logical domains - Page 165

SQL SERVER – Beginning of SQL Server Architecture – Terminology – Guest Post

- by pinaldave

SQL Server Architecture is a very deep subject. Covering it in a single post is an almost impossible task. However, this subject is very popular topic among beginners and advanced users. I have requested my friend Anil Kumar who is expert in SQL Domain to help me write a simple post about Beginning SQL Server Architecture. As stated earlier this subject is very deep subject and in this first article series he has covered basic terminologies. In future article he will explore the subject further down. Anil Kumar Yadav is Trainer, SQL Domain, Koenig Solutions. Koenig is a premier IT training firm that provides several IT certifications, such as Oracle 11g, Server+, RHCA, SQL Server Training, Prince2 Foundation etc. In this Article we will discuss about MS SQL Server architecture. The major components of SQL Server are: Relational Engine Storage Engine SQL OS Now we will discuss and understand each one of them. 1) Relational Engine: Also called as the query processor, Relational Engine includes the components of SQL Server that determine what your query exactly needs to do and the best way to do it. It manages the execution of queries as it requests data from the storage engine and processes the results returned. Different Tasks of Relational Engine: Query Processing Memory Management Thread and Task Management Buffer Management Distributed Query Processing 2) Storage Engine: Storage Engine is responsible for storage and retrieval of the data on to the storage system (Disk, SAN etc.). to understand more, let’s focus on the following diagram. When we talk about any database in SQL server, there are 2 types of files that are created at the disk level – Data file and Log file. Data file physically stores the data in data pages. Log files that are also known as write ahead logs, are used for storing transactions performed on the database. Let’s understand data file and log file in more details: Data File: Data File stores data in the form of Data Page (8KB) and these data pages are logically organized in extents. Extents: Extents are logical units in the database. They are a combination of 8 data pages i.e. 64 KB forms an extent. Extents can be of two types, Mixed and Uniform. Mixed extents hold different types of pages like index, System, Object data etc. On the other hand, Uniform extents are dedicated to only one type. Pages: As we should know what type of data pages can be stored in SQL Server, below mentioned are some of them: Data Page: It holds the data entered by the user but not the data which is of type text, ntext, nvarchar(max), varchar(max), varbinary(max), image and xml data. Index: It stores the index entries. Text/Image: It stores LOB ( Large Object data) like text, ntext, varchar(max), nvarchar(max), varbinary(max), image and xml data. GAM & SGAM (Global Allocation Map & Shared Global Allocation Map): They are used for saving information related to the allocation of extents. PFS (Page Free Space): Information related to page allocation and unused space available on pages. IAM (Index Allocation Map): Information pertaining to extents that are used by a table or index per allocation unit. BCM (Bulk Changed Map): Keeps information about the extents changed in a Bulk Operation. DCM (Differential Change Map): This is the information of extents that have modified since the last BACKUP DATABASE statement as per allocation unit. Log File: It also known as write ahead log. It stores modification to the database (DML and DDL). Sufficient information is logged to be able to: Roll back transactions if requested Recover the database in case of failure Write Ahead Logging is used to create log entries Transaction logs are written in chronological order in a circular way Truncation policy for logs is based on the recovery model SQL OS: This lies between the host machine (Windows OS) and SQL Server. All the activities performed on database engine are taken care of by SQL OS. It is a highly configurable operating system with powerful API (application programming interface), enabling automatic locality and advanced parallelism. SQL OS provides various operating system services, such as memory management deals with buffer pool, log buffer and deadlock detection using the blocking and locking structure. Other services include exception handling, hosting for external components like Common Language Runtime, CLR etc. I guess this brief article gives you an idea about the various terminologies used related to SQL Server Architecture. In future articles we will explore them further. Guest Author The author of the article is Anil Kumar Yadav is Trainer, SQL Domain, Koenig Solutions. Koenig is a premier IT training firm that provides several IT certifications, such as Oracle 11g, Server+, RHCA, SQL Server Training, Prince2 Foundation etc. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Security, SQL Server, SQL Tips and Tricks, SQL Training, T SQL, Technology

Read the article

RK4 Bouncing a Ball

- by Jonathan Dickinson

I am trying to wrap my head around RK4. I decided to do the most basic 'ball with gravity that bounces' simulation. I have implemented the following integrator given Glenn Fiedler's tutorial: /// <summary> /// Represents physics state. /// </summary> public struct State { // Also used internally as derivative. // S: Position // D: Velocity. /// <summary> /// Gets or sets the Position. /// </summary> public Vector2 X; // S: Position // D: Acceleration. /// <summary> /// Gets or sets the Velocity. /// </summary> public Vector2 V; } /// <summary> /// Calculates the force given the specified state. /// </summary> /// <param name="state">The state.</param> /// <param name="t">The time.</param> /// <param name="acceleration">The value that should be updated with the acceleration.</param> public delegate void EulerIntegrator(ref State state, float t, ref Vector2 acceleration); /// <summary> /// Represents the RK4 Integrator. /// </summary> public static class RK4 { private const float OneSixth = 1.0f / 6.0f; private static void Evaluate(EulerIntegrator integrator, ref State initial, float t, float dt, ref State derivative, ref State output) { var state = new State(); // These are a premature optimization. I like premature optimization. // So let's not concentrate on that. state.X.X = initial.X.X + derivative.X.X * dt; state.X.Y = initial.X.Y + derivative.X.Y * dt; state.V.X = initial.V.X + derivative.V.X * dt; state.V.Y = initial.V.Y + derivative.V.Y * dt; output = new State(); output.X.X = state.V.X; output.X.Y = state.V.Y; integrator(ref state, t + dt, ref output.V); } /// <summary> /// Performs RK4 integration over the specified state. /// </summary> /// <param name="eulerIntegrator">The euler integrator.</param> /// <param name="state">The state.</param> /// <param name="t">The t.</param> /// <param name="dt">The dt.</param> public static void Integrate(EulerIntegrator eulerIntegrator, ref State state, float t, float dt) { var a = new State(); var b = new State(); var c = new State(); var d = new State(); Evaluate(eulerIntegrator, ref state, t, 0.0f, ref a, ref a); Evaluate(eulerIntegrator, ref state, t + dt * 0.5f, dt * 0.5f, ref a, ref b); Evaluate(eulerIntegrator, ref state, t + dt * 0.5f, dt * 0.5f, ref b, ref c); Evaluate(eulerIntegrator, ref state, t + dt, dt, ref c, ref d); a.X.X = OneSixth * (a.X.X + 2.0f * (b.X.X + c.X.X) + d.X.X); a.X.Y = OneSixth * (a.X.Y + 2.0f * (b.X.Y + c.X.Y) + d.X.Y); a.V.X = OneSixth * (a.V.X + 2.0f * (b.V.X + c.V.X) + d.V.X); a.V.Y = OneSixth * (a.V.Y + 2.0f * (b.V.Y + c.V.Y) + d.V.Y); state.X.X = state.X.X + a.X.X * dt; state.X.Y = state.X.Y + a.X.Y * dt; state.V.X = state.V.X + a.V.X * dt; state.V.Y = state.V.Y + a.V.Y * dt; } } After reading over the tutorial I noticed a few things that just seemed 'out' to me. Notably how the entire simulation revolves around t at 0 and state at 0 - considering that we are working out a curve over the duration it seems logical that RK4 wouldn't be able to handle this simple scenario. Never-the-less I forged on and wrote a very simple Euler integrator: static void Integrator(ref State state, float t, ref Vector2 acceleration) { if (state.X.Y > 100 && state.V.Y > 0) { // Bounce vertically. acceleration.Y = -state.V.Y * t; } else { acceleration.Y = 9.8f; } } I then ran the code against a simple fixed-time step loop and this is what I got: 0.05 0.20 0.44 0.78 1.23 1.76 ... 74.53 78.40 82.37 86.44 90.60 94.86 99.23 103.05 105.45 106.94 107.86 108.42 108.76 108.96 109.08 109.15 109.19 109.21 109.23 109.23 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 109.24 ... As I said, I was expecting it to break - however I am unsure of how to fix it. I am currently looking into keeping the previous state and time, and working from that - although at the same time I assume that will defeat the purpose of RK4. How would I get this simulation to print the expected results?

Read the article

Guest Post: Christian Finn: Is Facebook About to Become a Victim of its Own Success?

- by Michael Snow

12.00 Print 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Cambria","serif"; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Cambria; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin;} Since we have a number of new members of the WebCenter Evangelist team - I thought it would be appropriate to close the week with the newest hire and leader of the global WebCenter Evangelists, Christian Finn, who has just joined the Red team after many years with the small technology company up in Redmond, WA. He gave an intro to himself in an earlier post this morning but his post below is a great example of how customer engagement takes on a life of its own in our global online connected and social digital ecosystem. Is Facebook About to Become a Victim of its Own Success? What if I told you that your brand could advertise so successfully, you wouldn’t have to pay for the ads? A recent campaign by Ford Motor Company for the Ford Focus featuring Doug the spokespuppet (I am not making this up) did just that—and it raises some interesting issues for marketers and social media alike in the brave new world of customer engagement that is the Social Web. Allow me to elaborate. An article in the Wall Street Journal last week—“Big Brands Like Facebook, But They Don’t Like to Pay” tells the story of Ford’s recently concluded online campaign for the 2012 Ford Focus. (Ford, by the way, under the leadership of people such as Scott Monty, has been a pioneer of effective social campaigns.) The centerpiece of the campaign was the aforementioned Doug, who appeared as a character on Facebook in videos and via chat. (If you are not familiar with Doug, you can see him in action here, and read the WSJ story here.) You may be thinking puppet ads are a sign of Internet Bubble 2.0 and want to stop now, but bear with me. The Journal reported that Ford spent about $95M on its overall Ford Focus campaign, with TV accounting for over $60M of that spend. The Internet buy for the campaign was just over $10M, which included ad buys to drive traffic to Facebook for people to meet and ‘Like’ Doug and some amount on Facebook ads, too, to promote Doug and by extension, the Ford Focus. So far, a fairly straightforward consumer marketing story in the Internet Era. Yet here’s the curious thing: once Doug reached 10,000 fans on Facebook, Ford stopped paying for Facebook ads. Doug had gone viral with people sharing his videos with one another; once critical mass was reached there was no need to buy more ads on Facebook. Doug went on to be Liked by over 43,000 people, and 61% of his fans said they would be more likely to consider buying a Focus. According to the article, Ford says Focus sales are up this year—and increasing sales is every marketer’s goal. And so in effect, Ford found its Facebook campaign so successful that it could stop paying for it, instead letting its target consumers communicate its messages for fun—and for free. Not only did they get a 3X increase in fans beyond their paid campaign, they had thousands of customers sharing their messages in video form for months. Since free advertising is the Holy Grail of marketing both old and new-- and it appears social networks have an advantage in generating that buzz—it seems reasonable to ask: what would happen to brands’ advertising strategies—and the media they use to engage customers, if this success were repeated at scale? It seems logical to conclude that, at least initially, more ad dollars would be spent with social networks like Facebook as brands attempt to replicate Ford’s success. Certainly Facebook ad revenues are on the rise—eMarketer expects Facebook’s ad revenues to quintuple by 2012 compared with 2009 levels, to nearly 2.9B. That’s bad news for TV and the already battered print media and good news for Facebook. But perhaps not so over the longer run. With TV buys, you have to keep paying to generate impressions. If Doug the spokespuppet is any guide, however, that may not be true for social media campaigns. After an initial outlay, if a social campaign takes off, the audience will generate more impressions on its own. Thus a social medium like Facebook could be the victim of its own success when it comes to ad revenue. It may be there is an inherent limiting factor in the ad spend they can capture, as exemplified by Ford’s experience with Dough and the Focus. And brands may spend much less overall on advertising, with as good or better results, than they ever have in the past. How will these trends evolve? Can brands create social campaigns that repeat Ford’s formula for the Focus with effective results? Can social networks find ways to capture more spend and overcome their potential tendency to make further spend unnecessary? And will consumers become tired and insulated from social campaigns, much as they have to traditional advertising channels? These are the questions CMOs and Facebook execs alike will be asking themselves in the brave new world of customer engagement. As always, your thoughts and comments are most welcome.

Read the article

SQL Server service accounts and SPNs

- by simonsabin

Service Principal Names (SPNs) are a must for kerberos authentication which is a must when using sharepoint, reporting services and sql server where you access one server that then needs to access another resource, this is called the double hop. The reason this is a complex problem is that the second hop has to be done with impersonation/delegation. For this to work there needs to be a way for the security system to make sure that the service in the middle is allowed to impersonate you, after all you are not giving the service your password. To do this you need to be using kerberos. The following is my simple interpretation of how kerberos works. I find the Kerberos documentation rediculously complex so the following might be sligthly wrong but I think its close enough. Keberos works on a ticketing system, the prinicipal is that you get a security token from AD and then you can pass that to the service in the middle which can then use that token to impersonate you. For that to work AD has to be able to identify who is allowed to use the token, in this case the service account.But how do you as a client know what service account the service in the middle is configured with. The answer is SPNs. The SPN is the mapping between your logical connection to the service account. One type of SPN is for the DNS name for the server and the port. i.e. MySQL.mydomain.com and 1433. You can see how this maps to SQL Server on that server, but how does it map to the account. Well it can be done in two ways, either you can have a mapping defined in AD or AD can use a default mapping (this is something I didn't know about). To map the SPN in AD then you have to add the SPN to the user account, this is documented in the first link below either directly or using a tool called SetSPN. You might say that is complex, well it is and thats why SQL Server tries to do it for you, at start up it tries to connect to AD and set the SPN on the account it is running as, clearly that can only happen IF SQL is running as a domain account AND importantly it has permission to do so. By default a normal domain user account doesn't have the correct permission, and is why so many people have this problem. If the account is a domain admin then it will have permission, but non of us run SQL using domain admin accounts do we. You might also note that the SPN contains the port number (this isn't a requirement now in sql 2008 but I won't go into that), so if you set it manually and you are using dynamic ports (the default for a named instance) what do you do, well every time the port changes you need to change the SPN allocated to the account. Thats why its advised to let SQL Server register the SPN itself. You may also have thought, well what happens if I change my service account, won't that lead to two accounts with the same SPN. Possibly. Having two accounts with the same SPN is definitely a problem. Why? Well because if there are two accounts Kerberos can't identify the exact account that the service is running as, it could be either account, and so your security falls back to NTLM. SETSPN is useful for finding duplicate SPNs Reading this you will probably be thinking Oh my goodness this is really difficult. It is however I've found today in investigating something else that there is an easy option. Use Network Service as your service account. Network Service is a special account and is tied to the computer. It appears that Network Service has the update rights to AD to set an SPN mapping for the computer account. This then allows the SPN mapping to work. I believe this also works for the local system account. To get all the SPNs in your AD run the following, it could be a large file, so you might want to restrict it to a specific OU, or CN ldifde -d "DC=<domain>" -l servicePrincipalName -F spn.txt You will read in the links below that you need SQL to register the SPN this is done how to use Kerberos authenticaiton in SQL Server - http://support.microsoft.com/kb/319723 Using Kerberos with SQL Server - http://blogs.msdn.com/sql_protocols/archive/2005/10/12/479871.aspx Understanding Kerberos and NTLM authentication in SQL Server Connections - http://blogs.msdn.com/sql_protocols/archive/2006/12/02/understanding-kerberos-and-ntlm-authentication-in-sql-server-connections.aspx Summary The only reason I personally know to use a domain account is when you can't get kerberos to work and you want to do BULK INSERT or other network service that requires access to a a remote server. In this case you have to resort to using SQL authentication and the SQL Server uses its service account to access the remote service, and thus you need a domain account. You migth need this if using some forms of replication. I've always found Kerberos awkward to setup and so fallen back to this domain account approach. So in summary to get Kerberos to work try using the network service or local system accounts. For a great post from the Adam Saxton of the SQL Server support team go to http://blogs.msdn.com/psssql/archive/2010/03/09/what-spn-do-i-use-and-how-does-it-get-there.aspx

Read the article

SQLAuthority News – Why VoIP Service Providers Should Think About NuoDB’s Geo Distribution

- by Pinal Dave

You can always tell when someone’s showing off their cool, cutting edge comms technology. They tend to raise their voice a lot. Back in the day they’d announce their gadget leadership to the rest of the herd by shouting into their cellphone. Usually the message was no more urgent than “Hi, I’m on my cellphone!” Now the same types will loudly name-drop a different technology to the rest of the airport lounge. “I’m leveraging the wifi,” a fellow passenger bellowed, the other day, as we filtered through the departure gate. Nobody needed to know that, but the subtext was “look at me everybody”. You can tell the really advanced mobile user – they tend to whisper. Their handset has a microphone (how cool is that!) and they know how to use it. Sometimes these shouty public broadcasters aren’t even connected anyway because the database for their Voice over IP (VoIP) platform can’t cope. This will happen if they are using a traditional SQL model to try and cope with a phone network which has far flung offices and hundreds of mobile employees. That, like shouting into your phone, is just wrong on so many levels. What VoIP needs now is a single, logical database across multiple servers in different geographies. It needs to be updated in real-time and automatically scaled out during times of peak demand. A VoIP system should scale up to handle increased traffic, but just as importantly is must then go back down in the off peak hours. Try this with a MySQL database. It can’t scale easily enough, so it will keep your developers busy. They’ll have spent many hours trying to knit the different databases together. Traditional relational databases can possibly achieve this, at a price. Mind you, you could extend baked bean cans and string to every point on the network and that would be no less elegant. That’s not really following engineering principles though is it? Having said that, most telcos and VoIP systems use a separate, independent solution for each office location, which they link together – loosely. The more office locations, the more complex and expensive the solution becomes and so the more you spend on maintenance. Ideally, you’d have a fluid system that can automatically shift its shape as the need arises. That’s the point of software isn’t it – it adapts. Otherwise, we might as well return to the old days. A MySQL system isn’t exactly baked bean cans attached by string, but it’s closer in spirit to the old many teethed mechanical beast that was employed in the first type of automated switchboard. NuoBD’s NewSQL is designed to be a single database that works across multiple servers, which can scale easily, and scale on demand. That’s one system that gives high connectivity but no latency, complexity or maintenance issues. MySQL works in some circumstances, but a period of growth isn’t one of them. So as a company moves forward, the MySQL database can’t keep pace. Data storage and data replication errors creep in. Soon the diaspora of offices becomes a problem. Your telephone system isn’t just distributed, it is literally all over the place. Though voice calls are often a software function, some of the old habits of telephony remain. When you call an engineer out, some of them will listen to what you’re asking for and announce that it cannot be done. This is what happens if you ask, say, database engineers familiar with Oracle or Microsoft to fulfill your wish for a low maintenance system built on a single, fluid, scalable database. No can do, they’d say. In fact, I heard one shouting something similar into his VoIP handset at the airport. “I can’t get on the network, Mac. I’m on MySQL.” You can download NuoDB from here. “NuoDB provides the ability to replicate data globally in real-time, which is not available with any other product offering,” states Weeks. “That alone is remarkable and it works. I’ve seen it. I’ve used it. I’ve tested it. The ability to deploy NuoDB removes a tremendous burden from our support and engineering teams.” Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: NuoDB

Read the article

Running a Silverlight application in the Google App Engine platform

- by rajbk

This post shows you how to host a Silverlight application in the Google App Engine (GAE) platform. You deploy and host your Silverlight application on Google’s infrastructure by creating a configuration file and uploading it along with your application files. I tested this by uploading an old demo of mine - the four stroke engine silverlight demo. It is currently being served by the GAE over here: http://fourstrokeengine.appspot.com/ The steps to run your Silverlight application in GAE are as follows: Account Creation Create an account at http://appengine.google.com/. You are allocated a free quota at signup. Select “Create an Application” Verify your account by SMS Create your application by clicking on “Create an Application” Pick an application identifier on the next screen. The identifier has to be unique. You will use this identifier when uploading your application. The application you create will by default be accessible at [applicationidentifier].appspot.com. You can also use custom domains if needed (refer to the docs). Save your application. Download SDK We will use the Windows Launcher for Google App Engine tool to upload our apps (it is possible to do the same through command line). This is a GUI for creating, running and deploying applications. The launcher lets you test the app locally before deploying it to the GAE. This tool is available in the Google App Engine SDK. The GUI is written in Python and therefore needs an installation of Python to run. Download and install the Python Binaries from here: http://www.python.org/download/ Download and install the Google App Engine SDK from here: http://code.google.com/appengine/downloads.html Run the GAE Launcher. Select Create New Application. On the next dialog, give your application a name (this must match the identifier we created earlier) For Parent Directory, point to the directory containing your Silverlight files. Change the port if you want to. The port is used by the GAE local web server. The server is started if you choose to run the application locally for testing purposes. Hit Save. Configure, Test and Upload As shown below, the files I am interested in uploading for my Silverlight demo app are The html page used to host the Silverlight control The xap file containing the compiled Silverlight application A favicon.ico file. We now create a configuration file for our application called app.yaml. The app.yaml file specifies how URL paths correspond to request handlers and static files. We edit the file by selecting our app in the GUI and clicking “Edit” The contents of file after editing is shown below (note that the contents of the file should be in plain text): application: fourstrokeengine version: 1 runtime: python api_version: 1 handlers: - url: / static_files: Default.html upload: Default.html - url: /favicon.ico static_files: favicon.ico upload: favicon.ico - url: /FourStrokeEngine.xap static_files: FourStrokeEngine.xap upload: FourStrokeEngine.xap mime_type: application/x-silverlight-app - url: /.* static_files: Default.html upload: Default.html We have listed URL patterns for our files, specified them as static files and specified a mime type for our xap file. The wild card URL at the end will match all URLs that are not found to our default page (you would normally include a html file that displays a 404 message). To understand more about app.yaml, refer to this page. Save the file. Run the application locally by selecting “Browse” in the GUI. A web server listening on the port you specified is started (8080 in my case). The app is loaded in your default web browser pointing to http://localhost:8080/. Make sure the application works as expected. We are now ready to deploy. Click the “Deploy” icon. You will be prompted for your username and password. Hit OK. The files will get uploaded and you should get a dialog telling you to “close the window”. We are done uploading our Silverlight application. Go to http://appengine.google.com/ and launch the application by clicking on the link in the “Current Version” column. You should be taken to a URL which points to your application running in Google’s infrastructure : http://fourstrokeengine.appspot.com/. We are done deploying our application! Clicking on the link in the Application column will take you to the Admin console where you can see stats related to system usage. To learn more about the Google Application Engine, go here: http://code.google.com/appengine/docs/whatisgoogleappengine.html

Read the article

Oracle Database 12c: Oracle Multitenant Option

- by hamsun

1. Why ? 2. What is it ? 3. How ? 1. Why ? The main idea of the 'grid' is to share resources, to make better use of storage, CPU and memory. If a database administrator wishes to implement this idea, he or she must consolidate many databases to one database. One of the concerns of running many applications together in one database is: ‚what will happen, if one of the applications must be restored because of a human error?‘ Tablespace point in time recovery can be used for this purpose, but there are a few prerequisites. Most importantly the tablespaces are strictly separated for each application. Another reason for creating separated databases is security: each customer has his own database. Therefore, there is often a proliferation of smaller databases. Each of them must be maintained, upgraded, each allocates virtual memory and runs background processes thereby wasting resources. Oracle 12c offers another possibility for virtualization, providing isolation at the database level: the multitenant container database holding pluggable databases. 2. What ? Pluggable databases are logical units inside a multitenant container database, which consists of one multitenant container database and up to 252 pluggable databases. The SGA is shared as are the background processes. The multitenant container database holds metadata information common for pluggable databases inside the System and the Sysaux tablespace, and there is just one Undo tablespace. The pluggable databases have smaller System and Sysaux tablespaces, containing just their 'personal' metadata. New data dictionary views will make the information available either on pdb (dba_views) or container level (cdb_views). There are local users, which are known in specific pluggable databases and common users known in all containers. Pluggable databases can be easily plugged to another multitenant container database and converted from a non-CDB. They can undergo point in time recovery. 3. How ? Creating a multitenant container database can be done using the database configuration assistant: There you find the new option: Create as Container Database. If you prefer ‚hand made‘ databases you can execute the command from a instance in nomount state: CREATE DATABASE cdb1 ENABLE PLUGGABLE DATABASE …. And of course this can also be achieved through Enterprise Manager Cloud. A freshly created multitenant container database consists of two containers: the root container as the 'rack' and a seed container, a template for future pluggable databases. There are 4 ways to create other pluggable databases: 1. Create an empty pdb from seed 2. Plug in a non-CDB 3. Move a pdb from another pdb 4. Copy a pdb from another pdb We will discuss option2: how to plug in a non_CDB into a multitenant container database. Three different methods are available : 1. Create an empty pdb and use Datapump in traditional export/import mode or with Transportable Tablespace or Database mode. This method is suitable for pre 12c databases. 2. Create an empty pdb and use GoldenGate replication. When the pdb catches up with the non-CDB, you fail over to the pdb. 3. Databases of Version 12c or higher can be plugged in with the help of the new dbms_pdb Package. This is a demonstration for method 3: Step1: Connect to the non-CDB to be plugged in and create an xml File with description of the database. The xml file is written to $ORACLE_HOME/dbs per default and contains mainly information about the datafiles. Step 2: Check if the non-CDB is pluggable in the multitenant container database: Step 3: Create the pluggable database, connected to the Multitenant container database. With nocopy option the files will be reused, but the tempfile is created anew: A service is created and registered automatically with the listener: Step 4: Delete unnecessary metadata from PDB SYSTEM tablespace: To connect to newly created pdb, edit tnsnames.ora and add entry for new pdb. Connect to plugged-in non_CDB and clean up Data Dictionary to remove entries now maintained in multitenant container database. As all kept objects have to be recompiled it will take a few minutes. Step 5: The plugged-in database will be automatically synchronised by creating common users and roles when opened the first time in read write mode. Step 6: Verify tablespaces and users: There is only one local tablespace (users) and one local user (scott) in the plugged-in non_CDB pdb_orcl. This method of creating plugged_in non_CDB from is fast and easy for 12c databases. The method for deplugging a pluggable database from a CDB is to create a new non_CDB and use the the new full transportable feature of Datapump and drop the pluggable database. About the Author: Gerlinde has been working for Oracle University Germany as one of our Principal Instructors for over 14 years. She started with Oracle 7 and became an Oracle Certified Master for Oracle 10g and 11c. She is a specialist in Database Core Technologies, with profound knowledge in Backup & Recovery, Performance Tuning for DBAs and Application Developers, Datawarehouse Administration, Data Guard and Real Application Clusters.

Read the article

Partition Wise Joins

- by jean-pierre.dijcks

Some say they are the holy grail of parallel computing and PWJ is the basis for a shared nothing system and the only join method that is available on a shared nothing system (yes this is oversimplified!). The magic in Oracle is of course that is one of many ways to join data. And yes, this is the old flexibility vs. simplicity discussion all over, so I won't go there... the point is that what you must do in a shared nothing system, you can do in Oracle with the same speed and methods. The Theory A partition wise join is a join between (for simplicity) two tables that are partitioned on the same column with the same partitioning scheme. In shared nothing this is effectively hard partitioning locating data on a specific node / storage combo. In Oracle is is logical partitioning. If you now join the two tables on that partitioned column you can break up the join in smaller joins exactly along the partitions in the data. Since they are partitioned (grouped) into the same buckets, all values required to do the join live in the equivalent bucket on either sides. No need to talk to anyone else, no need to redistribute data to anyone else... in short, the optimal join method for parallel processing of two large data sets. PWJ's in Oracle Since we do not hard partition the data across nodes in Oracle we use the Partitioning option to the database to create the buckets, then set the Degree of Parallelism (or run Auto DOP - see here) and get our PWJs. The main questions always asked are: How many partitions should I create? What should my DOP be? In a shared nothing system the answer is of course, as many partitions as there are nodes which will be your DOP. In Oracle we do want you to look at the workload and concurrency, and once you know that to understand the following rules of thumb. Within Oracle we have more ways of joining of data, so it is important to understand some of the PWJ ideas and what it means if you have an uneven distribution across processes. Assume we have a simple scenario where we partition the data on a hash key resulting in 4 hash partitions (H1 -H4). We have 2 parallel processes that have been tasked with reading these partitions (P1 - P2). The work is evenly divided assuming the partitions are the same size and we can scan this in time t1 as shown below. Now assume that we have changed the system and have a 5th partition but still have our 2 workers P1 and P2. The time it takes is actually 50% more assuming the 5th partition has the same size as the original H1 - H4 partitions. In other words to scan these 5 partitions, the time t2 it takes is not 1/5th more expensive, it is a lot more expensive and some other join plans may now start to look exciting to the optimizer. Just to post the disclaimer, it is not as simple as I state it here, but you get the idea on how much more expensive this plan may now look... Based on this little example there are a few rules of thumb to follow to get the partition wise joins. First, choose a DOP that is a factor of two (2). So always choose something like 2, 4, 8, 16, 32 and so on... Second, choose a number of partitions that is larger or equal to 2* DOP. Third, make sure the number of partitions is divisible through 2 without orphans. This is also known as an even number... Fourth, choose a stable partition count strategy, which is typically hash, which can be a sub partitioning strategy rather than the main strategy (range - hash is a popular one). Fifth, make sure you do this on the join key between the two large tables you want to join (and this should be the obvious one...). Translating this into an example: DOP = 8 (determined based on concurrency or by using Auto DOP with a cap due to concurrency) says that the number of partitions >= 16. Number of hash (sub) partitions = 32, which gives each process four partitions to work on. This number is somewhat arbitrary and depends on your data and system. In this case my main reasoning is that if you get more room on the box you can easily move the DOP for the query to 16 without repartitioning... and of course it makes for no leftovers on the table... And yes, we recommend up-to-date statistics. And before you start complaining, do read this post on a cool way to do stats in 11.

Read the article

Connection Pooling is Busted

- by MightyZot

A few weeks ago we started getting complaints about performance in an application that has performed very well for many years. The application is a n-tier application that uses ADODB with the SQLOLEDB provider to talk to a SQL Server database. Our object model is written in such a way that each public method validates security before performing requested actions, so there is a significant number of queries executed to get information about file cabinets, retrieve images, create workflows, etc. (PaperWise is a document management and workflow system.) A common factor for these customers is that they have remote offices connected via MPLS networks. Naturally, the first thing we looked at was the query performance in SQL Profiler. All of the queries were executing within expected timeframes, most of them were so fast that the duration in SQL Profiler was zero. After getting nowhere with SQL Profiler, the situation was escalated to me. I decided to take a peek with Process Monitor. Procmon revealed some “gaps” in the TCP/IP traffic. There were notable delays between send and receive pairs. The send and receive pairs themselves were quite snappy, but quite often there was a notable delay between a receive and the next send. You might expect some delay because, presumably, the application is doing some thinking in-between the pairs. But, comparing the procmon data at the remote locations with the procmon data for workstations on the local network showed that the remote workstations were significantly delayed. Procmon also showed a high number of disconnects. Wireshark traces showed that connections to the database were taking between 75ms and 150ms. Not only that, but connections to a file share containing images were taking 2 seconds! So, I asked about a trust. Sure enough there was a trust between two domains and the file share was on the second domain. Joining a remote workstation to the domain hosting the share containing images alleviated the time delay in accessing the file share. Removing the trust had no affect on the connections to the database. Microsoft Network Monitor includes filters that parse TDS packets. TDS is the protocol that SQL Server uses to communicate. There is a certificate exchange and some SSL that occurs during authentication. All of this was evident in the network traffic. After staring at the network traffic for a while, and examining packets, I decided to call it a night. On the way home that night, something about the traffic kept nagging at me. Then it dawned on me…at the beginning of the dance of packets between the client and the server all was well. Connection pooling was working and I could see multiple queries getting executed on the same connection and ethereal port. After a particular query, connecting to two different servers, I noticed that ADODB and SQLOLEDB started making repeated connections to the database on different ethereal ports. SQL Server would execute a single query and respond on a port, then open a new port and execute the next query. Connection pooling appeared to be broken. The next morning I wrote a test to confirm my hypothesis. Turns out that the sequence causing the connection nastiness goes something like this: Make a connection to the database. Open a result set that returns enough records to require multiple roundtrips to the server. For each result, query for some other data in the database (this will open a new implicit connection.) Close the inner result set and repeat for every item in the original result set. Close the original connection. Provided that the first result set returns enough data to require multiple roundtrips to the server, ADODB and SQLOLEDB will start making new connections to the database for each query executed in the loop. Originally, I thought this might be due to Microsoft’s denial of service (ddos) attack protection. After turning those features off to no avail, I eventually thought to switch my queries to client-side cursors instead of server-side cursors. Server-side cursors are the default, by the way. Voila! After switching to client-side cursors, the disconnects were gone and the above sequence yielded two connections as expected. While the real problem is the amount of time it takes to make connections over these MPLS networks (100ms on average), switching to client-side cursors made the problem go away. Believe it or not, this is actually documented by Microsoft, and rather difficult to find. (At least it was while we were trying to troubleshoot the problem!) So, if you’re noticing performance issues on slower networks, or networks with slower switching, take a look at the traffic in a tool like Microsoft Network Monitor. If you notice a high number of disconnects, and you’re using fire-hose or server-side cursors, then try switching to client-side cursors and you may see the problem go away. Most likely, Microsoft believes this to be appropriate behavior, because ADODB can’t guarantee that all of the data has been retrieved when you execute the inner queries. I’m not convinced, though, because the problem remains even after replacing all of the implicit connections with explicit connections and closing those connections in-between each of the inner queries. In that case, there doesn’t seem to be a reason why ADODB can’t use a single connection from the connection pool to make the additional queries, bringing the total number of connections to two. Instead ADO appears to make an assumption about the state of the connection. I’ve reported the behavior to Microsoft and am awaiting to hear from the appropriate team, so that I can demonstrate the problem. Maybe they can explain to us why this is appropriate behavior. :)

Read the article

Simultaneously calling multiple methods on a WCF service from silverlight

- by ola karlsson

A while back I had to debug some performance issues in an existing Silverlight app, as the problem / solution was a bit obscure and finding info about it was quite tricky, I thought I’d share, maybe it can help the next person with this problem. The App On start, the app would do a number of calls to different methods on a WCF service, this to populate the UI with the necessary data. Recently one of those services had been changed and was now taking quite a bit longer than it used to. This was resulting in quite a long loading time for the whole UI, which was set up so it wouldn’t let the user interact with anything, until all the service calls had finished. First I broke out the longer running service call from the others, then removed the constraint that it had to be loaded for the UI in general to become responsive. I also added a loading indicator just on that area of the UI, thinking that the main UI would load while this particular section could keep loading independently. The Problem However this is where things started to get a bit strange. I found that even after these changes, the main UI wouldn’t activate until the long running call returned. So now, I did what I should have done to start with, I got Fiddler out and had a look at what was really happening. What I found was that, once the call to the long running service method was placed, all subsequent call were waiting for that one to return before executing. Not having really worked with WCF previously or knowing much about it in general, I was stumped… I knew of the issues where Silverlight is restricted by the browsers networking features in regards to number of simultaneous connections etc. However that just didn’t seem to be the issue here, you can clearly see in Fiddler that there’s numerous calls, but they’re just not returning. I thought of the problem maybe being in the WCF service, but the calls were really not that complicated and surely the service should be able to handle a lot more than what I was throwing at it! So I did what every developer does in this type of scenario, I hit the search engines. I did a whole bunch of searching on things like “multiple simultaneous WCF calls from Silverlight” and “Calling long running WCF services from Silverlight” etc. etc. This however, pretty much got me nowhere, I found a whole heap of resources on how to do WCF calls from Silverlight but most of them were very basic and of no use what so ever. The fog is clearing It wasn’t until I came across the term “ WCF blocking calls” and started incorporating that in my searches I started to get somewhere. Those searches quite quickly brought me to the following thread in the Silverlight forum “Long-running WCF call blocking subsequent calls” which discussed the exact problem I was facing and the best part, one of the guys there had the solution! The short answer is in the forum post and the guys answering, has also done a more extensive blog post about it called “Silverlight, WCF, and ASP.Net Configuration Gotchas” which covers it very well. So come on what’s the solution?! I heard you ask, unless you’ve already gone to the links and looked it up ;) The Solution Well, it turns out that the issue is founded in a mix of Silverlight, Asp.Net and WCF, basically if you’re doing multiple calls to a single WCF web-service and you have Asp.Net session state enabled, the calls will be executed sequentially by the service, hence any long running calls will block subsequent ones. So why is Asp.Net session state effecting us, we’re working in Silverlight, right? We'll as mentioned earlier, by default Silverlight uses the browsers networking stack when doing service calls, hence to the WCF service, the call looks like it might as well be coming from a normal Asp.Net. To get around this, we look to a feature introduced in Silverlight 3, namely the Client HTTP Stack. The Client HTTP Stack to the rescue By using the following syntax (for example in our App.xaml.cs, Application_Startup method) WebRequest.RegisterPrefix("http://", WebRequestCreator.ClientHttp); we can set our Silverlight application to use the Client HTTP Stack, which incidentally solves our problem! By using Silverlights own networking stack, rather than that of the browser, we get around the Asp.Net - WCF session state issue. The above code specifies that all calls to addresses starting with “http://” should go through the client stack, this can actually be set more granular and you can specify it to be used only for certain domains etc. Summary The actual solution is well covered in the forum and blog posts I link to above. This post is more about sharing my experience, hopefully helping to spread the word about this and maybe make it a bit easier for the next poor guy with this issue to find the solution. Until next time, Ola

Read the article

Developer Training – Difficult Questions and Alternative Perspective – Part 3

- by pinaldave

Developer Training - Importance and Significance - Part 1 Developer Training – Employee Morals and Ethics – Part 2 Developer Training – Difficult Questions and Alternative Perspective - Part 3 Developer Training – Various Options for Developer Training – Part 4 Developer Training – A Conclusive Summary- Part 5 Congratulations! You are now a fully trained developer! You spent hours in a classroom, watching webinars, and reading materials. You are now more educated and more prepared than ever before. Now what? Stay or Quit The simple answer is that you now have two options – stay where you are or move on to a new job. Even though you might now be smarter than you have ever felt before, this can still be a tough decision to make. You feel extra trained and ready for a promotion or a raise, but you and your employer might not see eye to eye on this issue. The logical conclusion is to go on a job hunt, but that might not be the most ethical thing to do. Click Image to Enlarge Manager’s Perspective Click Image to Enlarge Try to see the issue from your manager’s perspective. You feel that you have just spent a lot of time and energy getting trained, and you should be rewarded. But they have invested their time and energy in you. They might see the training as a way to help you complete the goals they require from you, or as a way to help you complete tasks that will ultimately end in a reward or promotion. Moral Compass As in most cases, honesty is the best policy. Be open with your manager about your expectations, and ask them to explain their goals. When there is open and honest communication, everyone can walk away happy. If you’re unable to discuss with your manager for one reason or another, just try to keep the company policy in mind and follow your own moral compass. If all else fails, and your company is unwilling to make allowances for your new value, offer to pay the company back for the training before moving on your way. Whether you stay at your old job or move on to a new one, you are still faced with the question of what you’re going to do with all your new knowledge. If you feel comfortable, offer to train others around you who are interested in the same subject. This can look very good on your resume, and if you are working in a team environment it is sure to help you in the long run! What Next? You can even offer to train other trainers at the company – managers, those above you, or even report back to your original trainer about how your education is helping you in the work place. Obviously this should be completely voluntary on the trainer’s part. Taking advice from a “newbie” may not be their favorite idea, but it could also show the company that you are open to expanding your horizons and being helpful to everyone around you. Last in Line for Opportunity Click Image to Enlarge At this time, let us address a subject related to training and what to do with it – what if you are always overlooked for training? This can as thorny a problem as receiving training in the first place. The best advice is to let your supervisors know that you are always open to training and very interested in certain topics. If you are consistently passed over, be patient. Your turn will probably come, but the company as a whole has to focus on other problems at the moment. If you feel that there are more personal issues at play, be sure to bring this up with your supervisor in a calm and professional manager so that everything can be worked out best for both parties. You, Yourself and Your Future! If all else fails, offer to pay for training yourself. Perhaps money problems are at the root of being passed over. Even if there are other reasons, offering to pay your own way shows your dedication and could work out well for you in the long run. Always remember – in life you have to go out and make your own way, you cannot always sit and wait for things to land in your lap. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Developer Training, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

Read the article

SQL SERVER – Fundamentals of Columnstore Index

- by pinaldave

There are two kind of storage in database. Row Store and Column Store. Row store does exactly as the name suggests – stores rows of data on a page – and column store stores all the data in a column on the same page. These columns are much easier to search – instead of a query searching all the data in an entire row whether the data is relevant or not, column store queries need only to search much lesser number of the columns. This means major increases in search speed and hard drive use. Additionally, the column store indexes are heavily compressed, which translates to even greater memory and faster searches. I am sure this looks very exciting and it does not mean that you convert every single index from row store to column store index. One has to understand the proper places where to use row store or column store indexes. Let us understand in this article what is the difference in Columnstore type of index. Column store indexes are run by Microsoft’s VertiPaq technology. However, all you really need to know is that this method of storing data is columns on a single page is much faster and more efficient. Creating a column store index is very easy, and you don’t have to learn new syntax to create them. You just need to specify the keyword “COLUMNSTORE” and enter the data as you normally would. Keep in mind that once you add a column store to a table, though, you cannot delete, insert or update the data – it is READ ONLY. However, since column store will be mainly used for data warehousing, this should not be a big problem. You can always use partitioning to avoid rebuilding the index. A columnstore index stores each column in a separate set of disk pages, rather than storing multiple rows per page as data traditionally has been stored. The difference between column store and row store approaches is illustrated below: In case of the row store indexes multiple pages will contain multiple rows of the columns spanning across multiple pages. In case of column store indexes multiple pages will contain multiple single columns. This will lead only the columns needed to solve a query will be fetched from disk. Additionally there is good chance that there will be redundant data in a single column which will further help to compress the data, this will have positive effect on buffer hit rate as most of the data will be in memory and due to same it will not need to be retrieved. Let us see small example of how columnstore index improves the performance of the query on a large table. As a first step let us create databaseset which is large enough to show performance impact of columnstore index. The time taken to create sample database may vary on different computer based on the resources. USE AdventureWorks GO -- Create New Table CREATE TABLE [dbo].[MySalesOrderDetail]( [SalesOrderID] [int] NOT NULL, [SalesOrderDetailID] [int] NOT NULL, [CarrierTrackingNumber] [nvarchar](25) NULL, [OrderQty] [smallint] NOT NULL, [ProductID] [int] NOT NULL, [SpecialOfferID] [int] NOT NULL, [UnitPrice] [money] NOT NULL, [UnitPriceDiscount] [money] NOT NULL, [LineTotal] [numeric](38, 6) NOT NULL, [rowguid] [uniqueidentifier] NOT NULL, [ModifiedDate] [datetime] NOT NULL ) ON [PRIMARY] GO -- Create clustered index CREATE CLUSTERED INDEX [CL_MySalesOrderDetail] ON [dbo].[MySalesOrderDetail] ( [SalesOrderDetailID]) GO -- Create Sample Data Table -- WARNING: This Query may run upto 2-10 minutes based on your systems resources INSERT INTO [dbo].[MySalesOrderDetail] SELECT S1.* FROM Sales.SalesOrderDetail S1 GO 100 Now let us do quick performance test. I have kept STATISTICS IO ON for measuring how much IO following queries take. In my test first I will run query which will use regular index. We will note the IO usage of the query. After that we will create columnstore index and will measure the IO of the same. -- Performance Test -- Comparing Regular Index with ColumnStore Index USE AdventureWorks GO SET STATISTICS IO ON GO -- Select Table with regular Index SELECT ProductID, SUM(UnitPrice) SumUnitPrice, AVG(UnitPrice) AvgUnitPrice, SUM(OrderQty) SumOrderQty, AVG(OrderQty) AvgOrderQty FROM [dbo].[MySalesOrderDetail] GROUP BY ProductID ORDER BY ProductID GO -- Table 'MySalesOrderDetail'. Scan count 1, logical reads 342261, physical reads 0, read-ahead reads 0. -- Create ColumnStore Index CREATE NONCLUSTERED COLUMNSTORE INDEX [IX_MySalesOrderDetail_ColumnStore] ON [MySalesOrderDetail] (UnitPrice, OrderQty, ProductID) GO -- Select Table with Columnstore Index SELECT ProductID, SUM(UnitPrice) SumUnitPrice, AVG(UnitPrice) AvgUnitPrice, SUM(OrderQty) SumOrderQty, AVG(OrderQty) AvgOrderQty FROM [dbo].[MySalesOrderDetail] GROUP BY ProductID ORDER BY ProductID GO It is very clear from the results that query is performance extremely fast after creating ColumnStore Index. The amount of the pages it has to read to run query is drastically reduced as the column which are needed in the query are stored in the same page and query does not have to go through every single page to read those columns. If we enable execution plan and compare we can see that column store index performance way better than regular index in this case. Let us clean up the database. -- Cleanup DROP INDEX [IX_MySalesOrderDetail_ColumnStore] ON [dbo].[MySalesOrderDetail] GO TRUNCATE TABLE dbo.MySalesOrderDetail GO DROP TABLE dbo.MySalesOrderDetail GO In future posts we will see cases where Columnstore index is not appropriate solution as well few other tricks and tips of the columnstore index. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Index, SQL Optimization, SQL Performance, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

Read the article

WebLogic Server JMS WLST Script – Who is Connected To My Server

- by james.bayer

Ever want to know who was connected to your WebLogic Server instance for troubleshooting? An email exchange about this topic and JMS came up this week, and I’ve heard it come up once or twice before too. Sometimes it’s interesting or helpful to know the list of JMS clients (IP Addresses, JMS Destinations, message counts) that are connected to a particular JMS server. This can be helpful for troubleshooting. Tom Barnes from the WebLogic Server JMS team provided some helpful advice: The JMS connection runtime mbean has “getHostAddress”, which returns the host address of the connecting client JVM as a string. A connection runtime can contain session runtimes, which in turn can contain consumer runtimes. The consumer runtime, in turn has a “getDestinationName” and “getMemberDestinationName”. I think that this means you could write a WLST script, for example, to dump all consumers, their destinations, plus their parent session’s parent connection’s host addresses. Note that the client runtime mbeans (connection, session, and consumer) won’t necessarily be hosted on the same JVM as a destination that’s in the same cluster (client messages route from their connection host to their ultimate destination in the same cluster). Writing the Script So armed with this information, I decided to take the challenge and see if I could write a WLST script to do this. It’s always helpful to have the WebLogic Server MBean Reference handy for activities like this. This one is focused on JMS Consumers and I only took a subset of the information available, but it could be modified easily to do Producers. I haven’t tried this on a more complex environment, but it works in my simple sandbox case, so it should give you the general idea. # Better to use Secure Config File approach for login as shown here http://buttso.blogspot.com/2011/02/using-secure-config-files-with-weblogic.html connect('weblogic','welcome1','t3://localhost:7001') # Navigate to the Server Runtime and get the Server Name serverRuntime() serverName = cmo.getName() # Multiple JMS Servers could be hosted by a single WLS server cd('JMSRuntime/' + serverName + '.jms' ) jmsServers=cmo.getJMSServers() # Find the list of all JMSServers for this server namesOfJMSServers = '' for jmsServer in jmsServers: namesOfJMSServers = jmsServer.getName() + ' ' # Count the number of connections jmsConnections=cmo.getConnections() print str(len(jmsConnections)) + ' JMS Connections found for ' + serverName + ' with JMSServers ' + namesOfJMSServers # Recurse the MBean tree for each connection and pull out some information about consumers for jmsConnection in jmsConnections: try: print 'JMS Connection:' print ' Host Address = ' + jmsConnection.getHostAddress() print ' ClientID = ' + str( jmsConnection.getClientID() ) print ' Sessions Current = ' + str( jmsConnection.getSessionsCurrentCount() ) jmsSessions = jmsConnection.getSessions() for jmsSession in jmsSessions: jmsConsumers = jmsSession.getConsumers() for jmsConsumer in jmsConsumers: print ' Consumer:' print ' Name = ' + jmsConsumer.getName() print ' Messages Received = ' + str(jmsConsumer.getMessagesReceivedCount()) print ' Member Destination Name = ' + jmsConsumer.getMemberDestinationName() except: print 'Error retrieving JMS Consumer Information' dumpStack() # Cleanup disconnect() exit() Example Output I expect the output to look something like this and loop through all the connections, this is just the first one: 1 JMS Connections found for AdminServer with JMSServers myJMSServer JMS Connection: Host Address = 127.0.0.1 ClientID = None Sessions Current = 16 Consumer: Name = consumer40 Messages Received = 1 Member Destination Name = myJMSModule!myQueue Notice that it has the IP Address of the client. There are 16 Sessions open because I’m using an MDB, which defaults to 16 connections, so this matches what I expect. Let’s see what the full output actually looks like: D:\Oracle\fmw11gr1ps3\user_projects\domains\offline_domain>java weblogic.WLST d:\temp\jms.py Initializing WebLogic Scripting Tool (WLST) ... Welcome to WebLogic Server Administration Scripting Shell Type help() for help on available commands Connecting to t3://localhost:7001 with userid weblogic ... Successfully connected to Admin Server 'AdminServer' that belongs to domain 'offline_domain'. Warning: An insecure protocol was used to connect to the server. To ensure on-the-wire security, the SSL port or Admin port should be used instead. Location changed to serverRuntime tree. This is a read-only tree with ServerRuntimeMBean as the root. For more help, use help(serverRuntime) 1 JMS Connections found for AdminServer with JMSServers myJMSServer JMS Connection: Host Address = 127.0.0.1 ClientID = None Sessions Current = 16 Consumer: Name = consumer40 Messages Received = 2 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer34 Messages Received = 2 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer37 Messages Received = 2 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer16 Messages Received = 2 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer46 Messages Received = 2 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer49 Messages Received = 2 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer43 Messages Received = 1 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer55 Messages Received = 1 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer25 Messages Received = 1 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer22 Messages Received = 1 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer19 Messages Received = 1 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer52 Messages Received = 1 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer31 Messages Received = 1 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer58 Messages Received = 1 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer28 Messages Received = 1 Member Destination Name = myJMSModule!myQueue Consumer: Name = consumer61 Messages Received = 1 Member Destination Name = myJMSModule!myQueue Disconnected from weblogic server: AdminServer Exiting WebLogic Scripting Tool. Thanks to Tom Barnes for the hints and the inspiration to write this up. Image of telephone switchboard courtesy of http://www.JoeTourist.net/ JoeTourist InfoSystems

Read the article

Liskov Substitution Principle and the Oft Forgot Third Wheel

- by Stacy Vicknair

Liskov Substitution Principle (LSP) is a principle of object oriented programming that many might be familiar with from the SOLID principles mnemonic from Uncle Bob Martin. The principle highlights the relationship between a type and its subtypes, and, according to Wikipedia, is defined by Barbara Liskov and Jeanette Wing as the following principle: Let be a property provable about objects of type . Then should be provable for objects of type where is a subtype of . Rectangles gonna rectangulate The iconic example of this principle is illustrated with the relationship between a rectangle and a square. Let’s say we have a class named Rectangle that had a property to set width and a property to set its height. 1: Public Class Rectangle 2: Overridable Property Width As Integer 3: Overridable Property Height As Integer 4: End Class We all at some point here that inheritance mocks an “IS A” relationship, and by gosh we all know square IS A rectangle. So let’s make a square class that inherits from rectangle. However, squares do maintain the same length on every side, so let’s override and add that behavior. 1: Public Class Square 2: Inherits Rectangle 3: 4: Private _sideLength As Integer 5: 6: Public Overrides Property Width As Integer 7: Get 8: Return _sideLength 9: End Get 10: Set(value As Integer) 11: _sideLength = value 12: End Set 13: End Property 14: 15: Public Overrides Property Height As Integer 16: Get 17: Return _sideLength 18: End Get 19: Set(value As Integer) 20: _sideLength = value 21: End Set 22: End Property 23: End Class Now, say we had the following test: 1: Public Sub SetHeight_DoesNotAffectWidth(rectangle As Rectangle) 2: 'arrange 3: Dim expectedWidth = 4 4: rectangle.Width = 4 5: 6: 'act 7: rectangle.Height = 7 8: 9: 'assert 10: Assert.AreEqual(expectedWidth, rectangle.Width) 11: End Sub If we pass in a rectangle, this test passes just fine. What if we pass in a square? This is where we see the violation of Liskov’s Principle! A square might "IS A” to a rectangle, but we have differing expectations on how a rectangle should function than how a square should! Great expectations Here’s where we pat ourselves on the back and take a victory lap around the office and tell everyone about how we understand LSP like a boss. And all is good… until we start trying to apply it to our work. If I can’t even change functionality on a simple setter without breaking the expectations on a parent class, what can I do with subtyping? Did Liskov just tell me to never touch subtyping again? The short answer: NO, SHE DIDN’T. When I first learned LSP, and from those I’ve talked with as well, I overlooked a very important but not appropriately stressed quality of the principle: our expectations. Our inclination is to want a logical catch-all, where we can easily apply this principle and wipe our hands, drop the mic and exit stage left. That’s not the case because in every different programming scenario, our expectations of the parent class or type will be different. We have to set reasonable expectations on the behaviors that we expect out of the parent, then make sure that those expectations are met by the child. Any expectations not explicitly expected of the parent aren’t expected of the child either, and don’t register as a violation of LSP that prevents implementation. You can see the flexibility mentioned in the Wikipedia article itself: A typical example that violates LSP is a Square class that derives from a Rectangle class, assuming getter and setter methods exist for both width and height. The Square class always assumes that the width is equal with the height. If a Square object is used in a context where a Rectangle is expected, unexpected behavior may occur because the dimensions of a Square cannot (or rather should not) be modified independently. This problem cannot be easily fixed: if we can modify the setter methods in the Square class so that they preserve the Square invariant (i.e., keep the dimensions equal), then these methods will weaken (violate) the postconditions for the Rectangle setters, which state that dimensions can be modified independently. Violations of LSP, like this one, may or may not be a problem in practice, depending on the postconditions or invariants that are actually expected by the code that uses classes violating LSP. Mutability is a key issue here. If Square and Rectangle had only getter methods (i.e., they were immutable objects), then no violation of LSP could occur. What this means is that the above situation with a rectangle and a square can be acceptable if we do not have the expectation for width to leave height unaffected, or vice-versa, in our application. Conclusion – the oft forgot third wheel Liskov Substitution Principle is meant to act as a guidance and warn us against unexpected behaviors. Objects can be stateful and as a result we can end up with unexpected situations if we don’t code carefully. Specifically when subclassing, make sure that the subclass meets the expectations held to its parent. Don’t let LSP think you cannot deviate from the behaviors of the parent, but understand that LSP is meant to highlight the importance of not only the parent and the child class, but also of the expectations WE set for the parent class and the necessity of meeting those expectations in order to help prevent sticky situations. Code examples, in both VB and C# Technorati Tags: LSV,Liskov Substitution Principle,Uncle Bob,Robert Martin,Barbara Liskov,Liskov

Read the article

ASP.NET WebAPI Security 2: Identity Architecture

- by Your DisplayName here!

Pedro has beaten me to the punch with a detailed post (and diagram) about the WebAPI hosting architecture. So go read his post first, then come back so we can have a closer look at what that means for security. The first important takeaway is that WebAPI is hosting independent- currently it ships with two host integration implementations – one for ASP.NET (aka web host) and WCF (aka self host). Pedro nicely shows the integration into the web host. Self hosting is not done yet so we will mainly focus on the web hosting case and I will point out security related differences when they exist. The interesting part for security (amongst other things of course) is the HttpControllerHandler (see Pedro’s diagram) – this is where the host specific representation of an HTTP request gets converted to the WebAPI abstraction (called HttpRequestMessage). The ConvertRequest method does the following: Create a new HttpRequestMessage. Copy URI, method and headers from the HttpContext. Copies HttpContext.User to the Properties<string, object> dictionary on the HttpRequestMessage. The key used for that can be found on HttpPropertyKeys.UserPrincipalKey (which resolves to “MS_UserPrincipal”). So the consequence is that WebAPI receives whatever IPrincipal has been set by the ASP.NET pipeline (in the web hosting case). Common questions are: Are there situations where is property does not get set? Not in ASP.NET – the DefaultAuthenticationModule in the HTTP pipeline makes sure HttpContext.User (and Thread.CurrentPrincipal – more on that later) are always set. Either to some authenticated user – or to an anonymous principal. This may be different in other hosting environments (again more on that later). Why so generic? Keep in mind that WebAPI is hosting independent and may run on a host that materializes identity completely different compared to ASP.NET (or .NET in general). This gives them a way to evolve the system in the future. How does WebAPI code retrieve the current client identity? HttpRequestMessage has an extension method called GetUserPrincipal() which returns the property as an IPrincipal. A quick look at self hosting shows that the moral equivalent of HttpControllerHandler.ConvertRequest() is HttpSelfHostServer.ProcessRequestContext(). Here the principal property gets only set when the host is configured for Windows authentication (inconsisteny). Do I like that? Well – yes and no. Here are my thoughts: I like that it is very straightforward to let WebAPI inherit the client identity context of the host. This might not always be what you want – think of an ASP.NET app that consists of UI and APIs – the UI might use Forms authentication, the APIs token based authentication. So it would be good if the two parts would live in a separate security world. It makes total sense to have this generic hand off point for identity between the host and WebAPI. It also makes total sense for WebAPI plumbing code (especially handlers) to use the WebAPI specific identity abstraction. But – c’mon we are running on .NET. And the way .NET represents identity is via IPrincipal/IIdentity. That’s what every .NET developer on this planet is used to. So I would like to see a User property of type IPrincipal on ApiController. I don’t like the fact that Thread.CurrentPrincipal is not populated. T.CP is a well established pattern as a one stop shop to retrieve client identity on .NET. That makes a lot of sense – even if the name is misleading at best. There might be existing library code you want to call from WebAPI that makes use of T.CP (e.g. PrincipalPermission, or a simple .Name or .IsInRole()). Having the client identity as an ambient property is useful for code that does not have access to the current HTTP request (for calling GetUserPrincipal()). I don’t like the fact that that the client identity conversion from host to WebAPI is inconsistent. This makes writing security plumbing code harder. I think the logic should always be: If the host has a client identity representation, copy it. If not, set an anonymous principal on the request message. Btw – please don’t annoy me with the “but T.CP is static, and static is bad for testing” chant. T.CP is a getter/setter and, in fact I find it beneficial to be able to set different security contexts in unit tests before calling in some logic. And, in case you have wondered – T.CP is indeed thread static (and the name comes from a time where a logical operation was bound to a thread – which is not true anymore). But all thread creation APIs in .NET actually copy T.CP to the new thread they create. This is the case since .NET 2.0 and is certainly an improvement compared to how Win32 does things. So to sum it up: The host plumbing copies the host client identity to WebAPI (this is not perfect yet, but will surely be improved). or in other words: The current WebAPI bits don’t ship with any authentication plumbing, but solely use whatever authentication (and thus client identity) is set up by the host. WebAPI developers can retrieve the client identity from the HttpRequestMessage. Hopefully my proposed changes around T.CP and the User property on ApiController will be added. In the next post, I will detail how to add WebAPI specific authentication support, e.g. for Basic Authentication and tokens. This includes integrating the notion of claims based identity. After that we will look at the built-in authorization bits and how to improve them as well. Stay tuned.

Read the article

Why is my external USB hard drive sometimes completely inaccessible?

- by Eliah Kagan

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

Read the article

JQuery and the multiple date selector

- by David Carter

Overview I recently needed to build a web page that would allow a user to capture some information and most importantly select multiple dates. This functionality was core to the application and hence had to be easy and quick to do. This is a public facing website so it had to be intuitive and very responsive. On the face of it it didn't seem too hard, I know enough juery to know what it is capable of and I was pretty sure that there would be some plugins that would help speed things along the way. I'm using ASP.Net MVC for this project as I really like the control that it gives you over the generated html and javascript. After years of Web Forms development it makes me feel like a web developer again and puts a smile on my face, that can only be a good thing! The Calendar The first item that I needed on this page was a calender and I wanted the ability to: have the calendar be always visible select/deselect multiple dates at the same time bind to the select/deselect event so that I could update a seperate listing of the selected dates allow the user to move to another month and still have the calender remember any dates in the previous month I was hoping that there was a jQuery plugin that would meet my requirements and luckily there was! The jQuery datepicker does everything I want and there is quite a bit of documentation on how to use it. It makes use of a javascript date library date.js which I had not come across before but has a number of very useful date utilities that I have used elsewhere in the project. As you can see from the image there still needs to be some styling done! But there will be plenty of time for that later. The calendar clearly shows which dates the user has selected in red and i also make use of an unordered list to show the the selected dates so the user can always clearly see what has been selected even if they move to another month on the calendar. The javascript code that is responsible for listening to events on the calendar and synchronising the list look as follows: <script type="text/javascript"> $(function () { $('.datepicker').datePicker({ inline: true, selectMultiple: true }) .bind( 'dateSelected', function (e, selectedDate, $td, state) { var dateInMillisecs = selectedDate.valueOf(); if (state) { //adding a date var newDate = new Date(selectedDate); //insert the new item into the correct place in the list var listitems = $('#dateList').children('li').get(); var liToAdd = "<li id='" + dateInMillisecs + "' >" + newDate.toString('ddd dd MMM yyyy') + "</li>"; var targetIndex = -1; for (var i = 0; i < listitems.length; i++) { if (dateInMillisecs <= listitems[i].id) { targetIndex = i; break; } } if (targetIndex < 0) { $('#dateList').append(liToAdd); } else { $($('#dateList').children("li")[targetIndex]).before(liToAdd); } } else {//removing a date $('ul #' + dateInMillisecs).remove(); } } ) }); When a date is selected on the calendar a function is called with a number of parameters passed to it. The ones I am particularly interested in are selectedDate and state. State tells me whether the user has selected or deselected the date passed in the selectedDate parameter. The <ul> that I am using to show the date has an id of dateList and this is what I will be adding and removing <li> items from. To make things a little more logical for the user I decided that the date should be sorted in chronological order, this means that each time a new date is selected it need to be placed in the correct position in the list. One way to do this would be just to append a new <li> to the list and then sort the whole list. However the approach I took was to get an array of all the items in the list var listitems = ('#dateList').children('li').get(); and then check the value of each item in the array against my new date and as soon as I found the case where the new date was less than the current item remember that position in the list as this is where I would insert it later. To make this work easily I decided to store a numeric representation of each date in the list in the id attribute of each <li> element. Fortunately javascript natively stores dates as the number of milliseconds since 1 Jan 1970. var dateInMillisecs = selectedDate.valueOf(); Please note that this is the value of the date in UTC! I always like to store dates in UTC as I learnt a long time ago that it saves a lot of refactoring at a later date... When I convert the dates back to their original back on the server I will need the UTC offset that was used when calculating the dates, this and how to actually serialise the dates and get them posted back will be the subject of another post.

Read the article

Windows 7 doesn't boot after Ubuntu install

- by Omu

I had windows 7 installed on my pc, then I installed Ubuntu 10.10/ During the installation process I have chosen to manually set my partitions: I set a 10GB drive for ubuntu root 1GB drive for swap and for boot drive I've chosen the one used by windows 7 Now I can boot ubuntu, I have the windows 7 option in the boot list, but when I choose Windows 7, it shows me a black screen for a second and returns back to boot screen. Boot Info Script 0.55 dated February 15th, 2010 ============================= Boot Info Summary: ============================== = Windows is installed in the MBR of /dev/sda sda1: _________________________________________________________________________ File system: ntfs Boot sector type: Grub 2 Boot sector info: Grub 2 is installed in the boot sector of sda1 and looks at sector 304908237 of the same hard drive for core.img, but core.img can not be found at this location. No errors found in the Boot Parameter Block. Operating System: Windows 7 Boot files/dirs: /bootmgr /Boot/BCD /Windows/System32/winload.exe sda2: _________________________________________________________________________ File system: ntfs Boot sector type: Windows XP Boot sector info: No errors found in the Boot Parameter Block. Operating System: Boot files/dirs: sda3: _________________________________________________________________________ File system: Extended Partition Boot sector type: - Boot sector info: sda5: _________________________________________________________________________ File system: ext4 Boot sector type: - Boot sector info: Operating System: Ubuntu 10.10 Boot files/dirs: /boot/grub/grub.cfg /etc/fstab /boot/grub/core.img sda4: _________________________________________________________________________ File system: swap Boot sector type: - Boot sector info: =========================== Drive/Partition Info: ============================= Drive: sda ___________________ _____________________________________________________ Disk /dev/sda: 160.0 GB, 160041885696 bytes 255 heads, 63 sectors/track, 19457 cylinders, total 312581808 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes Partition Boot Start End Size Id System /dev/sda1 * 63 62,894,474 62,894,412 7 HPFS/NTFS /dev/sda2 62,894,478 291,579,749 228,685,272 7 HPFS/NTFS /dev/sda3 291,579,811 309,157,937 17,578,127 5 Extended /dev/sda5 291,579,813 309,157,937 17,578,125 83 Linux /dev/sda4 309,159,936 312,580,095 3,420,160 82 Linux swap / Solaris blkid -c /dev/null: ____________________________________________________________ Device UUID TYPE LABEL /dev/sda1 1266BB2766BB0A8D ntfs /dev/sda2 BEDBF1147C76F703 ntfs DATA /dev/sda3: PTTYPE="dos" /dev/sda4 dd38226d-c7c9-4ae5-a726-6d18d34a22e4 swap /dev/sda5 e1dafd1c-f855-406b-8f9a-f9d527c70255 ext4 /dev/sda: PTTYPE="dos" ============================ "mount | grep ^/dev output: =========================== Device Mount_Point Type Options /dev/sda5 / ext4 (rw,errors=remount-ro,commit=0) =========================== sda5/boot/grub/grub.cfg: =========================== # # DO NOT EDIT THIS FILE # # It is automatically generated by grub-mkconfig using templates # from /etc/grub.d and settings from /etc/default/grub # ### BEGIN /etc/grub.d/00_header ### if [ -s $prefix/grubenv ]; then set have_grubenv=true load_env fi set default="0" if [ "${prev_saved_entry}" ]; then set saved_entry="${prev_saved_entry}" save_env saved_entry set prev_saved_entry= save_env prev_saved_entry set boot_once=true fi function savedefault { if [ -z "${boot_once}" ]; then saved_entry="${chosen}" save_env saved_entry fi } function recordfail { set recordfail=1 if [ -n "${have_grubenv}" ]; then if [ -z "${boot_once}" ]; then save_env recordfail; fi; fi } function load_video { insmod vbe insmod vga } insmod part_msdos insmod ext2 set root='(hd0,msdos5)' search --no-floppy --fs-uuid --set e1dafd1c-f855-406b-8f9a-f9d527c70255 if loadfont /usr/share/grub/unicode.pf2 ; then set gfxmode=640x480 load_video insmod gfxterm fi terminal_output gfxterm insmod part_msdos insmod ext2 set root='(hd0,msdos5)' search --no-floppy --fs-uuid --set e1dafd1c-f855-406b-8f9a-f9d527c70255 set locale_dir=($root)/boot/grub/locale set lang=en insmod gettext if [ "${recordfail}" = 1 ]; then set timeout=-1 else set timeout=10 fi ### END /etc/grub.d/00_header ### ### BEGIN /etc/grub.d/05_debian_theme ### set menu_color_normal=white/black set menu_color_highlight=black/light-gray ### END /etc/grub.d/05_debian_theme ### ### BEGIN /etc/grub.d/10_linux ### menuentry 'Ubuntu, with Linux 2.6.35-22-generic' --class ubuntu --class gnu-linux --class gnu --class os { recordfail insmod part_msdos insmod ext2 set root='(hd0,msdos5)' search --no-floppy --fs-uuid --set e1dafd1c-f855-406b-8f9a-f9d527c70255 linux /boot/vmlinuz-2.6.35-22-generic root=UUID=e1dafd1c-f855-406b-8f9a-f9d527c70255 ro quiet splash initrd /boot/initrd.img-2.6.35-22-generic } menuentry 'Ubuntu, with Linux 2.6.35-22-generic (recovery mode)' --class ubuntu --class gnu-linux --class gnu --class os { recordfail insmod part_msdos insmod ext2 set root='(hd0,msdos5)' search --no-floppy --fs-uuid --set e1dafd1c-f855-406b-8f9a-f9d527c70255 echo 'Loading Linux 2.6.35-22-generic ...' linux /boot/vmlinuz-2.6.35-22-generic root=UUID=e1dafd1c-f855-406b-8f9a-f9d527c70255 ro single echo 'Loading initial ramdisk ...' initrd /boot/initrd.img-2.6.35-22-generic } ### END /etc/grub.d/10_linux ### ### BEGIN /etc/grub.d/20_linux_xen ### ### END /etc/grub.d/20_linux_xen ### ### BEGIN /etc/grub.d/20_memtest86+ ### menuentry "Memory test (memtest86+)" { insmod part_msdos insmod ext2 set root='(hd0,msdos5)' search --no-floppy --fs-uuid --set e1dafd1c-f855-406b-8f9a-f9d527c70255 linux16 /boot/memtest86+.bin } menuentry "Memory test (memtest86+, serial console 115200)" { insmod part_msdos insmod ext2 set root='(hd0,msdos5)' search --no-floppy --fs-uuid --set e1dafd1c-f855-406b-8f9a-f9d527c70255 linux16 /boot/memtest86+.bin console=ttyS0,115200n8 } ### END /etc/grub.d/20_memtest86+ ### ### BEGIN /etc/grub.d/30_os-prober ### menuentry "Windows 7 (loader) (on /dev/sda1)" { insmod part_msdos insmod ntfs set root='(hd0,msdos1)' search --no-floppy --fs-uuid --set 1266bb2766bb0a8d chainloader +1 } ### END /etc/grub.d/30_os-prober ### ### BEGIN /etc/grub.d/40_custom ### # This file provides an easy way to add custom menu entries. Simply type the # menu entries you want to add after this comment. Be careful not to change # the 'exec tail' line above. ### END /etc/grub.d/40_custom ### ### BEGIN /etc/grub.d/41_custom ### if [ -f $prefix/custom.cfg ]; then source $prefix/custom.cfg; fi ### END /etc/grub.d/41_custom ### =============================== sda5/etc/fstab: =============================== # /etc/fstab: static file system information. # # Use 'blkid -o value -s UUID' to print the universally unique identifier # for a device; this may be used with UUID= as a more robust way to name # devices that works even if disks are added and removed. See fstab(5). # # proc /proc proc nodev,noexec,nosuid 0 0 /dev/sda5 / ext4 errors=remount-ro 0 1 # swap was on /dev/sda4 during installation UUID=dd38226d-c7c9-4ae5-a726-6d18d34a22e4 none swap sw 0 0 =================== sda5: Location of files loaded by Grub: =================== 156.1GB: boot/grub/core.img 156.3GB: boot/grub/grub.cfg 149.9GB: boot/initrd.img-2.6.35-22-generic 156.3GB: boot/vmlinuz-2.6.35-22-generic 149.9GB: initrd.img 156.3GB: vmlinuz

Read the article

Windows 8 Live Accounts and the actual Windows Account

- by Rick Strahl

As if Windows Security wasn't confusing enough, in Windows 8 we get thrown yet another curve ball with Windows Live accounts to logon. When I set up my Windows 8 machine I originally set it up with a 'real', non-live account that I always use on my Windows machines. I did this mainly so I have a matching account for resources around my home and intranet network so I could log on to network resources properly. At some point later I decided to set up Windows Live security just to see how changes things. Windows wants you to use Windows Live Windows 8 logins are required in order for the Windows RT account info to work. Not that I care - since installing Windows 8 I've maybe spent 10 minutes with Windows RT because - well it's pretty freaking sucky on the desktop. From shitty apps to mis-managed screen real estate I can't say that there's anything compelling there to date, but then I haven't looked that hard either. Anyway… I set up the Windows Live account to see if that changes things. It does - I do get all my live logins to work from Live Account so that Twitter and Facebook posts and pictures and calendars all show up on live tiles on the start screen and in the actual apps. That's nice-ish, but hardly that exciting given that all of the apps tied to those live tiles are average at best. And it would have been nice if all of this could be done without being forced into running with a Windows Live User Account - this all feels like strong-arming you into moving into Microsofts walled garden… and that's probably what it's meant to do. Who am I? The real problem to me though is that these Windows Live and raw Windows User accounts are a bit unpredictable especially when it comes to developer information about the account and which credentials to use. So for example Windows reports folder security like this: Notice it's showing my Windows Live account. Now if I go to Edit and try to add my Windows user account (rstrahl) it'll just automatically show up as the live account. On the other hand though the underlying system sees everything as my real Windows account. After I switched to a Windows Live login account and I have to login to Windows with my Live account, what do you suppose this returns?Console.WriteLine(Environment.UserName); It returns my raw Windows user account (rstrahl). All my permissions, all my actual settings and the desktop console altogether run under that account. If I look in TaskManager (or Process Explorer for me) I see: Everything running on the desktop shell with my login running under my Windows user account. I suppose it makes sense, but where is that association happening? When I switched to a Windows Live account, nowhere did I associate my real account with the Live account - it just happened. And looking through the account configuration dialogs I can't find any reference to the raw Windows account. Other than switching back I see no mention anywhere of the raw Windows account - everything refers to the Live account. Right then, clear as potato soup! So this is who you really are! The problem is that in some situations this schizophrenic account behavior gets a bit weird. Today I was running a local Web application in IIS that uses Windows Authentication - I tried to log-in with my real Windows account login because that's what I'm used to using with WINDOWS freaking Authentication through IIS. But… it failed. I checked my IIS settings, my apps login settings and I just could not for the life of me get into the site with my Windows username. That is until I finally realized that I should try using my Windows Live credentials instead. And that worked. So now in this Windows Authentication dialog I had to type in my Live ID and password, which is - just weird. Then in IIS if I look at a Trace page (or in my case my app's Status page) I see that the logged on account is - my Windows user account. What's really annoying about this is that in some places it uses the live account in other places it uses my Windows account. If I remote desktop into my Web server online - I have to use the local authentication dialog but I have to put in my real Windows credentials not the Live account. Oh yes, it's all so terribly intuitive and logical… So in summary, when you log on with a Live account you are actually mapped to an underlying Windows user. In any application if you check the user name it'll be the underlying user account (not sure what happens in a Windows RT app or even what mechanism is used there to get the user name info). When logging on to local machine resource with user name and password you have to use your Live IDs even if the permissions on the resources are mapped to your underlying Windows account. Easy enough I suppose, but still not exactly intuitive behavior…© Rick Strahl, West Wind Technologies, 2005-2012Posted in Windows Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

Read the article

Integration with Multiple Versions of BizTalk HL7 Accelerator Schemas

- by Paul Petrov

Microsoft BizTalk Accelerator for HL7 comes with multiple versions of the HL7 implementation. One of the typical integration tasks is to receive one format and transmit another. For example, system A works HL7 v2.4 messages, system B with v2.3, and system C with v2.2. The system A is exchanging messages with B and C. The logical solution is to create schemas in separate namespaces for each system and assign maps on send ports. Schematic diagram of the messaging solution is shown below: Nothing is complex about that conceptually. On the implementation level things can get nasty though because of the elaborate nature of HL7 schemas and sheer amount of message types involved. If trying to implement maps directly in BizTalk Map Editor one would quickly get buried by thousands of links between subfields of HL7 segments. Since task is repetitive because HL7 segments are reused between message types it's natural to take advantage of such modular structure and reduce amount of work through reuse. Here's where it makes sense to switch from visual map editor to old plain XSLT. The implementation is done in three steps. First, create XSL templates to map from segments of one version to another. This can be done using BizTalk Map Editor subsequently copying and modifying generated XSL code to create one xsl:template per segment. Group all segments for format mapping in one XSL file (we call it SegmentTemplates.xsl). Here's how template for the PID segment (Patient Identification) would look like this: <xsl:template name="PID"> <PID_PatientIdentification> <xsl:if test="PID_PatientIdentification/PID_1_SetIdPatientId"> <PID_1_SetIdPid> <xsl:value-of select="PID_PatientIdentification/PID_1_SetIdPatientId/text()" /> </PID_1_SetIdPid> </xsl:if> <xsl:for-each select="PID_PatientIdentification/PID_2_PatientIdExternalId"> <PID_2_PatientId> <xsl:if test="CX_0_Id"> <CX_0_Id> <xsl:value-of select="CX_0_Id/text()" /> </CX_0_Id> </xsl:if> <xsl:if test="CX_1_CheckDigit"> <CX_1_CheckDigitSt> <xsl:value-of select="CX_1_CheckDigit/text()" /> </CX_1_CheckDigitSt> </xsl:if> <xsl:if test="CX_2_CodeIdentifyingTheCheckDigitSchemeEmployed"> <CX_2_CodeIdentifyingTheCheckDigitSchemeEmployed> <xsl:value-of select="CX_2_CodeIdentifyingTheCheckDigitSchemeEmployed/text()" /> </CX_2_CodeIdentifyingTheCheckDigitSchemeEmployed> . . . // skipped for brevity This is the most tedious and time consuming part. Templates can be created for only those segments that are used in message interchange. Once this is done the rest goes much easier. The next step is to create message type specific XSL that references (imports) segment templates XSL file. Inside this file simple call segment templates in appropriate places. For example, beginning of the mapping XSL for ADT_A01 message would look like this: <xsl:import href="SegmentTemplates_23_to_24.xslt" /> <xsl:output omit-xml-declaration="yes" method="xml" version="1.0" /> <xsl:template match="/"> <xsl:apply-templates select="s0:ADT_A01_23_GLO_DEF" /> </xsl:template> <xsl:template match="s0:ADT_A01_23_GLO_DEF"> <ns0:ADT_A01_24_GLO_DEF> <xsl:call-template name="EVN" /> <xsl:call-template name="PID" /> <xsl:for-each select="PD1_PatientDemographic"> <xsl:call-template name="PD1" /> </xsl:for-each> <xsl:call-template name="PV1" /> <xsl:for-each select="PV2_PatientVisitAdditionalInformation"> <xsl:call-template name="PV2" /> </xsl:for-each> This code simply calls segment template directly for required singular elements and in for-each loop for optional/repeating elements. And lastly, create BizTalk map (btm) that references message type specific XSL. It is essentially empty map with Custom XSL Path set to appropriate XSL: In the end, you will end up with one segment templates file that is referenced by many message type specific XSL files which in turn used by BizTalk maps. Once all segment maps are created they are widely reusable and all the rest work is very simple and clean.

Read the article

Yet another blog about IValueConverter

- by codingbloke

After my previous blog on a Generic Boolean Value Converter I thought I might as well blog up another IValueConverter implementation that I use. The Generic Boolean Value Converter effectively converters an input which only has two possible values to one of two corresponding objects. The next logical step would be to create a similar converter that can take an input which has multiple (but finite and discrete) values to one of multiple corresponding objects. To put it more simply a Generic Enum Value Converter. Now we already have a tool that can help us in this area, the ResourceDictionary. A simple IValueConverter implementation around it would create a StringToObjectConverter like so:- StringToObjectConverter using System; using System.Windows; using System.Windows.Data; using System.Linq; using System.Windows.Markup; namespace SilverlightApplication1 { [ContentProperty("Items")] public class StringToObjectConverter : IValueConverter { public ResourceDictionary Items { get; set; } public string DefaultKey { get; set; } public StringToObjectConverter() { DefaultKey = "__default__"; } public virtual object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { if (value != null && Items.Contains(value.ToString())) return Items[value.ToString()]; else return Items[DefaultKey]; } public virtual object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { return Items.FirstOrDefault(kvp => value.Equals(kvp.Value)).Key; } } } There are some things to note here. The bulk of managing the relationship between an object instance and the related string key is handled by the Items property being an ResourceDictionary. Also there is a catch all “__default__” key value which allows for only a subset of the possible input values to mapped to an object with the rest falling through to the default. We can then set one of these up in Xaml:- <local:StringToObjectConverter x:Key="StatusToBrush"> <ResourceDictionary> <SolidColorBrush Color="Red" x:Key="Overdue" /> <SolidColorBrush Color="Orange" x:Key="Urgent" /> <SolidColorBrush Color="Silver" x:Key="__default__" /> </ResourceDictionary> </local:StringToObjectConverter> You could well imagine that in the model being bound these key names would actually be members of an enum. This still works due to the use of ToString in the Convert method. Hence the only requirement for the incoming object is that it has a ToString implementation which generates a sensible string instead of simply the type name. I can’t imagine right now a scenario where this converter would be used in a TwoWay binding but there is no reason why it can’t. I prefer to avoid leaving the ConvertBack throwing an exception if that can be be avoided. Hence it just enumerates the KeyValuePair entries to find a value that matches and returns the key its mapped to. Ah but now my sense of balance is assaulted again. Whilst StringToObjectConverter is quite happy to accept an enum type via the Convert method it returns a string from the ConvertBack method not the original input enum type that arrived in the Convert. Now I could address this by complicating the ConvertBack method and examining the targetType parameter etc. However I prefer to a different approach, deriving a new EnumToObjectConverter class instead. EnumToObjectConverter using System; namespace SilverlightApplication1 { public class EnumToObjectConverter : StringToObjectConverter { public override object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { string key = Enum.GetName(value.GetType(), value); return base.Convert(key, targetType, parameter, culture); } public override object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture) { string key = (string)base.ConvertBack(value, typeof(String), parameter, culture); return Enum.Parse(targetType, key, false); } } } This is a more belts and braces solution with specific use of Enum.GetName and Enum.Parse. Whilst its more explicit in that the a developer has to choose to use it, it is only really necessary when using TwoWay binding, in OneWay binding the base StringToObjectConverter would serve just as well. The observant might note that there is actually no “Generic” aspect to this solution in the end. The use of a ResourceDictionary eliminates the need for that.

Read the article

MySQL Connect 9 Days Away – Optimizer Sessions

- by Bertrand Matthelié

72 1024x768 Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Following my previous blog post focusing on InnoDB talks at MySQL Connect, let us review today the sessions focusing on the MySQL Optimizer: Saturday, 11.30 am, Room Golden Gate 6: MySQL Optimizer Overview—Olav Sanstå, Oracle The goal of MySQL optimizer is to take a SQL query as input and produce an optimal execution plan for the query. This session presents an overview of the main phases of the MySQL optimizer and the primary optimizations done to the query. These optimizations are based on a combination of logical transformations and cost-based decisions. Examples of optimization strategies the presentation covers are the main query transformations, the join optimizer, the data access selection strategies, and the range optimizer. For the cost-based optimizations, an overview of the cost model and the data used for doing the cost estimations is included. Saturday, 1.00 pm, Room Golden Gate 6: Overview of New Optimizer Features in MySQL 5.6—Manyi Lu, Oracle Many optimizer features have been added into MySQL 5.6. This session provides an introduction to these great features. Multirange read, index condition pushdown, and batched key access will yield huge performance improvements on large data volumes. Structured explain, explain for update/delete/insert, and optimizer tracing will help users analyze and speed up queries. And last but not least, the session covers subquery optimizations in Release 5.6. Saturday, 7.00 pm, Room Golden Gate 4: BoF: Query Optimizations: What Is New and What Is Coming? This BoF presents common techniques for query optimization, covers what is new in MySQL 5.6, and provides a discussion forum in which attendees can tell the MySQL optimizer team which optimizations they would like to see in the future. Sunday, 1.15 pm, Room Golden Gate 8: Query Performance Comparison of MySQL 5.5 and MySQL 5.6—Øystein Grøvlen, Oracle MySQL Release 5.6 contains several improvements in the query optimizer that create improved performance for complex queries. This presentation looks at how MySQL 5.6 improves the performance of many of the queries in the DBT-3 benchmark. Based on the observed improvements, the presentation discusses what makes the specific queries perform better in Release 5.6. It describes the relevant new optimization techniques and gives examples of the types of queries that will benefit from these techniques. Sunday, 4.15 pm, Room Golden Gate 4: Powerful EXPLAIN in MySQL 5.6—Evgeny Potemkin, Oracle The EXPLAIN command of MySQL has long been a very useful tool for understanding how MySQL will execute a query. Release 5.6 of the MySQL database offers several new additions that give more-detailed information about the query plan and make it easier to understand at the same time. This presentation gives an overview of new EXPLAIN features: structured EXPLAIN in JSON format, EXPLAIN for INSERT/UPDATE/DELETE, and optimizer tracing. Examples in the session give insights into how you can take advantage of the new features. They show how these features supplement and relate to each other and to classical EXPLAIN and how and why the MySQL server chooses a particular query plan. You can check out the full program here as well as in the September edition of the MySQL newsletter. Not registered yet? You can still save US$ 300 over the on-site fee – Register Now!

Read the article

Announcing the New Windows Azure Web Sites Shared Scaling Tier

- by Clint Edmonson

Windows Azure Web Sites has added a new pricing tier that will solve the #1 blocker for the web development community. The shared tier now supports custom domain names mapped to shared-instance web sites. This post will outline the plan changes and elaborate on how the new pricing model makes Windows Azure Web Sites an even richer option for web development shops of all sizes. Free Shared Reserved # of Sites 10 100 100 Egress 165MB/Day 5GB/Month Included 5GB/Month Included Storage 1GB 1GB 10GB Throttling CPU/Memory/Egress CPU/Memory Unlimited Price Free $.02/hr per site, per instance $.08/hr per core Setting the Stage In June, we released the first public preview of Windows Azure Web Sites, which gave web developers a great platform on which to get web sites running using their web development framework of choice. PHP, Node.js, classic ASP, and ASP.NET developers can all utilize the Windows Azure platform to create and launch their web sites. Likewise, these developers have a series of data storage options using Windows Azure SQL Databases, MySQL, or Windows Azure Storage. The Windows Azure Web Sites free offer enabled startups to get their site up and running on Windows Azure with a minimal investment, and with multiple deployment and continuous integration features such as Git, Team Foundation Services, FTP, and Web Deploy. The response to the Windows Azure Web Sites offer has been overwhelmingly positive. Since the addition of the service on June 12th, tens of thousands of web sites have been deployed to Windows Azure and the volume of adoption is increasing every week. Preview Feedback In spite of the growth and success of the product, the community has had questions about features lacking in the free preview offer. The main question web developers asked regarding Windows Azure Web Sites relates to the lack of the free offer’s support for domain name mapping. During the preview launch period, customer feedback made it obvious that the lack of domain name mapping support was an area of concern. We’re happy to announce that this #1 request has been delivered as a feature of the new shared plan. New Shared Tier Portal Features In the screen shot below, the “Scale” tab in the portal shows the new tiers – Free, Shared, and Reserved – and gives the user the ability to quickly move any of their free web sites into the shared tier. With a single mouse-click, the user can move their site into the shared tier. Once a site has been moved into the shared tier, a new Manage Domains button appears in the bottom action bar of the Windows Azure Portal giving site owners the ability to manage their domain names for a shared site. This button brings up the domain-management dialog, which can be used to enter in a specific domain name that will be mapped to the Windows Azure Web Site. Shared Tier Benefits Startups and large web agencies will both benefit from this plan change. Here are a few examples of scenarios which fit the new pricing model: Startups no longer have to select the reserved plan to map domain names to their sites. Instead, they can use the free option to develop their sites and choose on a site-by-site basis which sites they elect to move into the shared plan, paying only for the sites that are finished and ready to be domain-mapped Agencies who manage dozens of sites will realize a lower cost of ownership over the long term by moving their sites into reserved mode. Once multi-site companies reach a certain price point in the shared tier, it is much more cost-effective to move sites to a reserved tier. Long-term, it’s easy to see how the new Windows Azure Web Sites shared pricing tier makes Windows Azure Web Sites it a great choice for both startups and agency customers, as it enables rapid growth and upgrades while keeping the cost to a minimum. Large agencies will be able to have all of their sites in their own instances, and startups will have the capability to scale up to multiple-shared instances for minimal cost and eventually move to reserved instances without worrying about the need to incur continually additional costs. Customers can feel confident they have the power of the Microsoft Windows Azure brand and our world-class support, at prices competitive in the market. Plus, in addition to realizing the cost savings, they’ll have the whole family of Windows Azure features available. Continuous Deployment from GitHub and CodePlex Along with this new announcement are two other exciting new features. I’m proud to announce that web developers can now publish their web sites directly from CodePlex or GitHub.com repositories. Once connections are established between these services and your web sites, Windows Azure will automatically be notified every time a check-in occurs. This will then trigger Windows Azure to pull the source and compile/deploy the new version of your app to your web site automatically. Walk-through videos on how to perform these functions are below: Publishing to an Azure Web Site from CodePlex Publishing to an Azure Web Site from GitHub.com These changes, as well as the enhancements to the reserved plan model, make Windows Azure Web Sites a truly competitive hosting option. It’s never been easier or cheaper for a web developer to get up and running. Check out the free Windows Azure web site offering and see for yourself. Stay tuned to my twitter feed for Windows Azure announcements, updates, and links: @clinted

Read the article

Mixed Emotions: Humans React to Natural Language Computer

- by Applications User Experience

There was a big event in Silicon Valley on Tuesday, November 15. Watson, the natural language computer developed at IBM Watson Research Center in Yorktown Heights, New York, and its inventor and principal research investigator, David Ferrucci, were guests at the Computer History Museum in Mountain View, California for another round of the television game Jeopardy. You may have read about or watched on YouTube how Watson beat Ken Jennings and Brad Rutter, two top Jeopardy competitors, last February. This time, Watson swept the floor with two Silicon Valley high-achievers, one a venture capitalist with a background in math, computer engineering, and physics, and the other a technology and finance writer well-versed in all aspects of culture and humanities. Watson is the product of the DeepQA research project, which attempts to create an artificially intelligent computing system through advances in natural language processing (NLP), among other technologies. NLP is a computing strategy that seeks to provide answers by processing large amounts of unstructured data contained in multiple large domains of human knowledge. There are several ways to perform NLP, but one way to start is by recognizing key words, then processing contextual cues associated with the keyword concepts so that you get many more “smart” (that is, human-like) deductions, rather than a series of “dumb” matches. Jeopardy questions often require more than key word matching to get the correct answer; typically several pieces of information put together, often from vastly different categories, to come up with a satisfactory word string solution that can be rephrased as a question. Smarter than your average search engine, but is it as smart as a human? Watson was especially fast at descrambling mixed-up state capital names, and recalling and pairing movie titles where one started and the other ended in the same word (e.g., Billion Dollar Baby Boom, where both titles used the word Baby). David said they had basically removed the variable of how fast Watson hit the buzzer compared to human contestants, but frustration frequently appeared on the faces of the contestants beaten to the punch by Watson. David explained that top Jeopardy winners like Jennings achieved their success with a similar strategy, timing their buzz to the end of the reading of the clue, and “running the board”, being first to respond on about 60% of the clues. Similar results for Watson. It made sense that Watson would be good at the technical and scientific stuff, so I figured the venture capitalist was toast. But I thought for sure Watson would lose to the writer in categories such as pop culture, wines and foods, and other humanities. Surprisingly, it held its own. I was amazed it could recognize a word definition of a syllogism in the category of philosophy. So what was the audience reaction to all of this? We started out expecting our formidable human contestants to easily run some of their categories; however, they started off on the wrong foot with the state capitals which Watson could unscramble so efficiently. By the end of the first round, contestants and the audience were feeling a little bit, well, …. deflated. Watson was winning by about $13,000, and the humans had gone into negative dollars. The IBM host said he was going to “slow Watson down a bit,” and the humans came back with respectable scores in Double Jeopardy. This was partially thanks to a very sympathetic audience (and host, also a human) providing “group-think” on many questions, especially baseball ‘s most valuable players, which by the way, couldn’t have been hard because even I knew them. Yes, that’s right, the humans cheated. Since Watson could speak but not hear us (it didn’t have speech recognition capability), it was probably unaware of this. In Final Jeopardy, the single question had to do with law. I was sure Watson would blow this one, but all contestants were able to answer correctly about a copyright law. In a career devoted to making computers more helpful to people, I think I may have seen how a computer can do too much. I’m not sure I’d want to work side-by-side with a Watson doing my job. Certainly listening and empathy are important traits we humans still have over Watson. While there was great enthusiasm in the packed room of computer scientists and their friends for this standing-room-only show, I think it made several of us uneasy (especially the poor human contestants whose egos were soundly bashed in the first round). This computer system, by the way , only took 4 years to program. David Ferrucci mentioned several practical uses for Watson, including medical diagnoses and legal strategies. Are you “the expert” in your job? Imagine NLP computing on an Oracle database. This may be the user interface of the future to enable users to better process big data. How do you think you’d like it? Postscript: There were three little boys sitting in front of me in the very first row. They looked, how shall I say it, … unimpressed!

Read the article

I have a problem with a AE1200 Cisco/Linksys Wireless-N USB adapter having stopped working after I ran the update manager in Ubuntu 12.04

- by user69670

Here is the problem, I use a Cisco/Linksys AE1200 wireless network adapter to connect my desktop to a public wifi internet connection. I use ndiswrapper to use the windows driver and it had been working fine for me untill I ran the update manager overnight a few days ago. When I woke up it was asking for the normal computer restart to implement the changes but after rebooting the computer, the wireless adapter did not work, the status light on the adapter did not light up even though ubuntu recognizes it is there and according to ndiswrapper the drivers are loaded and the hardware is present. the grep command is being a bitch for some unknown reason today so this will be long sorry Output from "lspci": 00:00.0 Host bridge: Advanced Micro Devices [AMD] nee ATI Radeon Xpress 200 Host Bridge (rev 01) 00:01.0 PCI bridge: Advanced Micro Devices [AMD] nee ATI RS480 PCI Bridge 00:12.0 SATA controller: Advanced Micro Devices [AMD] nee ATI SB600 Non-Raid-5 SATA 00:13.0 USB controller: Advanced Micro Devices [AMD] nee ATI SB600 USB (OHCI0) 00:13.1 USB controller: Advanced Micro Devices [AMD] nee ATI SB600 USB (OHCI1) 00:13.2 USB controller: Advanced Micro Devices [AMD] nee ATI SB600 USB (OHCI2) 00:13.3 USB controller: Advanced Micro Devices [AMD] nee ATI SB600 USB (OHCI3) 00:13.4 USB controller: Advanced Micro Devices [AMD] nee ATI SB600 USB (OHCI4) 00:13.5 USB controller: Advanced Micro Devices [AMD] nee ATI SB600 USB Controller (EHCI) 00:14.0 SMBus: Advanced Micro Devices [AMD] nee ATI SBx00 SMBus Controller (rev 13) 00:14.1 IDE interface: Advanced Micro Devices [AMD] nee ATI SB600 IDE 00:14.3 ISA bridge: Advanced Micro Devices [AMD] nee ATI SB600 PCI to LPC Bridge 00:14.4 PCI bridge: Advanced Micro Devices [AMD] nee ATI SBx00 PCI to PCI Bridge 01:05.0 VGA compatible controller: Advanced Micro Devices [AMD] nee ATI RC410 [Radeon Xpress 200] 02:02.0 Communication controller: Conexant Systems, Inc. HSF 56k Data/Fax Modem 02:03.0 Multimedia audio controller: Creative Labs CA0106 Soundblaster 02:05.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+ (rev 10) Output from "lsusb": Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 006 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 001 Device 009: ID 13b1:0039 Linksys AE1200 802.11bgn Wireless Adapter [Broadcom BCM43235] Bus 003 Device 002: ID 045e:0053 Microsoft Corp. Optical Mouse Bus 004 Device 002: ID 1043:8006 iCreate Technologies Corp. Flash Disk 32-256 MB Output from "ifconfig": eth0 Link encap:Ethernet HWaddr 00:19:21:b6:af:7c UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) Interrupt:20 Base address:0xb400 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:13232 errors:0 dropped:0 overruns:0 frame:0 TX packets:13232 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:1084624 (1.0 MB) TX bytes:1084624 (1.0 MB) Output from "iwconfig": lo no wireless extensions. eth0 no wireless extensions. Output from "lsmod": Module Size Used by nls_iso8859_1 12617 1 nls_cp437 12751 1 vfat 17308 1 fat 55605 1 vfat uas 17828 0 usb_storage 39646 1 nls_utf8 12493 1 udf 84366 1 crc_itu_t 12627 1 udf snd_ca0106 39279 2 snd_ac97_codec 106082 1 snd_ca0106 ac97_bus 12642 1 snd_ac97_codec snd_pcm 80845 2 snd_ca0106,snd_ac97_codec rfcomm 38139 0 snd_seq_midi 13132 0 snd_rawmidi 25424 2 snd_ca0106,snd_seq_midi bnep 17830 2 parport_pc 32114 0 bluetooth 158438 10 rfcomm,bnep ppdev 12849 0 snd_seq_midi_event 14475 1 snd_seq_midi snd_seq 51567 2 snd_seq_midi,snd_seq_midi_event snd_timer 28931 2 snd_pcm,snd_seq snd_seq_device 14172 3 snd_seq_midi,snd_rawmidi,snd_seq snd 62064 11 snd_ca0106, snd_ac97_codec,snd_pcm,snd_rawj9fe snd_ca0106,snd_ac97_codec,snd_pcm,snd_rawmidi,snd_seq,snd_timer,snd_seq_device soundcore 14635 1 snd snd_page_alloc 14108 2 snd_ca0106,snd_pcm sp5100_tco 13495 0 i2c_piix4 13093 0 radeon 733693 3 ttm 65344 1 radeon drm_kms_helper 45466 1 radeon drm 197692 5 radeon,ttm,drm_kms_helper i2c_algo_bit 13199 1 radeon mac_hid 13077 0 shpchp 32325 0 ati_agp 13242 0 lp 17455 0 parport 40930 3 parport_pc,ppdev,lp usbhid 41906 0 hid 77367 1 usbhid 8139too 23283 0 8139cp 26759 0 pata_atiixp 12999 1 Output from "sudo lshw -C network": *-network description: Ethernet interface product: RTL-8139/8139C/8139C+ vendor: Realtek Semiconductor Co., Ltd. physical id: 5 bus info: pci@0000:02:05.0 logical name: eth0 version: 10 serial: 00:19:21:b6:af:7c size: 10Mbit/s capacity: 100Mbit/s width: 32 bits clock: 33MHz capabilities: pm bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 10 0bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=8139too driverversion=0.9.28 duplex=half latency=64 link=no maxlatency=64 mingnt=32 multicast=yes port=MII speed=10Mbit/s resources: irq:20 ioport:b400(size=256) memory:ff5fdc00-ff5fdcff Output from "iwlist scan": lo Interface doesn't support scanning. eth0 Interface doesn't support scanning. Output from "lsb_release -d": Ubuntu 12.04 LTS Output from "uname -mr": 3.2.0-24-generic-pae i686 Output from "sudo /etc/init.d/networking restart": * Running /etc/init.d/networking restart is deprecated because it may not enable again some interfaces * Reconfiguring network interfaces... [ OK ]

Search Results

Search found 4509 results on 181 pages for 'logical domains'.

Page 165/181 | < Previous Page | 161 162 163 164 165 166 167 168 169 170 171 172 | Next Page >

- by pinaldave

- by Jonathan Dickinson

- by Michael Snow

- by simonsabin

- by Pinal Dave

- by rajbk

- by hamsun

- by jean-pierre.dijcks

- by MightyZot

- by ola karlsson

- by pinaldave

- by pinaldave

- by james.bayer

- by Stacy Vicknair

- by Your DisplayName here!

- by Eliah Kagan

- by David Carter

- by Omu

- by Rick Strahl

- by Paul Petrov

- by codingbloke

- by Bertrand Matthelié

- by Clint Edmonson

- by Applications User Experience

- by user69670

< Previous Page | 161 162 163 164 165 166 167 168 169 170 171 172 | Next Page >