Application To test the application: deploy the OES11g Admin to a WLS domain deploy the OES gateway in a another domain configured to be a WLS SM. You must ensure that the jps-config.xml file therein is configured to allow access to the identity store, otherwise the gateway will not b eable to resolve the principals for the requested users.  To do this ensure that the following elements appear in the jps-config.xml file: <serviceProvider type="IDENTITY_STORE" name="idstore.ldap.provider" class="oracle.security.jps.internal.idstore.ldap.LdapIdentityStoreProvider">             <description>LDAP-based IdentityStore Provider</description>  </serviceProvider> <serviceInstance name="idstore.ldap" provider="idstore.ldap.provider">             <property name="idstore.config.provider" value="oracle.security.jps.wls.internal.idstore.WlsLdapIdStoreConfigProvider"/>             <property name="CONNECTION_POOL_CLASS" value="oracle.security.idm.providers.stdldap.JNDIPool"/></serviceInstance> <serviceInstanceRef ref="idstore.ldap"/> download the sample application and change the URL to the gateway in the MyADFApp OESBackingBean code to point to the OES Gateway and deploy the application to an 11.1.1.6 WLS domain that has been extended with the ADF JRF files. You will need to configure the FOD database connection to point your database which contains the FOD schema. populate the OES Admin and OES Gateway WLS LDAP stores with the sample set of users and groups.  If  you have configured the WLS domains to point to the same LDAP then it would only have to be done once.  To help with this there is a directory called ldap_scripts in the sample project with ldif files for the test users and groups. start the OES Admin console and configure the required OES authorization policies for the MyADFApp application and push them to the WLS SM containing the OES Gateway. Login to the MyADFApp as each of the users described on the login page to test that the security policy is correct. You will see informative logging from the OES Gateway and the ADF application to their respective WLS consoles. Congratulations, you may now login to the OES Admin console and change policies that will control the behaviour of your ADF application--change the limit value in the obligation for the cost price for example, or define Role Mapping policies to determine staff access to the system administration page based on user profile attributes. ADF Development Notes Some notes on ADF development which are probably typical gotchas: May need this on WLS startup in order to allow us to overwrite credentials for the database, the signal here is that there is an error trying to access the data base: -Djps.app.credential.overwrite.allowed=true Best to call Bounded Task flows via a CommandLink (as opposed to a go link) as you cannot seem to start them again from a go link, even having completed the task flow correctly with a return activity. Once a bounded task flow (BTF) is initated it must complete correctly  via a return activity—attempting to click on any other link whilst in the context of a  BTF has no effect.  See here for example: When using the ADF Authentication only security approach it seems to be awkward to allow anonymous access to the welcome and registration pages.  We can achieve anonymous access using the web.xml security constraint shown above (where no auth-constraint is specified) however it is not clear what needs to be listed in there….for example the /afr/* and /adf/* are in there by trial and error as sometimes the welcome page will not render if we omit those items.  I was not able to use the default allPages constraint with for example the anonymous-role or the everyone WLS group in order to be able to allow anonymous access to pages. The ADF security best practice advises placing all pages under the public_html/WEB-INF folder as then ADF will not allow any direct access to the .jspx pages but will only allow acces via a link of the form /faces/welcome rather than /faces/welcome.jspx.  This seems like a very good practice to follow as having multiple entry points to data is a source of confusion in a web application (particulary from a security point of view). In Authentication+Authorization mode only pages with a Page definition file are protected.  In order to add an emty one right click on the page and choose Go to Page Definition.  This will create an empty page definition and now the page will require explicit permission to be seen. It is advisable to give a unique context root via the weblogic.xml for the application, as otherwise the application will clash with any other application with the same context root and it will not deploy

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  • 12c - flashforward, flashback or see it as of now...

    - by noreply(at)blogger.com (Thomas Kyte)
    Oracle 9i exposed flashback query to developers for the first time.  The ability to flashback query dates back to version 4 however (it just wasn't exposed).  Every time you run a query in Oracle it is in fact a flashback query - it is what multi-versioning is all about.However, there was never a flashforward query (well, ok, the workspace manager has this capability - but with lots of extra baggage).  We've never been able to ask a table "what will you look like tomorrow" - but now we do.The capability is called Temporal Validity.  If you have a table with data that is effective dated - has a "start date" and "end date" column in it - we can now query it using flashback query like syntax.  The twist is - the date we "flashback" to can be in the future.  It works by rewriting the query to transparently the necessary where clause and filter out the right rows for the right period of time - and since you can have records whose start date is in the future - you can query a table and see what it would look like at some future time.Here is a quick example, we'll start with a table:ops$tkyte%ORA12CR1> create table addresses  2  ( empno       number,  3    addr_data   varchar2(30),  4    start_date  date,  5    end_date    date,  6    period for valid(start_date,end_date)  7  )  8  /Table created.the new bit is on line 6 (it can be altered into an existing table - so any table  you have with a start/end date column will be a candidate).  The keyword is PERIOD, valid is an identifier I chose - it could have been foobar, valid just sounds nice in the query later.  You identify the columns in your table - or we can create them for you if they don't exist.  Then you just create some data:ops$tkyte%ORA12CR1> insert into addresses (empno, addr_data, start_date, end_date )  2  values ( 1234, '123 Main Street', trunc(sysdate-5), trunc(sysdate-2) );1 row created.ops$tkyte%ORA12CR1>ops$tkyte%ORA12CR1> insert into addresses (empno, addr_data, start_date, end_date )  2  values ( 1234, '456 Fleet Street', trunc(sysdate-1), trunc(sysdate+1) );1 row created.ops$tkyte%ORA12CR1>ops$tkyte%ORA12CR1> insert into addresses (empno, addr_data, start_date, end_date )  2  values ( 1234, '789 1st Ave', trunc(sysdate+2), null );1 row created.and you can either see all of the data:ops$tkyte%ORA12CR1> select * from addresses;     EMPNO ADDR_DATA                      START_DAT END_DATE---------- ------------------------------ --------- ---------      1234 123 Main Street                27-JUN-13 30-JUN-13      1234 456 Fleet Street               01-JUL-13 03-JUL-13      1234 789 1st Ave                    04-JUL-13or query "as of" some point in time - as  you can see in the predicate section - it is just doing a query rewrite to automate the "where" filters:ops$tkyte%ORA12CR1> select * from addresses as of period for valid sysdate-3;     EMPNO ADDR_DATA                      START_DAT END_DATE---------- ------------------------------ --------- ---------      1234 123 Main Street                27-JUN-13 30-JUN-13ops$tkyte%ORA12CR1> @planops$tkyte%ORA12CR1> select * from table(dbms_xplan.display_cursor);PLAN_TABLE_OUTPUT-------------------------------------------------------------------------------SQL_ID  cthtvvm0dxvva, child number 0-------------------------------------select * from addresses as of period for valid sysdate-3Plan hash value: 3184888728-------------------------------------------------------------------------------| Id  | Operation         | Name      | Rows  | Bytes | Cost (%CPU)| Time     |-------------------------------------------------------------------------------|   0 | SELECT STATEMENT  |           |       |       |     3 (100)|          ||*  1 |  TABLE ACCESS FULL| ADDRESSES |     1 |    48 |     3   (0)| 00:00:01 |-------------------------------------------------------------------------------Predicate Information (identified by operation id):---------------------------------------------------   1 - filter((("T"."START_DATE" IS NULL OR              "T"."START_DATE"<=SYSDATE@!-3) AND ("T"."END_DATE" IS NULL OR              "T"."END_DATE">SYSDATE@!-3)))Note-----   - dynamic statistics used: dynamic sampling (level=2)24 rows selected.ops$tkyte%ORA12CR1> select * from addresses as of period for valid sysdate;     EMPNO ADDR_DATA                      START_DAT END_DATE---------- ------------------------------ --------- ---------      1234 456 Fleet Street               01-JUL-13 03-JUL-13ops$tkyte%ORA12CR1> @planops$tkyte%ORA12CR1> select * from table(dbms_xplan.display_cursor);PLAN_TABLE_OUTPUT-------------------------------------------------------------------------------SQL_ID  26ubyhw9hgk7z, child number 0-------------------------------------select * from addresses as of period for valid sysdatePlan hash value: 3184888728-------------------------------------------------------------------------------| Id  | Operation         | Name      | Rows  | Bytes | Cost (%CPU)| Time     |-------------------------------------------------------------------------------|   0 | SELECT STATEMENT  |           |       |       |     3 (100)|          ||*  1 |  TABLE ACCESS FULL| ADDRESSES |     1 |    48 |     3   (0)| 00:00:01 |-------------------------------------------------------------------------------Predicate Information (identified by operation id):---------------------------------------------------   1 - filter((("T"."START_DATE" IS NULL OR              "T"."START_DATE"<=SYSDATE@!) AND ("T"."END_DATE" IS NULL OR              "T"."END_DATE">SYSDATE@!)))Note-----   - dynamic statistics used: dynamic sampling (level=2)24 rows selected.ops$tkyte%ORA12CR1> select * from addresses as of period for valid sysdate+3;     EMPNO ADDR_DATA                      START_DAT END_DATE---------- ------------------------------ --------- ---------      1234 789 1st Ave                    04-JUL-13ops$tkyte%ORA12CR1> @planops$tkyte%ORA12CR1> select * from table(dbms_xplan.display_cursor);PLAN_TABLE_OUTPUT-------------------------------------------------------------------------------SQL_ID  36bq7shnhc888, child number 0-------------------------------------select * from addresses as of period for valid sysdate+3Plan hash value: 3184888728-------------------------------------------------------------------------------| Id  | Operation         | Name      | Rows  | Bytes | Cost (%CPU)| Time     |-------------------------------------------------------------------------------|   0 | SELECT STATEMENT  |           |       |       |     3 (100)|          ||*  1 |  TABLE ACCESS FULL| ADDRESSES |     1 |    48 |     3   (0)| 00:00:01 |-------------------------------------------------------------------------------Predicate Information (identified by operation id):---------------------------------------------------   1 - filter((("T"."START_DATE" IS NULL OR              "T"."START_DATE"<=SYSDATE@!+3) AND ("T"."END_DATE" IS NULL OR              "T"."END_DATE">SYSDATE@!+3)))Note-----   - dynamic statistics used: dynamic sampling (level=2)24 rows selected.All in all a nice, easy way to query effective dated information as of a point in time without a complex where clause.  You need to maintain the data - it isn't that a delete will turn into an update the end dates a record or anything - but if you have tables with start/end dates, this will make it much easier to query them.

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  • Selling Federal Enterprise Architecture (EA)

    - by TedMcLaughlan
    Selling Federal Enterprise Architecture A taxonomy of subject areas, from which to develop a prioritized marketing and communications plan to evangelize EA activities within and among US Federal Government organizations and constituents. Any and all feedback is appreciated, particularly in developing and extending this discussion as a tool for use – more information and details are also available. "Selling" the discipline of Enterprise Architecture (EA) in the Federal Government (particularly in non-DoD agencies) is difficult, notwithstanding the general availability and use of the Federal Enterprise Architecture Framework (FEAF) for some time now, and the relatively mature use of the reference models in the OMB Capital Planning and Investment (CPIC) cycles. EA in the Federal Government also tends to be a very esoteric and hard to decipher conversation – early apologies to those who agree to continue reading this somewhat lengthy article. Alignment to the FEAF and OMB compliance mandates is long underway across the Federal Departments and Agencies (and visible via tools like PortfolioStat and ITDashboard.gov – but there is still a gap between the top-down compliance directives and enablement programs, and the bottom-up awareness and effective use of EA for either IT investment management or actual mission effectiveness. "EA isn't getting deep enough penetration into programs, components, sub-agencies, etc.", verified a panelist at the most recent EA Government Conference in DC. Newer guidance from OMB may be especially difficult to handle, where bottom-up input can't be accurately aligned, analyzed and reported via standardized EA discipline at the Agency level – for example in addressing the new (for FY13) Exhibit 53D "Agency IT Reductions and Reinvestments" and the information required for "Cloud Computing Alternatives Evaluation" (supporting the new Exhibit 53C, "Agency Cloud Computing Portfolio"). Therefore, EA must be "sold" directly to the communities that matter, from a coordinated, proactive messaging perspective that takes BOTH the Program-level value drivers AND the broader Agency mission and IT maturity context into consideration. Selling EA means persuading others to take additional time and possibly assign additional resources, for a mix of direct and indirect benefits – many of which aren't likely to be realized in the short-term. This means there's probably little current, allocated budget to work with; ergo the challenge of trying to sell an "unfunded mandate". Also, the concept of "Enterprise" in large Departments like Homeland Security tends to cross all kinds of organizational boundaries – as Richard Spires recently indicated by commenting that "...organizational boundaries still trump functional similarities. Most people understand what we're trying to do internally, and at a high level they get it. The problem, of course, is when you get down to them and their system and the fact that you're going to be touching them...there's always that fear factor," Spires said. It is quite clear to the Federal IT Investment community that for EA to meet its objective, understandable, relevant value must be measured and reported using a repeatable method – as described by GAO's recent report "Enterprise Architecture Value Needs To Be Measured and Reported". What's not clear is the method or guidance to sell this value. In fact, the current GAO "Framework for Assessing and Improving Enterprise Architecture Management (Version 2.0)", a.k.a. the "EAMMF", does not include words like "sell", "persuade", "market", etc., except in reference ("within Core Element 19: Organization business owner and CXO representatives are actively engaged in architecture development") to a brief section in the CIO Council's 2001 "Practical Guide to Federal Enterprise Architecture", entitled "3.3.1. Develop an EA Marketing Strategy and Communications Plan." Furthermore, Core Element 19 of the EAMMF is advised to be applied in "Stage 3: Developing Initial EA Versions". This kind of EA sales campaign truly should start much earlier in the maturity progress, i.e. in Stages 0 or 1. So, what are the understandable, relevant benefits (or value) to sell, that can find an agreeable, participatory audience, and can pave the way towards success of a longer-term, funded set of EA mechanisms that can be methodically measured and reported? Pragmatic benefits from a useful EA that can help overcome the fear of change? And how should they be sold? Following is a brief taxonomy (it's a taxonomy, to help organize SME support) of benefit-related subjects that might make the most sense, in creating the messages and organizing an initial "engagement plan" for evangelizing EA "from within". An EA "Sales Taxonomy" of sorts. We're not boiling the ocean here; the subjects that are included are ones that currently appear to be urgently relevant to the current Federal IT Investment landscape. Note that successful dialogue in these topics is directly usable as input or guidance for actually developing early-stage, "Fit-for-Purpose" (a DoDAF term) Enterprise Architecture artifacts, as prescribed by common methods found in most EA methodologies, including FEAF, TOGAF, DoDAF and our own Oracle Enterprise Architecture Framework (OEAF). The taxonomy below is organized by (1) Target Community, (2) Benefit or Value, and (3) EA Program Facet - as in: "Let's talk to (1: Community Member) about how and why (3: EA Facet) the EA program can help with (2: Benefit/Value)". Once the initial discussion targets and subjects are approved (that can be measured and reported), a "marketing and communications plan" can be created. A working example follows the Taxonomy. Enterprise Architecture Sales Taxonomy Draft, Summary Version 1. Community 1.1. Budgeted Programs or Portfolios Communities of Purpose (CoPR) 1.1.1. Program/System Owners (Senior Execs) Creating or Executing Acquisition Plans 1.1.2. Program/System Owners Facing Strategic Change 1.1.2.1. Mandated 1.1.2.2. Expected/Anticipated 1.1.3. Program Managers - Creating Employee Performance Plans 1.1.4. CO/COTRs – Creating Contractor Performance Plans, or evaluating Value Engineering Change Proposals (VECP) 1.2. Governance & Communications Communities of Practice (CoP) 1.2.1. Policy Owners 1.2.1.1. OCFO 1.2.1.1.1. Budget/Procurement Office 1.2.1.1.2. Strategic Planning 1.2.1.2. OCIO 1.2.1.2.1. IT Management 1.2.1.2.2. IT Operations 1.2.1.2.3. Information Assurance (Cyber Security) 1.2.1.2.4. IT Innovation 1.2.1.3. Information-Sharing/ Process Collaboration (i.e. policies and procedures regarding Partners, Agreements) 1.2.2. Governing IT Council/SME Peers (i.e. an "Architects Council") 1.2.2.1. Enterprise Architects (assumes others exist; also assumes EA participants aren't buried solely within the CIO shop) 1.2.2.2. Domain, Enclave, Segment Architects – i.e. the right affinity group for a "shared services" EA structure (per the EAMMF), which may be classified as Federated, Segmented, Service-Oriented, or Extended 1.2.2.3. External Oversight/Constraints 1.2.2.3.1. GAO/OIG & Legal 1.2.2.3.2. Industry Standards 1.2.2.3.3. Official public notification, response 1.2.3. Mission Constituents Participant & Analyst Community of Interest (CoI) 1.2.3.1. Mission Operators/Users 1.2.3.2. Public Constituents 1.2.3.3. Industry Advisory Groups, Stakeholders 1.2.3.4. Media 2. Benefit/Value (Note the actual benefits may not be discretely attributable to EA alone; EA is a very collaborative, cross-cutting discipline.) 2.1. Program Costs – EA enables sound decisions regarding... 2.1.1. Cost Avoidance – a TCO theme 2.1.2. Sequencing – alignment of capability delivery 2.1.3. Budget Instability – a Federal reality 2.2. Investment Capital – EA illuminates new investment resources via... 2.2.1. Value Engineering – contractor-driven cost savings on existing budgets, direct or collateral 2.2.2. Reuse – reuse of investments between programs can result in savings, chargeback models; avoiding duplication 2.2.3. License Refactoring – IT license & support models may not reflect actual or intended usage 2.3. Contextual Knowledge – EA enables informed decisions by revealing... 2.3.1. Common Operating Picture (COP) – i.e. cross-program impacts and synergy, relative to context 2.3.2. Expertise & Skill – who truly should be involved in architectural decisions, both business and IT 2.3.3. Influence – the impact of politics and relationships can be examined 2.3.4. Disruptive Technologies – new technologies may reduce costs or mitigate risk in unanticipated ways 2.3.5. What-If Scenarios – can become much more refined, current, verifiable; basis for Target Architectures 2.4. Mission Performance – EA enables beneficial decision results regarding... 2.4.1. IT Performance and Optimization – towards 100% effective, available resource utilization 2.4.2. IT Stability – towards 100%, real-time uptime 2.4.3. Agility – responding to rapid changes in mission 2.4.4. Outcomes –measures of mission success, KPIs – vs. only "Outputs" 2.4.5. Constraints – appropriate response to constraints 2.4.6. Personnel Performance – better line-of-sight through performance plans to mission outcome 2.5. Mission Risk Mitigation – EA mitigates decision risks in terms of... 2.5.1. Compliance – all the right boxes are checked 2.5.2. Dependencies –cross-agency, segment, government 2.5.3. Transparency – risks, impact and resource utilization are illuminated quickly, comprehensively 2.5.4. Threats and Vulnerabilities – current, realistic awareness and profiles 2.5.5. Consequences – realization of risk can be mapped as a series of consequences, from earlier decisions or new decisions required for current issues 2.5.5.1. Unanticipated – illuminating signals of future or non-symmetric risk; helping to "future-proof" 2.5.5.2. Anticipated – discovering the level of impact that matters 3. EA Program Facet (What parts of the EA can and should be communicated, using business or mission terms?) 3.1. Architecture Models – the visual tools to be created and used 3.1.1. Operating Architecture – the Business Operating Model/Architecture elements of the EA truly drive all other elements, plus expose communication channels 3.1.2. Use Of – how can the EA models be used, and how are they populated, from a reasonable, pragmatic yet compliant perspective? What are the core/minimal models required? What's the relationship of these models, with existing system models? 3.1.3. Scope – what level of granularity within the models, and what level of abstraction across the models, is likely to be most effective and useful? 3.2. Traceability – the maturity, status, completeness of the tools 3.2.1. Status – what in fact is the degree of maturity across the integrated EA model and other relevant governance models, and who may already be benefiting from it? 3.2.2. Visibility – how does the EA visibly and effectively prove IT investment performance goals are being reached, with positive mission outcome? 3.3. Governance – what's the interaction, participation method; how are the tools used? 3.3.1. Contributions – how is the EA program informed, accept submissions, collect data? Who are the experts? 3.3.2. Review – how is the EA validated, against what criteria?  Taxonomy Usage Example:   1. To speak with: a. ...a particular set of System Owners Facing Strategic Change, via mandate (like the "Cloud First" mandate); about... b. ...how the EA program's visible and easily accessible Infrastructure Reference Model (i.e. "IRM" or "TRM"), if updated more completely with current system data, can... c. ...help shed light on ways to mitigate risks and avoid future costs associated with NOT leveraging potentially-available shared services across the enterprise... 2. ....the following Marketing & Communications (Sales) Plan can be constructed: a. Create an easy-to-read "Consequence Model" that illustrates how adoption of a cloud capability (like elastic operational storage) can enable rapid and durable compliance with the mandate – using EA traceability. Traceability might be from the IRM to the ARM (that identifies reusable services invoking the elastic storage), and then to the PRM with performance measures (such as % utilization of purchased storage allocation) included in the OMB Exhibits; and b. Schedule a meeting with the Program Owners, timed during their Acquisition Strategy meetings in response to the mandate, to use the "Consequence Model" for advising them to organize a rapid and relevant RFI solicitation for this cloud capability (regarding alternatives for sourcing elastic operational storage); and c. Schedule a series of short "Discovery" meetings with the system architecture leads (as agreed by the Program Owners), to further populate/validate the "As-Is" models and frame the "To Be" models (via scenarios), to better inform the RFI, obtain the best feedback from the vendor community, and provide potential value for and avoid impact to all other programs and systems. --end example -- Note that communications with the intended audience should take a page out of the standard "Search Engine Optimization" (SEO) playbook, using keywords and phrases relating to "value" and "outcome" vs. "compliance" and "output". Searches in email boxes, internal and external search engines for phrases like "cost avoidance strategies", "mission performance metrics" and "innovation funding" should yield messages and content from the EA team. This targeted, informed, practical sales approach should result in additional buy-in and participation, additional EA information contribution and model validation, development of more SMEs and quick "proof points" (with real-life testing) to bolster the case for EA. The proof point here is a successful, timely procurement that satisfies not only the external mandate and external oversight review, but also meets internal EA compliance/conformance goals and therefore is more transparently useful across the community. In short, if sold effectively, the EA will perform and be recognized. EA won’t therefore be used only for compliance, but also (according to a validated, stated purpose) to directly influence decisions and outcomes. The opinions, views and analysis expressed in this document are those of the author and do not necessarily reflect the views of Oracle.

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  • Recommend a basic 3D graphics card for HP ProLiant DL360 G5?

    - by arathorn
    We've got an HP ProLiant DL360 G5 running Windows Server 2008 R2 that needs a graphics card with 3D acceleration (the integrated ATI ES1000 graphics don't have this). This is an unfortunate requirement that we can't avoid, as it is required by S/W installed on the server that is beyond our control. Looks like the PCI-Express slots in the box are x8 (1 full and 1 low profile). We just need a basic card, as long as it has the 3D acceleration. Any recommendations?

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  • What is the best SOHO NAS currently available?

    - by VinceJS
    What is the "best" Small Office Home Office (SOHO) Network Attached Storage (NAS) device available? Best performance vs. cost that is! I am looking for one that I can use at home to safely store my pictures, videos. What features should I look for? There are so many NAS reviews on the web, how do you choose the right one?

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  • What is the best SOHO NAS currently available?

    - by VinceJS
    What is the "best" Small Office Home Office (SOHO) Network Attached Storage (NAS) device available? Best performance vs. cost that is! I am looking for one that I can use at home to safely store my pictures, videos. What features should I look for? There are so many NAS reviews on the web, how do you choose the right one?

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  • restore Ubuntu desktop

    - by target
    Hi, Few days back, I installed compis to try out the 3d desktop. Unfortunately, that messed up my desktop, and it has since been working in low resolution mode. Can someone suggest a quick restore mechanism to get my desktop display back to normal. Many thanks, Target

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  • Firefox 3.5.6 causes entire computer to freeze

    - by Anthony Aziz
    Here's the situation: Environment: Just installed a fresh copy of Win7 Pro 32-bit to NTFS partition on 750GB SATA drive Hardware: E8400 3GHz ASUS P5QL Pro 4GB DDR2 1066 RAM EVGA 9800 GTX+ Plenty of cooling, no problems with hardware before Data is stored on a separate partition, including My Documents No security software is yet installed No extensions installed yet Problem: While using Firefox, sometimes the entire computer will freeze/hang. I get no mouse or keyboard input, can't CTRL+ALT+DEL, no "not responding" indication, just a static image on my display. My drivers are all up to date as far as I'm aware (I just installed this copy of Windows last week). I first noticed this when trying to install Xmarks. I went to the Xmarks site and tried to install and it would freeze. I managed to get it installed (Safe mode and the Mozilla addon site worked), but when I go to configure it (log in, etc), the computer freezes. I don't think it's a matter of usage time or memory issues, because while testing, I browsed wallpaper galleries for about 30 minutes, sometimes as many as 12-15 tabs open at a time, without issue. Sometimes I won't even try to install Xmarks at it will hang. I can install (some) other extensions, the only one I've tried is download status bar (which works). What I've done to try to fix: Restarted (duh) Windows safe mode Completely remove Firefox and install it to a new directory, according to Mozilla's KB (I haven't tried the profile manager, though I assume this does the same thing, except perhaps more thoroughly) Some BIOS changes, including Power options, disabling oveclocking (it was a modest overclock on the CPU, which has run Win7 beta and RC for almost a year now) Memtest Used another Windows user profile, same tragic results I'm STUCK now, with no idea what to do. I'm using Chrome as my main browser at the moment, but that's not something I want to be stuck with. I like Firefox and want to use it. I'm going to try creating a new profile first. One thing I did notice: I started leaving task manager and performance monitor open when anticipating (but dreading) a freeze. firefox.exe had low CPU and low memory, but it looked like overall disk usage was seeing some spikes on the small graph Performance Monitor gives you. I saw on one blog post a fellow using XP moved his Local Settings directory from a separate drive to his main drive, and that solved it, but I don't think my AppData directory is on my D: drive, and that's on the same physical device anyways. Still, something that might be worth trying. I'd extremely appreciate any help. Thanks very much. I really don't want to reinstall Windows from scratch again :( Anthony Aziz

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  • What is the difference between Anycast and GeoDNS / GeoIP wrt HA?

    - by Riyad
    Based on the Wikipedia description of Anycast, it includes both the distribution of a domain-name-to-many-IP-mapping across many DNS servers as well as replying to clients with the most geographically close (or fastest) server. In the context of a globally distributed, highly available site like google.com (or any CDN service with many global edge locations) this sounds like the two key features one would need. DNS services like Amazon's Route53, EasyDNS and DNSMadeEasy all advertise themselves as Anycast-enabled networks. Therefore my assumption is that each of these DNS services transparently offer me those two killer features: multi-IP-to-domain mapping AND routing clients to the closest node. However, each of these services seem to separate out these two functionalities, referring to the 2nd one (routing clients to closest node) as "GeoDNS", "GeoIP" or "Global Traffic Director" and charge extra for the service. If a core tenant of an Anycast-capable system is to already do this, why is this functionality being earmarked as this extra feature? What is this "GeoDNS" feature doing that a standard Anycast DNS service won't do (according to the definition of Anycast from Wikipedia -- I understand what is being advertised, just not why it isn't implied already). I get extra-confused when a DNS service like Route53 that doesn't support this nebulous "GeoDNS" feature lists functionality like: Fast – Using a global anycast network of DNS servers around the world, Route 53 is designed to automatically route your users to the optimal location depending on network conditions. As a result, the service offers low query latency for your end users, as well as low update latency for your DNS record management needs. ... which sounds exactly like what GeoDNS is intended to do, but geographically directing clients is something they explicitly don't support it yet. Ultimately I am looking for the two following features from a DNS provider: Map multiple IP addresses to a single domain name (like google.com, amazon.com, etc. does) Utilize a DNS service that will respond to client requests for that domain with the IP address of the nearest server to the requestee. As mentioned, it seems like this is all part of an "Anycast" DNS service (all of which these services are), but the features and marketing I see from them suggest otherwise, making me think I need to learn a bit more about how DNS works before making a deployment choice. Thanks in advance for any clarifications.

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  • Open file - Security warning

    - by joker
    Does anyone know how to disable the unknown publisher security warning when running an application in Windows Xp Home? It's pretty annoying to have to click run everytime... I have tried: Run gpedit.msc, and go to Local Computer Policy-User Configuration-Administrative Templates-Windows Components-Attachment Manager and enable "Default risk level for file attachments", and then enable "Inclusion list for low risk file types" and add to this list the file extensions that you want to open without triggering this crap. But this file 'gpedit.msc' doest not exist on my computer, i checked system32 folder also =/ maybe its for xp pro

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  • TF2 with Parallels on a MacBook Pro

    - by Eric Koslow
    I am trying to get TF2 to run under Parallels on my 15'' MacBook Pro, but it is ultimatly failing. To get any decent frame rate I have to put all the setting to low, but even then I get weird graphical "gliches" when I play. Controlls are unresponsive and very laggy as well. I have increased the video memory to 256mb, but that doesn't seem to have helped. What else should I do to make the game playable?

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