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  • Remove automatic Aero disabling in Windows 7

    - by Jani Hartikainen
    Sometimes when I'm playing games which are heavy on the GPU, Windows decides to helpfully disable aero, causing everything to freeze for a bit and in the worst case, combined with ATI's brilliant drivers, causes the game to crash. So, How do I stop Windows from automatically disabling Aero when playing games? It has absolutely no effect on the performance of the game itself when it does that. Also, I'd like to get rid of the "You should disable Aero to improve performance" helpful hint popup which sometimes shows up. But I suppose getting rid of the first will get rid of the second, assuming anyone knows how.

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  • Running nph-script.cgi keeps outputting Server details at the end

    - by wgewweg
    I am running a nph-script.cgi on my server. The server keeps adding HTTP/1.1 200 OK Date: Thu, 05 Nov 2009 02:28:53 GMT Server: Apache/2.2.8 (Ubuntu) PHP/5.2.8-1hardy~ppa1 with Suhosin-Patch mod_perl/2.0.3 Perl/v5.8.8 Content-Length: 0 Keep-Alive: timeout=15, max=100 Connection: Keep-Alive Content-Type: text/plain X-Pad: avoid browser bug At the bottom of each page loaded via the .cgi script. why is this the case? How do I remove this annoying message that is appended to all pages ?

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  • Install Domain Controller – Part1 of build my own development SharePoint2010 Farm

    - by ybbest
    As the memory become really cheap now, a couple days ago I have updated my laptop memory to 12g. Plus I got my old desktop ,now I decide to build my own SharePoint farm at home. I decide to document the steps to build a simple SharePoint farm. I will use windows server 2008 r2 and VMware. In the first part of this series of building my own SharePoint farm. I will create my domain controller. Here are the steps to install it: Open the command line by going to run and type CMD and then type dcpromo in the command line. The AD Installation wizard will prompt and click next. 2. Click next as shown in the screenshot.   3. Select creates a new domain in a new forest and click next.      4. Type a domain name (e.g. ybbest.com) and click next. 5.In my case , I select Windows Server 2008 R2 forest Functional level and click next 6. Leave the default and click next.(If you have not make a static IP address , you need to do so now)      7.You might get scary prompt like the screenshot below , just ignore the message and click Yes.     8.Leave the default settings and click Next  9.Type a password when you need to restore your Domain        10.Click Next and restart your computer ,this will install your Domain Controller.

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  • Follow point of interest by applying torque

    - by azymm
    Given a body with an orientation angle and a point of interest or targetAngle, is there an elegant solution for keeping the body oriented towards the point of interest by applying torque or impulses? I have a naive solution working below, but the effect is pretty 'wobbly', it'll overshoot each time, slowly getting closer to the target angle - undesirable effect in my case. I'd like to find a solution that is more intelligent - that can accelerate to near the target angle then decelerate and stop right at the target angle (or within a small range). If it helps, I'm using box2d and the body is a rectangle. def gameloop(dt): targetAngle = get_target_angle() bodyAngle = get_body_angle() deltaAngle = targetAngle - bodyAngle if deltaAngle > PI: deltaAngle = targetAngle - (bodyAngle + 2.0 * PI) if deltaAngle < -PI: deltaAngle = targetAngle - (bodyAngle - 2.0 * PI) # multiply by 2, for stronger reaction deltaAngle = deltaAngle * 2.0; body.apply_torque(deltaAngle); One other thing, when body has no linear velocity, the above solution works ok. But when the body has some linear velocity, the solution above causes really wonky movement. Not sure why, but would appreciate any hints as to why that might be.

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  • Can't create VM with virt-install on Debian wheezy

    - by chrismacp
    Cant find any answers anywhere so here goes. I am trying to CREATE a new virtual machine using the virt-install command from a console on a Debian wheezy install. I keep getting the following output: Starting install... ERROR internal error process exited while connecting to monitor: char device redirected to /dev/pts/1 inet_listen_opts: bind(ipv4,127.0.0.1,5951): Cannot assign requested address inet_listen_opts: FAILED I assumed that the port (5951 in this case) was being used judging by the error message and other sites I visited for an answer, but the same error occurs whatever number I use for the port. I cant see that port being listened upon in netstat either. Anyone have any ideas what may be wrong?

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  • How to Backup Your Web-Based Email Account Using Thunderbird

    - by Jason Fitzpatrick
    If the Gmail scare earlier this week has you thinking about backing up your Gmail or other web-based email account, we’re here to help. Read on to learn how to backup your web-based email using open source email application Thunderbird. In case you missed it, earlier this week Gmail suffered an unusual series of glitches that led to 0.02% of Gmail users finding their inboxes totally empty. The good news is that the glitch was fixed and no actual data was lost (they restored the missing email from tape backups that were unaffected by the issue). While that’s wonderful nobody lost any important emails it’s also very unsettling. Not every “Oops, we lost your data!” scenario ends so well. Today we’re going to walk you through backing up your email using the free and robust open-source application Thunderbird. Latest Features How-To Geek ETC Have You Ever Wondered How Your Operating System Got Its Name? Should You Delete Windows 7 Service Pack Backup Files to Save Space? What Can Super Mario Teach Us About Graphics Technology? Windows 7 Service Pack 1 is Released: But Should You Install It? How To Make Hundreds of Complex Photo Edits in Seconds With Photoshop Actions How to Enable User-Specific Wireless Networks in Windows 7 Access the Options for Your Favorite Extensions Easier in Firefox Don’t Sleep Keeps Your Windows Machine Awake DropSpace Syncs Android Files to Dropbox Field of Poppies Wallpaper The History Of Operating Systems [Infographic] DriveSafe.ly Reads Your Text Messages Aloud

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  • Can't upgrade Windows Server 2012 Essentials to Windows Server 2012 R2 Essentials

    - by Magnus
    So today was RTM of Windows Server 2012 R2 Essentials released. I immediately tried to do an in-place upgrade of an existing RTM 2012 Essentials to RTM 2012 R2 Essentials, but get: Windows Server 2012 Essentials cannot be upgraded to Windows Server 2012 R2 Essentials. You can choose to install a new copy of Windows Server 2012 R2 Essentials instead, but this is different from an upgrade, and does not keep your files, settings, and programs. You’ll need to reinstall any programs using the original installation discs or files. To save your files before installing Windows, back them up to an external location such as a CD, DVD, or external hard drive. To install a new copy of Windows Server 2012 R2 Essentials, click the Back button in the upper left-hand corner, and select “Custom (advanced)”. This seems a bit odd, is this really the case? I can't find anything in the official documentation stating that this upgrade isn't possible.

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  • MacBookPro RAM: CL7 or CL9

    - by chris_l
    Hi, I want to increase the RAM in my MacBookPro 15", 2.53 GHz, Mid-2009. I currently have 4GB, and I want 6GB (and upgrade to 8GB later - I think this should work with my model: http://forums.macrumors.com/showthread.php?t=573906) Now I see two offers: 1x4GB DDR3 1333 CL9 9-9 (149 EUR) 1x4GB DDR3 1066 CL7 7-7 (192 EUR). Both are from the same brand (Transcend), both are labeled "For MacBook/MacBookPro". Now I have no idea, which of these would work better with the 2GB RAM module from my currently installed memory (Running at 1067 MHz, according to System Profiler - but with what CL setting?) Would the 1333 CL9 RAM be set to CL7 when running at 1066 MHz? Thanks, Chris PS Should I expect problems when I later upgrade to 8GB with a different module (in case the same module won't be produced anymore)?

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  • Kickstart PXE Boot Installation not working

    - by Anshuman
    I tried installing PXE Boot Installation Server on RHEL 6.0. I seem to have done everything according to the page: http://www.linux-sxs.org/internet_serving/pxeboot.html. In my case, the client boots, gets DHCP IP address from our server, connects to the Kickstart server too, but then nothing happens. It shows: Loading 192.168.1.101: pxe.linux.0 ..... 192.168.1.101 in my kickstart server. Did any one face such a situation? I'm using a test env on Oracle Virtualbox with DNS Server on RHEL 6.0, DHCP Server on CentOS 6.0 and Kickstart server on RHEL 6.0. The image I'm trying to install is that of REHL 6.0! Awaiting some responses! Cheers, Anshuman

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  • Windows CE: SDK Doesn’t Show up in Visual Studio 2008

    - by Bruce Eitman
    A customer recently contacted me because after installing an SDK it didn’t show up in Visual Studio 2008.  So being a good vendor I installed VS2008 and then installed the SDK – no problem the SDK showed up and I could create projects based on it. I let the customer know that the SDK definitely works with VS2008. The customer got back to me and asked what OS I was using. Hmm, how could that play into this? I told him that I use Windows XP, and it turned out that he is way more modern than I am and is using both Windows Vista and 7. The customer opened a support case with Microsoft. The answer turns out to be that the SDK install requires the user to be logged on as an administrator when installing on Windows Vista and 7 for the SDK to show up in Visual Studio 2008. This problem does not seem to exist for Visual Studio 2005 on those operating systems. The actual instructions from Microsoft Support are: 1)      Make sure Visual Studio 2008 is not running. I also shut down the device emulator manager but you may not be using that. 2)      Open a “Visual Studio 2008 Command Prompt” as Administrator. On Windows 7 just right click the short cut and pick the “Run as administrator” option. 3)      Enter the following command: msiexec /log SDKInstallLog.txt /package <the path to your .msi file> 4)      When asked if you wish to do a custom or complete install pick custom 5)      Instruct the installer to omit the installation of the documentation. This was something I found about CE 6 SDK installation issue and may have no bearing upon your problem but I did it anyway. 6)      Install   Copyright © 2010 – Bruce Eitman All Rights Reserved

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  • Option Trading: Getting the most out of the event session options

    - by extended_events
    You can control different aspects of how an event session behaves by setting the event session options as part of the CREATE EVENT SESSION DDL. The default settings for the event session options are designed to handle most of the common event collection situations so I generally recommend that you just use the defaults. Like everything in the real world though, there are going to be a handful of “special cases” that require something different. This post focuses on identifying the special cases and the correct use of the options to accommodate those cases. There is a reason it’s called Default The default session options specify a total event buffer size of 4 MB with a 30 second latency. Translating this into human terms; this means that our default behavior is that the system will start processing events from the event buffer when we reach about 1.3 MB of events or after 30 seconds, which ever comes first. Aside: What’s up with the 1.3 MB, I thought you said the buffer was 4 MB?The Extended Events engine takes the total buffer size specified by MAX_MEMORY (4MB by default) and divides it into 3 equally sized buffers. This is done so that a session can be publishing events to one buffer while other buffers are being processed. There are always at least three buffers; how to get more than three is covered later. Using this configuration, the Extended Events engine can “keep up” with most event sessions on standard workloads. Why is this? The fact is that most events are small, really small; on the order of a couple hundred bytes. Even when you start considering events that carry dynamically sized data (eg. binary, text, etc.) or adding actions that collect additional data, the total size of the event is still likely to be pretty small. This means that each buffer can likely hold thousands of events before it has to be processed. When the event buffers are finally processed there is an economy of scale achieved since most targets support bulk processing of the events so they are processed at the buffer level rather than the individual event level. When all this is working together it’s more likely that a full buffer will be processed and put back into the ready queue before the remaining buffers (remember, there are at least three) are full. I know what you’re going to say: “My server is exceptional! My workload is so massive it defies categorization!” OK, maybe you weren’t going to say that exactly, but you were probably thinking it. The point is that there are situations that won’t be covered by the Default, but that’s a good place to start and this post assumes you’ve started there so that you have something to look at in order to determine if you do have a special case that needs different settings. So let’s get to the special cases… What event just fired?! How about now?! Now?! If you believe the commercial adage from Heinz Ketchup (Heinz Slow Good Ketchup ad on You Tube), some things are worth the wait. This is not a belief held by most DBAs, particularly DBAs who are looking for an answer to a troubleshooting question fast. If you’re one of these anxious DBAs, or maybe just a Program Manager doing a demo, then 30 seconds might be longer than you’re comfortable waiting. If you find yourself in this situation then consider changing the MAX_DISPATCH_LATENCY option for your event session. This option will force the event buffers to be processed based on your time schedule. This option only makes sense for the asynchronous targets since those are the ones where we allow events to build up in the event buffer – if you’re using one of the synchronous targets this option isn’t relevant. Avoid forgotten events by increasing your memory Have you ever had one of those days where you keep forgetting things? That can happen in Extended Events too; we call it dropped events. In order to optimizes for server performance and help ensure that the Extended Events doesn’t block the server if to drop events that can’t be published to a buffer because the buffer is full. You can determine if events are being dropped from a session by querying the dm_xe_sessions DMV and looking at the dropped_event_count field. Aside: Should you care if you’re dropping events?Maybe not – think about why you’re collecting data in the first place and whether you’re really going to miss a few dropped events. For example, if you’re collecting query duration stats over thousands of executions of a query it won’t make a huge difference to miss a couple executions. Use your best judgment. If you find that your session is dropping events it means that the event buffer is not large enough to handle the volume of events that are being published. There are two ways to address this problem. First, you could collect fewer events – examine you session to see if you are over collecting. Do you need all the actions you’ve specified? Could you apply a predicate to be more specific about when you fire the event? Assuming the session is defined correctly, the next option is to change the MAX_MEMORY option to a larger number. Picking the right event buffer size might take some trial and error, but a good place to start is with the number of dropped events compared to the number you’ve collected. Aside: There are three different behaviors for dropping events that you specify using the EVENT_RETENTION_MODE option. The default is to allow single event loss and you should stick with this setting since it is the best choice for keeping the impact on server performance low.You’ll be tempted to use the setting to not lose any events (NO_EVENT_LOSS) – resist this urge since it can result in blocking on the server. If you’re worried that you’re losing events you should be increasing your event buffer memory as described in this section. Some events are too big to fail A less common reason for dropping an event is when an event is so large that it can’t fit into the event buffer. Even though most events are going to be small, you might find a condition that occasionally generates a very large event. You can determine if your session is dropping large events by looking at the dm_xe_sessions DMV once again, this time check the largest_event_dropped_size. If this value is larger than the size of your event buffer [remember, the size of your event buffer, by default, is max_memory / 3] then you need a large event buffer. To specify a large event buffer you set the MAX_EVENT_SIZE option to a value large enough to fit the largest event dropped based on data from the DMV. When you set this option the Extended Events engine will create two buffers of this size to accommodate these large events. As an added bonus (no extra charge) the large event buffer will also be used to store normal events in the cases where the normal event buffers are all full and waiting to be processed. (Note: This is just a side-effect, not the intended use. If you’re dropping many normal events then you should increase your normal event buffer size.) Partitioning: moving your events to a sub-division Earlier I alluded to the fact that you can configure your event session to use more than the standard three event buffers – this is called partitioning and is controlled by the MEMORY_PARTITION_MODE option. The result of setting this option is fairly easy to explain, but knowing when to use it is a bit more art than science. First the science… You can configure partitioning in three ways: None, Per NUMA Node & Per CPU. This specifies the location where sets of event buffers are created with fairly obvious implication. There are rules we follow for sub-dividing the total memory (specified by MAX_MEMORY) between all the event buffers that are specific to the mode used: None: 3 buffers (fixed)Node: 3 * number_of_nodesCPU: 2.5 * number_of_cpus Here are some examples of what this means for different Node/CPU counts: Configuration None Node CPU 2 CPUs, 1 Node 3 buffers 3 buffers 5 buffers 6 CPUs, 2 Node 3 buffers 6 buffers 15 buffers 40 CPUs, 5 Nodes 3 buffers 15 buffers 100 buffers   Aside: Buffer size on multi-processor computersAs the number of Nodes or CPUs increases, the size of the event buffer gets smaller because the total memory is sub-divided into more pieces. The defaults will hold up to this for a while since each buffer set is holding events only from the Node or CPU that it is associated with, but at some point the buffers will get too small and you’ll either see events being dropped or you’ll get an error when you create your session because you’re below the minimum buffer size. Increase the MAX_MEMORY setting to an appropriate number for the configuration. The most likely reason to start partitioning is going to be related to performance. If you notice that running an event session is impacting the performance of your server beyond a reasonably expected level [Yes, there is a reasonably expected level of work required to collect events.] then partitioning might be an answer. Before you partition you might want to check a few other things: Is your event retention set to NO_EVENT_LOSS and causing blocking? (I told you not to do this.) Consider changing your event loss mode or increasing memory. Are you over collecting and causing more work than necessary? Consider adding predicates to events or removing unnecessary events and actions from your session. Are you writing the file target to the same slow disk that you use for TempDB and your other high activity databases? <kidding> <not really> It’s always worth considering the end to end picture – if you’re writing events to a file you can be impacted by I/O, network; all the usual stuff. Assuming you’ve ruled out the obvious (and not so obvious) issues, there are performance conditions that will be addressed by partitioning. For example, it’s possible to have a successful event session (eg. no dropped events) but still see a performance impact because you have many CPUs all attempting to write to the same free buffer and having to wait in line to finish their work. This is a case where partitioning would relieve the contention between the different CPUs and likely reduce the performance impact cause by the event session. There is no DMV you can check to find these conditions – sorry – that’s where the art comes in. This is  largely a matter of experimentation. On the bright side you probably won’t need to to worry about this level of detail all that often. The performance impact of Extended Events is significantly lower than what you may be used to with SQL Trace. You will likely only care about the impact if you are trying to set up a long running event session that will be part of your everyday workload – sessions used for short term troubleshooting will likely fall into the “reasonably expected impact” category. Hey buddy – I think you forgot something OK, there are two options I didn’t cover: STARTUP_STATE & TRACK_CAUSALITY. If you want your event sessions to start automatically when the server starts, set the STARTUP_STATE option to ON. (Now there is only one option I didn’t cover.) I’m going to leave causality for another post since it’s not really related to session behavior, it’s more about event analysis. - Mike Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • //TODO: Test this thoroughly!!!!!!

    - by Edward Boyle
    I just ran into an ugly sight in my code: //TODO: Test this thoroughly!!!!!! private void ... I would very much like to go back in time and ask the past me what I meant, why did I add that TODO:? …And then, smack the s%#t out of him. No matter how much testing I do of this code I will always wonder if the past me found something. Was it actually that code or was it a calling method that may bring unwanted results. The fact that I find absolutely nothing wrong with the code makes it that much more haunting. The moral of the story; when you find something wrong and need to test it thoroughly, stay up another hour testing it. The clarity in your head at that moment, on that issue, at that specific moment in time, would take hours worth of commenting to justify not finishing it now. Maybe what I meant was: // TODO: Test this thoroughly!!!!!! // All seems fine but test it just in case, not to worry. private void ... Doubt it. -I’m screwed.

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  • Chroot with CentOS 5.3 + openssh 4.3p2

    - by Scud
    OS: CentOS 5.3, with openssh 4.3p2 Trying to set 'chroot' in ssh shell, but openssh version prior to 4.8 doesn't take below settings. yum update openssh open up to version 4.3 which is quite old. Doesn't CentOS support openssh 4.8 or up? If that's the case, how to set chroot with openssh 4.3? or is it better to just using FTP? My purpose is limit SFTP or FTP access to certain folder, not root folder. Thanks! Match group sftponly ChrootDirectory /home/%u X11Forwarding no AllowTcpForwarding no ForceCommand internal-sftp

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  • What happens when the USB key or SD card I've installed VMware ESXi on fails?

    - by ewwhite
    An SD (SDHC) card installed in an HP ProLiant DL380p Gen8 server running VMware ESXi just failed. I encountered some rather ominous looking messages on the vCenter console and in the HP ProLiant ILO event log... Lost connectivity to the device ... backing the boot filesystem. As a result, host configuration changes will not be saved to persistent storage. Embedded Flash/SD-CARD: Error writing media 0, physical block 848880: Stack Exception. VMware advocates the use of USB and SD (SDHC) boot devices for ESXi. It was one of the main reasons the smaller footprint ESXi was developed (versus the older ESX). I've spent much time highlighting the differences between ESXi's installable and embedded modes to coworkers and clients. However, these failures do seem to happen. In this case, this is my third instance. Luckily, this is a vSphere cluster with SAN storage. What steps should be taken to remediate this failure?

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  • Git - post-receive hook with git pull "Failed to find a valid git directory"

    - by ludicco
    It's very weird but when setting a git repository and creating a post-receive hook with: echo "--initializing hook--" cd ~/websites/testing echo "--prepare update--" git pull echo "--update completed--" the hook runs indeed, but it never manage to run git pull properly: 6bfa32c..71c3d2a master -> master --initializing hook-- --prepare update-- fatal: Not a git repository: '.' Failed to find a valid git directory. --update completed-- so I'm asking myself now, how it's possible to make the hook update the clone with post-receive? in this case the user running the processes is the same, and its everything inside the user folder so I really don't understand...because if if I go manually into cd ~/websites/testing git pull it works without any problem... any help on that would be pretty much appreciated Thanks a lot

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  • SOA Suite Integration: Part 2: A basic BPEL process

    - by Anthony Shorten
    This is the next in the series about SOA Suite integration with Oracle Utilities Application Framework. One of the first scenarios I am going to illustrate in this series is building a basic BPEL process using Web Service calls to the Oracle Utilities Application Framework. The scenario is this. I will pass in the userid and the BPEL process will call our the AS-User Web Service we created in Part 1. This is just a basic test and illustrate how to import the Web Service into SOA Suite. To use this scenario, you will need access to Oracle SOA Suite, access to a copy of any Oracle Utilities Application Framework based product and Oracle JDeveloper (to build the process). First of all you need to start Oracle JDeveloper and create a new SOA Project to house the BPEL process in. For the purposes of this example I will call the project simpleBPEL and verify that SOA is part of the project. I will select "Composite with BPEL" to denote it as a BPEL process. I can also the same process to create a Mediator or OSB project (refer to the JDeveloper documentation on these technologies). For this example I will use BPEL 1.1 as my specification standard (BPEL 2.0 can also be used if desired). I give the individual BPEL process as simpleBPEL (you can use a different name but I wanted to keep the project and process the same for this example). I will also build a Synchronous BPEL Process as I want a response from the Web Service. I will leave the defaults to save time. I have no have a blank canvas to build my BPEL process against. Note: for simplicity I am going to use as much defaulting as possible. In fact I am not going to specify an input schema for the incoming call as I will use the basic single field used by BPEL as default. The first step is to import the AS-User Web Service into my BPEL project. To do this I use the standard Web Service BPEL component from the Component Palette to import the WSDL into the BPEL project. Now the tricky part (a joke), you drag and drop the component from the Palette onto the right side of the canvas in the Partner Links swim lane. This swim lane is reserved for Partner Links that have a Partner Role (i.e. being called rather than calling). When you drop the Web Service onto the canvas the Create Web Service wizard is invoked to ask for details of the Web Service. At this point you give the BPEL node a name. I have used the name RetrieveUser as a name. I placed the WSDL URL from the XAI Inbound Service screen in the WSDL URL. Once you specify the URL you can press the Find existing WSDL's button to load the information into BPEL from the call. You will notice the Port Type is prefilled with the port from the WSDL. I also suggest that you check copy wsdl and it's dependent artifacts into the project if you intending to work on the BPEL process offline. If you do not check this your target application must be accessible when you work on the BPEL process (that is not always convenient). Note: For the perceptive of you will notice that the URL specified in this example is different to the URL in the last post. The reason is for the demonstrations I shifted to a new server and did not redo all of the past screen captures. If you copy the WSDL into the project you will get an information screen about Localize Files. It is just a confirmation screen. The last confirmation screen is a summary of the partner link (the main tab is locked for editing at this stage). At this stage you have successfully imported the Web Service. To complete the setup of the Web Service you need to set the credentials for the Web Service to use. Refer to the past post on how to do that. Now to use the Web Service. To call the Web Service (as it is just imported not connected to the BPEL process yet), you must add an Invoke action to your BPEL Process. To do this, select Invoke action from the BPEL Constructs zone on the Component Palette and drop it on the edit nodes between the receiveInput and replyOutput nodes This will create an empty Invoke action. You will notice some connectors on the Invoke node. Grab the node closest to your Web Service and drag it to connect the Invoke to your Web Service. This instructs BPEL to use the Invoke to call the Web Service. Once the Invoke action is connected to the Web Service an Edit Invoke edit dialog is displayed. At this point I suggest you name the Invoke node. It is important to name the nodes straightaway and name them appropriately for you to trace the logic. I used InvokeUser as the name in this example. To complete the node configuration you must create Variables to hold the input and output for the call. To do this clock on Automatically Create Input Variable on the Edit Invoke dialog. You will be presented with a default variable name. It uses the node name (that is why it is important to name the node before hitting this button) as a prefix. You can name the variable anything but I usually take the default. Repeat the same for the output variable. You now have a completed node for invoking the service. You have a very basic BPEL process which contains an input, invoke and output node. It is not complete yet though. You need to tell the BPEL process how to pass data from the input to the invoke step and how to take the output from the service call and pass it back to the service. You need to now add an Assign node to assign the input to the Web Service. To do this select Assign activity from BPEL Constructs zone in the Component Palette. Drag and drop the Assign activity between the receiveInput and InvokeUser nodes as you want to pass data between these two nodes. You have now added a new Assign node to your BPEL process Double clicking the node allows you to specify the name of the node. I use AssignUser to describe that I am assigning user data. On the Copy Rules tab you can specify the mapping between the input variable InputVariable/payload/process/input string and the input variable for the Web Service call. We are passing data from the input to BPEL to the relevant input variable on the Web Service. This is simply drag and drop between the two data structures. In the example, I am using the input to pass to the user element in my Web Service as the user is the primary key for the object. The fields become linked (which means data from source will be copied to target). Almost there. You now need to process the output from the Web Service call to the outputVariable of the client call. I have decided to pass back one piece of data, the name associated with the user by concatenating the firstName and lastName elements from the Web Service call. To do this I will use a Transform as it is not just a matter of an Assign action. It is a concatenation operation. This also illustrates how you can use BPEL functionality to transform data from a Web Service call. As with the other components you drag and drop the Transform component to the appropriate place in the BPEL process. In this case we want to transform the output from the Web Service call so we want it after the InvokeUser action and the replyOutput action. The Transform component is actually part of the Oracle Extensions to the BPEL specification. Double clicking the Transform node will allow you to name the node.  In this example I used TransformName. To complete the transform I need to tell the product the source of the transformation and the target of the transform. In the example this is the InvokeUser output variable. I also named the mapper file to TransformName. By clicking the + or pencil icon next to the map I can create the map. The mapping screen is shows the source and target schemas for me to map across. As with the assign I can map the relevant elements. In my example, I first map the firstName from the Web Service to the result element. As I want to concatenate the names, I drop the concat function on the call line. I now attach the last name to the function to indicate the concatenation of the field. By default the names will be concatenated with no space. To make the name legible I add a space between the field by clicking the function and adding a space in the call. I now have a completed mapping. I can now save the whole project as my BPEL process is now complete. As you can see the following happens: We accept input from the client (the userid for the call) in the receiveInput step. We assign that value to the input parameters for the Web Service call in the AssignUser step. We invoke the Web Service call to retrieve the data from the product in the InvokeUser step. We take the output from the InvokeUser step and concatenate the names in the TransformName step. We pass back the data in the replyOutput step. At this point we can deploy the BPEL process to the SOA Suite server. I will not cover this aspect as it really all SOA Suite specific (it is all done via Oracle JDeveloper). Now we need to test the service in SOA Suite. We will use the Fusion Middleware Control test facility. I will assume that credentials have also been setup as per our previous post (else you will get a 401 error). You navigate to the deployed BPEL process within Fusion Middleware Control and select the Test Service option. Specify some test data on the payload at the bottom of the Test Service screen. In my case I am returning my own userid information. On the response tab you will see the result. It works. You can verify the steps using the Audit trace facility on individual calls. As you can see this is a basic BPEL but you get the idea of importing the Web Service is pretty straightforward. You can create more sophisticated BPEL processes using the full facilities in Oracle SOA Suite. I just showed you the basic principals.

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  • Your Day-by-Day Guide to Agile PLM at Oracle OpenWorld 2012

    - by Kerrie Foy
    This year’s Oracle OpenWorld conference is nearly here, and we’re all excited about what we have planned! With five days of activities and customer presenters from market leaders and top innovators like The Coca-Cola Company, Starbucks, JDSU, Facebook, GlobalFoundries, and more, this is an event you don't want to miss. I've compiled this day-by-day guide to help anyone keep track of all the “Product Lifecycle Management and Product Value Chain” sessions and activities at OpenWorld 2012, September 30 – October 4 in San Francisco, California.  Monday, October 1 There are great networking activities on Sunday September 30, but PLM specific sessions start after general conference keynotes on Monday, October 1 at 10:45 a.m. at the InterContinental Hotel in room Telegraph Hill. In fact, most of our sessions this year will be held in this room, which is still close to the conference keynotes in Moscone, but just far enough away to allow some focused networking and discussions.   This first session, 10:45 – 11:45 a.m. is a joint session with the Agile and AutoVue teams, entitled “Streamline PLM Design-to-Manufacturing Processes with AutoVue Visualization Soltuions” featuring presenters from Oracle as well as joint AutoVue and Agile PLM customer GlobalFoundries. In the following 12:15 – 1:15 p.m. slot, there are two sessions to choose from, so if you have a team of representatives attending OpenWorld, you may consider splitting up to catch both of these: a) Our General Session will be held in the InterContinental Hotel Ballroom C, which will cover our complete enterprise PLM strategy, product updates, and roadmaps. It’s our pleasure to feature a customer keynote presentation from Chris Bedi, CIO, and Rajeev Sethi, Director IT Business Engagement, of JDSU. b) A focused session on integrating PLM with Engineering and Supply Chain Systems will be held on the second floor of Moscone West (next to the InterContinental) in room 2022. Join to discover how these types of integrations help companies manage common and integrated design information across all MCAD, ECAD, and software components. After a lunch break and perhaps a visit to the Demogrounds in Moscone West, select from two product roadmap sessions in the next time slot (3:15 – 4:15 p.m.): an Agile 9.3.x session located in the InterContinental’s Ballroom C, and an Agile PLM for Process session located back in the InterContinental’s Telegraph Room. Both sessions will have strong content around each product line’s latest releases, vision, and customer examples. We are very pleased to feature Daniel Soosai of Facebook in the A9 session and Vinnie D’Agostino of The Coca-Cola Company in the PLM for Process session. Afterwards, hang in there for one last session of the day from 4:45 – 5:45 p.m.; it’s an insightful discussion on leveraging Agile PLM as the Foundation for Enterprise Quality Management, and it’s sure to be one of the best. In the Telegraph Room, this session will feature Oracle experts, partner co-presenter David Bartlett from CPG Solutions, and customer co-presenter Thomas Crowe, CIO of PL Developments. Hear their experience around implementing collaborative, integrated solutions to ensure effective knowledge transfer throughout an organization, and how to perform analysis in real time to resolve product quality issues swiftly and efficiently. On Monday evening there will be plenty of industry, product, and partner dinners, so take advantage of all the networking opportunities and catch some great tunes at the 5 day Oracle OpenWorld Music Festival! Tuesday, October 2 Tuesday starts early with a special PLM Networking Brunch, sponsored by several partners, from 8:30 a.m. – 10:30 a.m. at the B Restaurant that sits atop Yerba Buena Gardens. You’ll have the unique opportunity to meet with like-minded industry peers and a PLM partner to discuss a topic of your choosing while enjoying a delicious meal. Registration is required, so to inquire about attending this brunch, please email Terri.Hiskey-AT-oracle.com. After wrapping up your conversations over brunch, head over to the Marriott Marquis in the Nob Hill CD room for a chance to experience the Oracle Product Lifecycle Analytics solution in a Hands-On Lab, open from 10:15 a.m. – 12:45 p.m. Experts will be there to answer your questions. Back in the InterContinental Hotel’s Telegraph room, the session on “Ideation and Requirements Management: Capturing the Voice of the Customer” begins at 11:45 a.m. – 12:45 p.m. This may be the session for you if you’re struggling with challenges like too many repositories of customer needs, requests, and ideas; limited visibility into which ideas are being advanced by customers and field resources; or if you’re unable to leverage internal expertise to expose effort and potential risks. This session will discuss how Agile PLM can help you overcome ideation challenges to deliver the right products to their targeted markets and fulfill customer desires. Next, from 1:15 – 2:15 p.m. join us for a session on Managing Profitable Innovation with Oracle Product Lifecycle Analytics. If you missed the Hands-on Lab, have more questions, or simply want to be inspired by the product’s forward-thinking vision and capabilities, this is a great opportunity to meet the progressive-minded executives behind the application. After this session, it may be a good opportunity to swing by the Demogrounds in Moscone West and visit the Agile PLM demos at exhibit booths #81 for Agile PLM for Discrete Manufacturing, #70 for Agile PLM for Process, and #82 for AutoVue and Agile PLM Enterprise Visualization. Check out the related Supply Chain Management booths close by if you’re interested - here's the map. There’s always lots to see and do around the exhibit area. But don’t forget the last session of the day from 5:00 p.m. – 6:00 p.m. in Telegraph Hill on Managing Product Innovation and Compliance in Life Science Companies, a “must-see” if you’re in this industry. Launching innovative products quickly is already a high-stakes challenge, but companies in the life sciences industry face uniquely severe consequences when new products don’t perform or comply as required. In recent years, more and more regulations have become mandatory, and new ones, such as REACH, are currently going into effect for several companies. Customer presenters from pharmaceutical leader Eli Lilly will share how they’ve leveraged Agile PLM to deliver high-quality, innovative products in a fast-paced, heavily regulated market environment. Tuesday evening unwind at the Supply Chain Management Reception from 6:00 – 8:00 p.m. at the premier boutique Roe Nightclub and Lounge, which is located about three blocks down on Howard Street (on the other side of Moscone from the InterContinental Hotel). Registration is required. Click here for the details.   Wednesday, October 3 We have another full line-up on Wednesday, so be ready for an action-packed day. We start with a session at 10:15 – 11:15 a.m. in the Telegraph Room where we have a session on “PLM for Consumer Products: Building an Engine for Quality and Innovation” with featured presenters from Starbucks and partner Kalypso. This is a rare opportunity to learn directly from Starbucks how they instill quality and innovation throughout their organization, products, and processes, leveraging PLM disciplines with strong support from their partner.  If you’re not in the consumer products industry, we recommend attending another session at 10:15 – 11:15 a.m. in Moscone West room 3005: “Eco-Enterprise Innovation Awards and the Business Case for Sustainability” featuring Jeff Henley, Oracle’s Chairman of the Board and Jon Chorley, Chief Sustainability Officer. Oracle will honor select customers with Oracle’s Eco-Enterprise Innovation award, which recognizes customers and their respective partners who rely on Oracle products to support their green business practices to reduce their environmental impact while improving business efficiencies and reducing costs. The awards presentation is followed by a panel discussion with customers and Oracle executives, who describe how these award-winning organizations are embracing environmental initiatives as a central part of their business strategy and how information technology plays a pivotal role. Next at 11:45 a.m. – 12:45 p.m. in Telegraph Hill attend our session devoted to exploring Product Lifecycle Management’s role in Software Lifecycle Management. This is a thought leadership session with Oracle experts in the field on the importance of change management, and we’ll discuss how Oracle has for years leveraged Agile PLM to develop Agile PLM. If software lifecycle management doesn’t apply to your business or you’d rather engage in some lively one-on-one discussions, we also have a “Supply Chain Meet the Experts” session in Moscone West Room 2001A. Product experts, thought leaders and executives will be on hand to discuss your questions/topics, so come prepared. This session tends to fill up fast so try to get in early. At 1:15 – 2:15 p.m. join us back in Telegraph Hill for a session focused on leveraging the Agile Product Portfolio Management application as the Product Development Master Schedule to improve efficiencies, optimize resources, and gain visibility across projects enterprise-wide to improve portfolio profitability. Customer presenters from Broadcom will explain how they’ve leveraged the product to enable a master schedule with enterprise-level, phase-gate program and project collaboration and resource optimization. Again in Telegraph Hill from 3:30 – 4:30 p.m. we have an interesting session with leading semiconductor customer LSI and partner Kalypso on how LSI leveraged Agile PLM to advance from homegrown applications to complete Product Value Chain Management. That type of transition can be challenging, and LSI details how they were able to achieve their goals and the value they gained along the journey – a fascinating account for any company interested in leveraging best practices to innovate their business processes and even end products. Lastly, we’ll wrap up in Telegraph Hill from 5:00 – 6:00 p.m. with a session on “Ensuring New Product Success by Achieving Excellence in New Product Introduction.” This is a cross-industry session, guaranteed to deliver insight in the often elusive practice of creating winning products, and we’re very excited about. According to IDC Manufacturing Insights analyst Joe Barkai, “Product Failures are not necessarily a result of bad ideas…they are a result of suboptimal decisions.” We’ll show you how to wire your business processes to enhance decision-making and maximize product potential. Now, quickly hit your hotel room to freshen up and then catch one of the many complimentary shuttles to the much-anticipated Oracle Customer Appreciation Event on Treasure Island. We have a very exciting show planned – check out what’s in store here. Thursday, October 4 PLM has a light schedule on Thursday this year with just one session, but this again is one of our best sessions on managing the Product Value Chain: at 11:15 a.m – 12:15 p.m.in Telegraph Hill, it’s a customer and partner driven session with Sonoco Products and Deloitte telling their story about how to achieve integrated change control by interfacing Agile PLM with Oracle E-Business Suite. Sonoco Products, a global manufacturer of consumer and industrial packaging materials, with its systems integrator, Deloitte, is doing this by implementing prebuilt integration (Oracle Design-to-Release Integration Pack for Agile Product Lifecycle Management for Process and Oracle Process) to integrate Agile with Oracle Product Hub/Oracle Product Information Management and Oracle E-Business Suite. This session presents a case study of how Sonoco is leveraging this solution to improve data quality and build a framework for stronger master data governance. Even though that ends our PLM line-up at OpenWorld, there will still be many sessions and activities at the conference, so visit the Oracle OpenWorld website to review agendas and build your schedule. And of course, download and bring this guide and the latest version of the Agile PLM Focus-On Document (available soon!). San Francisco is a wonderful city to explore, and we’re glad you’re considering joining the Agile PLM team at Oracle OpenWorld!  I hope to see you there! Follow me before the conference and on site for real-time updates about #OOW12 on Twitter @Kerrie_Foy or @AgilePLM.

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  • Cannot connect to Xen domU via VNC if X isn't installed on domU

    - by Hai Minh Nguyen
    I'm trying to build a Xen domU that can be connected through the Xen's VNC server. Below is the template (actually it's generated by OpenNebula): name = 'one-153' #O CPU_CREDITS = 256 memory = '128' bootloader = "/usr/bin/pygrub" disk = ['tap:aio:/home/oneadmin/cloud/one/var/153/images/disk.0,xvda,w',] vif = ['mac=02:00:c0:a8:00:03,bridge=virbr0',] vfb = ['type=vnc,vnclisten=slave1,vncdisplay=1,vncpasswd=v98KXdFN'] The problem is that I can't connect to the domU if it doesn't have X. In this case all I got is a blank screen. Besides, if the domU has X, the screen is still blank until the login prompt appears, while it should be like this. Some information that may be useful: The domU and the dom0 both run CentOS 5.5. If the domU has X, it can be connected even when both X and the domU's VNC server isn't running. The VNC client is RealVNC.

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  • How should you approach supporting rapidly-updating web browsers?

    - by Schnapple
    Today, Firefox 5 was released. If all goes according to plan, Firefox 7 will be out by the end of the year. Firefox has adopted the Google Chrome development model wherein version numbers are largely unimportant and so just supporting "the latest (publicly available) one" is probably the best strategy. But how do you best test that? As my QA guys have pointed out, if you tell the client that you support "the latest version" but a version comes out that breaks your site, then you have a problem because now you've stated you support a web browser you don't. And since both Firefox and Chrome now update themselves automatically, the average person probably has no clue or care what version they're running. And having them either not upgrade or roll back is nontrivial. I'm finding there are a number of organizations that mandate their employees use IE (the head of IT subscribes to the Microsoft school of thought), or mandate their employees use Firefox (the head of IT subscribes to the IE-is-insecure school of thought), so Chrome updating constantly was a non-issue. But now that Firefox is a member of that club, I can see this becoming a bigger issue soon. My guess, in the case of Firefox, would be that the Aurora channel is the key, but what is the best way to approach testing it? Should we fix anything that comes up as an issue in Aurora, or should we wait until closer to the scheduled release? Do people automate this sort of thing?

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  • Is there a way to track data structure dependencies from the database, through the tiers, all the way out to a web page?

    - by Sean Mickey
    When we design applications, we generally end up with the same tiered sets of data structures: A persistent data structure that is described using DDL and implemented as RDBMS tables and columns. A set of domain objects that consist primarily of data structures, usually combined with business-rule level logic, that are implemented in a programming language such as Java. A set of service layer interfaces that directly support use case implementations (which use the domain data structures as parameters), implemented as EJBs or something equivalent in another programming language. UI screens that allow users to C reate, R etrieve, U pdate, and (maybe) D elete all manner of data structures and graphs of data structures, with numerous screens and with multiple UI widgets, all structured to support the same data structures. But if you want to change the data structures in any of these tiers, it always seems extremely difficult to assess the impact(s) the change will have across the application. UML can help, but tracing through diagram after diagram is not a real solution to this problem. The best I have ever seen was a homespun data tracking spreadsheet document that listed all of the data structures and walked the relationships from tier-to-tier. Is there a tool or accepted approach that makes it easy to identify a data structure in any tier and easily obtain a list of all dependent: database table and column data structures domain object data structures service layer interface methods and parameter data structures screen & UI component data structures

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  • hosts file ignored, how to troubleshoot?

    - by Superbest
    The hosts file on Windows computers is used to bind certain name strings to specific IP addresses to override other name resolution methods. Often, one decides to change the hosts file, and discovers that the changes refuse to take effect, or that even old entries of the hosts file are ignored thereafter. A number of "gotcha" mistakes can cause this, and it can be frustrating to figure out which one. When faced with the problem of Windows ignoring a hosts file, what is a comprehensive troubleshoot protocol that may be followed? This question has duplicates on SO, such as hosts file seems to be ignored, HOSTS file being ignored, /etc/hosts file being ignored as well as numerous discussions elsewhere. However, these tend to deal with a specific case, and once whatever mistake the OP made is found out, the discussion is over. If you don't happen to have made the same error, such a discussion isn't very useful. So I thought it would be more helpful to have a general protocol for resolving all hosts-related issues that would cover all cases.

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  • MDX Studio download #mdx #ssas

    - by Marco Russo (SQLBI)
    Short version: the latest available version of MDX Studio can be downloaded from http://www.sqlbi.com/tools/mdx-studio/ Long version: Last week Stacia Misner twitted that the online version of MDX Studio was no longer available. It was hosted on http://mdx.mosha.com. It was a sad news, and it is also not good that nobody is maintaining the desktop version of MDX Studio. The latest release is the 0.4.14 and as I am writing it is still available on a SkyDrive link provided by Mosha Pasumansky, who wrote MDX Studio. Mosha does not work in Microsoft now and the entire BI community hopes that somebody will continue its work on this product. Unfortunately, it cannot be published on CodePlex because of some IP restrictions. Only bad news? Well, I hope no. The first good news is that MDX Studio also works with Analysis Services 2012 in Multidimensional mode. The second news is that, after having checked that we can do that, we created a web page on SQLBI web site to download the latest available release of MDX Studio. I hope it will be necessary to update it in the future, by now it is just a way to simplify the finding and download of this precious tool, and to grant that it will not disappear in case the current SkyDrive using to host the download would be discontinued, like it happened to the MDX Studio online version. Now a question to the BI Community: I know that there was some content available regarding tutorial on MDX Studio. I’d like to gather it and to put all in a single place. If you have such content, please contact me directly writing to marco (dot) russo (at) sqlbi [dot] com. Thanks!

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  • Collision detection with multiple polygons simultaneously

    - by Craig Innes
    I've written a collision system which detects/resolves collisions between a rectangular player and a convex polygon world using the Separating Axis Theorem. This scheme works fine when the player is colliding with a single polygon, but when I try to create a level made up of combinations of these shapes, the player gets "stuck" between shapes when trying to move from one polygon to the other. The reason for this seems to be that collisions are detected after the player has been pushed through the shape by its movement or gravity. When the system resolves the collision, it resolves them in an order that doesn't make sense (for example, when the player is moving from one flat rectangle to another, gravity pushes them below the ground, but the collision with the left hand side of the second block is resolved before the collision with the top of the block, meaning the player is pushed back left before being pushed back up). Other similar posts have resolved this problem by having a strict rule on which axes to resolve first. For example, always resolve the collision on the y axis, then if the object is still colliding with things, resolve on the x axis. This solution only works in the case of a completely axis oriented box world, and doesn't solve the problem if the player is stuck moving along a series of angled shapes or sliding down a wall. Does any one have any ideas of how I could alter my collision system to prevent these situations from happening?

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  • Setting alias in Windows PowerShell

    - by westsider
    In PowerShell, I type: PS C: sal cdp "cd 'C:\Users\ec\Documents\Visual Studio 2010\Projects'" I get no error from this, and PS C: gal cdp shows definition as: cd 'C:\Users\ec\Documents\Visual Studio 2010\Projects' But, when I try to use cdp, I get this: Cannot resolve alias 'cdp' because it refers to term 'cd 'C:\Users\ec\Documents\Visual Studio 2010\Projects'', which is not recognized as a cmdlet, function, operable program, or script file. Verify the term and try again. At line:1 char:4 + cdp <<<<  + CatergoryInfo   : ObjectNotFound (dsp:String) [], CommandNotFoundException  + FullyQualifiedErrorId   : AliasNotResolvedException I am guessing that this is trivially easy. So I apologize in advance if that is the case. I have googled and googled and have also read through Windows PowerShell Cookbook.

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  • So…is it a Seek or a Scan?

    - by Paul White
    You’re probably most familiar with the terms ‘Seek’ and ‘Scan’ from the graphical plans produced by SQL Server Management Studio (SSMS).  The image to the left shows the most common ones, with the three types of scan at the top, followed by four types of seek.  You might look to the SSMS tool-tip descriptions to explain the differences between them: Not hugely helpful are they?  Both mention scans and ranges (nothing about seeks) and the Index Seek description implies that it will not scan the index entirely (which isn’t necessarily true). Recall also yesterday’s post where we saw two Clustered Index Seek operations doing very different things.  The first Seek performed 63 single-row seeking operations; and the second performed a ‘Range Scan’ (more on those later in this post).  I hope you agree that those were two very different operations, and perhaps you are wondering why there aren’t different graphical plan icons for Range Scans and Seeks?  I have often wondered about that, and the first person to mention it after yesterday’s post was Erin Stellato (twitter | blog): Before we go on to make sense of all this, let’s look at another example of how SQL Server confusingly mixes the terms ‘Scan’ and ‘Seek’ in different contexts.  The diagram below shows a very simple heap table with two columns, one of which is the non-clustered Primary Key, and the other has a non-unique non-clustered index defined on it.  The right hand side of the diagram shows a simple query, it’s associated query plan, and a couple of extracts from the SSMS tool-tip and Properties windows. Notice the ‘scan direction’ entry in the Properties window snippet.  Is this a seek or a scan?  The different references to Scans and Seeks are even more pronounced in the XML plan output that the graphical plan is based on.  This fragment is what lies behind the single Index Seek icon shown above: You’ll find the same confusing references to Seeks and Scans throughout the product and its documentation. Making Sense of Seeks Let’s forget all about scans for a moment, and think purely about seeks.  Loosely speaking, a seek is the process of navigating an index B-tree to find a particular index record, most often at the leaf level.  A seek starts at the root and navigates down through the levels of the index to find the point of interest: Singleton Lookups The simplest sort of seek predicate performs this traversal to find (at most) a single record.  This is the case when we search for a single value using a unique index and an equality predicate.  It should be readily apparent that this type of search will either find one record, or none at all.  This operation is known as a singleton lookup.  Given the example table from before, the following query is an example of a singleton lookup seek: Sadly, there’s nothing in the graphical plan or XML output to show that this is a singleton lookup – you have to infer it from the fact that this is a single-value equality seek on a unique index.  The other common examples of a singleton lookup are bookmark lookups – both the RID and Key Lookup forms are singleton lookups (an RID lookup finds a single record in a heap from the unique row locator, and a Key Lookup does much the same thing on a clustered table).  If you happen to run your query with STATISTICS IO ON, you will notice that ‘Scan Count’ is always zero for a singleton lookup. Range Scans The other type of seek predicate is a ‘seek plus range scan’, which I will refer to simply as a range scan.  The seek operation makes an initial descent into the index structure to find the first leaf row that qualifies, and then performs a range scan (either backwards or forwards in the index) until it reaches the end of the scan range. The ability of a range scan to proceed in either direction comes about because index pages at the same level are connected by a doubly-linked list – each page has a pointer to the previous page (in logical key order) as well as a pointer to the following page.  The doubly-linked list is represented by the green and red dotted arrows in the index diagram presented earlier.  One subtle (but important) point is that the notion of a ‘forward’ or ‘backward’ scan applies to the logical key order defined when the index was built.  In the present case, the non-clustered primary key index was created as follows: CREATE TABLE dbo.Example ( key_col INTEGER NOT NULL, data INTEGER NOT NULL, CONSTRAINT [PK dbo.Example key_col] PRIMARY KEY NONCLUSTERED (key_col ASC) ) ; Notice that the primary key index specifies an ascending sort order for the single key column.  This means that a forward scan of the index will retrieve keys in ascending order, while a backward scan would retrieve keys in descending key order.  If the index had been created instead on key_col DESC, a forward scan would retrieve keys in descending order, and a backward scan would return keys in ascending order. A range scan seek predicate may have a Start condition, an End condition, or both.  Where one is missing, the scan starts (or ends) at one extreme end of the index, depending on the scan direction.  Some examples might help clarify that: the following diagram shows four queries, each of which performs a single seek against a column holding every integer from 1 to 100 inclusive.  The results from each query are shown in the blue columns, and relevant attributes from the Properties window appear on the right: Query 1 specifies that all key_col values less than 5 should be returned in ascending order.  The query plan achieves this by seeking to the start of the index leaf (there is no explicit starting value) and scanning forward until the End condition (key_col < 5) is no longer satisfied (SQL Server knows it can stop looking as soon as it finds a key_col value that isn’t less than 5 because all later index entries are guaranteed to sort higher). Query 2 asks for key_col values greater than 95, in descending order.  SQL Server returns these results by seeking to the end of the index, and scanning backwards (in descending key order) until it comes across a row that isn’t greater than 95.  Sharp-eyed readers may notice that the end-of-scan condition is shown as a Start range value.  This is a bug in the XML show plan which bubbles up to the Properties window – when a backward scan is performed, the roles of the Start and End values are reversed, but the plan does not reflect that.  Oh well. Query 3 looks for key_col values that are greater than or equal to 10, and less than 15, in ascending order.  This time, SQL Server seeks to the first index record that matches the Start condition (key_col >= 10) and then scans forward through the leaf pages until the End condition (key_col < 15) is no longer met. Query 4 performs much the same sort of operation as Query 3, but requests the output in descending order.  Again, we have to mentally reverse the Start and End conditions because of the bug, but otherwise the process is the same as always: SQL Server finds the highest-sorting record that meets the condition ‘key_col < 25’ and scans backward until ‘key_col >= 20’ is no longer true. One final point to note: seek operations always have the Ordered: True attribute.  This means that the operator always produces rows in a sorted order, either ascending or descending depending on how the index was defined, and whether the scan part of the operation is forward or backward.  You cannot rely on this sort order in your queries of course (you must always specify an ORDER BY clause if order is important) but SQL Server can make use of the sort order internally.  In the four queries above, the query optimizer was able to avoid an explicit Sort operator to honour the ORDER BY clause, for example. Multiple Seek Predicates As we saw yesterday, a single index seek plan operator can contain one or more seek predicates.  These seek predicates can either be all singleton seeks or all range scans – SQL Server does not mix them.  For example, you might expect the following query to contain two seek predicates, a singleton seek to find the single record in the unique index where key_col = 10, and a range scan to find the key_col values between 15 and 20: SELECT key_col FROM dbo.Example WHERE key_col = 10 OR key_col BETWEEN 15 AND 20 ORDER BY key_col ASC ; In fact, SQL Server transforms the singleton seek (key_col = 10) to the equivalent range scan, Start:[key_col >= 10], End:[key_col <= 10].  This allows both range scans to be evaluated by a single seek operator.  To be clear, this query results in two range scans: one from 10 to 10, and one from 15 to 20. Final Thoughts That’s it for today – tomorrow we’ll look at monitoring singleton lookups and range scans, and I’ll show you a seek on a heap table. Yes, a seek.  On a heap.  Not an index! If you would like to run the queries in this post for yourself, there’s a script below.  Thanks for reading! IF OBJECT_ID(N'dbo.Example', N'U') IS NOT NULL BEGIN DROP TABLE dbo.Example; END ; -- Test table is a heap -- Non-clustered primary key on 'key_col' CREATE TABLE dbo.Example ( key_col INTEGER NOT NULL, data INTEGER NOT NULL, CONSTRAINT [PK dbo.Example key_col] PRIMARY KEY NONCLUSTERED (key_col) ) ; -- Non-unique non-clustered index on the 'data' column CREATE NONCLUSTERED INDEX [IX dbo.Example data] ON dbo.Example (data) ; -- Add 100 rows INSERT dbo.Example WITH (TABLOCKX) ( key_col, data ) SELECT key_col = V.number, data = V.number FROM master.dbo.spt_values AS V WHERE V.[type] = N'P' AND V.number BETWEEN 1 AND 100 ; -- ================ -- Singleton lookup -- ================ ; -- Single value equality seek in a unique index -- Scan count = 0 when STATISTIS IO is ON -- Check the XML SHOWPLAN SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col = 32 ; -- =========== -- Range Scans -- =========== ; -- Query 1 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col <= 5 ORDER BY E.key_col ASC ; -- Query 2 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col > 95 ORDER BY E.key_col DESC ; -- Query 3 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col >= 10 AND E.key_col < 15 ORDER BY E.key_col ASC ; -- Query 4 SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col >= 20 AND E.key_col < 25 ORDER BY E.key_col DESC ; -- Final query (singleton + range = 2 range scans) SELECT E.key_col FROM dbo.Example AS E WHERE E.key_col = 10 OR E.key_col BETWEEN 15 AND 20 ORDER BY E.key_col ASC ; -- === TIDY UP === DROP TABLE dbo.Example; © 2011 Paul White email: [email protected] twitter: @SQL_Kiwi

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