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• Oracle @ E20 Conference Boston - Building Social Business

  - by Michael Snow

  12.00 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-family:"Calibri","sans-serif"; mso-ascii- mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi- mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Oracle WebCenter is The Engagement Platform Powering Exceptional Experiences for Employees, Partners and Customers &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;span id=&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;XinhaEditingPostion&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;/span&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;lt;p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;/p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; The way we work is changing rapidly, offering an enormous competitive advantage to those who embrace the new tools that enable contextual, agile and simplified information exchange and collaboration to distributed workforces and  networks of partners and customers. As many of you are aware, Enterprise 2.0 is the term for the technologies and business practices that liberate the workforce from the constraints of legacy communication and productivity tools like email. It provides business managers with access to the right information at the right time through a web of inter-connected applications, services and devices. Enterprise 2.0 makes accessible the collective intelligence of many, translating to a huge  competitive advantage in the form of increased innovation, productivity and agility.The Enterprise 2.0 Conference takes a strategic perspective, emphasizing the bigger picture implications of the technology and the exploration of what is at stake for organizations trying to change not only tools, but also culture and process. Beyond discussion of the "why", there will also be in-depth opportunities for learning the "how" that will help you bring Enterprise 2.0 to your business. You won't want to miss this opportunity to learn and hear from leading experts in the fields of technology for business, collaboration, culture change and collective intelligence.Oracle was a proud Gold sponsor of the Enterprise 2.0 Conference, taking place this past week in Boston. For those of you that weren't able to make it - we've made the Oracle Social Network Presentation session available here and have posted the slides below. 12.00 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-family:"Calibri","sans-serif"; mso-ascii- mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi- mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} 12.00 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-family:"Calibri","sans-serif"; mso-ascii- mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi- mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The following is intended to outline our general product direction. It is intended for information purposes only, and may not be incorporated into any contract. It is not a commitment to deliver any material, code, or functionality, and should not be relied upon in making purchasing decisions. The development, release, and timing of any features or functionality described for Oracle’s products remains at the sole discretion of Oracle. 12.00 Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; 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;}

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• C#: Does an IDisposable in a Halted Iterator Dispose?

  - by James Michael Hare

  If that sounds confusing, let me give you an example. Let's say you expose a method to read a database of products, and instead of returning a List<Product> you return an IEnumerable<Product> in iterator form (yield return). This accomplishes several good things: The IDataReader is not passed out of the Data Access Layer which prevents abstraction leak and resource leak potentials. You don't need to construct a full List<Product> in memory (which could be very big) if you just want to forward iterate once. If you only want to consume up to a certain point in the list, you won't incur the database cost of looking up the other items. This could give us an example like: 1: // a sample data access object class to do standard CRUD operations. 2: public class ProductDao 3: { 4: private DbProviderFactory _factory = SqlClientFactory.Instance 5:  6: // a method that would retrieve all available products 7: public IEnumerable<Product> GetAvailableProducts() 8: { 9: // must create the connection 10: using (var con = _factory.CreateConnection()) 11: { 12: con.ConnectionString = _productsConnectionString; 13: con.Open(); 14:  15: // create the command 16: using (var cmd = _factory.CreateCommand()) 17: { 18: cmd.Connection = con; 19: cmd.CommandText = _getAllProductsStoredProc; 20: cmd.CommandType = CommandType.StoredProcedure; 21:  22: // get a reader and pass back all results 23: using (var reader = cmd.ExecuteReader()) 24: { 25: while(reader.Read()) 26: { 27: yield return new Product 28: { 29: Name = reader["product_name"].ToString(), 30: ... 31: }; 32: } 33: } 34: } 35: } 36: } 37: } The database details themselves are irrelevant. I will say, though, that I'm a big fan of using the System.Data.Common classes instead of your provider specific counterparts directly (SqlCommand, OracleCommand, etc). This lets you mock your data sources easily in unit testing and also allows you to swap out your provider in one line of code. In fact, one of the shared components I'm most proud of implementing was our group's DatabaseUtility library that simplifies all the database access above into one line of code in a thread-safe and provider-neutral way. I went with my own flavor instead of the EL due to the fact I didn't want to force internal company consumers to use the EL if they didn't want to, and it made it easy to allow them to mock their database for unit testing by providing a MockCommand, MockConnection, etc that followed the System.Data.Common model. One of these days I'll blog on that if anyone's interested. Regardless, you often have situations like the above where you are consuming and iterating through a resource that must be closed once you are finished iterating. For the reasons stated above, I didn't want to return IDataReader (that would force them to remember to Dispose it), and I didn't want to return List<Product> (that would force them to hold all products in memory) -- but the first time I wrote this, I was worried. What if you never consume the last item and exit the loop? Are the reader, command, and connection all disposed correctly? Of course, I was 99.999999% sure the creators of C# had already thought of this and taken care of it, but inspection in Reflector was difficult due to the nature of the state machines yield return generates, so I decided to try a quick example program to verify whether or not Dispose() will be called when an iterator is broken from outside the iterator itself -- i.e. before the iterator reports there are no more items. So I wrote a quick Sequencer class with a Dispose() method and an iterator for it. Yes, it is COMPLETELY contrived: 1: // A disposable sequence of int -- yes this is completely contrived... 2: internal class Sequencer : IDisposable 3: { 4: private int _i = 0; 5: private readonly object _mutex = new object(); 6:  7: // Constructs an int sequence. 8: public Sequencer(int start) 9: { 10: _i = start; 11: } 12:  13: // Gets the next integer 14: public int GetNext() 15: { 16: lock (_mutex) 17: { 18: return _i++; 19: } 20: } 21:  22: // Dispose the sequence of integers. 23: public void Dispose() 24: { 25: // force output immediately (flush the buffer) 26: Console.WriteLine("Disposed with last sequence number of {0}!", _i); 27: Console.Out.Flush(); 28: } 29: } And then I created a generator (infinite-loop iterator) that did the using block for auto-Disposal: 1: // simply defines an extension method off of an int to start a sequence 2: public static class SequencerExtensions 3: { 4: // generates an infinite sequence starting at the specified number 5: public static IEnumerable<int> GetSequence(this int starter) 6: { 7: // note the using here, will call Dispose() when block terminated. 8: using (var seq = new Sequencer(starter)) 9: { 10: // infinite loop on this generator, means must be bounded by caller! 11: while(true) 12: { 13: yield return seq.GetNext(); 14: } 15: } 16: } 17: } This is really the same conundrum as the database problem originally posed. Here we are using iteration (yield return) over a large collection (infinite sequence of integers). If we cut the sequence short by breaking iteration, will that using block exit and hence, Dispose be called? Well, let's see: 1: // The test program class 2: public class IteratorTest 3: { 4: // The main test method. 5: public static void Main() 6: { 7: Console.WriteLine("Going to consume 10 of infinite items"); 8: Console.Out.Flush(); 9:  10: foreach(var i in 0.GetSequence()) 11: { 12: // could use TakeWhile, but wanted to output right at break... 13: if(i >= 10) 14: { 15: Console.WriteLine("Breaking now!"); 16: Console.Out.Flush(); 17: break; 18: } 19:  20: Console.WriteLine(i); 21: Console.Out.Flush(); 22: } 23:  24: Console.WriteLine("Done with loop."); 25: Console.Out.Flush(); 26: } 27: } So, what do we see? Do we see the "Disposed" message from our dispose, or did the Dispose get skipped because from an "eyeball" perspective we should be locked in that infinite generator loop? Here's the results: 1: Going to consume 10 of infinite items 2: 0 3: 1 4: 2 5: 3 6: 4 7: 5 8: 6 9: 7 10: 8 11: 9 12: Breaking now! 13: Disposed with last sequence number of 11! 14: Done with loop. Yes indeed, when we break the loop, the state machine that C# generates for yield iterate exits the iteration through the using blocks and auto-disposes the IDisposable correctly. I must admit, though, the first time I wrote one, I began to wonder and that led to this test. If you've never seen iterators before (I wrote a previous entry here) the infinite loop may throw you, but you have to keep in mind it is not a linear piece of code, that every time you hit a "yield return" it cedes control back to the state machine generated for the iterator. And this state machine, I'm happy to say, is smart enough to clean up the using blocks correctly. I suspected those wily guys and gals at Microsoft engineered it well, and I wasn't disappointed. But, I've been bitten by assumptions before, so it's good to test and see. Yes, maybe you knew it would or figured it would, but isn't it nice to know? And as those campy 80s G.I. Joe cartoon public service reminders always taught us, "Knowing is half the battle...". Technorati Tags: C#,.NET

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• Try a sample: Using the counter predicate for event sampling

  - by extended_events

  Extended Events offers a rich filtering mechanism, called predicates, that allows you to reduce the number of events you collect by specifying criteria that will be applied during event collection. (You can find more information about predicates in Using SQL Server 2008 Extended Events (by Jonathan Kehayias)) By evaluating predicates early in the event firing sequence we can reduce the performance impact of collecting events by stopping event collection when the criteria are not met. You can specify predicates on both event fields and on a special object called a predicate source. Predicate sources are similar to action in that they typically are related to some type of global information available from the server. You will find that many of the actions available in Extended Events have equivalent predicate sources, but actions and predicates sources are not the same thing. Applying predicates, whether on a field or predicate source, is very similar to what you are used to in T-SQL in terms of how they work; you pick some field/source and compare it to a value, for example, session_id = 52. There is one predicate source that merits special attention though, not just for its special use, but for how the order of predicate evaluation impacts the behavior you see. I’m referring to the counter predicate source. The counter predicate source gives you a way to sample a subset of events that otherwise meet the criteria of the predicate; for example you could collect every other event, or only every tenth event. Simple CountingThe counter predicate source works by creating an in memory counter that increments every time the predicate statement is evaluated. Here is a simple example with my favorite event, sql_statement_completed, that only collects the second statement that is run. (OK, that’s not much of a sample, but this is for demonstration purposes. Here is the session definition: CREATE EVENT SESSION counter_test ON SERVERADD EVENT sqlserver.sql_statement_completed    (ACTION (sqlserver.sql_text)    WHERE package0.counter = 2)ADD TARGET package0.ring_bufferWITH (MAX_DISPATCH_LATENCY = 1 SECONDS) You can find general information about the session DDL syntax in BOL and from Pedro’s post Introduction to Extended Events. The important part here is the WHERE statement that defines that I only what the event where package0.count = 2; in other words, only the second instance of the event. Notice that I need to provide the package name along with the predicate source. You don’t need to provide the package name if you’re using event fields, only for predicate sources. Let’s say I run the following test queries: -- Run three statements to test the sessionSELECT 'This is the first statement'GOSELECT 'This is the second statement'GOSELECT 'This is the third statement';GO Once you return the event data from the ring buffer and parse the XML (see my earlier post on reading event data) you should see something like this: event_name sql_text sql_statement_completed SELECT ‘This is the second statement’ You can see that only the second statement from the test was actually collected. (Feel free to try this yourself. Check out what happens if you remove the WHERE statement from your session. Go ahead, I’ll wait.) Percentage Sampling OK, so that wasn’t particularly interesting, but you can probably see that this could be interesting, for example, lets say I need a 25% sample of the statements executed on my server for some type of QA analysis, that might be more interesting than just the second statement. All comparisons of predicates are handled using an object called a predicate comparator; the simple comparisons such as equals, greater than, etc. are mapped to the common mathematical symbols you know and love (eg. = and >), but to do the less common comparisons you will need to use the predicate comparators directly. You would probably look to the MOD operation to do this type sampling; we would too, but we don’t call it MOD, we call it divides_by_uint64. This comparator evaluates whether one number is divisible by another with no remainder. The general syntax for using a predicate comparator is pred_comp(field, value), field is always first and value is always second. So lets take a look at how the session changes to answer our new question of 25% sampling: CREATE EVENT SESSION counter_test_25 ON SERVERADD EVENT sqlserver.sql_statement_completed    (ACTION (sqlserver.sql_text)    WHERE package0.divides_by_uint64(package0.counter,4))ADD TARGET package0.ring_bufferWITH (MAX_DISPATCH_LATENCY = 1 SECONDS)GO Here I’ve replaced the simple equivalency check with the divides_by_uint64 comparator to check if the counter is evenly divisible by 4, which gives us back every fourth record. I’ll leave it as an exercise for the reader to test this session. Why order matters I indicated at the start of this post that order matters when it comes to the counter predicate – it does. Like most other predicate systems, Extended Events evaluates the predicate statement from left to right; as soon as the predicate statement is proven false we abandon evaluation of the remainder of the statement. The counter predicate source is only incremented when it is evaluated so whether or not the counter is incremented will depend on where it is in the predicate statement and whether a previous criteria made the predicate false or not. Here is a generic example: Pred1: (WHERE statement_1 AND package0.counter = 2)Pred2: (WHERE package0.counter = 2 AND statement_1) Let’s say I cause a number of events as follows and examine what happens to the counter predicate source. Iteration Statement Pred1 Counter Pred2 Counter A Not statement_1 0 1 B statement_1 1 2 C Not statement_1 1 3 D statement_1 2 4 As you can see, in the case of Pred1, statement_1 is evaluated first, when it fails (A & C) predicate evaluation is stopped and the counter is not incremented. With Pred2 the counter is evaluated first, so it is incremented on every iteration of the event and the remaining parts of the predicate are then evaluated. In this example, Pred1 would return an event for D while Pred2 would return an event for B. But wait, there is an interesting side-effect here; consider Pred2 if I had run my statements in the following order: Not statement_1 Not statement_1 statement_1 statement_1 In this case I would never get an event back from the system because the point at which counter=2, the rest of the predicate evaluates as false so the event is not returned. If you’re using the counter target for sampling and you’re not getting the expected events, or any events, check the order of the predicate criteria. As a general rule I’d suggest that the counter criteria should be the last element of your predicate statement since that will assure that your sampling rate will apply to the set of event records defined by the rest of your predicate. Aside: I’m interested in hearing about uses for putting the counter predicate criteria earlier in the predicate statement. If you have one, post it in a comment to share with the class. - Mike Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• SQL SERVER – Weekly Series – Memory Lane – #052

  - by Pinal Dave

  Let us continue with the final episode of the Memory Lane Series. Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 Set Server Level FILLFACTOR Using T-SQL Script Specifies a percentage that indicates how full the Database Engine should make the leaf level of each index page during index creation or alteration. fillfactor must be an integer value from 1 to 100. The default is 0. Limitation of Online Index Rebuld Operation Online operation means when online operations are happening in the database are in normal operational condition, the processes which are participating in online operations does not require exclusive access to the database. Get Permissions of My Username / Userlogin on Server / Database A few days ago, I was invited to one of the largest database company. I was asked to review database schema and propose changes to it. There was special username or user logic was created for me, so I can review their database. I was very much interested to know what kind of permissions I was assigned per server level and database level. I did not feel like asking Sr. DBA the question about permissions. Simple Example of WHILE Loop With CONTINUE and BREAK Keywords This question is one of those questions which is very simple and most of the users get it correct, however few users find it confusing for the first time. I have tried to explain the usage of simple WHILE loop in the first example. BREAK keyword will exit the stop the while loop and control is moved to the next statement after the while loop. CONTINUE keyword skips all the statement after its execution and control is sent to the first statement of while loop. Forced Parameterization and Simple Parameterization – T-SQL and SSMS When the PARAMETERIZATION option is set to FORCED, any literal value that appears in a SELECT, INSERT, UPDATE or DELETE statement is converted to a parameter during query compilation. When the PARAMETERIZATION database option is SET to SIMPLE, the SQL Server query optimizer may choose to parameterize the queries. 2008 Transaction and Local Variables – Swap Variables – Update All At Once Concept Summary : Transaction have no effect over memory variables. When UPDATE statement is applied over any table (physical or memory) all the updates are applied at one time together when the statement is committed. First of all I suggest that you read the article listed above about the effect of transaction on local variant. As seen there local variables are independent of any transaction effect. Simulate INNER JOIN using LEFT JOIN statement – Performance Analysis Just a day ago, while I was working with JOINs I find one interesting observation, which has prompted me to create following example. Before we continue further let me make very clear that INNER JOIN should be used where it cannot be used and simulating INNER JOIN using any other JOINs will degrade the performance. If there are scopes to convert any OUTER JOIN to INNER JOIN it should be done with priority. 2009 Introduction to Business Intelligence – Important Terms & Definitions Business intelligence (BI) is a broad category of application programs and technologies for gathering, storing, analyzing, and providing access to data from various data sources, thus providing enterprise users with reliable and timely information and analysis for improved decision making. Difference Between Candidate Keys and Primary Key Candidate Key – A Candidate Key can be any column or a combination of columns that can qualify as unique key in database. There can be multiple Candidate Keys in one table. Each Candidate Key can qualify as Primary Key. Primary Key – A Primary Key is a column or a combination of columns that uniquely identify a record. Only one Candidate Key can be Primary Key. 2010 Taking Multiple Backup of Database in Single Command – Mirrored Database Backup I recently had a very interesting experience. In one of my recent consultancy works, I was told by our client that they are going to take the backup of the database and will also a copy of it at the same time. I expressed that it was surely possible if they were going to use a mirror command. In addition, they told me that whenever they take two copies of the database, the size of the database, is always reduced. Now this was something not clear to me, I said it was not possible and so I asked them to show me the script. Corrupted Backup File and Unsuccessful Restore The CTO, who was also present at the location, got very upset with this situation. He then asked when the last successful restore test was done. As expected, the answer was NEVER.There were no successful restore tests done before. During that time, I was present and I could clearly see the stress, confusion, carelessness and anger around me. I did not appreciate the feeling and I was pretty sure that no one in there wanted the atmosphere like me. 2011 TRACEWRITE – Wait Type – Wait Related to Buffer and Resolution SQL Trace is a SQL Server database engine technology which monitors specific events generated when various actions occur in the database engine. When any event is fired it goes through various stages as well various routes. One of the routes is Trace I/O Provider, which sends data to its final destination either as a file or rowset. DATEDIFF – Accuracy of Various Dateparts If you want to have accuracy in seconds, you need to use a different approach. In the first example, the accurate method is to find the number of seconds first and then divide it by 60 to convert it in minutes. Dedicated Access Control for SQL Server Express Edition http://www.youtube.com/watch?v=1k00z82u4OI Book Signing at SQLPASS 2012 Who I Am And How I Got Here – True Story as Blog Post If there was a shortcut to success – I want to know. I learnt SQL Server hard way and I am still learning. There are so many things, I have to learn. There is not enough time to learn everything which we want to learn. I am constantly working on it every day. I welcome you to join my journey as well. Please join me in my journey to learn SQL Server – more the merrier. Vacation, Travel and Study – A New Concept Even those who have advanced degrees and went to college for years, or even decades, find studying hard.  There is a difference between studying for a career and studying for a certification.  At least to get a degree there is a variety of subjects, with labs, exams, and practice problems to make things more interesting. Order By Numeric Values Formatted as String We have a table which has a column containing alphanumeric data. The data always has first as an integer and later part as a string. The business need is to order the data based on the first part of the alphanumeric data which is an integer. Now the problem is that no matter how we use ORDER BY the result is not produced as expected. Let us understand this with an example. Resolving SQL Server Connection Errors – SQL in Sixty Seconds #030 – Video One of the most famous errors related to SQL Server is about connecting to SQL Server itself. Here is how it goes, most of the time developers have worked with SQL Server and knows pretty much every error which they face during development language. However, hardly they install fresh SQL Server. As the installation of the SQL Server is a rare occasion unless you are a DBA who is responsible for such an instance – the error faced during installations are pretty rare as well. http://www.youtube.com/watch?v=1k00z82u4OI Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Personal Development : Time, Planning , Repairs & Maintenance

  - by Rajesh Pillai

  Personal Development : Time, Planning, Repairs & Maintenance These are just my thoughts, but some you may find something interesting in it. Please think over it. We may know many things, but still we always keeps procrastinating it. I have written this as I have heard many people coming back and saying they don’t have time to do things they like. These are my thoughts buy may be useful to someone else too. Certain things in life needs periodic repairs and maintenance. To cite some examples , your CAR, your HOUSE, your personal laptop/desktop, your health etc. Likewise there are certain other things in professional life that requires repair/ maintenance /or some kind of polishing, so that you always stay on top of it. But they are not always obvious. Some of them are - Improving your communication skills - Increasing your vocabulary - Upgrading your technical skills - Pursuing your hobby - Increasing your knowledge/awareness etc… etc… And then there are certain things that we are always short of…. one is TIME. We all know TIME is one of the most precious things in life and yet we all are very miserable at managing it. Remember you can only manage it and not control it. You can only control which you own or which you create. In theory time is infinite. So, there should be abundant of it. But remember one thing, you know this, it’s not reversible. Once it has elapsed you cannot live it again. Think over it. So, how do find that golden 25th hour every day. To find the 25th hour you need to reflect back on your current daily activities. Analyze them and see where you are spending most of your time and is it really important. Even the 8 hours that you spent in the office, is it spent fruitfully. At the end of the day is the 8 precious hour that you spent was worth it. Just reflect back on your activities. Did you learn something? If yes did you make a point to NOTE IT. If you didn’t NOTED it then was the time you spent really worth it. Just ponder over it. Some calculations of your daily activities where most of the time is spent. Let’s start (in no particular order though) - Sleep (6.5 hours) [Remember you only require 6 good hours of sleep every day]. Some may thing it is 8, but it’s a myth.   o To achive 6 hours of sleep and be in good health you can practice 15 minutes of daily meditation. So effectively you can    round it to 6.5 hours. - Morning chores(2 hours) : Some may need to prepare breakfast and all other things. - Office commuting (avg. to and fro 3 hours) - Office Work (avg 9.5 hours) Total Hours: 21 hours effective time which is spent irrespective of what you do. There may be some variations here and there. Still you have 3 hours EXTRA. Where do these 3 hours go? If you can find it, then you may get that golden 25th hour out of these 3 hours. Let’s discount 2 hours for contingencies, still you have 1 hour with you. If you can’t find it then you are living a direction less life. As you can see, the 25th Hour lies within the 24 hours of the day. It’s upto each one of us to find and make use of it. Now what can you do with that 25th hour i.e. 1 hour extra of your life. Imagine the possibility. Again some calculations 1 hour daily * 30 days = 30 hours every month 30 hours pm * 12 month = 360 hours every year. 360 hours every year seems very promising. Let’s add some contingencies, say, let’s be optimistic and say 50 % contingency. Still you have 180 hours every year. That leaves with 30 minutes every day of extra time. That’s hell a lot of time, if you could manage it. These may sound like a high talk [yes, it is, unless you apply these simple rules and rationalize your everyday living and stop procrastinating]. NOTE: I haven’t taken weekend, holidays and leaves into account. So, that leaves us with a lot of buffer time. You can meet family friends, relatives, other tasks, and yet have these 180 pure hours of joy every year. Do whatever you want to do with it. So, how important is this 180 hours per year to you? Just think over it. You may use it the way you like - 50 hours [pursue your hobby like drawing, crafting, learn dance, learn juggling, learn swimming, travelling hmm.. anything you like doing and you didn’t had time to do it.] - 30 hours you can learn a new programming language or technology (i.e. you can get comfortable with it) - 50 hours [improve existing skills] - 20 hours [improve you communication skill]. Do some light reading. - 30 hours [YOU DECIDE WHAT TO DO]? So, if you had done this for one year you would have learnt a new programming language, upgraded existing skills, improved you communication etc.. If you had done this for two years.. imagine the level of personal development or growth which you may have attained….. If you had done this for three years….. NOW I think I don’t need to mention this… So, you still have TIME, as they say TIME is infinite. So, make judicious use of this precious thing. And never ever comeback saying “I don’t have time”. So, if you are RICH in TIME, everything else will be automatically taken care of, as those things may just be a byproduct of how you spend your time… So, happy TIMING your TIME everyday.

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• Is RTD Stateless or Stateful?

  - by [email protected]

  Yes.   A stateless service is one where each request is an independent transaction that can be processed by any of the servers in a cluster.  A stateful service is one where state is kept in a server's memory from transaction to transaction, thus necessitating the proper routing of requests to the right server. The main advantage of stateless systems is simplicity of design. The main advantage of stateful systems is performance. I'm often asked whether RTD is a stateless or stateful service, so I wanted to clarify this issue in depth so that RTD's architecture will be properly understood. The short answer is: "RTD can be configured as a stateless or stateful service." The performance difference between stateless and stateful systems can be very significant, and while in a call center implementation it may be reasonable to use a pure stateless configuration, a web implementation that produces thousands of requests per second is practically impossible with a stateless configuration. RTD's performance is orders of magnitude better than most competing systems. RTD was architected from the ground up to achieve this performance. Features like automatic and dynamic compression of prediction models, automatic translation of metadata to machine code, lack of interpreted languages, and separation of model building from decisioning contribute to achieving this performance level. Because  of this focus on performance we decided to have RTD's default configuration work in a stateful manner. By being stateful RTD requests are typically handled in a few milliseconds when repeated requests come to the same session. Now, those readers that have participated in implementations of RTD know that RTD's architecture is also focused on reducing Total Cost of Ownership (TCO) with features like automatic model building, automatic time windows, automatic maintenance of database tables, automatic evaluation of data mining models, automatic management of models partitioned by channel, geography, etcetera, and hot swapping of configurations. How do you reconcile the need for a low TCO and the need for performance? How do you get the performance of a stateful system with the simplicity of a stateless system? The answer is that you make the system behave like a stateless system to the exterior, but you let it automatically take advantage of situations where being stateful is better. For example, one of the advantages of stateless systems is that you can route a message to any server in a cluster, without worrying about sending it to the same server that was handling the session in previous messages. With an RTD stateful configuration you can still route the message to any server in the cluster, so from the point of view of the configuration of other systems, it is the same as a stateless service. The difference though comes in performance, because if the message arrives to the right server, RTD can serve it without any external access to the session's state, thus tremendously reducing processing time. In typical implementations it is not rare to have high percentages of messages routed directly to the right server, while those that are not, are easily handled by forwarding the messages to the right server. This architecture usually provides the best of both worlds with performance and simplicity of configuration.   Configuring RTD as a pure stateless service A pure stateless configuration requires session data to be persisted at the end of handling each and every message and reloading that data at the beginning of handling any new message. This is of course, the root of the inefficiency of these configurations. This is also the reason why many "stateless" implementations actually do keep state to take advantage of a request coming back to the same server. Nevertheless, if the implementation requires a pure stateless decision service, this is easy to configure in RTD. The way to do it is: Mark every Integration Point to Close the session at the end of processing the message In the Session entity persist the session data on closing the session In the session entity check if a persisted version exists and load it An excellent solution for persisting the session data is Oracle Coherence, which provides a high performance, distributed cache that minimizes the performance impact of persisting and reloading the session. Alternatively, the session can be persisted to a local database. An interesting feature of the RTD stateless configuration is that it can cope with serializing concurrent requests for the same session. For example, if a web page produces two requests to the decision service, these requests could come concurrently to the decision services and be handled by different servers. Most stateless implementation would have the two requests step onto each other when saving the state, or fail one of the messages. When properly configured, RTD will make one message wait for the other before processing.   A Word on Context Using the context of a customer interaction typically significantly increases lift. For example, offer success in a call center could double if the context of the call is taken into account. For this reason, it is important to utilize the contextual information in decision making. To make the contextual information available throughout a session it needs to be persisted. When there is a well defined owner for the information then there is no problem because in case of a session restart, the information can be easily retrieved. If there is no official owner of the information, then RTD can be configured to persist this information.   Once again, RTD provides flexibility to ensure high performance when it is adequate to allow for some loss of state in the rare cases of server failure. For example, in a heavy use web site that serves 1000 pages per second the navigation history may be stored in the in memory session. In such sites it is typical that there is no OLTP that stores all the navigation events, therefore if an RTD server were to fail, it would be possible for the navigation to that point to be lost (note that a new session would be immediately established in one of the other servers). In most cases the loss of this navigation information would be acceptable as it would happen rarely. If it is desired to save this information, RTD would persist it every time the visitor navigates to a new page. Note that this practice is preferred whether RTD is configured in a stateless or stateful manner.  

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• NVIDIA x server - "sudo nvidia config" does not generate a working 'xorg.config'

  - by Mike

  I am over 18 hours deep on this challenge. I got to this point and am stuck. very stuck. Maybe you can figure it out? Ubuntu Version 12.04 LTS with all the updates installed. Problem: The default settings in "etc/X11/xorg.conf" that are generated by the "nvidia-xconfig" tool, do not allow the NVIDIA x server to connect to the driver in my "System Settings Additional Driver window". (that's how I understand it. Lots of information below). Symptoms of Problem "System Settings Additional Driver" window has drivers, but the nvidia x server cannot connect/utilize any of the 4 drivers. the drivers are activated, but not in use. When I go to "System Tools Administration NVIDIA x server settings" I get an error that basically tells me to create a default file to initialize the NVIDIA X server (screen shot below). This is the messages the terminal gives after running a "sudo nvidia-xconfig" command for the first time. It seems that the generated file by the tool i just ran is generating a bad/unusable file: If I run the "sudo nvidia-xconfig" command again, I wont get an error the second time. However when I reboot, the default file that is generated (etc/X11/xorg.conf) simply puts the screen resolution at 800 x 600 (or something big like that). When I try to go to NVIDIA x server settings I am greeted with the same screen as the screen shot as in symptom 2 (no option to change the resolution). If I try to go to "system settings display" there are no other resolutions to choose from. At this point I must delete the newly minted "xorg.conf" and reinstate the original in its place. Here are the contents of the "xorg.conf" that is generated first (the one missing required information): # nvidia-xconfig: X configuration file generated by nvidia-xconfig # nvidia-xconfig: version 304.88 (buildmeister@swio-display-x86-rhel47-06) Wed Mar 27 15:32:58 PDT 2013 Section "ServerLayout" Identifier "Layout0" Screen 0 "Screen0" InputDevice "Keyboard0" "CoreKeyboard" InputDevice "Mouse0" "CorePointer" EndSection Section "Files" EndSection Section "InputDevice" # generated from default Identifier "Mouse0" Driver "mouse" Option "Protocol" "auto" Option "Device" "/dev/psaux" Option "Emulate3Buttons" "no" Option "ZAxisMapping" "4 5" EndSection Section "InputDevice" # generated from default Identifier "Keyboard0" Driver "kbd" EndSection Section "Monitor" Identifier "Monitor0" VendorName "Unknown" ModelName "Unknown" HorizSync 28.0 - 33.0 VertRefresh 43.0 - 72.0 Option "DPMS" EndSection Section "Device" Identifier "Device0" Driver "nvidia" VendorName "NVIDIA Corporation" EndSection Section "Screen" Identifier "Screen0" Device "Device0" Monitor "Monitor0" DefaultDepth 24 SubSection "Display" Depth 24 EndSubSection EndSection Hardware: I ran the "lspci|grep VGA". There results are: 00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) 01:00.0 VGA compatible controller: NVIDIA Corporation GF108 [Quadro 1000M] (rev a1) More Hardware info: Ram: 16GB CPU: Intel Core i7-2720QM @2.2GHz * 8 Other: 64 bit. This is a triple boot computer and not a VM. Attempts With Not Success on My End: 1) Tried to append the "xorg.conf" with what I perceive is missing information and obviously it didn't fly. 2) All the other stuff I tried got me to this point. 3) See if this link is helpful to you (I barely get it, but i get enough knowing that a smarter person might find this useful): http://manpages.ubuntu.com/manpages/lucid/man1/nvidia-xconfig.1.html 4) I am completely new to Linux (40 hours over past week), but not to programming. However I am very serious about changing over to Linux. When you respond (I hope someone responds...) please respond in a way that a person new to Linux can understand. 5) By the way, the reason I am in this mess is because I MUST have a second monitor running from my laptop, and "System Settings Display" doesn't recognize my second display. I know it is possible to make the second display work in my system, because when I boot from the install CD, I perform work on the native laptop monitor, but the second monitor shows a purple screen with Ubuntu in the middle, so I know the VGA port is sending a signal out. If this is too much for you to tackle please suggest an alternative method to get a second display. I don't want to go to windows but I cannot have a single display. I am really fudged here. I hope some smart person can help. Thanks in advance. Mike. **********************EDIT #1********************** More Details About Graphics Card I was asked "which brand of nvidia-card do you have exactly?" Here is what I did to provide more info (maybe relevant, maybe not, but here is everything): 1) Took my Lenovo W520 right apart to see if there is an identifier on the actual card. However I realized that if I get deep enough to take a look, the laptop "won't like it". so I put it back together. Figuring out the card this way is not an option for me right now. 2) (My computer is triple boot) I logged into Win7 and ran 'dxdiag' command. here is the screen shot: 3) I tried to look on the lenovo website for more details... but no luck. I took a look at my receipts and here is info form receipt: System Unit: W520 NVIDIA Quadro 1000M 2GB 4) In win7 I went to the NVIDIA website and used the option to have my card 'scanned' by a Java applet to determine the latest update for my card. I tried the same with Ubuntu but I can't get the applet to run. Here is the recommended driver from from the NVIDIA Applet for my card for Win7 (I hope this shines some light on the specifics of the card): Quadro/NVS/Tesla/GRID Desktop Driver Release R319 Version: 320.00 WHQL Release Date: 3.5.2013 5) Also I went on the NVIDIA driver search and looked through every possible combination of product type + product series + product to find all the combinations that yield a 1000M card. My card is: Product Type: Quadro Product Series: Quadro Series (Notebooks) Product: 1000M ***********************EDIT #2******************* Additional Symptoms Another question that generated more symptoms I previously didn't mention was: "After generating xorg.conf by nvidia-xconfig, go to additional drivers, do you see nvidia-304?" 1) I took a screen shot of the "additional drivers" right after generating xorg.conf by nvidia-xconfig. Here it is: 2) Then I did a reboot. Now Ubuntu is 600 x 800 resolution. When I logged in after the computer came up I got an error (which I always get after generating xorg.conf by nvidia-xconfig and rebooting) 3) To finally answer the question - No. There is no "NVIDIA-304" driver. Screen shot of additional drivers after generating xorg.conf by nvidia-xconfig and rebooting : At this point I revert to the original xorg.conf and delete the xorg.conf generated by Nvidia.

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• SQL SERVER – Weekly Series – Memory Lane – #034

  - by Pinal Dave

  Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 UDF – User Defined Function to Strip HTML – Parse HTML – No Regular Expression The UDF used in the blog does fantastic task – it scans entire HTML text and removes all the HTML tags. It keeps only valid text data without HTML task. This is one of the quite commonly requested tasks many developers have to face everyday. De-fragmentation of Database at Operating System to Improve Performance Operating system skips MDF file while defragging the entire filesystem of the operating system. It is absolutely fine and there is no impact of the same on performance. Read the entire blog post for my conversation with our network engineers. Delay Function – WAITFOR clause – Delay Execution of Commands How do you delay execution of the commands in SQL Server – ofcourse by using WAITFOR keyword. In this blog post, I explain the same with the help of T-SQL script. Find Length of Text Field To measure the length of TEXT fields the function is DATALENGTH(textfield). Len will not work for text field. As of SQL Server 2005, developers should migrate all the text fields to VARCHAR(MAX) as that is the way forward. Retrieve Current Date Time in SQL Server CURRENT_TIMESTAMP, GETDATE(), {fn NOW()} There are three ways to retrieve the current datetime in SQL SERVER. CURRENT_TIMESTAMP, GETDATE(), {fn NOW()} Explanation and Comparison of NULLIF and ISNULL An interesting observation is NULLIF returns null if it comparison is successful, whereas ISNULL returns not null if its comparison is successful. In one way they are opposite to each other. Here is my question to you - How to create infinite loop using NULLIF and ISNULL? If this is even possible? 2008 Introduction to SERVERPROPERTY and example SERVERPROPERTY is a very interesting system function. It returns many of the system values. I use it very frequently to get different server values like Server Collation, Server Name etc. SQL Server Start Time We can use DMV to find out what is the start time of SQL Server in 2008 and later version. In this blog you can see how you can do the same. Find Current Identity of Table Many times we need to know what is the current identity of the column. I have found one of my developers using aggregated function MAX () to find the current identity. However, I prefer following DBCC command to figure out current identity. Create Check Constraint on Column Some time we just need to create a simple constraint over the table but I have noticed that developers do many different things to make table column follow rules than just creating constraint. I suggest constraint is a very useful concept and every SQL Developer should pay good attention to this subject. 2009 List Schema Name and Table Name for Database This is one of the blog post where I straight forward display script. One of the kind of blog posts, which I still love to read and write. Clustered Index on Separate Drive From Table Location A table devoid of primary key index is called heap, and here data is not arranged in a particular order, which gives rise to issues that adversely affect performance. Data must be stored in some kind of order. If we put clustered index on it then the order will be forced by that index and the data will be stored in that particular order. Understanding Table Hints with Examples Hints are options and strong suggestions specified for enforcement by the SQL Server query processor on DML statements. The hints override any execution plan the query optimizer might select for a query. 2010 Data Pages in Buffer Pool – Data Stored in Memory Cache One of my earlier year article, which I still read it many times and point developers to read it again. It is clear from the Resultset that when more than one index is used, datapages related to both or all of the indexes are stored in Memory Cache separately. TRANSACTION, DML and Schema Locks Can you create a situation where you can see Schema Lock? Well, this is a very simple question, however during the interview I notice over 50 candidates failed to come up with the scenario. In this blog post, I have demonstrated the situation where we can see the schema lock in database. 2011 Solution – Puzzle – Statistics are not updated but are Created Once In this example I have created following situation: Create Table Insert 1000 Records Check the Statistics Now insert 10 times more 10,000 indexes Check the Statistics – it will be NOT updated Auto Update Statistics and Auto Create Statistics for database is TRUE Now I have requested two things in the example 1) Why this is happening? 2) How to fix this issue? Selecting Domain from Email Address This is a straight to script blog post where I explain how to select only domain name from entire email address. Solution – Generating Zero Without using Any Numbers in T-SQL How to get zero digit without using any digit? This is indeed a very interesting question and the answer is even interesting. Try to come up with answer in next 10 minutes and if you can’t come up with the answer the blog post read this post for solution. 2012 Simple Explanation and Puzzle with SOUNDEX Function and DIFFERENCE Function In simple words - SOUNDEX converts an alphanumeric string to a four-character code to find similar-sounding words or names. DIFFERENCE function returns an integer value. The  integer returned is the number of characters in the SOUNDEX values that are the same. Read Only Files and SQL Server Management Studio (SSMS) I have come across a very interesting feature in SSMS related to “Read Only” files. I believe it is a little unknown feature as well so decided to write a blog about the same. Identifying Column Data Type of uniqueidentifier without Querying System Tables How do I know if any table has a uniqueidentifier column and what is its value without using any DMV or System Catalogues? Only information you know is the table name and you are allowed to return any kind of error if the table does not have uniqueidentifier column. Read the blog post to find the answer. Solution – User Not Able to See Any User Created Object in Tables – Security and Permissions Issue Interesting question – “When I try to connect to SQL Server, it lets me connect just fine as well let me open and explore the database. I noticed that I do not see any user created instances but when my colleague attempts to connect to the server, he is able to explore the database as well see all the user created tables and other objects. Can you help me fix it?” Importing CSV File Into Database – SQL in Sixty Seconds #018 – Video Here is interesting small 60 second video on how to import CSV file into Database. ColumnStore Index – Batch Mode vs Row Mode Here is the logic behind when Columnstore Index uses Batch Mode and when it uses Row Mode. A batch typically represents about 1000 rows of data. Batch mode processing also uses algorithms that are optimized for the multicore CPUs and increased memory throughput. Follow up – Usage of $rowguid and $IDENTITY This is an excellent follow up blog post of my earlier blog post where I explain where to use $rowguid and $identity.  If you do not know the difference between them, this is a blog with a script example. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• My raycaster is putting out strange results, how do I fix it?

  - by JamesK89

  I'm working on a raycaster in ActionScript 3.0 for the fun of it, and as a learning experience. I've got it up and running and its displaying me output as expected however I'm getting this strange bug where rays go through corners of blocks and the edges of blocks appear through walls. Maybe somebody with more experience can point out what I'm doing wrong or maybe a fresh pair of eyes can spot a tiny bug I haven't noticed. Thank you so much for your help! Screenshots: http://i55.tinypic.com/25koebm.jpg http://i51.tinypic.com/zx5jq9.jpg Relevant code: function drawScene() { rays.graphics.clear(); rays.graphics.lineStyle(1, rgba(0x00,0x66,0x00)); var halfFov = (player.fov/2); var numRays:int = ( stage.stageWidth / COLUMN_SIZE ); var prjDist = ( stage.stageWidth / 2 ) / Math.tan(toRad( halfFov )); var angStep = ( player.fov / numRays ); for( var i:int = 0; i < numRays; i++ ) { var rAng = ( ( player.angle - halfFov ) + ( angStep * i ) ) % 360; if( rAng < 0 ) rAng += 360; var ray:Object = castRay(player.position, rAng); drawRaySlice(i*COLUMN_SIZE, prjDist, player.angle, ray); } } function drawRaySlice(sx:int, prjDist, angle, ray:Object) { if( ray.distance >= MAX_DIST ) return; var height:int = int(( TILE_SIZE / (ray.distance * Math.cos(toRad(angle-ray.angle))) ) * prjDist); if( !height ) return; var yTop = int(( stage.stageHeight / 2 ) - ( height / 2 )); if( yTop < 0 ) yTop = 0; var yBot = int(( stage.stageHeight / 2 ) + ( height / 2 )); if( yBot > stage.stageHeight ) yBot = stage.stageHeight; rays.graphics.moveTo( (ray.origin.x / TILE_SIZE) * MINI_SIZE, (ray.origin.y / TILE_SIZE) * MINI_SIZE ); rays.graphics.lineTo( (ray.hit.x / TILE_SIZE) * MINI_SIZE, (ray.hit.y / TILE_SIZE) * MINI_SIZE ); for( var x:int = 0; x < COLUMN_SIZE; x++ ) { for( var y:int = yTop; y < yBot; y++ ) { buffer.setPixel(sx+x, y, clrTable[ray.tile-1] >> ( ray.horz ? 1 : 0 )); } } } function castRay(origin:Point, angle):Object { // Return values var rTexel = 0; var rHorz = false; var rTile = 0; var rDist = MAX_DIST + 1; var rMap:Point = new Point(); var rHit:Point = new Point(); // Ray angle and slope var ra = toRad(angle) % ANGLE_360; if( ra < ANGLE_0 ) ra += ANGLE_360; var rs = Math.tan(ra); var rUp = ( ra > ANGLE_0 && ra < ANGLE_180 ); var rRight = ( ra < ANGLE_90 || ra > ANGLE_270 ); // Ray position var rx = 0; var ry = 0; // Ray step values var xa = 0; var ya = 0; // Ray position, in map coordinates var mx:int = 0; var my:int = 0; var mt:int = 0; // Distance var dx = 0; var dy = 0; var ds = MAX_DIST + 1; // Horizontal intersection if( ra != ANGLE_180 && ra != ANGLE_0 && ra != ANGLE_360 ) { ya = ( rUp ? TILE_SIZE : -TILE_SIZE ); xa = ya / rs; ry = int( origin.y / TILE_SIZE ) * ( TILE_SIZE ) + ( rUp ? TILE_SIZE : -1 ); rx = origin.x + ( ry - origin.y ) / rs; mx = 0; my = 0; while( mx >= 0 && my >= 0 && mx < world.size.x && my < world.size.y ) { mx = int( rx / TILE_SIZE ); my = int( ry / TILE_SIZE ); mt = getMapTile(mx,my); if( mt > 0 && mt < 9 ) { dx = rx - origin.x; dy = ry - origin.y; ds = ( dx * dx ) + ( dy * dy ); if( rDist >= MAX_DIST || ds < rDist ) { rDist = ds; rTile = mt; rMap.x = mx; rMap.y = my; rHit.x = rx; rHit.y = ry; rHorz = true; rTexel = int(rx % TILE_SIZE) } break; } rx += xa; ry += ya; } } // Vertical intersection if( ra != ANGLE_90 && ra != ANGLE_270 ) { xa = ( rRight ? TILE_SIZE : -TILE_SIZE ); ya = xa * rs; rx = int( origin.x / TILE_SIZE ) * ( TILE_SIZE ) + ( rRight ? TILE_SIZE : -1 ); ry = origin.y + ( rx - origin.x ) * rs; mx = 0; my = 0; while( mx >= 0 && my >= 0 && mx < world.size.x && my < world.size.y ) { mx = int( rx / TILE_SIZE ); my = int( ry / TILE_SIZE ); mt = getMapTile(mx,my); if( mt > 0 && mt < 9 ) { dx = rx - origin.x; dy = ry - origin.y; ds = ( dx * dx ) + ( dy * dy ); if( rDist >= MAX_DIST || ds < rDist ) { rDist = ds; rTile = mt; rMap.x = mx; rMap.y = my; rHit.x = rx; rHit.y = ry; rHorz = false; rTexel = int(ry % TILE_SIZE); } break; } rx += xa; ry += ya; } } return { angle: angle, distance: Math.sqrt(rDist), hit: rHit, map: rMap, tile: rTile, horz: rHorz, origin: origin, texel: rTexel }; }

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• Fraud Detection with the SQL Server Suite Part 2

  - by Dejan Sarka

  This is the second part of the fraud detection whitepaper. You can find the first part in my previous blog post about this topic. My Approach to Data Mining Projects It is impossible to evaluate the time and money needed for a complete fraud detection infrastructure in advance. Personally, I do not know the customer’s data in advance. I don’t know whether there is already an existing infrastructure, like a data warehouse, in place, or whether we would need to build one from scratch. Therefore, I always suggest to start with a proof-of-concept (POC) project. A POC takes something between 5 and 10 working days, and involves personnel from the customer’s site – either employees or outsourced consultants. The team should include a subject matter expert (SME) and at least one information technology (IT) expert. The SME must be familiar with both the domain in question as well as the meaning of data at hand, while the IT expert should be familiar with the structure of data, how to access it, and have some programming (preferably Transact-SQL) knowledge. With more than one IT expert the most time consuming work, namely data preparation and overview, can be completed sooner. I assume that the relevant data is already extracted and available at the very beginning of the POC project. If a customer wants to have their people involved in the project directly and requests the transfer of knowledge, the project begins with training. I strongly advise this approach as it offers the establishment of a common background for all people involved, the understanding of how the algorithms work and the understanding of how the results should be interpreted, a way of becoming familiar with the SQL Server suite, and more. Once the data has been extracted, the customer’s SME (i.e. the analyst), and the IT expert assigned to the project will learn how to prepare the data in an efficient manner. Together with me, knowledge and expertise allow us to focus immediately on the most interesting attributes and identify any additional, calculated, ones soon after. By employing our programming knowledge, we can, for example, prepare tens of derived variables, detect outliers, identify the relationships between pairs of input variables, and more, in only two or three days, depending on the quantity and the quality of input data. I favor the customer’s decision of assigning additional personnel to the project. For example, I actually prefer to work with two teams simultaneously. I demonstrate and explain the subject matter by applying techniques directly on the data managed by each team, and then both teams continue to work on the data overview and data preparation under our supervision. I explain to the teams what kind of results we expect, the reasons why they are needed, and how to achieve them. Afterwards we review and explain the results, and continue with new instructions, until we resolve all known problems. Simultaneously with the data preparation the data overview is performed. The logic behind this task is the same – again I show to the teams involved the expected results, how to achieve them and what they mean. This is also done in multiple cycles as is the case with data preparation, because, quite frankly, both tasks are completely interleaved. A specific objective of the data overview is of principal importance – it is represented by a simple star schema and a simple OLAP cube that will first of all simplify data discovery and interpretation of the results, and will also prove useful in the following tasks. The presence of the customer’s SME is the key to resolving possible issues with the actual meaning of the data. We can always replace the IT part of the team with another database developer; however, we cannot conduct this kind of a project without the customer’s SME. After the data preparation and when the data overview is available, we begin the scientific part of the project. I assist the team in developing a variety of models, and in interpreting the results. The results are presented graphically, in an intuitive way. While it is possible to interpret the results on the fly, a much more appropriate alternative is possible if the initial training was also performed, because it allows the customer’s personnel to interpret the results by themselves, with only some guidance from me. The models are evaluated immediately by using several different techniques. One of the techniques includes evaluation over time, where we use an OLAP cube. After evaluating the models, we select the most appropriate model to be deployed for a production test; this allows the team to understand the deployment process. There are many possibilities of deploying data mining models into production; at the POC stage, we select the one that can be completed quickly. Typically, this means that we add the mining model as an additional dimension to an existing DW or OLAP cube, or to the OLAP cube developed during the data overview phase. Finally, we spend some time presenting the results of the POC project to the stakeholders and managers. Even from a POC, the customer will receive lots of benefits, all at the sole risk of spending money and time for a single 5 to 10 day project: The customer learns the basic patterns of frauds and fraud detection The customer learns how to do the entire cycle with their own people, only relying on me for the most complex problems The customer’s analysts learn how to perform much more in-depth analyses than they ever thought possible The customer’s IT experts learn how to perform data extraction and preparation much more efficiently than they did before All of the attendees of this training learn how to use their own creativity to implement further improvements of the process and procedures, even after the solution has been deployed to production The POC output for a smaller company or for a subsidiary of a larger company can actually be considered a finished, production-ready solution It is possible to utilize the results of the POC project at subsidiary level, as a finished POC project for the entire enterprise Typically, the project results in several important “side effects” Improved data quality Improved employee job satisfaction, as they are able to proactively contribute to the central knowledge about fraud patterns in the organization Because eventually more minds get to be involved in the enterprise, the company should expect more and better fraud detection patterns After the POC project is completed as described above, the actual project would not need months of engagement from my side. This is possible due to our preference to transfer the knowledge onto the customer’s employees: typically, the customer will use the results of the POC project for some time, and only engage me again to complete the project, or to ask for additional expertise if the complexity of the problem increases significantly. I usually expect to perform the following tasks: Establish the final infrastructure to measure the efficiency of the deployed models Deploy the models in additional scenarios Through reports By including Data Mining Extensions (DMX) queries in OLTP applications to support real-time early warnings Include data mining models as dimensions in OLAP cubes, if this was not done already during the POC project Create smart ETL applications that divert suspicious data for immediate or later inspection I would also offer to investigate how the outcome could be transferred automatically to the central system; for instance, if the POC project was performed in a subsidiary whereas a central system is available as well Of course, for the actual project, I would repeat the data and model preparation as needed It is virtually impossible to tell in advance how much time the deployment would take, before we decide together with customer what exactly the deployment process should cover. Without considering the deployment part, and with the POC project conducted as suggested above (including the transfer of knowledge), the actual project should still only take additional 5 to 10 days. The approximate timeline for the POC project is, as follows: 1-2 days of training 2-3 days for data preparation and data overview 2 days for creating and evaluating the models 1 day for initial preparation of the continuous learning infrastructure 1 day for presentation of the results and discussion of further actions Quite frequently I receive the following question: are we going to find the best possible model during the POC project, or during the actual project? My answer is always quite simple: I do not know. Maybe, if we would spend just one hour more for data preparation, or create just one more model, we could get better patterns and predictions. However, we simply must stop somewhere, and the best possible way to do this, according to my experience, is to restrict the time spent on the project in advance, after an agreement with the customer. You must also never forget that, because we build the complete learning infrastructure and transfer the knowledge, the customer will be capable of doing further investigations independently and improve the models and predictions over time without the need for a constant engagement with me.

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• Given an XML which contains a representation of a graph, how to apply it DFS algorithm? [on hold]

  - by winston smith

  Given the followin XML which is a directed graph: <?xml version="1.0" encoding="iso-8859-1" ?> <!DOCTYPE graph PUBLIC "-//FC//DTD red//EN" "../dtd/graph.dtd"> <graph direct="1"> <vertex label="V0"/> <vertex label="V1"/> <vertex label="V2"/> <vertex label="V3"/> <vertex label="V4"/> <vertex label="V5"/> <edge source="V0" target="V1" weight="1"/> <edge source="V0" target="V4" weight="1"/> <edge source="V5" target="V2" weight="1"/> <edge source="V5" target="V4" weight="1"/> <edge source="V1" target="V2" weight="1"/> <edge source="V1" target="V3" weight="1"/> <edge source="V1" target="V4" weight="1"/> <edge source="V2" target="V3" weight="1"/> </graph> With this classes i parsed the graph and give it an adjacency list representation: import java.io.IOException; import java.util.HashSet; import java.util.LinkedList; import java.util.Collection; import java.util.Iterator; import java.util.logging.Level; import java.util.logging.Logger; import practica3.util.Disc; public class ParsingXML { public static void main(String[] args) { try { // TODO code application logic here Collection<Vertex> sources = new HashSet<Vertex>(); LinkedList<String> lines = Disc.readFile("xml/directed.xml"); for (String lin : lines) { int i = Disc.find(lin, "source=\""); String data = ""; if (i > 0 && i < lin.length()) { while (lin.charAt(i + 1) != '"') { data += lin.charAt(i + 1); i++; } Vertex v = new Vertex(); v.setName(data); v.setAdy(new HashSet<Vertex>()); sources.add(v); } } Iterator it = sources.iterator(); while (it.hasNext()) { Vertex ver = (Vertex) it.next(); Collection<Vertex> adyacencias = ver.getAdy(); LinkedList<String> ls = Disc.readFile("xml/graphs.xml"); for (String lin : ls) { int i = Disc.find(lin, "target=\""); String data = ""; if (lin.contains("source=\""+ver.getName())) { Vertex v = new Vertex(); if (i > 0 && i < lin.length()) { while (lin.charAt(i + 1) != '"') { data += lin.charAt(i + 1); i++; } v.setName(data); } i = Disc.find(lin, "weight=\""); data = ""; if (i > 0 && i < lin.length()) { while (lin.charAt(i + 1) != '"') { data += lin.charAt(i + 1); i++; } v.setWeight(Integer.parseInt(data)); } if (v.getName() != null) { adyacencias.add(v); } } } } for (Vertex vert : sources) { System.out.println(vert); System.out.println("adyacencias: " + vert.getAdy()); } } catch (IOException ex) { Logger.getLogger(ParsingXML.class.getName()).log(Level.SEVERE, null, ex); } } } This is another class: import java.util.Collection; import java.util.Objects; public class Vertex { private String name; private int weight; private Collection ady; public Collection getAdy() { return ady; } public void setAdy(Collection adyacencias) { this.ady = adyacencias; } public String getName() { return name; } public void setName(String nombre) { this.name = nombre; } public int getWeight() { return weight; } public void setWeight(int weight) { this.weight = weight; } @Override public int hashCode() { int hash = 7; hash = 43 * hash + Objects.hashCode(this.name); hash = 43 * hash + this.weight; return hash; } @Override public boolean equals(Object obj) { if (obj == null) { return false; } if (getClass() != obj.getClass()) { return false; } final Vertex other = (Vertex) obj; if (!Objects.equals(this.name, other.name)) { return false; } if (this.weight != other.weight) { return false; } return true; } @Override public String toString() { return "Vertice{" + "name=" + name + ", weight=" + weight + '}'; } } And finally: /** * * @author user */ /* -*-jde-*- */ /* <Disc.java> Contains the main argument*/ import java.io.*; import java.util.LinkedList; /** * Lectura y escritura de archivos en listas de cadenas * Ideal para el uso de las clases para gráficas. * * @author Peralta Santa Anna Victor Miguel * @since Julio 2011 */ public class Disc { /** * Metodo para lectura de un archivo * * @param fileName archivo que se va a leer * @return El archivo en representacion de lista de cadenas */ public static LinkedList<String> readFile(String fileName) throws IOException { BufferedReader file = new BufferedReader(new FileReader(fileName)); LinkedList<String> textlist = new LinkedList<String>(); while (file.ready()) { textlist.add(file.readLine().trim()); } file.close(); /* for(String linea:textlist){ if(linea.contains("source")){ //String generado = linea.replaceAll("<\\w+\\s+\"", ""); //System.out.println(generado); } }*/ return textlist; }//readFile public static int find(String linea,String palabra){ int i,j; boolean found = false; for(i=0,j=0;i<linea.length();i++){ if(linea.charAt(i)==palabra.charAt(j)){ j++; if(j==palabra.length()){ found = true; return i; } }else{ continue; } } if(!found){ i= -1; } return i; } /** * Metodo para la escritura de un archivo * * @param fileName archivo que se va a escribir * @param tofile la lista de cadenas que quedaran en el archivo * @param append el bit que dira si se anexa el contenido o se empieza de cero */ public static void writeFile(String fileName, LinkedList<String> tofile, boolean append) throws IOException { FileWriter file = new FileWriter(fileName, append); for (int i = 0; i < tofile.size(); i++) { file.write(tofile.get(i) + "\n"); } file.close(); }//writeFile /** * Metodo para escritura de un archivo * @param msg archivo que se va a escribir * @param tofile la cadena que quedaran en el archivo * @param append el bit que dira si se anexa el contenido o se empieza de cero */ public static void writeFile(String msg, String tofile, boolean append) throws IOException { FileWriter file = new FileWriter(msg, append); file.write(tofile); file.close(); }//writeFile }// I'm stuck on what can be the best way to given an adjacency list representation of the graph how to apply it Depth-first search algorithm. Any idea of how to aproach to complete the task?

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• Summit Time!

  - by Ajarn Mark Caldwell

  Boy, how time flies!  I can hardly believe that the 2011 PASS Summit is just one week away.  Maybe it snuck up on me because it’s a few weeks earlier than last year.  Whatever the cause, I am really looking forward to next week.  The PASS Summit is the largest SQL Server conference in the world and a fantastic networking opportunity thrown in for no additional charge.  Here are a few thoughts to help you maximize the week. Networking As Karen Lopez (blog | @DataChick) mentioned in her presentation for the Professional Development Virtual Chapter just a couple of weeks ago, “Don’t wait until you need a new job to start networking.”  You should always be working on your professional network.  Some people, especially technical-minded people, get confused by the term networking.  The first image that used to pop into my head was the image of some guy standing, awkwardly, off to the side of a cocktail party, trying to shmooze those around him.  That’s not what I’m talking about.  If you’re good at that sort of thing, and you can strike up a conversation with some stranger and learn all about them in 5 minutes, and walk away with your next business deal all but approved by the lawyers, then congratulations.  But if you’re not, and most of us are not, I have two suggestions for you.  First, register for Don Gabor’s 2-hour session on Tuesday at the Summit called Networking to Build Business Contacts.  Don is a master at small talk, and at teaching others, and in just those two short hours will help you with important tips about breaking the ice, remembering names, and smooth transitions into and out of conversations.  Then go put that great training to work right away at the Tuesday night Welcome Reception and meet some new people; which is really my second suggestion…just meet a few new people.  You see, “networking” is about meeting new people and being friendly without trying to “work it” to get something out of the relationship at this point.  In fact, Don will tell you that a better way to build the connection with someone is to look for some way that you can help them, not how they can help you. There are a ton of opportunities as long as you follow this one key point: Don’t stay in your hotel!  At the least, get out and go to the free events such as the Tuesday night Welcome Reception, the Wednesday night Exhibitor Reception, and the Thursday night Community Appreciation Party.  All three of these are perfect opportunities to meet other professionals with a similar job or interest as you, and you never know how that may help you out in the future.  Maybe you just meet someone to say HI to at breakfast the next day instead of eating alone.  Or maybe you cross paths several times throughout the Summit and compare notes on different sessions you attended.  And you just might make new friends that you look forward to seeing year after year at the Summit.  Who knows, it might even turn out that you have some specific experience that will help out that other person a few months’ from now when they run into the same challenge that you just overcame, or vice-versa.  But the point is, if you don’t get out and meet people, you’ll never have the chance for anything else to happen in the future. One more tip for shy attendees of the Summit…if you can’t bring yourself to strike up conversation with strangers at these events, then at the least, after you sit through a good session that helps you out, go up to the speaker and introduce yourself and thank them for taking the time and effort to put together their presentation.  Ideally, when you do this, tell them WHY it was beneficial to you (e.g. “Now I have a new idea of how to tackle a problem back at the office.”)  I know you think the speakers are all full of confidence and are always receiving a ton of accolades and applause, but you’re wrong.  Most of them will be very happy to hear first-hand that all the work they put into getting ready for their presentation is paying off for somebody. Training With over 170 technical sessions at the Summit, training is what it’s all about, and the training is fantastic!  Of course there are the big-name trainers like Paul Randall, Kimberly Tripp, Kalen Delaney, Itzik Ben-Gan and several others, but I am always impressed by the quality of the training put on by so many other “regular” members of the SQL Server community.  It is amazing how you don’t have to be a published author or otherwise recognized as an “expert” in an area in order to make a big impact on others just by sharing your personal experience and lessons learned.  I would rather hear the story of, and lessons learned from, “some guy or gal” who has actually been through an issue and came out the other side, than I would a trained professor who is speaking just from theory or an intellectual understanding of a topic. In addition to the three full days of regular sessions, there are also two days of pre-conference intensive training available.  There is an extra cost to this, but it is a fantastic opportunity.  Think about it…you’re already coming to this area for training, so why not extend your stay a little bit and get some in-depth training on a particular topic or two?  I did this for the first time last year.  I attended one day of extra training and it was well worth the time and money.  One of the best reasons for it is that I am extremely busy at home with my regular job and family, that it was hard to carve out the time to learn about the topic on my own.  It worked out so well last year that I am doubling up and doing two days or “pre-cons” this year. And then there are the DVDs.  I think these are another great option.  I used the online schedule builder to get ready and have an idea of which sessions I want to attend and when they are (much better than trying to figure this out at the last minute every day).  But the problem that I have run into (seems this happens every year) is that nearly every session block has two different sessions that I would like to attend.  And some of them have three!  ACK!  That won’t work!  What is a guy supposed to do?  Well, one option is to purchase the DVDs which are recordings of the audio and projected images from each session so you can continue to attend sessions long after the Summit is officially over.  Yes, many (possibly all) of these also get posted online and attendees can access those for no extra charge, but those are not necessarily all available as quickly as the DVD recording are, and the DVDs are often more convenient than downloading, especially if you want to share the training with someone who was not able to attend in person. Remember, I don’t make any money or get any other benefit if you buy the DVDs or from anything else that I have recommended here.  These are just my own thoughts, trying to help out based on my experiences from the 8 or so Summits I have attended.  There is nothing like the Summit.  It is an awesome experience, fantastic training, and a whole lot of fun which is just compounded if you’ll take advantage of the first part of this article and make some new friends along the way.

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• Big Visible Charts

  - by Robert May

  An important part of Agile is the concept of transparency and visibility. In proper functioning teams, stakeholders can look at any team at any time in the iteration or release and see how that team is doing by simply looking at what we call Big Visible Charts. If you’ve done Scrum, you’ve seen these charts. However, interpreting these charts can often be an art form. There are several different charts that can be useful. In this newsletter, I’ll focus on the Iteration Burndown and Cumulative Flow charts. I’ve included a copy of the spreadsheet that I used to create the charts, and if you don’t have a tool that creates them for you, you can use this spreadsheet to do so. Our preferred tool for managing Scrum projects is Rally. Rally creates all of these charts for you, saving you quite a bit of time. The Iteration Burndown and Cumulative Flow Charts This is the main chart that teams use. Although less useful to stakeholders, this chart is critical to the team and provides quite a bit of information to the team about how their iteration is going. Most charts are a combination of the charts below, so you may need to combine aspects of each section to understand what is happening in your iterations. Ideal Ah, isn’t that a pretty picture? Unfortunately, it’s also very unrealistic. I’ve seen iterations that come close to ideal, but never that match perfectly. If your iteration matches perfectly, chances are, someone is playing with the numbers. Reality is just too difficult to have a burndown chart that matches this exactly. Late Planning Iteration started, but the team didn’t. You can tell this by the fact that the real number of estimated hours didn’t appear until day two. In the cumulative flow, you can also see that nothing was defined in Day one and two. You want to avoid situations like this. You’ll note that the team had to burn faster than is ideal to meet the iteration because of the late planning. This often results in long weeks and days. Testing Starved Determining whether or not testing is starved is difficult without the cumulative flow. The pattern in the burndown could be nothing more that developers not completing stories early enough or could be caused by stories being too big. With the cumulative flow, however, you see that only small bites are in progress and stories were completed early, but testing didn’t start testing until the end of the iteration, and didn’t complete testing all stories in the iteration. When this happens, question whether or not your testing resources are sufficient for your team and whether or not acceptance is adequately defined. No Testing With this one, both graphs show the same thing; the team needs testers and testing! Without testing, what was completed cannot be verified to make sure that it is acceptable to the business. If you find yourself in this situation, review your testing practices and acceptance testing process and make changes today. Late Development With this situation, both graphs tell a story. In the top graph, you can see that the hours failed to burn down as quickly as the team expected. This could be caused by the team not correctly estimating their hours or the team could have had illness or some other issue that affected them. Often, when teams are tackling something that is more unknown, they’ll run into technical barriers that cause the burn down to happen slower than expected. In the cumulative flow graph, you can see that not much was completed in the first few days. This could be because of illness or technical barriers or simply poor estimation. Testing was able to keep up with everything that was completed, however. No Tool Updating When you see graphs that look like this, you can be assured that it’s because the team is not updating the tool that generates the graphs. Review your policy for when they are to update. On the teams that I run, I require that each team member updates the tool at least once daily. You should also check to see how well the team is breaking down stories into tasks. If they’re creating few large tasks, graphs can look similar to this. As a general rule, I never allow tasks, other than Unit Testing and Uncertainty, to be greater than eight hours in duration. Scope Increase I always encourage team members to enter in however much time they think they have left on a task, even if that means increasing the total amount of time left to do. You get a much better and more realistic picture this way. Increasing time remaining could explain the burndown graph, but by looking at the cumulative flow graph, we can see that stories were added to the iteration and scope was increased. Since planning should consume all of the hours in the iteration, this is almost always a bad thing. If the scope change happened late in the iteration and the hours remaining were well below the ideal burn, then increasing scope is probably o.k., but estimation needs to get better. However, with the charts above, that’s clearly not what happened and the team was required to do extra work to make the iteration. If you find this happening, your product owner and ScrumMasters need training. The team also needs to learn to say no. Scope Decrease Scope decreases are just as bad as scope increases. Usually, graphs above show that the team did a poor job of estimating their stories and part way through had to reduce scope to change the iteration. This will happen once in a while, but if you find it’s a pattern on your team, you need to re-evaluate planning. Some teams are hopelessly optimistic. In those cases, I’ll introduce a task I call “Uncertainty.” With Uncertainty, the team estimates how many hours they might need if things don’t go well with the tasks they’ve defined. They try to estimate things that could go poorly and increase the time appropriately. Having an Uncertainty task allows them to have a low and high estimate. Uncertainty should not just be an arbitrary buffer. It must correlate to real uncertainty in the tasks that have been defined. Stories are too Big Often, we see graphs like the ones above. Note that the burndown looks fairly good, other than the chunky acceptance of stories. However, when you look at cumulative flow, you can see that at one point, everything is in progress. This is a bad thing. When you see graphs like this, you’re in one of two states. You may just have a very small team and can only handle one or two stories in your iteration. If you have more than one or two people, then the most likely problem is that your stories are far too big. To combat this, break large high hour stories into smaller pieces that can be completed independently and accepted independently. If you don’t, you’ll likely be requiring your testers to do heroic things to complete testing on the last day of the iteration and you’re much more likely to have the entire iteration fail, because of the limited amount of things that can be completed. Summary There are other charts that can be useful when doing scrum. If you don’t have any big visible charts, you really need to evaluate your process and change. These charts can provide the team a wealth of information and help you write better software. If you have any questions about charts that you’re seeing on your team, contact me with a screen capture of the charts and I’ll tell you what I’m seeing in those charts. I always want this information to be useful, so please let me know if you have other questions. Technorati Tags: Agile

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• How to select the first ocurrence in the auto-completion menu by pressing Enter?

  - by janoChen

  Every time there's is a pop up menu. I select the first occurrence and press enter but nothing happens (the word is not completed with he selected occurrence). The only way is to press Tab until you reach the term for a second time. Is there a way of selecting the first occurrence pressing Enter (or other Vim hotkey)? My .vimrc: " SHORTCUTS nnoremap <F4> :set filetype=html<CR> nnoremap <F5> :set filetype=php<CR> nnoremap <F3> :TlistToggle<CR> " press space to turn off highlighting and clear any message already displayed. nnoremap <silent> <Space> :nohlsearch<Bar>:echo<CR> " set buffers commands nnoremap <silent> <M-F8> :BufExplorer<CR> nnoremap <silent> <F8> :bn<CR> nnoremap <silent> <S-F8> :bp<CR> " open NERDTree with start directory: D:\wamp\www nnoremap <F9> :NERDTree /home/alex/www<CR> " open MRU nnoremap <F10> :MRU<CR> " open current file (silently) nnoremap <silent> <F11> :let old_reg=@"<CR>:let @"=substitute(expand("%:p"), "/", "\\", "g")<CR>:silent!!cmd /cstart <C-R><C-R>"<CR><CR>:let @"=old_reg<CR> " open current file in localhost (default browser) nnoremap <F12> :! start "http://localhost" file:///"%:p""<CR> " open Vim's default Explorer nnoremap <silent> <F2> :Explore<CR> nnoremap <C-F2> :%s/\.html/.php/g<CR> " REMAPPING " map leader to , let mapleader = "," " remap ` to ' nnoremap ' ` nnoremap ` ' " remap increment numbers nnoremap <C-kPlus> <C-A> " COMPRESSION function Js_css_compress () let cwd = expand('<afile>:p:h') let nam = expand('<afile>:t:r') let ext = expand('<afile>:e') if -1 == match(nam, "[\._]src$") let minfname = nam.".min.".ext else let minfname = substitute(nam, "[\._]src$", "", "g").".".ext endif if ext == 'less' if executable('lessc') cal system( 'lessc '.cwd.'/'.nam.'.'.ext.' &') endif else if filewritable(cwd.'/'.minfname) if ext == 'js' && executable('closure-compiler') cal system( 'closure-compiler --js '.cwd.'/'.nam.'.'.ext.' > '.cwd.'/'.minfname.' &') elseif executable('yuicompressor') cal system( 'yuicompressor '.cwd.'/'.nam.'.'.ext.' > '.cwd.'/'.minfname.' &') endif endif endif endfunction autocmd FileWritePost,BufWritePost *.js :call Js_css_compress() autocmd FileWritePost,BufWritePost *.css :call Js_css_compress() autocmd FileWritePost,BufWritePost *.less :call Js_css_compress() " GUI " taglist right side let Tlist_Use_Right_Window = 1 " hide tool bar set guioptions-=T "remove scroll bars set guioptions+=LlRrb set guioptions-=LlRrb " set the initial size of window set lines=46 columns=180 " set default font set guifont=Monospace " set guifont=Monospace\ 10 " show line number set number " set default theme colorscheme molokai-2 " encoding set encoding=utf-8 setglobal fileencoding=utf-8 bomb set fileencodings=ucs-bom,utf-8,latin1 " SCSS syntax highlight au BufRead,BufNewFile *.scss set filetype=scss " LESS syntax highlight syntax on au BufNewFile,BufRead *.less set filetype=less " Haml syntax highlight "au! BufRead,BufNewFile *.haml "setfiletype haml " Sass syntax highlight "au! BufRead,BufNewFile *.sass "setfiletype sass " set filetype indent filetype indent on " for snipMate to work filetype plugin on " show breaks set showbreak=-----> " coding format set tabstop=4 set shiftwidth=4 set linespace=1 " CONFIG " set location of ctags let Tlist_Ctags_Cmd='D:\ctags58\ctags.exe' " keep the buffer around when left set hidden " enable matchit plugin source $VIMRUNTIME/macros/matchit.vim " folding set foldmethod=marker set foldmarker={,} let g:FoldMethod = 0 map <leader>ff :call ToggleFold()<cr> fun! ToggleFold() if g:FoldMethod == 0 exe 'set foldmethod=indent' let g:FoldMethod = 1 else exe 'set foldmethod=marker' let g:FoldMethod = 0 endif endfun " save and restore folds when a file is closed and re-opened "au BufWrite ?* mkview "au BufRead ?* silent loadview " auto-open NERDTree everytime Vim is invoked au VimEnter * NERDTree /home/alex/www " set omnicomplete autocmd FileType python set omnifunc=pythoncomplete#Complete autocmd FileType javascript set omnifunc=javascriptcomplete#CompleteJS autocmd FileType html set omnifunc=htmlcomplete#CompleteTags autocmd FileType css set omnifunc=csscomplete#CompleteCSS autocmd FileType xml set omnifunc=xmlcomplete#CompleteTags autocmd FileType php set omnifunc=phpcomplete#CompletePHP autocmd FileType c set omnifunc=ccomplete#Complete " Remove trailing white-space once the file is saved au BufWritePre * silent g/\s\+$/s/// " Use CTRL-S for saving, also in Insert mode noremap <C-S> :update!<CR> vnoremap <C-S> <C-C>:update!<CR> inoremap <C-S> <C-O>:update!<CR> " DEFAULT set nocompatible source $VIMRUNTIME/vimrc_example.vim "source $VIMRUNTIME/mswin.vim "behave mswin " disable creation of swap files set noswapfile " no back ups wwhile editing set nowritebackup " disable creation of backups set nobackup " no file change pop up warning autocmd FileChangedShell * echohl WarningMsg | echo "File changed shell." | echohl None set diffexpr=MyDiff() function MyDiff() let opt = '-a --binary ' if &diffopt =~ 'icase' | let opt = opt . '-i ' | endif if &diffopt =~ 'iwhite' | let opt = opt . '-b ' | endif let arg1 = v:fname_in if arg1 =~ ' ' | let arg1 = '"' . arg1 . '"' | endif let arg2 = v:fname_new if arg2 =~ ' ' | let arg2 = '"' . arg2 . '"' | endif let arg3 = v:fname_out if arg3 =~ ' ' | let arg3 = '"' . arg3 . '"' | endif let eq = '' if $VIMRUNTIME =~ ' ' if &sh =~ '\<cmd' let cmd = '""' . $VIMRUNTIME . '\diff"' let eq = '"' else let cmd = substitute($VIMRUNTIME, ' ', '" ', '') . '\diff"' endif else let cmd = $VIMRUNTIME . '\diff' endif silent execute '!' . cmd . ' ' . opt . arg1 . ' ' . arg2 . ' > ' . arg3 . eq endfunction

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• Unable to boot Ubuntu 13.10 (nVidia GTX 770m and Intel HD 4600)

  - by Raziel Gonzalez

  Ever since I bought this laptop I've been trying to install Ubuntu on it. It came with W8 preinstalled. Up to this point, I've been able to boot in UEFI mode with a black screen. I can tell it's trying to use the nVidia card (there's a led on the computer, depending on the color you can tell which GPU is using) and if I press crtl+alt+F1 I can go to console mode. Taking this advantage I tried to install bumblebee and after a successful install the led that indicates which GPU is being used change, indicating that it switched to the Intel HD 4600 graphics. After the installation I tried to initiate the graphic interface (startx) with no success. Xorg.0.log shows the error: [ 3706.779] X.Org X Server 1.14.3 Release Date: 2013-09-12 [ 3706.782] X Protocol Version 11, Revision 0 [ 3706.783] Build Operating System: Linux 3.2.0-37-generic x86_64 Ubuntu [ 3706.783] Current Operating System: Linux ubuntu 3.11.0-12-generic #19-Ubuntu SMP Wed Oct 9 16:20:46 UTC 2013 x86_64 [ 3706.783] Kernel command line: BOOT_IMAGE=/casper/vmlinuz.efi file=/cdrom/preseed/ubuntu.seed boot=casper nomodeset -- [ 3706.785] Build Date: 15 October 2013 09:23:37AM [ 3706.786] xorg-server 2:1.14.3-3ubuntu2 (For technical support please see http://www.ubuntu.com/support) [ 3706.786] Current version of pixman: 0.30.2 [ 3706.788] Before reporting problems, check http://wiki.x.org to make sure that you have the latest version. [ 3706.788] Markers: (--) probed, (**) from config file, (==) default setting, (++) from command line, (!!) notice, (II) informational, (WW) warning, (EE) error, (NI) not implemented, (??) unknown. [ 3706.791] (==) Log file: "/var/log/Xorg.0.log", Time: Sat Nov 2 12:28:52 2013 [ 3706.792] (==) Using system config directory "/usr/share/X11/xorg.conf.d" [ 3706.792] (==) No Layout section. Using the first Screen section. [ 3706.792] (==) No screen section available. Using defaults. [ 3706.792] (**) |-->Screen "Default Screen Section" (0) [ 3706.792] (**) | |-->Monitor "<default monitor>" [ 3706.792] (==) No monitor specified for screen "Default Screen Section". Using a default monitor configuration. [ 3706.792] (==) Automatically adding devices [ 3706.792] (==) Automatically enabling devices [ 3706.792] (==) Automatically adding GPU devices [ 3706.792] (WW) The directory "/usr/share/fonts/X11/cyrillic" does not exist. [ 3706.792] Entry deleted from font path. [ 3706.792] (WW) The directory "/usr/share/fonts/X11/100dpi/" does not exist. [ 3706.792] Entry deleted from font path. [ 3706.792] (WW) The directory "/usr/share/fonts/X11/75dpi/" does not exist. [ 3706.792] Entry deleted from font path. [ 3706.792] (WW) The directory "/usr/share/fonts/X11/100dpi" does not exist. [ 3706.792] Entry deleted from font path. [ 3706.792] (WW) The directory "/usr/share/fonts/X11/75dpi" does not exist. [ 3706.792] Entry deleted from font path. [ 3706.792] (==) FontPath set to: /usr/share/fonts/X11/misc, /usr/share/fonts/X11/Type1, built-ins [ 3706.792] (==) ModulePath set to "/usr/lib/x86_64-linux-gnu/xorg/extra-modules,/usr/lib/xorg/extra-modules,/usr/lib/xorg/modules" [ 3706.792] (II) The server relies on udev to provide the list of input devices. If no devices become available, reconfigure udev or disable AutoAddDevices. [ 3706.792] (II) Loader magic: 0x7ff680918d20 [ 3706.792] (II) Module ABI versions: [ 3706.792] X.Org ANSI C Emulation: 0.4 [ 3706.792] X.Org Video Driver: 14.1 [ 3706.792] X.Org XInput driver : 19.1 [ 3706.792] X.Org Server Extension : 7.0 [ 3706.793] (--) PCI:*(0:0:2:0) 8086:0416:1462:10e8 rev 6, Mem @ 0xf7400000/4194304, 0xb0000000/268435456, I/O @ 0x0000f000/64 [ 3706.793] (II) Open ACPI successful (/var/run/acpid.socket) [ 3706.794] Initializing built-in extension Generic Event Extension [ 3706.795] Initializing built-in extension SHAPE [ 3706.796] Initializing built-in extension MIT-SHM [ 3706.797] Initializing built-in extension XInputExtension [ 3706.797] Initializing built-in extension XTEST [ 3706.798] Initializing built-in extension BIG-REQUESTS [ 3706.799] Initializing built-in extension SYNC [ 3706.799] Initializing built-in extension XKEYBOARD [ 3706.800] Initializing built-in extension XC-MISC [ 3706.801] Initializing built-in extension SECURITY [ 3706.802] Initializing built-in extension XINERAMA [ 3706.802] Initializing built-in extension XFIXES [ 3706.803] Initializing built-in extension RENDER [ 3706.804] Initializing built-in extension RANDR [ 3706.804] Initializing built-in extension COMPOSITE [ 3706.805] Initializing built-in extension DAMAGE [ 3706.806] Initializing built-in extension MIT-SCREEN-SAVER [ 3706.806] Initializing built-in extension DOUBLE-BUFFER [ 3706.807] Initializing built-in extension RECORD [ 3706.807] Initializing built-in extension DPMS [ 3706.808] Initializing built-in extension X-Resource [ 3706.809] Initializing built-in extension XVideo [ 3706.809] Initializing built-in extension XVideo-MotionCompensation [ 3706.810] Initializing built-in extension SELinux [ 3706.811] Initializing built-in extension XFree86-VidModeExtension [ 3706.811] Initializing built-in extension XFree86-DGA [ 3706.812] Initializing built-in extension XFree86-DRI [ 3706.812] Initializing built-in extension DRI2 [ 3706.812] (II) "glx" will be loaded by default. [ 3706.812] (WW) "xmir" is not to be loaded by default. Skipping. [ 3706.812] (II) LoadModule: "dri2" [ 3706.812] (II) Module "dri2" already built-in [ 3706.812] (II) LoadModule: "glamoregl" [ 3706.813] (II) Loading /usr/lib/xorg/modules/libglamoregl.so [ 3706.813] (II) Module glamoregl: vendor="X.Org Foundation" [ 3706.813] compiled for 1.14.2.901, module version = 0.5.1 [ 3706.813] ABI class: X.Org ANSI C Emulation, version 0.4 [ 3706.813] (II) LoadModule: "glx" [ 3706.813] (II) Loading /usr/lib/xorg/modules/extensions/libglx.so [ 3706.813] (II) Module glx: vendor="X.Org Foundation" [ 3706.813] compiled for 1.14.3, module version = 1.0.0 [ 3706.813] ABI class: X.Org Server Extension, version 7.0 [ 3706.813] (==) AIGLX enabled [ 3706.814] Loading extension GLX [ 3706.814] (==) Matched intel as autoconfigured driver 0 [ 3706.814] (==) Matched vesa as autoconfigured driver 1 [ 3706.814] (==) Matched modesetting as autoconfigured driver 2 [ 3706.814] (==) Matched fbdev as autoconfigured driver 3 [ 3706.814] (==) Assigned the driver to the xf86ConfigLayout [ 3706.814] (II) LoadModule: "intel" [ 3706.814] (II) Loading /usr/lib/xorg/modules/drivers/intel_drv.so [ 3706.814] (II) Module intel: vendor="X.Org Foundation" [ 3706.814] compiled for 1.14.3, module version = 2.99.904 [ 3706.814] Module class: X.Org Video Driver [ 3706.814] ABI class: X.Org Video Driver, version 14.1 [ 3706.814] (II) LoadModule: "vesa" [ 3706.814] (II) Loading /usr/lib/xorg/modules/drivers/vesa_drv.so [ 3706.814] (II) Module vesa: vendor="X.Org Foundation" [ 3706.814] compiled for 1.14.1, module version = 2.3.2 [ 3706.814] Module class: X.Org Video Driver [ 3706.814] ABI class: X.Org Video Driver, version 14.1 [ 3706.814] (II) LoadModule: "modesetting" [ 3706.814] (II) Loading /usr/lib/xorg/modules/drivers/modesetting_drv.so [ 3706.814] (II) Module modesetting: vendor="X.Org Foundation" [ 3706.814] compiled for 1.14.1, module version = 0.8.0 [ 3706.814] Module class: X.Org Video Driver [ 3706.814] ABI class: X.Org Video Driver, version 14.1 [ 3706.814] (II) LoadModule: "fbdev" [ 3706.814] (II) Loading /usr/lib/xorg/modules/drivers/fbdev_drv.so [ 3706.815] (II) Module fbdev: vendor="X.Org Foundation" [ 3706.815] compiled for 1.14.1, module version = 0.4.3 [ 3706.815] Module class: X.Org Video Driver [ 3706.815] ABI class: X.Org Video Driver, version 14.1 [ 3706.815] (II) intel: Driver for Intel(R) Integrated Graphics Chipsets: i810, i810-dc100, i810e, i815, i830M, 845G, 854, 852GM/855GM, 865G, 915G, E7221 (i915), 915GM, 945G, 945GM, 945GME, Pineview GM, Pineview G, 965G, G35, 965Q, 946GZ, 965GM, 965GME/GLE, G33, Q35, Q33, GM45, 4 Series, G45/G43, Q45/Q43, G41, B43, HD Graphics, HD Graphics 2000, HD Graphics 3000, HD Graphics 2500, HD Graphics 4000, HD Graphics P4000, HD Graphics 4600, HD Graphics 5000, HD Graphics P4600/P4700, Iris(TM) Graphics 5100, HD Graphics 4400, HD Graphics 4200, Iris(TM) Pro Graphics 5200 [ 3706.815] (II) VESA: driver for VESA chipsets: vesa [ 3706.815] (II) modesetting: Driver for Modesetting Kernel Drivers: kms [ 3706.815] (II) FBDEV: driver for framebuffer: fbdev [ 3706.815] (--) using VT number 7 [ 3706.819] (WW) Falling back to old probe method for modesetting [ 3706.819] (EE) open /dev/dri/card0: No such file or directory [ 3706.819] (WW) Falling back to old probe method for fbdev [ 3706.819] (II) Loading sub module "fbdevhw" [ 3706.819] (II) LoadModule: "fbdevhw" [ 3706.819] (II) Loading /usr/lib/xorg/modules/libfbdevhw.so [ 3706.819] (II) Module fbdevhw: vendor="X.Org Foundation" [ 3706.819] compiled for 1.14.3, module version = 0.0.2 [ 3706.819] ABI class: X.Org Video Driver, version 14.1 [ 3706.819] (II) Loading sub module "vbe" [ 3706.819] (II) LoadModule: "vbe" [ 3706.819] (II) Loading /usr/lib/xorg/modules/libvbe.so [ 3706.819] (II) Module vbe: vendor="X.Org Foundation" [ 3706.819] compiled for 1.14.3, module version = 1.1.0 [ 3706.819] ABI class: X.Org Video Driver, version 14.1 [ 3706.819] (II) Loading sub module "int10" [ 3706.819] (II) LoadModule: "int10" [ 3706.819] (II) Loading /usr/lib/xorg/modules/libint10.so [ 3706.819] (II) Module int10: vendor="X.Org Foundation" [ 3706.819] compiled for 1.14.3, module version = 1.0.0 [ 3706.819] ABI class: X.Org Video Driver, version 14.1 [ 3706.819] (II) VESA(0): initializing int10 [ 3706.820] (EE) VESA(0): V_BIOS address 0x0 out of range [ 3706.820] (II) UnloadModule: "vesa" [ 3706.820] (II) UnloadSubModule: "int10" [ 3706.820] (II) Unloading int10 [ 3706.820] (II) UnloadSubModule: "vbe" [ 3706.820] (II) Unloading vbe [ 3706.820] (EE) Screen(s) found, but none have a usable configuration. [ 3706.820] (EE) Fatal server error: [ 3706.820] (EE) no screens found(EE) [ 3706.820] (EE) Please consult the The X.Org Foundation support at http://wiki.x.org for help. [ 3706.820] (EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information. [ 3706.820] (EE) [ 3706.827] (EE) Server terminated with error (1). Closing log file. I also saved the dsmeg output to see if it can be of any help. In order to be able to get to this stage I had to boot with nomodeset option and removed quiet and splash. Anyone got this same error? Any guidance? I've tried other linux distros and so far the only one that is able to boot is Opensuse 12.3 without any issues (but only when I switch to legacy mode instead of UEFI).

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• Thoughts on Build 2013

  - by D'Arcy Lussier

  Originally posted on: http://geekswithblogs.net/dlussier/archive/2013/06/30/153294.aspxAnd so another Build conference has come to an end. Below are my thoughts/perspectives on various aspects of the event. I’ll do a separate blog post on my thoughts of the Build message for developers. The Good Moscone center was a great venue for Build! Easy to get around, easy to get to, and well maintained, it was a very comfortable conference venue. Yeah, the free swag was nice. Build has built up an expectation that attendees will always get something; it’ll be interesting to see how Microsoft maintains this expectation over the next few Build events. I still maintain that free swag should never be the main reason one attends an event, and for me this was definitely just an added bonus. I’m planning on trying to use the Surface as a dedicated 2nd device at work for meetings, I’ll share my experiences over the next few months. The hackathon event was a great idea, although personally I couldn’t justify spending the money on a conference registration just to spend the entire conference coding. Still, the apps that were created were really great and there was a lot of passion and excitement around the hackathon. I wonder if they couldn’t have had the hackathon on the Monday/Tuesday for those that wanted to participate so they didn’t miss any of the actual conference over Wed/Thurs. San Francisco was a great city to host Build. Getting from hotels to the conference center was very easy (well especially for me, I was only 3 blocks away) and the city itself felt very safe. However, if I never have to fly into SFO again I’ll be alright with that! Delays going into and out of SFO and both apparently were due to the airport itself. The Bad Build is one of those oddities on the conference landscape where people will pay to commit to attending an event without knowing anything about the sessions. We got our list of conference sessions when we registered on Tuesday, not before. And even then, we only got titles and not descriptions (those were eventually made available via the conference’s mobile application). I get it…they’re going to make announcements and they don’t want to give anything away through the session titles. But honestly, there wasn’t anything in the session titles that I would have considered a surprise. Breakfasts were brutal. High-carb pastries, donuts, and muffins with fruit and hard boiled eggs does not a conference breakfast make. I can’t believe that the difference between a continental breakfast per person and a hot breakfast buffet would have been a huge impact to a conference fee that was already around $2000. The vendor area was anemic. I don’t know why Microsoft forces the vendors into cookie-cutter booth areas (this year they were all made of plywood material). WPC, TechEd – booth areas there allow the vendors to be creative with their displays. Not so much for Build. Really odd was the lack of Microsoft’s own representation around Bing. In the day 1 keynote Microsoft made a big deal about Bing as an API. Yet there was nobody in the vendor area set up to provide more information or have discussions with about the Bing API. The Ugly Our name badges were NFC enabled. The purpose of this, beyond the vendors being able to scan your info, wasn’t really made clear. An attendee I talked to showed how you could get a reader app on your phone so you can scan other members cards and collect their contact info – which is a kewl idea; business cards are so 1990’s. But I was *shocked* at the amount of information that was on our name badges! Here’s what’s displayed on our name badge: - Name - Company - Twitter Handle I’m ok with that. But here’s what actually gets read: - Name - Company - Address Used for Registration - Phone Number Used for Registration So sharing that info with another attendee, they get way more of my info than just how to find me on Twitter! Microsoft, you need to fix this for the future. If vendors want to collect information on attendees, they should be able to collect an ID from the badge, then get a report with corresponding records afterwards. My personal information should not be so readily available, and without my knowledge! Final Verdict Maybe its my older age, maybe its where I’m at in life with family, maybe its where I’m at in my career, but when I consider whether a conference experience was valuable I get to the core reason I attend: opportunities to learn, opportunities to network, opportunities to engage with Microsoft. Opportunities to Learn:  Sessions I attended were generally OK, with some really stand out ones on Day 2. I would love to see Microsoft adopt the Dojo format for a portion of their sessions. Hands On Labs are dull, lecture style sessions are great for information sharing. But a guided hands-on coding session (Read: Dojo) provides the best of both worlds. Being that all content is publically available online to everyone (Build attendee or not), the value of attending the conference sessions is decreased. The value though is in the discussions that take part in person afterwards, which leads to… Opportunities to Network: I enjoyed getting together with old friends and connecting with Twitter friends in person for the first time. I also had an opportunity to meet total strangers. So from a networking perspective, Build was fantastic! I still think it would have been great to have an area for ad-hoc discussions – where speakers could announce they’d be available for more questions after their sessions, or attendees who wanted to discuss more in depth on a topic with other attendees could arrange space. Some people have no problems being outgoing and making these things happen, but others are not and a structured model is more attractive. Opportunities to Engage with Microsoft: Hit and miss on this one. Outside of the vendor area, unless you cornered or reached out to a speaker, there wasn’t any defined way to connect with blue badges. And as I mentioned above, Microsoft didn’t have full representation in the vendor area (no Bing). All in all, Build was a fun party where I was informed about some new stuff and got some free swag. Was it worth the time away from home and the hit to my PD budget? I’d say Somewhat. Build is a great informational conference, but I wouldn’t call it a learning conference. Considering that TechEd seems to be moving to more of an IT Pro focus, independent developer conferences seem to be the best value for those looking to learn and not just be informed. With the rapid development cycle Microsoft is embracing, we’re already seeing Build happening twice within a 12 month period. If that continues, the value of attending Build in person starts to diminish – especially with so much content available online. If Microsoft wants Build to be a must-attend event in the future, they need to start incorporating aspects of Tech Ed, past PDCs, and other conferences so those that want to leave with more than free swag have something to attract them.

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• The Sensemaking Spectrum for Business Analytics: Translating from Data to Business Through Analysis

  - by Joe Lamantia

  One of the most compelling outcomes of our strategic research efforts over the past several years is a growing vocabulary that articulates our cumulative understanding of the deep structure of the domains of discovery and business analytics. Modes are one example of the deep structure we’ve found.  After looking at discovery activities across a very wide range of industries, question types, business needs, and problem solving approaches, we've identified distinct and recurring kinds of sensemaking activity, independent of context.  We label these activities Modes: Explore, compare, and comprehend are three of the nine recognizable modes.  Modes describe *how* people go about realizing insights.  (Read more about the programmatic research and formal academic grounding and discussion of the modes here: https://www.researchgate.net/publication/235971352_A_Taxonomy_of_Enterprise_Search_and_Discovery) By analogy to languages, modes are the 'verbs' of discovery activity.  When applied to the practical questions of product strategy and development, the modes of discovery allow one to identify what kinds of analytical activity a product, platform, or solution needs to support across a spread of usage scenarios, and then make concrete and well-informed decisions about every aspect of the solution, from high-level capabilities, to which specific types of information visualizations better enable these scenarios for the types of data users will analyze. The modes are a powerful generative tool for product making, but if you've spent time with young children, or had a really bad hangover (or both at the same time...), you understand the difficult of communicating using only verbs.  So I'm happy to share that we've found traction on another facet of the deep structure of discovery and business analytics.  Continuing the language analogy, we've identified some of the ‘nouns’ in the language of discovery: specifically, the consistently recurring aspects of a business that people are looking for insight into.  We call these discovery Subjects, since they identify *what* people focus on during discovery efforts, rather than *how* they go about discovery as with the Modes. Defining the collection of Subjects people repeatedly focus on allows us to understand and articulate sense making needs and activity in more specific, consistent, and complete fashion.  In combination with the Modes, we can use Subjects to concretely identify and define scenarios that describe people’s analytical needs and goals.  For example, a scenario such as ‘Explore [a Mode] the attrition rates [a Measure, one type of Subject] of our largest customers [Entities, another type of Subject] clearly captures the nature of the activity — exploration of trends vs. deep analysis of underlying factors — and the central focus — attrition rates for customers above a certain set of size criteria — from which follow many of the specifics needed to address this scenario in terms of data, analytical tools, and methods. We can also use Subjects to translate effectively between the different perspectives that shape discovery efforts, reducing ambiguity and increasing impact on both sides the perspective divide.  For example, from the language of business, which often motivates analytical work by asking questions in business terms, to the perspective of analysis.  The question posed to a Data Scientist or analyst may be something like “Why are sales of our new kinds of potato chips to our largest customers fluctuating unexpectedly this year?” or “Where can innovate, by expanding our product portfolio to meet unmet needs?”.  Analysts translate questions and beliefs like these into one or more empirical discovery efforts that more formally and granularly indicate the plan, methods, tools, and desired outcomes of analysis.  From the perspective of analysis this second question might become, “Which customer needs of type ‘A', identified and measured in terms of ‘B’, that are not directly or indirectly addressed by any of our current products, offer 'X' potential for ‘Y' positive return on the investment ‘Z' required to launch a new offering, in time frame ‘W’?  And how do these compare to each other?”.  Translation also happens from the perspective of analysis to the perspective of data; in terms of availability, quality, completeness, format, volume, etc. By implication, we are proposing that most working organizations — small and large, for profit and non-profit, domestic and international, and in the majority of industries — can be described for analytical purposes using this collection of Subjects.  This is a bold claim, but simplified articulation of complexity is one of the primary goals of sensemaking frameworks such as this one.  (And, yes, this is in fact a framework for making sense of sensemaking as a category of activity - but we’re not considering the recursive aspects of this exercise at the moment.) Compellingly, we can place the collection of subjects on a single continuum — we call it the Sensemaking Spectrum — that simply and coherently illustrates some of the most important relationships between the different types of Subjects, and also illuminates several of the fundamental dynamics shaping business analytics as a domain.  As a corollary, the Sensemaking Spectrum also suggests innovation opportunities for products and services related to business analytics. The first illustration below shows Subjects arrayed along the Sensemaking Spectrum; the second illustration presents examples of each kind of Subject.  Subjects appear in colors ranging from blue to reddish-orange, reflecting their place along the Spectrum, which indicates whether a Subject addresses more the viewpoint of systems and data (Data centric and blue), or people (User centric and orange).  This axis is shown explicitly above the Spectrum.  Annotations suggest how Subjects align with the three significant perspectives of Data, Analysis, and Business that shape business analytics activity.  This rendering makes explicit the translation and bridging function of Analysts as a role, and analysis as an activity. Subjects are best understood as fuzzy categories [http://georgelakoff.files.wordpress.com/2011/01/hedges-a-study-in-meaning-criteria-and-the-logic-of-fuzzy-concepts-journal-of-philosophical-logic-2-lakoff-19731.pdf], rather than tightly defined buckets.  For each Subject, we suggest some of the most common examples: Entities may be physical things such as named products, or locations (a building, or a city); they could be Concepts, such as satisfaction; or they could be Relationships between entities, such as the variety of possible connections that define linkage in social networks.  Likewise, Events may indicate a time and place in the dictionary sense; or they may be Transactions involving named entities; or take the form of Signals, such as ‘some Measure had some value at some time’ - what many enterprises understand as alerts.   The central story of the Spectrum is that though consumers of analytical insights (represented here by the Business perspective) need to work in terms of Subjects that are directly meaningful to their perspective — such as Themes, Plans, and Goals — the working realities of data (condition, structure, availability, completeness, cost) and the changing nature of most discovery efforts make direct engagement with source data in this fashion impossible.  Accordingly, business analytics as a domain is structured around the fundamental assumption that sense making depends on analytical transformation of data.  Analytical activity incrementally synthesizes more complex and larger scope Subjects from data in its starting condition, accumulating insight (and value) by moving through a progression of stages in which increasingly meaningful Subjects are iteratively synthesized from the data, and recombined with other Subjects.  The end goal of  ‘laddering’ successive transformations is to enable sense making from the business perspective, rather than the analytical perspective.Synthesis through laddering is typically accomplished by specialized Analysts using dedicated tools and methods. Beginning with some motivating question such as seeking opportunities to increase the efficiency (a Theme) of fulfillment processes to reach some level of profitability by the end of the year (Plan), Analysts will iteratively wrangle and transform source data Records, Values and Attributes into recognizable Entities, such as Products, that can be combined with Measures or other data into the Events (shipment of orders) that indicate the workings of the business.  More complex Subjects (to the right of the Spectrum) are composed of or make reference to less complex Subjects: a business Process such as Fulfillment will include Activities such as confirming, packing, and then shipping orders.  These Activities occur within or are conducted by organizational units such as teams of staff or partner firms (Networks), composed of Entities which are structured via Relationships, such as supplier and buyer.  The fulfillment process will involve other types of Entities, such as the products or services the business provides.  The success of the fulfillment process overall may be judged according to a sophisticated operating efficiency Model, which includes tiered Measures of business activity and health for the transactions and activities included.  All of this may be interpreted through an understanding of the operational domain of the businesses supply chain (a Domain).   We'll discuss the Spectrum in more depth in succeeding posts.

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• Open GL stars are not rendering

  - by Darestium

  I doing Nehe's Open GL Lesson 9. I'm using SFML for windowing, the strange thing is no stars are rendering. #include <SFML/System.hpp> #include <SFML/Window.hpp> #include <SFML/Graphics.hpp> #include <iostream> void processEvents(sf::Window *app); void processInput(sf::Window *app); void renderGlScene(sf::Window *app); void init(); int loadResources(); const int NUM_OF_STARS = 50; float triRot = 0.0f; float quadRot = 0.0f; bool twinkle = false; bool tKey = false; float zoom = 15.0f; float tilt = 90.0f; float spin = 0.0f; unsigned int loop; unsigned int texture_handle[1]; typedef struct { int r, g, b; float distance; float angle; } stars; stars star[NUM_OF_STARS]; int main() { sf::Window app(sf::VideoMode(800, 600, 32), "Nehe Lesson 9"); app.UseVerticalSync(false); init(); if (loadResources() == -1) { return EXIT_FAILURE; } while (app.IsOpened()) { processEvents(&app); processInput(&app); renderGlScene(&app); app.Display(); } return EXIT_SUCCESS; } int loadResources() { sf::Image img_data; // Load Texture if (!img_data.LoadFromFile("data/images/star.bmp")) { std::cout << "Could not load data/images/star.bmp"; return -1; } // Generate 1 texture glGenTextures(1, &texture_handle[0]); // Linear filtering glBindTexture(GL_TEXTURE_2D, texture_handle[0]); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, img_data.GetWidth(), img_data.GetHeight(), 0, GL_RGBA, GL_UNSIGNED_BYTE, img_data.GetPixelsPtr()); return 0; } void processInput(sf::Window *app) { const sf::Input& input = app->GetInput(); if (input.IsKeyDown(sf::Key::T) && !tKey) { tKey = true; twinkle = !twinkle; } if (!input.IsKeyDown(sf::Key::T)) { tKey = false; } if (input.IsKeyDown(sf::Key::Up)) { tilt -= 0.05f; } if (input.IsKeyDown(sf::Key::Down)) { tilt += 0.05f; } if (input.IsKeyDown(sf::Key::PageUp)) { zoom -= 0.02f; } if (input.IsKeyDown(sf::Key::Up)) { zoom += 0.02f; } } void init() { glClearDepth(1.f); glClearColor(0.f, 0.f, 0.f, 0.f); // Enable texturing glEnable(GL_TEXTURE_2D); //glDepthMask(GL_TRUE); // Setup a perpective projection glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluPerspective(45.f, 1.f, 1.f, 500.f); glShadeModel(GL_SMOOTH); glBlendFunc(GL_SRC_ALPHA, GL_ONE); glEnable(GL_BLEND); for (loop = 0; loop < NUM_OF_STARS; loop++) { star[loop].distance = (float)loop / NUM_OF_STARS * 5.0f; // Calculate distance from the centre // Give stars random rgb value star[loop].r = rand() % 256; star[loop].g = rand() % 256; star[loop].b = rand() % 256; } } void processEvents(sf::Window *app) { sf::Event event; while (app->GetEvent(event)) { if (event.Type == sf::Event::Closed) { app->Close(); } if (event.Type == sf::Event::KeyPressed && event.Key.Code == sf::Key::Escape) { app->Close(); } } } void renderGlScene(sf::Window *app) { app->SetActive(); // Clear color depth buffer glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Apply some transformations glMatrixMode(GL_MODELVIEW); glLoadIdentity(); // Select texture glBindTexture(GL_TEXTURE_2D, texture_handle[0]); for (loop = 0; loop < NUM_OF_STARS; loop++) { glLoadIdentity(); // Reset The View Before We Draw Each Star glTranslatef(0.0f, 0.0f, zoom); // Zoom Into The Screen (Using The Value In 'zoom') glRotatef(tilt, 1.0f, 0.0f, 0.0f); // Tilt The View (Using The Value In 'tilt') glRotatef(star[loop].angle, 0.0f, 1.0f, 0.0f); // Rotate To The Current Stars Angle glTranslatef(star[loop].distance, 0.0f, 0.0f); // Move Forward On The X Plane glRotatef(-star[loop].angle,0.0f,1.0f,0.0f); // Cancel The Current Stars Angle glRotatef(-tilt,1.0f,0.0f,0.0f); // Cancel The Screen Tilt if (twinkle) { glColor4ub(star[(NUM_OF_STARS - loop) - 1].r, star[(NUM_OF_STARS - loop)-1].g, star[(NUM_OF_STARS - loop) - 1].b, 255); glBegin(GL_QUADS); // Begin Drawing The Textured Quad glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 0.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 0.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 0.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 0.0f); glEnd(); // Done Drawing The Textured Quad } glRotatef(spin,0.0f,0.0f,1.0f); // Rotate The Star On The Z Axis // Assign A Color Using Bytes glColor4ub(star[loop].r, star[loop].g, star[loop].b, 255); glBegin(GL_QUADS); // Begin Drawing The Textured Quad glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f,-1.0f, 0.0f); glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f,-1.0f, 0.0f); glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 0.0f); glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 0.0f); glEnd(); // Done Drawing The Textured Quad spin += 0.01f; // Used To Spin The Stars star[loop].angle += (float)loop / NUM_OF_STARS; // Changes The Angle Of A Star star[loop].distance -= 0.01f; // Changes The Distance Of A Star if (star[loop].distance < 0.0f) { star[loop].distance += 5.0f; // Move The Star 5 Units From The Center star[loop].r = rand() % 256; // Give It A New Red Value star[loop].g = rand() % 256; // Give It A New Green Value star[loop].b = rand() % 256; // Give It A New Blue Value } } } I've looked over the code atleast 10 times now and I can't figure out the problem. Any help would be much appreciated.

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• DevConnections Spring 2010 Speaker Evals and Tips

  As a conference speaker, I always look forward to hearing from attendees whether they felt my sessions were valuable and worth their time.  Its always gratifying  get a high score, but of course its the (preferably constructive) criticism thats key to continued improvement.  Im by no means the best technical presenter around, and Im always looking for ways to improve. Ive recently spoken at a few events, including TechEd and an Ohio event called Stir Trek.  DevConnections was actually back in April, but theyre just getting their final evals out to speakers.  TechEd, of course, does online evals so immediately after your talks you can see what people think.  Ill try and post my TechEd evals in the next week or so. I gave 3 talks at DevConnections Spring 2010 / VS2010 Launch which I discussed in this previous blog post.  In this follow-up, Im just going to share some eval info and my thoughts on it, albeit a couple of months later. Pragmatic ASP.NET Tips, Tricks, and Tools Evals Turned In: 27 Overall Eval: 3.74 Average Score: 3.47 89% found the technical level Just Right.  7.4% thought it was too basic (3.6% did not respond).  Since nobody thought the content was Too complex, I could perhaps have added some more complex material, but having about 90% say its Just Right is pretty good. 92% said at least 50% of the material was new to them.  36% said 75% or more was new.  Thats also pretty good, I think. 77.8% can use the information immediately; 15% can use it within 2-6 months (7.2 % no response). Overall 78% rated the session Excellent, 18% Good, 4% Fair. All comments (9): Steve did a great job Excellent session! It was good. Im now super excited to attend Steves other sessions later today.  Very useful. One of the best speakers here.  Bring him back to future conferences please. Continue to have this session with new and old stuff.  I always find something I did not know about. Excellent!  This was the best session Ive seen all week. Did not increase font on all pages could not see. For Steve to have had more sessions. Note to self make the fonts bigger across the board.  Otherwise, this is all good for my ego. :)  This is always a very popular session and one I really enjoy giving.  Tips and Tricks talks are pretty easy because you dont have to go in depth with any particular thing, and theyre almost always with existing technology so youre not dealing with betas, lack of documentation, and other issues.  Its an easy session to do well, in my experience, and one which I think attendees definitely appreciate.   Whats New in ASP.NET MVC 2 Evals Turned In: 23 Overall Eval: 3.77 Average Score: 3.47 (wow, I cant believe I scored better on this talk than the tips and tricks talk, which Ive given many times and was more excited about) 96% found the technical level Just Right.  90% found 50% or more of the material to be new.  43% can use the info immediately, and another 43% can use it within 2-6 months I guess that speaks to adoption rates of MVC 2 among my attendees Overall 74% said the session was Excellent, 22% Good.  4% No Response. All Comments (6): Great job, thank you. Great speaker! Really good, a little lost in the code at some points, but great information. Speaker needs to repeat questions from audience for everyone to hear. Exceeded my expectations. Great speaker, very informative. I really do try to religiously repeat questions from the audience for everyone to hear, but obviously I didnt do it 100% of the time.  Note to self remember to repeat questions.  That and making fonts big are really basic speaker best practices, which just goes to prove that fundamentals are always something that can be perfected.   SOLIDify Your ASP.NET MVC 2 Application Evals Turned In: 8 (!) Overall Eval: 3.63 Average Score: 3.47 As I recall this was one of the last talks of the day / show, which might account for the low number of evals turned in.  I dont recall speaking to an empty room for this talk, although it certainly wasnt as crowded as the tips and tricks talk. 100% found the technical level Just Right.  100% found at least half the material new.  62.5% can use it at once and 37.5% within 2-6 months.  62.5% rated the session Excellent overall; 37.5% Good.  Im thinking there were 5 evals with all 4s checked and 3 with all 3s checked (4 = Excellent, 3 = Good) All Comments (3): This covered many topics Ive read about recently, and it helped reinforce them. It was a nice overview of the solid principle, but I thought there might be specifics for MVC2.  I am glad there is not. Move a little slower. Ok, so another fundamental dont go too fast.  Looks like I got one fundamental tip from the comments of each talk. My Take-Aways Remember the fundamentals.  Its worth going through a checklist prior to presenting to make sure these things are fresh in your mind.  Increase all font sizes.  Repeat all questions from audience members without microphones (this is also a great way to stall for time, btw).  Resist the urge to move too quickly especially if youre nervous or short of time.  Writing this up in a blog post also further reinforces these fundamentals for me, which is one of the main reasons why I do it I retain things better when I write them, and even moreso when I write them for public consumption since I have to really think about what Im saying.  And maybe a few of you find this interesting or helpful, which is a bonus. Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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• When is a Seek not a Seek?

  - by Paul White

  The following script creates a single-column clustered table containing the integers from 1 to 1,000 inclusive. IF OBJECT_ID(N'tempdb..#Test', N'U') IS NOT NULL DROP TABLE #Test ; GO CREATE TABLE #Test ( id INTEGER PRIMARY KEY CLUSTERED ); ; INSERT #Test (id) SELECT V.number FROM master.dbo.spt_values AS V WHERE V.[type] = N'P' AND V.number BETWEEN 1 AND 1000 ; Let’s say we need to find the rows with values from 100 to 170, excluding any values that divide exactly by 10.  One way to write that query would be: SELECT T.id FROM #Test AS T WHERE T.id IN ( 101,102,103,104,105,106,107,108,109, 111,112,113,114,115,116,117,118,119, 121,122,123,124,125,126,127,128,129, 131,132,133,134,135,136,137,138,139, 141,142,143,144,145,146,147,148,149, 151,152,153,154,155,156,157,158,159, 161,162,163,164,165,166,167,168,169 ) ; That query produces a pretty efficient-looking query plan: Knowing that the source column is defined as an INTEGER, we could also express the query this way: SELECT T.id FROM #Test AS T WHERE T.id >= 101 AND T.id <= 169 AND T.id % 10 > 0 ; We get a similar-looking plan: If you look closely, you might notice that the line connecting the two icons is a little thinner than before.  The first query is estimated to produce 61.9167 rows – very close to the 63 rows we know the query will return.  The second query presents a tougher challenge for SQL Server because it doesn’t know how to predict the selectivity of the modulo expression (T.id % 10 > 0).  Without that last line, the second query is estimated to produce 68.1667 rows – a slight overestimate.  Adding the opaque modulo expression results in SQL Server guessing at the selectivity.  As you may know, the selectivity guess for a greater-than operation is 30%, so the final estimate is 30% of 68.1667, which comes to 20.45 rows. The second difference is that the Clustered Index Seek is costed at 99% of the estimated total for the statement.  For some reason, the final SELECT operator is assigned a small cost of 0.0000484 units; I have absolutely no idea why this is so, or what it models.  Nevertheless, we can compare the total cost for both queries: the first one comes in at 0.0033501 units, and the second at 0.0034054.  The important point is that the second query is costed very slightly higher than the first, even though it is expected to produce many fewer rows (20.45 versus 61.9167). If you run the two queries, they produce exactly the same results, and both complete so quickly that it is impossible to measure CPU usage for a single execution.  We can, however, compare the I/O statistics for a single run by running the queries with STATISTICS IO ON: Table '#Test'. Scan count 63, logical reads 126, physical reads 0. Table '#Test'. Scan count 01, logical reads 002, physical reads 0. The query with the IN list uses 126 logical reads (and has a ‘scan count’ of 63), while the second query form completes with just 2 logical reads (and a ‘scan count’ of 1).  It is no coincidence that 126 = 63 * 2, by the way.  It is almost as if the first query is doing 63 seeks, compared to one for the second query. In fact, that is exactly what it is doing.  There is no indication of this in the graphical plan, or the tool-tip that appears when you hover your mouse over the Clustered Index Seek icon.  To see the 63 seek operations, you have click on the Seek icon and look in the Properties window (press F4, or right-click and choose from the menu): The Seek Predicates list shows a total of 63 seek operations – one for each of the values from the IN list contained in the first query.  I have expanded the first seek node to show the details; it is seeking down the clustered index to find the entry with the value 101.  Each of the other 62 nodes expands similarly, and the same information is contained (even more verbosely) in the XML form of the plan. Each of the 63 seek operations starts at the root of the clustered index B-tree and navigates down to the leaf page that contains the sought key value.  Our table is just large enough to need a separate root page, so each seek incurs 2 logical reads (one for the root, and one for the leaf).  We can see the index depth using the INDEXPROPERTY function, or by using the a DMV: SELECT S.index_type_desc, S.index_depth FROM sys.dm_db_index_physical_stats ( DB_ID(N'tempdb'), OBJECT_ID(N'tempdb..#Test', N'U'), 1, 1, DEFAULT ) AS S ; Let’s look now at the Properties window when the Clustered Index Seek from the second query is selected: There is just one seek operation, which starts at the root of the index and navigates the B-tree looking for the first key that matches the Start range condition (id >= 101).  It then continues to read records at the leaf level of the index (following links between leaf-level pages if necessary) until it finds a row that does not meet the End range condition (id <= 169).  Every row that meets the seek range condition is also tested against the Residual Predicate highlighted above (id % 10 > 0), and is only returned if it matches that as well. You will not be surprised that the single seek (with a range scan and residual predicate) is much more efficient than 63 singleton seeks.  It is not 63 times more efficient (as the logical reads comparison would suggest), but it is around three times faster.  Let’s run both query forms 10,000 times and measure the elapsed time: DECLARE @i INTEGER, @n INTEGER = 10000, @s DATETIME = GETDATE() ; SET NOCOUNT ON; SET STATISTICS XML OFF; ; WHILE @n > 0 BEGIN SELECT @i = T.id FROM #Test AS T WHERE T.id IN ( 101,102,103,104,105,106,107,108,109, 111,112,113,114,115,116,117,118,119, 121,122,123,124,125,126,127,128,129, 131,132,133,134,135,136,137,138,139, 141,142,143,144,145,146,147,148,149, 151,152,153,154,155,156,157,158,159, 161,162,163,164,165,166,167,168,169 ) ; SET @n -= 1; END ; PRINT DATEDIFF(MILLISECOND, @s, GETDATE()) ; GO DECLARE @i INTEGER, @n INTEGER = 10000, @s DATETIME = GETDATE() ; SET NOCOUNT ON ; WHILE @n > 0 BEGIN SELECT @i = T.id FROM #Test AS T WHERE T.id >= 101 AND T.id <= 169 AND T.id % 10 > 0 ; SET @n -= 1; END ; PRINT DATEDIFF(MILLISECOND, @s, GETDATE()) ; On my laptop, running SQL Server 2008 build 4272 (SP2 CU2), the IN form of the query takes around 830ms and the range query about 300ms.  The main point of this post is not performance, however – it is meant as an introduction to the next few parts in this mini-series that will continue to explore scans and seeks in detail. When is a seek not a seek?  When it is 63 seeks © Paul White 2011 email: [email protected] twitter: @SQL_kiwi

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• RiverTrail - JavaScript GPPGU Data Parallelism

  - by JoshReuben

  Where is WebCL ? The Khronos WebCL working group is working on a JavaScript binding to the OpenCL standard so that HTML 5 compliant browsers can host GPGPU web apps – e.g. for image processing or physics for WebGL games - http://www.khronos.org/webcl/ . While Nokia & Samsung have some protype WebCL APIs, Intel has one-upped them with a higher level of abstraction: RiverTrail. Intro to RiverTrail Intel Labs JavaScript RiverTrail provides GPU accelerated SIMD data-parallelism in web applications via a familiar JavaScript programming paradigm. It extends JavaScript with simple deterministic data-parallel constructs that are translated at runtime into a low-level hardware abstraction layer. With its high-level JS API, programmers do not have to learn a new language or explicitly manage threads, orchestrate shared data synchronization or scheduling. It has been proposed as a draft specification to ECMA a (known as ECMA strawman). RiverTrail runs in all popular browsers (except I.E. of course). To get started, download a prebuilt version https://github.com/downloads/RiverTrail/RiverTrail/rivertrail-0.17.xpi , install Intel's OpenCL SDK http://www.intel.com/go/opencl and try out the interactive River Trail shell http://rivertrail.github.com/interactive For a video overview, see  http://www.youtube.com/watch?v=jueg6zB5XaM . ParallelArray the ParallelArray type is the central component of this API & is a JS object that contains ordered collections of scalars – i.e. multidimensional uniform arrays. A shape property describes the dimensionality and size– e.g. a 2D RGBA image will have shape [height, width, 4]. ParallelArrays are immutable & fluent – they are manipulated by invoking methods on them which produce new ParallelArray objects. ParallelArray supports several constructors over arrays, functions & even the canvas. // Create an empty Parallel Array var pa = new ParallelArray(); // pa0 = <>   // Create a ParallelArray out of a nested JS array. // Note that the inner arrays are also ParallelArrays var pa = new ParallelArray([ [0,1], [2,3], [4,5] ]); // pa1 = <<0,1>, <2,3>, <4.5>>   // Create a two-dimensional ParallelArray with shape [3, 2] using the comprehension constructor var pa = new ParallelArray([3, 2], function(iv){return iv[0] * iv[1];}); // pa7 = <<0,0>, <0,1>, <0,2>>   // Create a ParallelArray from canvas.  This creates a PA with shape [w, h, 4], var pa = new ParallelArray(canvas); // pa8 = CanvasPixelArray   ParallelArray exposes fluent API functions that take an elemental JS function for data manipulation: map, combine, scan, filter, and scatter that return a new ParallelArray. Other functions are scalar - reduce  returns a scalar value & get returns the value located at a given index. The onus is on the developer to ensure that the elemental function does not defeat data parallelization optimization (avoid global var manipulation, recursion). For reduce & scan, order is not guaranteed - the onus is on the dev to provide an elemental function that is commutative and associative so that scan will be deterministic – E.g. Sum is associative, but Avg is not. map Applies a provided elemental function to each element of the source array and stores the result in the corresponding position in the result array. The map method is shape preserving & index free - can not inspect neighboring values. // Adding one to each element. var source = new ParallelArray([1,2,3,4,5]); var plusOne = source.map(function inc(v) {     return v+1; }); //<2,3,4,5,6> combine Combine is similar to map, except an index is provided. This allows elemental functions to access elements from the source array relative to the one at the current index position. While the map method operates on the outermost dimension only, combine, can choose how deep to traverse - it provides a depth argument to specify the number of dimensions it iterates over. The elemental function of combine accesses the source array & the current index within it - element is computed by calling the get method of the source ParallelArray object with index i as argument. It requires more code but is more expressive. var source = new ParallelArray([1,2,3,4,5]); var plusOne = source.combine(function inc(i) { return this.get(i)+1; }); reduce reduces the elements from an array to a single scalar result – e.g. Sum. // Calculate the sum of the elements var source = new ParallelArray([1,2,3,4,5]); var sum = source.reduce(function plus(a,b) { return a+b; }); scan Like reduce, but stores the intermediate results – return a ParallelArray whose ith elements is the results of using the elemental function to reduce the elements between 0 and I in the original ParallelArray. // do a partial sum var source = new ParallelArray([1,2,3,4,5]); var psum = source.scan(function plus(a,b) { return a+b; }); //<1, 3, 6, 10, 15> scatter a reordering function - specify for a certain source index where it should be stored in the result array. An optional conflict function can prevent an exception if two source values are assigned the same position of the result: var source = new ParallelArray([1,2,3,4,5]); var reorder = source.scatter([4,0,3,1,2]); // <2, 4, 5, 3, 1> // if there is a conflict use the max. use 33 as a default value. var reorder = source.scatter([4,0,3,4,2], 33, function max(a, b) {return a>b?a:b; }); //<2, 33, 5, 3, 4> filter // filter out values that are not even var source = new ParallelArray([1,2,3,4,5]); var even = source.filter(function even(iv) { return (this.get(iv) % 2) == 0; }); // <2,4> Flatten used to collapse the outer dimensions of an array into a single dimension. pa = new ParallelArray([ [1,2], [3,4] ]); // <<1,2>,<3,4>> pa.flatten(); // <1,2,3,4> Partition used to restore the original shape of the array. var pa = new ParallelArray([1,2,3,4]); // <1,2,3,4> pa.partition(2); // <<1,2>,<3,4>> Get return value found at the indices or undefined if no such value exists. var pa = new ParallelArray([0,1,2,3,4], [10,11,12,13,14], [20,21,22,23,24]) pa.get([1,1]); // 11 pa.get([1]); // <10,11,12,13,14>

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• Light following me around the room. Something is wrong with my shader!

  - by Robinson

  I'm trying to do a spot (Blinn) light, with falloff and attenuation. It seems to be working OK except I have a bit of a space problem. That is, whenever I move the camera the light moves to maintain the same relative position, rather than changing with the camera. This results in the light moving around, i.e. not always falling on the same surfaces. It's as if there's a flashlight attached to the camera. I'm transforming the lights beforehand into view space, so Light_Position and Light_Direction are already in eye space (I hope!). I made a little movie of what it looks like here: My camera rotating around a point inside a box. The light is fixed in the centre up and its "look at" point in a fixed position in front of it. As you can see, as the camera rotates around the origin (always looking at the centre), so don't think the box is rotating (!). The lighting follows it around. To start, some code. This is how I'm transforming the light into view space (it gets passed into the shader already in view space): // Compute eye-space light position. Math::Vector3d eyeSpacePosition = MyCamera->ViewMatrix() * MyLightPosition; MyShaderVariables->Set(MyLightPositionIndex, eyeSpacePosition); // Compute eye-space light direction vector. Math::Vector3d eyeSpaceDirection = Math::Unit(MyLightLookAt - MyLightPosition); MyCamera->ViewMatrixInverseTranspose().TransformNormal(eyeSpaceDirection); MyShaderVariables->Set(MyLightDirectionIndex, eyeSpaceDirection); Can anyone give me a clue as to what I'm doing wrong here? I think the light should remain looking at a fixed point on the box, regardless of the camera orientation. Here are the vertex and pixel shaders: /////////////////////////////////////////////////// // Vertex Shader /////////////////////////////////////////////////// #version 420 /////////////////////////////////////////////////// // Uniform Buffer Structures /////////////////////////////////////////////////// // Camera. layout (std140) uniform Camera { mat4 Camera_View; mat4 Camera_ViewInverseTranspose; mat4 Camera_Projection; }; // Matrices per model. layout (std140) uniform Model { mat4 Model_World; mat4 Model_WorldView; mat4 Model_WorldViewInverseTranspose; mat4 Model_WorldViewProjection; }; // Spotlight. layout (std140) uniform OmniLight { float Light_Intensity; vec3 Light_Position; vec3 Light_Direction; vec4 Light_Ambient_Colour; vec4 Light_Diffuse_Colour; vec4 Light_Specular_Colour; float Light_Attenuation_Min; float Light_Attenuation_Max; float Light_Cone_Min; float Light_Cone_Max; }; /////////////////////////////////////////////////// // Streams (per vertex) /////////////////////////////////////////////////// layout(location = 0) in vec3 attrib_Position; layout(location = 1) in vec3 attrib_Normal; layout(location = 2) in vec3 attrib_Tangent; layout(location = 3) in vec3 attrib_BiNormal; layout(location = 4) in vec2 attrib_Texture; /////////////////////////////////////////////////// // Output streams (per vertex) /////////////////////////////////////////////////// out vec3 attrib_Fragment_Normal; out vec4 attrib_Fragment_Position; out vec2 attrib_Fragment_Texture; out vec3 attrib_Fragment_Light; out vec3 attrib_Fragment_Eye; /////////////////////////////////////////////////// // Main /////////////////////////////////////////////////// void main() { // Transform normal into eye space attrib_Fragment_Normal = (Model_WorldViewInverseTranspose * vec4(attrib_Normal, 0.0)).xyz; // Transform vertex into eye space (world * view * vertex = eye) vec4 position = Model_WorldView * vec4(attrib_Position, 1.0); // Compute vector from eye space vertex to light (light is in eye space already) attrib_Fragment_Light = Light_Position - position.xyz; // Compute vector from the vertex to the eye (which is now at the origin). attrib_Fragment_Eye = -position.xyz; // Output texture coord. attrib_Fragment_Texture = attrib_Texture; // Compute vertex position by applying camera projection. gl_Position = Camera_Projection * position; } and the pixel shader: /////////////////////////////////////////////////// // Pixel Shader /////////////////////////////////////////////////// #version 420 /////////////////////////////////////////////////// // Samplers /////////////////////////////////////////////////// uniform sampler2D Map_Diffuse; /////////////////////////////////////////////////// // Global Uniforms /////////////////////////////////////////////////// // Material. layout (std140) uniform Material { vec4 Material_Ambient_Colour; vec4 Material_Diffuse_Colour; vec4 Material_Specular_Colour; vec4 Material_Emissive_Colour; float Material_Shininess; float Material_Strength; }; // Spotlight. layout (std140) uniform OmniLight { float Light_Intensity; vec3 Light_Position; vec3 Light_Direction; vec4 Light_Ambient_Colour; vec4 Light_Diffuse_Colour; vec4 Light_Specular_Colour; float Light_Attenuation_Min; float Light_Attenuation_Max; float Light_Cone_Min; float Light_Cone_Max; }; /////////////////////////////////////////////////// // Input streams (per vertex) /////////////////////////////////////////////////// in vec3 attrib_Fragment_Normal; in vec3 attrib_Fragment_Position; in vec2 attrib_Fragment_Texture; in vec3 attrib_Fragment_Light; in vec3 attrib_Fragment_Eye; /////////////////////////////////////////////////// // Result /////////////////////////////////////////////////// out vec4 Out_Colour; /////////////////////////////////////////////////// // Main /////////////////////////////////////////////////// void main(void) { // Compute N dot L. vec3 N = normalize(attrib_Fragment_Normal); vec3 L = normalize(attrib_Fragment_Light); vec3 E = normalize(attrib_Fragment_Eye); vec3 H = normalize(L + E); float NdotL = clamp(dot(L,N), 0.0, 1.0); float NdotH = clamp(dot(N,H), 0.0, 1.0); // Compute ambient term. vec4 ambient = Material_Ambient_Colour * Light_Ambient_Colour; // Diffuse. vec4 diffuse = texture2D(Map_Diffuse, attrib_Fragment_Texture) * Light_Diffuse_Colour * Material_Diffuse_Colour * NdotL; // Specular. float specularIntensity = pow(NdotH, Material_Shininess) * Material_Strength; vec4 specular = Light_Specular_Colour * Material_Specular_Colour * specularIntensity; // Light attenuation (so we don't have to use 1 - x, we step between Max and Min). float d = length(-attrib_Fragment_Light); float attenuation = smoothstep(Light_Attenuation_Max, Light_Attenuation_Min, d); // Adjust attenuation based on light cone. float LdotS = dot(-L, Light_Direction), CosI = Light_Cone_Min - Light_Cone_Max; attenuation *= clamp((LdotS - Light_Cone_Max) / CosI, 0.0, 1.0); // Final colour. Out_Colour = (ambient + diffuse + specular) * Light_Intensity * attenuation; }

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• JavaOne Session Report: “50 Tips in 50 Minutes for GlassFish Fans”

  - by Janice J. Heiss

  At JavaOne 2012 on Monday, Oracle’s Engineer Chris Kasso, and Technology Evangelist Arun Gupta, presented a head-spinning session (CON4701) in which they offered 50 tips for GlassFish fans. Kasso and Gupta alternated back and forth with each presenting 10 tips at a time. An audience of about (appropriately) 50 attentive and appreciative developers was on hand in what has to be one of the most information-packed sessions ever at JavaOne!Aside: I experienced one of the quiet joys of JavaOne when, just before the session began, I spotted Java Champion and JavaOne Rock Star Adam Bien sitting nearby – Adam is someone I have been fortunate to know for many years.GlassFish is a freely available, commercially supported Java EE reference implementation. The session prioritized quantity of tips over depth of information and offered tips that are intended for both seasoned and new users, that are meant to increase the range of functional options available to GlassFish users. The focus was on lesser-known dimensions of GlassFish. Attendees were encouraged to pursue tips that contained new information for them. All 50 tips can be accessed here.Below are several examples of more elaborate tips and a final practical tip on how to get in touch with these folks. Tip #1: Using the login Command * To execute a remote command with asadmin you must provide the admin's user name and password.* The login command allows you to store the login credentials to be reused in subsequent commands.* Can be logged into multiple servers (distinguish by host and port). Example:     % asadmin --host ouch login     Enter admin user name [default: admin]>     Enter admin password>     Login information relevant to admin user name [admin]     for host [ouch] and admin port [4848] stored at     [/Users/ckasso/.asadminpass] successfully.     Make sure that this file remains protected.     Information stored in this file will be used by     asadmin commands to manage the associated domain.     Command login executed successfully.     % asadmin --host ouch list-clusters     c1 not running     Command list-clusters executed successfully.Tip #4: Using the AS_DEBUG Env Variable* Environment variable to control client side debug output* Exposes: command processing info URL used to access the command:                           http://localhost:4848/__asadmin/uptime Raw response from the server Example:   % export AS_DEBUG=true  % asadmin uptime  CLASSPATH= ./../glassfish/modules/admin-cli.jar  Commands: [uptime]  asadmin extension directory: /work/gf-3.1.2/glassfish3/glassfish/lib/asadm      ------- RAW RESPONSE  ---------   Signature-Version: 1.0   message: Up 7 mins 10 secs   milliseconds_value: 430194   keys: milliseconds   milliseconds_name: milliseconds   use-main-children-attribute: false   exit-code: SUCCESS  ------- RAW RESPONSE  ---------Tip #11: Using Password Aliases * Some resources require a password to access (e.g. DB, JMS, etc.).* The resource connector is defined in the domain.xml.Example:Suppose the DB resource you wish to access requires an entry like this in the domain.xml:     <property name="password" value="secretp@ssword"/>But company policies do not allow you to store the password in the clear.* Use password aliases to avoid storing the password in the domain.xml* Create a password alias:     % asadmin create-password-alias DB_pw_alias     Enter the alias password>     Enter the alias password again>     Command create-password-alias executed successfully.* The password is stored in domain's encrypted keystore.* Now update the password value in the domain.xml:     <property name="password" value="${ALIAS=DB_pw_alias}"/>Tip #21: How to Start GlassFish as a Service * Configuring a server to automatically start at boot can be tedious.* Each platform does it differently.* The create-service command makes this easy.   Windows: creates a Windows service Linux: /etc/init.d script Solaris: Service Management Facility (SMF) service * Must execute create-service with admin privileges.* Can be used for the DAS or instances* Try it first with the --dry-run option.* There is a (unsupported) _delete-serverExample:     # asadmin create-service domain1     The Service was created successfully. Here are the details:     Name of the service:application/GlassFish/domain1     Type of the service:Domain     Configuration location of the service:/work/gf-3.1.2.2/glassfish3/glassfish/domains     Manifest file location on the system:/var/svc/manifest/application/GlassFish/domain1_work_gf-3.1.2.2_glassfish3_glassfish_domains/Domain-service-smf.xml.     You have created the service but you need to start it yourself. Here are the most typical Solaris commands of interest:     * /usr/bin/svcs  -a | grep domain1  // status     * /usr/sbin/svcadm enable domain1 // start     * /usr/sbin/svcadm disable domain1 // stop     * /usr/sbin/svccfg delete domain1 // uninstallTip #34: Posting a Command via REST* Use wget/curl to execute commands on the DAS.Example:  Deploying an application   % curl -s -S \       -H 'Accept: application/json' -X POST \       -H 'X-Requested-By: anyvalue' \       -F id=@/path/to/application.war \       -F force=true http://localhost:4848/management/domain/applications/application* Use @ before a file name to tell curl to send the file's contents.* The force option tells GlassFish to force the deployment in case the application is already deployed.* Use wget/curl to execute commands on the DAS.Example:  Deploying an application   % curl -s -S \       -H 'Accept: application/json' -X POST \       -H 'X-Requested-By: anyvalue' \       -F id=@/path/to/application.war \       -F force=true http://localhost:4848/management/domain/applications/application* Use @ before a file name to tell curl to send the file's contents.* The force option tells GlassFish to force the deployment in case the application is already deployed.Tip #46: Upgrading to a Newer Version * Upgrade applications and configuration from an earlier version* Upgrade Tool: Side-by-side upgrade– GUI: asupgrade– CLI: asupgrade --c– What happens ?* Copies older source domain -> target domain directory* asadmin start-domain --upgrade* Update Tool and pkg: In-place upgrade– GUI: updatetool, install all Available Updates– CLI: pkg image-update– Upgrade the domain* asadmin start-domain --upgradeTip #50: How to reach us?* GlassFish Forum: http://www.java.net/forums/glassfish/glassfish* [email protected]* @glassfish* facebook.com/glassfish* youtube.com/GlassFishVideos* blogs.oracle.com/theaquariumArun Gupta acknowledged that their method of presentation was experimental and actively solicited feedback about the session. The best way to reach them is on the GlassFish user forum.In addition, check out Gupta’s new book Java EE 6 Pocket Guide.

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• Organization &amp; Architecture UNISA Studies &ndash; Chap 4

  - by MarkPearl

  Learning Outcomes Explain the characteristics of memory systems Describe the memory hierarchy Discuss cache memory principles Discuss issues relevant to cache design Describe the cache organization of the Pentium Computer Memory Systems There are key characteristics of memory… Location – internal or external Capacity – expressed in terms of bytes Unit of Transfer – the number of bits read out of or written into memory at a time Access Method – sequential, direct, random or associative From a users perspective the two most important characteristics of memory are… Capacity Performance – access time, memory cycle time, transfer rate The trade off for memory happens along three axis… Faster access time, greater cost per bit Greater capacity, smaller cost per bit Greater capacity, slower access time This leads to people using a tiered approach in their use of memory   As one goes down the hierarchy, the following occurs… Decreasing cost per bit Increasing capacity Increasing access time Decreasing frequency of access of the memory by the processor The use of two levels of memory to reduce average access time works in principle, but only if conditions 1 to 4 apply. A variety of technologies exist that allow us to accomplish this. Thus it is possible to organize data across the hierarchy such that the percentage of accesses to each successively lower level is substantially less than that of the level above. A portion of main memory can be used as a buffer to hold data temporarily that is to be read out to disk. This is sometimes referred to as a disk cache and improves performance in two ways… Disk writes are clustered. Instead of many small transfers of data, we have a few large transfers of data. This improves disk performance and minimizes processor involvement. Some data designed for write-out may be referenced by a program before the next dump to disk. In that case the data is retrieved rapidly from the software cache rather than slowly from disk. Cache Memory Principles Cache memory is substantially faster than main memory. A caching system works as follows.. When a processor attempts to read a word of memory, a check is made to see if this in in cache memory… If it is, the data is supplied, If it is not in the cache, a block of main memory, consisting of a fixed number of words is loaded to the cache. Because of the phenomenon of locality of references, when a block of data is fetched into the cache, it is likely that there will be future references to that same memory location or to other words in the block. Elements of Cache Design While there are a large number of cache implementations, there are a few basic design elements that serve to classify and differentiate cache architectures… Cache Addresses Cache Size Mapping Function Replacement Algorithm Write Policy Line Size Number of Caches Cache Addresses Almost all non-embedded processors support virtual memory. Virtual memory in essence allows a program to address memory from a logical point of view without needing to worry about the amount of physical memory available. When virtual addresses are used the designer may choose to place the cache between the MMU (memory management unit) and the processor or between the MMU and main memory. The disadvantage of virtual memory is that most virtual memory systems supply each application with the same virtual memory address space (each application sees virtual memory starting at memory address 0), which means the cache memory must be completely flushed with each application context switch or extra bits must be added to each line of the cache to identify which virtual address space the address refers to. Cache Size We would like the size of the cache to be small enough so that the overall average cost per bit is close to that of main memory alone and large enough so that the overall average access time is close to that of the cache alone. Also, larger caches are slightly slower than smaller ones. Mapping Function Because there are fewer cache lines than main memory blocks, an algorithm is needed for mapping main memory blocks into cache lines. The choice of mapping function dictates how the cache is organized. Three techniques can be used… Direct – simplest technique, maps each block of main memory into only one possible cache line Associative – Each main memory block to be loaded into any line of the cache Set Associative – exhibits the strengths of both the direct and associative approaches while reducing their disadvantages For detailed explanations of each approach – read the text book (page 148 – 154) Replacement Algorithm For associative and set associating mapping a replacement algorithm is needed to determine which of the existing blocks in the cache must be replaced by a new block. There are four common approaches… LRU (Least recently used) FIFO (First in first out) LFU (Least frequently used) Random selection Write Policy When a block resident in the cache is to be replaced, there are two cases to consider If no writes to that block have happened in the cache – discard it If a write has occurred, a process needs to be initiated where the changes in the cache are propagated back to the main memory. There are several approaches to achieve this including… Write Through – all writes to the cache are done to the main memory as well at the point of the change Write Back – when a block is replaced, all dirty bits are written back to main memory The problem is complicated when we have multiple caches, there are techniques to accommodate for this but I have not summarized them. Line Size When a block of data is retrieved and placed in the cache, not only the desired word but also some number of adjacent words are retrieved. As the block size increases from very small to larger sizes, the hit ratio will at first increase because of the principle of locality, which states that the data in the vicinity of a referenced word are likely to be referenced in the near future. As the block size increases, more useful data are brought into cache. The hit ratio will begin to decrease as the block becomes even bigger and the probability of using the newly fetched information becomes less than the probability of using the newly fetched information that has to be replaced. Two specific effects come into play… Larger blocks reduce the number of blocks that fit into a cache. Because each block fetch overwrites older cache contents, a small number of blocks results in data being overwritten shortly after they are fetched. As a block becomes larger, each additional word is farther from the requested word and therefore less likely to be needed in the near future. The relationship between block size and hit ratio is complex, and no set approach is judged to be the best in all circumstances.   Pentium 4 and ARM cache organizations The processor core consists of four major components: Fetch/decode unit – fetches program instruction in order from the L2 cache, decodes these into a series of micro-operations, and stores the results in the L2 instruction cache Out-of-order execution logic – Schedules execution of the micro-operations subject to data dependencies and resource availability – thus micro-operations may be scheduled for execution in a different order than they were fetched from the instruction stream. As time permits, this unit schedules speculative execution of micro-operations that may be required in the future Execution units – These units execute micro-operations, fetching the required data from the L1 data cache and temporarily storing results in registers Memory subsystem – This unit includes the L2 and L3 caches and the system bus, which is used to access main memory when the L1 and L2 caches have a cache miss and to access the system I/O resources

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• Who could ask for more with LESS CSS? (Part 2 of 3&ndash;Setup)

  - by ToStringTheory

  Welcome to part two in my series covering the LESS CSS language.  In the first post, I covered the two major CSS precompiled languages - LESS and SASS to a small extent, iterating over some of the features that you could expect to find in them.  In this post, I will go a little further in depth into the setup and execution of using the LESS framework. Introduction It really doesn’t take too much to get LESS working in your project.  The basic workflow will be including the necessary translator in your project, defining bundles for the LESS files, add the necessary code to your layouts.cshtml file, and finally add in all your necessary styles to the LESS files!  Lets get started… New Project Just like all great experiments in Visual Studio, start up a File > New Project, and create a new MVC 4 Web Application.  The Base Package After you have the new project spun up, use the Nuget Package Manager to install the Bundle Transformer: LESS package. This will take care of installing the main translator that we will be using for LESS code (dotless which is another Nuget package), as well as the core framework for the Bundle Transformer library.  The installation will come up with some instructions in a readme file on how to modify your web.config to handle all your *.less requests through the Bundle Transformer, which passes the translating onto dotless. Where To Put These LESS Files?! This step isn’t really a requirement, however I find that I don’t like how ASP.Net MVC just has a content directory where they store CSS, content images, css images….  In my project, I went ahead and created a new directory just for styles – LESS files, CSS files, and images that are only referenced in LESS or CSS.  Ignore the MVC directory as this was my testbed for another project I was working on at the same time.  As you can see here, I have: A top level directory for images which contains only images used in a page A top level directory for scripts A top level directory for Styles A few directories for plugins I am using (Colrizr, JQueryUI, Farbtastic) Multiple *.less files for different functions (I’ll go over these in a minute) I find that this layout offers the best separation of content types.  Bring Out Your Bundles! The next thing that we need to do is add in the necessary code for the bundling of these LESS files.  Go ahead and open your BundleConfig.cs file, usually located in the /App_Start/ folder of the project.  As you will see in a minute, instead of using the method Microsoft does in the base MVC 4 project, I change things up a bit.  Define Constants The first thing I do is define constants for each of the virtual paths that will be used in the bundler: The main reason is that I hate magic strings in my program, so the fact that you first defined a virtual path in the BundleConfig file, and then used that path in the _Layout.cshtml file really irked me. Add Bundles to the BundleCollection Next, I am going to define the bundles for my styles in my AddStyleBundles method: That is all it takes to get all of my styles in play with LESS.  The CssTransformer and NullOrderer types come from the Bundle Transformer we grabbed earlier.  If we didn’t use that package, we would have to write our own function (not too hard, but why do it if it’s been done). I use the site.less file as my main hub for LESS - I will cover that more in the next section. Add Bundles To Layout.cshtml File With the constants in the BundleConfig file, instead of having to use the same magic string I defined for the bundle virtual path, I am able to do this: Notice here that besides the RenderSection magic strings (something I am working on in another side project), all of the bundles are now based on const strings.  If I need to change the virtual path, I only have to do it in one place.  Nifty! Get Started! We are now ready to roll!  As I said in the previous section, I use the site.less file as a central hub for my styles: As seen here, I have a reset.css file which is a simple CSS reset.  Next, I have created a file for managing all my color variables – colors.less: Here, you can see some of the standards I started to use, in this case for color variables.  I define all color variables with the @col prefix.  Currently, I am going for verbose variable names. The next file imported is my font.less file that defines the typeface information for the site: Simple enough.  A couple of imports for fonts from Google, and then declaring variables for use throughout LESS.  I also set up the heading sizes, margins, etc..  You can also see my current standardization for font declaration strings – @font. Next, I pull in a mixins.less file that I grabbed from the Twitter Bootstrap library that gives some useful parameterized mixins for use such as border-radius, gradient, box-shadow, etc… The common.less file is a file that just contains items that I will be defining that can be used across all my LESS files.  Kind of like my own mixins or font-helpers: Finally I have my layout.less file that contains all of my definitions for general site layout – width, main/sidebar widths, footer layout, etc: That’s it!  For the rest of my one off definitions/corrections, I am currently putting them into the site.less file beneath my original imports Note Probably my favorite side effect of using the LESS handler/translator while bundling is that it also does a CSS checkup when rendering…  See, when your web.config is set to debug, bundling will output the url to the direct less file, not the bundle, and the http handler intercepts the call, compiles the less, and returns the result.  If there is an error in your LESS code, the CSS file can be returned empty, or may have the error output as a comment on the first couple lines. If you have the web.config set to not debug, then if there is an error in your code, you will end up with the usual ASP.Net exception page (unless you catch the exception of course), with information regarding the failure of the conversion, such as brace mismatch, undefined variable, etc…  I find it nifty. Conclusion This is really just the beginning.  LESS is very powerful and exciting!  My next post will show an actual working example of why LESS is so powerful with its functions and variables…  At least I hope it will!  As for now, if you have any questions, comments, or suggestions on my current practice, I would love to hear them!  Feel free to drop a comment or shoot me an email using the contact page.  In the mean time, I plan on posting the final post in this series tomorrow or the day after, with my side project, as well as a whole base ASP.Net MVC4 templated project with LESS added in it so that you can check out the layout I have in this post.  Until next time…

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