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  • SQLAuthority News – Author Visit – SQL Server 2008 R2 Launch

    - by pinaldave
    June 11, 2010 was a wonderful day because I attended the very first SQL Server 2008 R2 Launch event held by Microsoft at Mumbai. I traveled to Mumbai from my home town, Ahmedabad. The event was located at one of the best hotels in Mumbai,”The Leela”. SQL Server R2 Launch was an evening event that had a few interesting talks. SQL PASS is associated with this event as one of the partners and its goal is to increase the awareness of the Community about SQL Server. I met many interesting people and had a great networking opportunity at the event. This event was kicked off with an awesome laser show and a “Welcome” video, which was followed by a Microsoft Executive session wherein there were several interesting demo. The very first demo was about Powerpivot. I knew beforehand that there will be Powerpivot demos because it is a very popular subject; however, I was really hoping to see other interesting demos from SQL Server 2008 R2. And believe me; I was happier to see the later demos. There were demos from SQL Server Utility Control Point, as well an integration of Bing Map with Reporting Servers. I really enjoyed the interactive and informative session by Shivaram Venkatesh. He had excellent presentation skills as well as ample technical knowledge to keep the audience attentive. I really liked his presentations skills wherein he did not read the whole slide deck; rather, he picked one point and using that point he told the story of the whole slide deck. I also enjoyed my conversation with Afaq Choonawala, who is one of the “gem guys” in Microsoft. I also want to acknowledge Ashwin Kini and Mohit Panchal for their excellent support to this event. Mumbai IT Pro is a user group which you can really count on for any kind of help. After excellent demos and a vibrant start of the event, all the audience was jazzed up. There were two vendors’ sessions right after the first session. Intel had 15 minutes to present; however, Intel’s representative, who had good knowledge of the subject, had nearly 30+ slides in his presentation, so he had to rush a bit to cover the whole slide deck. Intel presentations were followed up by another vendor presentation from NetApp. I have previously heard about this tool. After I saw the demo which did not work the first time the Net App presenter demonstrated it, I started to have a doubt on this product. I personally went to clarify my doubt to the demo booth after the presentation was over, but I realize the NetApp presenter or booth owner had absolutely a POOR KNOWLEDGE of SQL Server and even of their own NetApp product. The NetApp people tried to misguide us and when we argued, they started to say different things against what they said earlier. At one point in their presentation, they claimed their application does something very fast, which did not really happen in front of all the audience. They blamed SQL Server R2 DBCC CHECKDB command for their product’s failed demonstration. I know that NetApp has many great products; however, this one was not conveyed clearly and even created a negative impression to all of us. Well, let us not judge the potential, fun, education and enigma of the launch event through a small glitch. This event was jam-packed and extremely well-received by everybody who attended it. As what I said, average demos and good presentations by MS folks were really something to cheer about. Any launch event is considered as successful if it achieves its goal to excite users with its cutting edge technology; just like this event that left a very deep impression on me. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Author Visit, SQLAuthority News, T SQL, Technology Tagged: PASS, SQLPASS

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  • Surface Review from Canadian Guy Who Didn&rsquo;t Go To Build

    - by D'Arcy Lussier
    I didn’t go to Build last week, opted to stay home and go trick-or-treating with my daughters instead. I had many friends that did go however, and I was able to catch up with James Chambers last night to hear about the conference and play with his Surface RT and Nokia 920 WP8 devices. I’ve been using Windows 8 for a while now, so I’m not going to comment on OS features – lots of posts out there on that already. Let me instead comment on the hardware itself. Size and Weight The size of the tablet was awesome. The Windows 8 tablet I’m using to reference this against is the one from Build 2011 (Samsung model) we received as well as my iPad. The Surface RT was taller and slightly heavier than the iPad, but smaller and lighter than the Samsung Win 8 tablet. I still don’t prefer the default wide-screen format, but the Surface RT is much more usable even when holding it by the long edge than the Samsung. Build Quality No issues with the build quality, it seemed very solid. But…y’know, people have been going on about how the Surface RT materials are so much better than the plastic feeling models Samsung and others put out. I didn’t really notice *that* much difference in that regard with the Surface RT. Interesting feature I didn’t expect – the Windows button on the device is touch-sensitive, not a mechanical one. I didn’t try video or anything, so I can’t comment on the media experience. The kickstand is a great feature, and the way the Surface RT connects to the combo case/keyboard touchcover is very slick while being incredibly simple. What About That Touch Cover Keyboard? So first, kudos to Microsoft on the touch cover! This thing was insanely responsive (including the trackpad) and really delivered on the thinness I was expecting. With that said, and remember this is with very limited use, I would probably go with the Type Cover instead of the Touch Cover. The difference is buttons. The Touch Cover doesn’t actually have “buttons” on the keyboard – hence why its a “touch” cover. You tap on a key to type it. James tells me after a while you get used to it and you can type very fast. For me, I just prefer the tactile feeling of a button being pressed/depressed. But still – typing on the touch case worked very well. Would I Buy One? So after playing with it, did I cry out in envy and rage that I wasn’t able to get one of these machines? Did I curse my decision to collect Halloween candy with my kids instead of being at Build getting hardware? Well – no. Even with the keyboard, the Surface RT is not a business laptop replacement device. While Office does come included, you can’t install any other applications outside of Windows Store Apps. This might be limiting depending on what other applications you need to have available on your computer. Surface RT is a great personal computing device, as long as you’re not already invested in a competing ecosystem. I’ve heard people make statements that they’re going to replace all the iPads in their homes with Surface tablets. In my home, that’s not feasible – my wife and daughters have amassed quite a collection of games via iTunes. We also buy all our music via iTunes as well, so even with the XBox streaming music service now available we’re still tied quite tightly to iTunes. So who is the Surface RT for? In my mind, if you’re looking for a solid, compact device that provides basic business functionality (read: email) or if you have someone that needs a very simple to use computer for email, web browsing, etc., then Surface RT is a great option. For me, I’m waiting on the Samsung Ativ Smart PC Pro and am curious to see what changes the Surface Pro will come with.

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  • Developer Training – Importance and Significance – Part 1

    - by pinaldave
    Developer Training - Importance and Significance - Part 1 Developer Training – Employee Morals and Ethics – Part 2 Developer Training – Difficult Questions and Alternative Perspective - Part 3 Developer Training – Various Options for Developer Training – Part 4 Developer Training – A Conclusive Summary- Part 5 Can anyone remember their final day of schooling?  This is probably a silly question because – of course you can!  Many people mark this as the most exciting, happiest day of their life.  It marks the end of testing, the end of following rules set by teachers, and the beginning of finally being able to earn money and work in your chosen field. Beginning in Real World However, many former-students will be disappointed to find out that once they become employees, learning is not over.  Many companies are discovering the importance and benefits to training their employees.  You can breathe a sigh of relief, though, because much for this kind of training there are not usually tests! We often think that we go to school for our younger years so that we do all our learning all at once, and then for the rest of our lives we use that knowledge.  But in so many cases, but especially for developers, the opposite is true.  It takes many years of schools to learn the basics of a field, and then our careers are spent learning to become experts. For this, and so many other reasons, training is very important.  Example one: developer training leads to better employees.  A company is only as good as the people it employs, and one way to ensure that you have employed the right candidate is through training.  Training can take a regular “stone” and polish it into a “diamond.”  Employees who have been well-trained will be better at their jobs and produce a better product. Most Expensive Resource Did you know that one of the most expensive operating costs for any company is not buying goods, or advertising, but its employees – especially having to hire new employees.  Bringing in new people, getting them up to speed, and providing them with perks to attract them to a company is a huge cost for companies.  So employee retention – keep the employees you already have, and keeping them happy – is incredibly important from a business aspect.  And research shows that a well-trained employee is a happy employee.  They feel more confident in their job, happier with their position, and more cared-about – and therefore less likely to leave in search of a better job.  Employee training leads to better retention. Good Moral On the subject of keeping employees happy in order to keep them at a company, the complement to that research shows that happier employees are more efficient and overall better at their jobs.  You don’t have to be a scientist to figure out why this is true.  An employee who feel that his company cares about him and his educational future will work harder for the company.  He or she will put in that extra hour during the busy season that makes all the difference in the end.  Good morale is good for the company. If good morale is better for the company, you know that it goes hand-in-hand with something even better – better efficiency.  An employee who is well trained obviously knows more about their job and all the technical aspects.  That means when a problem crops up – and they inevitably do – this employee will be well-equipped to deal with that problem with fewer problems, and no need to go searching for help from higher up.  When employees are well trained, companies run more smoothly. A Better Product Of course, all of these “pros” for employee training are leading up to the one thing that companies truly care about – a better product.  We have shown that employees who have been trained to be competitive in the market are happier at the company, they are more efficient, and their morale is better.  The overall result is that the company’s product – whether it is a database, piece of equipment, or even a physical good – is better.  And a better product will always be more competitive on the market. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Developer Training, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • SQL SERVER – Auto Complete and Format T-SQL Code – Devart SQL Complete

    - by pinaldave
    Some people call it laziness, some will call it efficiency, some think it is the right thing to do. At any rate, tools are meant to make a job easier, and I like to use various tools. If we consider the history of the world, if we all wanted to keep traditional practices, we would have never invented the wheel.  But as time progressed, people wanted convenience and efficiency, which then led to laziness. Wanting a more efficient way to do something is not inherently lazy.  That’s how I see any efficiency tools. A few days ago I found Devart SQL Complete.  It took less than a minute to install, and after installation it just worked without needing any tweaking.  Once I started using it I was impressed with how fast it formats SQL code – you can write down any terms or even copy and paste.  You can start typing right away, and it will complete keywords, object names, and fragmentations. It completes statement expressions.  How many times do we write insert, update, delete?  Take this example: to alter a stored procedure name, we don’t remember the code written in it, you have to write it over again, or go back to SQL Server Studio Manager to create and alter which is very difficult.  With SQL Complete , you can write “alter stored procedure,” and it will finish it for you, and you can modify as needed. I love to write code, and I love well-written code.  When I am working with clients, and I find people whose code have not been written properly, I feel a little uncomfortable.  It is difficult to deal with code that is in the wrong case, with no line breaks, no white spaces, improper indents, and no text wrapping.  The worst thing to encounter is code that goes all the way to the right side, and you have to scroll a million times because there are no breaks or indents.  SQL Complete will take care of this for you – if a developer is too lazy for proper formatting, then Devart’s SQL formatter tool will make them better, not lazier. SQL Management Studio gives information about your code when you hover your mouse over it, however SQL Complete goes further in it, going into the work table, and the current rate idea, too. It gives you more information about the parameters; and last but not least, it will just take you to the help file of code navigation.  It will open object explorer in a document viewer.  You can start going through the various properties of your code – a very important thing to do. Here are are interesting Intellisense examples: 1) We are often very lazy to expand *however, when we are using SQL Complete we can just mouse over the * and it will give us all the the column names and we can select the appropriate columns. 2) We can put the cursor after * and it will give us option to expand it to all the column names by pressing the Tab key. 3) Here is one more Intellisense feature I really liked it. I always alias my tables and I always select the alias with special logic. When I was using SQL Complete I selected just a tablename (without schema name) and…(just like below image) … and it autocompleted the schema and alias name (the way I needed it). I believe using SQL Complete we can work faster.  It supports all versions of SQL Server, and works SQL formatting.  Many businesses perform code review and have code standards, so why not use an efficiency tool on everyone’s computer and make sure the code is written correctly from the first time?  If you’re interested in this tool, there are free editions available.  If you like it, you can buy it.  I bought it because it works.  I love it, and I want to hear all your opinions on it, too. You can get the product for FREE.  Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQL Utility, T SQL, Technology

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  • Something for the weekend - Whats the most complex query?

    - by simonsabin
    Whenever I teach about SQL Server performance tuning I try can get across the message that there is no such thing as a table. Does that sound odd, well it isn't, trust me. Rather than tables you need to consider structures. You have 1. Heaps 2. Indexes (b-trees) Some people split indexes in two, clustered and non-clustered, this I feel confuses the situation as people associate clustered indexes with sorting, but don't associate non clustered indexes with sorting, this is wrong. Clustered and non-clustered indexes are the same b-tree structure(and even more so with SQL 2005) with the leaf pages sorted in a linked list according to the keys of the index.. The difference is that non clustered indexes include in their structure either, the clustered key(s), or the row identifier for the row in the table (see http://sqlblog.com/blogs/kalen_delaney/archive/2008/03/16/nonclustered-index-keys.aspx for more details). Beyond that they are the same, they have key columns which are stored on the root and intermediary pages, and included columns which are on the leaf level. The reason this is important is that this is how the optimiser sees the world, this means it can use any of these structures to resolve your query. Even if your query only accesses one table, the optimiser can access multiple structures to get your results. One commonly sees this with a non-clustered index scan and then a key lookup (clustered index seek), but importantly it's not restricted to just using one non-clustered index and the clustered index or heap, and that's the challenge for the weekend. So the challenge for the weekend is to produce the most complex single table query. For those clever bods amongst you that are thinking, great I will just use lots of xquery functions, sorry these are the rules. 1. You have to use a table from AdventureWorks (2005 or 2008) 2. You can add whatever indexes you like, but you must document these 3. You cannot use XQuery, Spatial, HierarchyId, Full Text or any open rowset function. 4. You can only reference your table once, i..e a FROM clause with ONE table and no JOINs 5. No Sub queries. The aim of this is to show how the optimiser can use multiple structures to build the results of a query and to also highlight why the optimiser is doing that. How many structures can you get the optimiser to use? As an example create these two indexes on AdventureWorks2008 create index IX_Person_Person on Person.Person (lastName, FirstName,NameStyle,PersonType) create index IX_Person_Person on Person.Person(BusinessentityId,ModifiedDate)with drop_existing    select lastName, ModifiedDate   from Person.Person  where LastName = 'Smith' You will see that the optimiser has decided to not access the underlying clustered index of the table but to use two indexes above to resolve the query. This highlights how the optimiser considers all storage structures, clustered indexes, non clustered indexes and heaps when trying to resolve a query. So are you up to the challenge for the weekend to produce the most complex single table query? The prize is a pdf version of a popular SQL Server book, or a physical book if you live in the UK.  

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  • T-SQL Improvements And Data Types in ms sql 2008

    - by Aamir Hasan
     Microsoft SQL Server 2008 is a new version released in the first half of 2008 introducing new properties and capabilities to SQL Server product family. All these new and enhanced capabilities can be defined as the classic words like secure, reliable, scalable and manageable. SQL Server 2008 is secure. It is reliable. SQL2008 is scalable and is more manageable when compared to previous releases. Now we will have a look at the features that are making MS SQL Server 2008 more secure, more reliable, more scalable, etc. in details.Microsoft SQL Server 2008 provides T-SQL enhancements that improve performance and reliability. Itzik discusses composable DML, the ability to declare and initialize variables in the same statement, compound assignment operators, and more reliable object dependency information. Table-Valued ParametersInserts into structures with 1-N cardinality problematicOne order -> N order line items"N" is variable and can be largeDon't want to force a new order for every 20 line itemsOne database round-trip / line item slows things downNo ARRAY data type in SQL ServerXML composition/decomposition used as an alternativeTable-valued parameters solve this problemTable-Valued ParametersSQL Server has table variablesDECLARE @t TABLE (id int);SQL Server 2008 adds strongly typed table variablesCREATE TYPE mytab AS TABLE (id int);DECLARE @t mytab;Parameters must use strongly typed table variables Table Variables are Input OnlyDeclare and initialize TABLE variable  DECLARE @t mytab;  INSERT @t VALUES (1), (2), (3);  EXEC myproc @t;Procedure must declare variable READONLY  CREATE PROCEDURE usetable (    @t mytab READONLY ...)  AS    INSERT INTO lineitems SELECT * FROM @t;    UPDATE @t SET... -- no!T-SQL Syntax EnhancementsSingle statement declare and initialize  DECLARE @iint = 4;Compound Assignment Operators  SET @i += 1;Row constructors  DECLARE @t TABLE (id int, name varchar(20));  INSERT INTO @t VALUES    (1, 'Fred'), (2, 'Jim'), (3, 'Sue');Grouping SetsGrouping Sets allow multiple GROUP BY clauses in a single SQL statementMultiple, arbitrary, sets of subtotalsSingle read pass for performanceNested subtotals provide ever better performanceGrouping Sets are an ANSI-standardCOMPUTE BY is deprecatedGROUPING SETS, ROLLUP, CUBESQL Server 2008 - ANSI-syntax ROLLUP and CUBEPre-2008 non-ANSI syntax is deprecatedWITH ROLLUP produces n+1 different groupings of datawhere n is the number of columns in GROUP BYWITH CUBE produces 2^n different groupingswhere n is the number of columns in GROUP BYGROUPING SETS provide a "halfway measure"Just the number of different groupings you needGrouping Sets are visible in query planGROUPING_ID and GROUPINGGrouping Sets can produce non-homogeneous setsGrouping set includes NULL values for group membersNeed to distinguish by grouping and NULL valuesGROUPING (column expression) returns 0 or 1Is this a group based on column expr. or NULL value?GROUPING_ID (a,b,c) is a bitmaskGROUPING_ID bits are set based on column expressions a, b, and cMERGE StatementMultiple set operations in a single SQL statementUses multiple sets as inputMERGE target USING source ON ...Operations can be INSERT, UPDATE, DELETEOperations based onWHEN MATCHEDWHEN NOT MATCHED [BY TARGET] WHEN NOT MATCHED [BY SOURCE]More on MERGEMERGE statement can reference a $action columnUsed when MERGE used with OUTPUT clauseMultiple WHEN clauses possible For MATCHED and NOT MATCHED BY SOURCEOnly one WHEN clause for NOT MATCHED BY TARGETMERGE can be used with any table sourceA MERGE statement causes triggers to be fired onceRows affected includes total rows affected by all clausesMERGE PerformanceMERGE statement is transactionalNo explicit transaction requiredOne Pass Through TablesAt most a full outer joinMatching rows = when matchedLeft-outer join rows = when not matched by targetRight-outer join rows = when not matched by sourceMERGE and DeterminismUPDATE using a JOIN is non-deterministicIf more than one row in source matches ON clause, either/any row can be used for the UPDATEMERGE is deterministicIf more than one row in source matches ON clause, its an errorKeeping Track of DependenciesNew dependency views replace sp_dependsViews are kept in sync as changes occursys.dm_sql_referenced_entitiesLists all named entities that an object referencesExample: which objects does this stored procedure use?sys.dm_sql_referencing_entities 

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  • SQL SERVER – Attach mdf file without ldf file in Database

    - by pinaldave
    Background Story: One of my friends recently called up and asked me if I had spare time to look at his database and give him a performance tuning advice. Because I had some free time to help him out, I said yes. I asked him to send me the details of his database structure and sample data. He said that since his database is in a very early stage and is small as of the moment, so he told me that he would like me to have a complete database. My response to him was “Sure! In that case, take a backup of the database and send it to me. I will restore it into my computer and play with it.” He did send me his database; however, his method made me write this quick note here. Instead of taking a full backup of the database and sending it to me, he sent me only the .mdf (primary database file). In fact, I asked for a complete backup (I wanted to review file groups, files, as well as few other details).  Upon calling my friend,  I found that he was not available. Now,  he left me with only a .mdf file. As I had some extra time, I decided to checkout his database structure and get back to him regarding the full backup, whenever I can get in touch with him again. Technical Talk: If the database is shutdown gracefully and there was no abrupt shutdown (power outrages, pulling plugs to machines, machine crashes or any other reasons), it is possible (there’s no guarantee) to attach .mdf file only to the server. Please note that there can be many more reasons for a database that is not getting attached or restored. In my case, the database had a clean shutdown and there were no complex issues. I was able to recreate a transaction log file and attached the received .mdf file. There are multiple ways of doing this. I am listing all of them here. Before using any of them, please consult the Domain Expert in your company or industry. Also, never attempt this on live/production server without the presence of a Disaster Recovery expert. USE [master] GO -- Method 1: I use this method EXEC sp_attach_single_file_db @dbname='TestDb', @physname=N'C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\DATA\TestDb.mdf' GO -- Method 2: CREATE DATABASE TestDb ON (FILENAME = N'C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\DATA\TestDb.mdf') FOR ATTACH_REBUILD_LOG GO Method 2: If one or more log files are missing, they are recreated again. There is one more method which I am demonstrating here but I have not used myself before. According to Book Online, it will work only if there is one log file that is missing. If there are more than one log files involved, all of them are required to undergo the same procedure. -- Method 3: CREATE DATABASE TestDb ON ( FILENAME = N'C:\Program Files\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\DATA\TestDb.mdf') FOR ATTACH GO Please read the Book Online in depth and consult DR experts before working on the production server. In my case, the above syntax just worked fine as the database was clean when it was detached. Feel free to write your opinions and experiences for it will help the IT community to learn more from your suggestions and skills. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, Readers Question, SQL, SQL Authority, SQL Backup and Restore, SQL Data Storage, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • SQL SERVER – Merge Operations – Insert, Update, Delete in Single Execution

    - by pinaldave
    This blog post is written in response to T-SQL Tuesday hosted by Jorge Segarra (aka SQLChicken). I have been very active using these Merge operations in my development. However, I have found out from my consultancy work and friends that these amazing operations are not utilized by them most of the time. Here is my attempt to bring the necessity of using the Merge Operation to surface one more time. MERGE is a new feature that provides an efficient way to do multiple DML operations. In earlier versions of SQL Server, we had to write separate statements to INSERT, UPDATE, or DELETE data based on certain conditions; however, at present, by using the MERGE statement, we can include the logic of such data changes in one statement that even checks when the data is matched and then just update it, and similarly, when the data is unmatched, it is inserted. One of the most important advantages of MERGE statement is that the entire data are read and processed only once. In earlier versions, three different statements had to be written to process three different activities (INSERT, UPDATE or DELETE); however, by using MERGE statement, all the update activities can be done in one pass of database table. I have written about these Merge Operations earlier in my blog post over here SQL SERVER – 2008 – Introduction to Merge Statement – One Statement for INSERT, UPDATE, DELETE. I was asked by one of the readers that how do we know that this operator was doing everything in single pass and was not calling this Merge Operator multiple times. Let us run the same example which I have used earlier; I am listing the same here again for convenience. --Let’s create Student Details and StudentTotalMarks and inserted some records. USE tempdb GO CREATE TABLE StudentDetails ( StudentID INTEGER PRIMARY KEY, StudentName VARCHAR(15) ) GO INSERT INTO StudentDetails VALUES(1,'SMITH') INSERT INTO StudentDetails VALUES(2,'ALLEN') INSERT INTO StudentDetails VALUES(3,'JONES') INSERT INTO StudentDetails VALUES(4,'MARTIN') INSERT INTO StudentDetails VALUES(5,'JAMES') GO CREATE TABLE StudentTotalMarks ( StudentID INTEGER REFERENCES StudentDetails, StudentMarks INTEGER ) GO INSERT INTO StudentTotalMarks VALUES(1,230) INSERT INTO StudentTotalMarks VALUES(2,255) INSERT INTO StudentTotalMarks VALUES(3,200) GO -- Select from Table SELECT * FROM StudentDetails GO SELECT * FROM StudentTotalMarks GO -- Merge Statement MERGE StudentTotalMarks AS stm USING (SELECT StudentID,StudentName FROM StudentDetails) AS sd ON stm.StudentID = sd.StudentID WHEN MATCHED AND stm.StudentMarks > 250 THEN DELETE WHEN MATCHED THEN UPDATE SET stm.StudentMarks = stm.StudentMarks + 25 WHEN NOT MATCHED THEN INSERT(StudentID,StudentMarks) VALUES(sd.StudentID,25); GO -- Select from Table SELECT * FROM StudentDetails GO SELECT * FROM StudentTotalMarks GO -- Clean up DROP TABLE StudentDetails GO DROP TABLE StudentTotalMarks GO The Merge Join performs very well and the following result is obtained. Let us check the execution plan for the merge operator. You can click on following image to enlarge it. Let us evaluate the execution plan for the Table Merge Operator only. We can clearly see that the Number of Executions property suggests value 1. Which is quite clear that in a single PASS, the Merge Operation completes the operations of Insert, Update and Delete. I strongly suggest you all to use this operation, if possible, in your development. I have seen this operation implemented in many data warehousing applications. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Joins, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: Merge

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  • Logging connection strings

    If you some of the dynamic features of SSIS such as package configurations or property expressions then sometimes trying to work out were your connections are pointing can be a bit confusing. You will work out in the end but it can be useful to explicitly log this information so that when things go wrong you can just review the logs. You may wish to develop this idea further and encapsulate such logging into a custom task, but for now lets keep it simple and use the Script Task. The Script Task code below will raise an Information event showing the name and connection string for a connection. Imports System Imports Microsoft.SqlServer.Dts.Runtime Public Class ScriptMain Public Sub Main() Dim fireAgain As Boolean ' Get the connection string, we need to know the name of the connection Dim connectionName As String = "My OLE-DB Connection" Dim connectionString As String = Dts.Connections(connectionName).ConnectionString ' Format the message and log it via an information event Dim message As String = String.Format("Connection ""{0}"" has a connection string of ""{1}"".", _ connectionName, connectionString) Dts.Events.FireInformation(0, "Information", message, Nothing, 0, fireAgain) Dts.TaskResult = Dts.Results.Success End Sub End Class Building on that example it is probably more flexible to log all connections in a package as shown in the next example. Imports System Imports Microsoft.SqlServer.Dts.Runtime Public Class ScriptMain Public Sub Main() Dim fireAgain As Boolean ' Loop through all connections in the package For Each connection As ConnectionManager In Dts.Connections ' Get the connection string and log it via an information event Dim message As String = String.Format("Connection ""{0}"" has a connection string of ""{1}"".", _ connection.Name, connection.ConnectionString) Dts.Events.FireInformation(0, "Information", message, Nothing, 0, fireAgain) Next Dts.TaskResult = Dts.Results.Success End Sub End Class By using the Information event it makes it readily available in the designer, for example the Visual Studio Output window (Ctrl+Alt+O) or the package designer Execution Results tab, and also allows you to readily control the logging by choosing which events to log in the normal way. Now before somebody starts commenting that this is a security risk, I would like to highlight good practice for building connection managers. Firstly the Password property, or any other similar sensitive property is always defined as write-only, and secondly the connection string property only uses the public properties to assemble the connection string value when requested. In other words the connection string will never contain the password. I have seen a couple of cases where this is not true, but that was just bad development by third-parties, you won’t find anything like that in the box from Microsoft.   Whilst writing this code it made me wish that there was a custom log entry that you could just turn on that did this for you, but alas connection managers do not even seem to support custom events. It did however remind me of a very useful event that is often overlooked and fits rather well alongside connection string logging, the Execute SQL Task’s custom ExecuteSQLExecutingQuery event. To quote the help reference Custom Messages for Logging - Provides information about the execution phases of the SQL statement. Log entries are written when the task acquires connection to the database, when the task starts to prepare the SQL statement, and after the execution of the SQL statement is completed. The log entry for the prepare phase includes the SQL statement that the task uses. It is the last part that is so useful, how often have you used an expression to derive a SQL statement and you want to log that to make sure the correct SQL is being returned? You need to turn it one, by default no custom log events are captured, but I’ll refer you to a walkthrough on setting up the logging for ExecuteSQLExecutingQuery by Jamie.

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  • SQL SERVER – Reducing CXPACKET Wait Stats for High Transactional Database

    - by pinaldave
    While engaging in a performance tuning consultation for a client, a situation occurred where they were facing a lot of CXPACKET Waits Stats. The client asked me if I could help them reduce this huge number of wait stats. I usually receive this kind of request from other client as well, but the important thing to understand is whether this question has any merits or benefits, or not. Before we continue the resolution, let us understand what CXPACKET Wait Stats are. The official definition suggests that CXPACKET Wait Stats occurs when trying to synchronize the query processor exchange iterator. You may consider lowering the degree of parallelism if a conflict concerning this wait type develops into a problem. (from BOL) In simpler words, when a parallel operation is created for SQL Query, there are multiple threads for a single query. Each query deals with a different set of the data (or rows). Due to some reasons, one or more of the threads lag behind, creating the CXPACKET Wait Stat. Threads which came first have to wait for the slower thread to finish. The Wait by a specific completed thread is called CXPACKET Wait Stat. Note that CXPACKET Wait is done by completed thread and not the one which are unfinished. “Note that not all the CXPACKET wait types are bad. You might experience a case when it totally makes sense. There might also be cases when this is also unavoidable. If you remove this particular wait type for any query, then that query may run slower because the parallel operations are disabled for the query.” Now let us see what the best practices to reduce the CXPACKET Wait Stats are. The suggestions, with which you will find that if you search online through the browser, would play a major role as and might be asked about their jobs In addition, might tell you that you should set ‘maximum degree of parallelism’ to 1. I do agree with these suggestions, too; however, I think this is not the final resolutions. As soon as you set your entire query to run on single CPU, you will get a very bad performance from the queries which are actually performing okay when using parallelism. The best suggestion to this is that you set ‘the maximum degree of parallelism’ to a lower number or 1 (be very careful with this – it can create more problems) but tune the queries which can be benefited from multiple CPU’s. You can use query hint OPTION (MAXDOP 0) to run the server to use parallelism. Here is the two-quick script which helps to resolve these issues: Change MAXDOP at Server Level EXEC sys.sp_configure N'max degree of parallelism', N'1' GO RECONFIGURE WITH OVERRIDE GO Run Query with all the CPU (using parallelism) USE AdventureWorks GO SELECT * FROM Sales.SalesOrderDetail ORDER BY ProductID OPTION (MAXDOP 0) GO Below is the blog post which will help you to find all the parallel query in your server. SQL SERVER – Find Queries using Parallelism from Cached Plan Please note running Queries in single CPU may worsen your performance and it is not recommended at all. Infect this can be very bad advise. I strongly suggest that you identify the queries which are offending and tune them instead of following any other suggestions. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: SQL, SQL Authority, SQL Optimization, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, SQL White Papers, SQLAuthority News, T SQL, Technology

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  • SQL SERVER – 2012 – All Download Links in Single Page – SQL Server 2012

    - by pinaldave
    SQL Server 2012 RTM is just announced and recently I wrote about all the SQL Server 2012 Certification on single page. As a feedback, I received suggestions to have a single page where everything about SQL Server 2012 is listed. I will keep this page updated as new updates are announced. Microsoft SQL Server 2012 Evaluation Microsoft SQL Server 2012 enables a cloud-ready information platform that will help organizations unlock breakthrough insights across the organization. Microsoft SQL Server 2012 Express Microsoft SQL Server 2012 Express is a powerful and reliable free data management system that delivers a rich and reliable data store for lightweight Web Sites and desktop applications. Microsoft SQL Server 2012 Feature Pack The Microsoft SQL Server 2012 Feature Pack is a collection of stand-alone packages which provide additional value for Microsoft SQL Server 2012. Microsoft SQL Server 2012 Report Builder Report Builder provides a productive report-authoring environment for IT professionals and power users. It supports the full capabilities of SQL Server 2012 Reporting Services. Microsoft SQL Server 2012 Master Data Services Add-in For Microsoft Excel The Master Data Services Add-in for Excel gives multiple users the ability to update master data in a familiar tool without compromising the data’s integrity in Master Data Services. Microsoft SQL Server 2012 Performance Dashboard Reports The SQL Server 2012 Performance Dashboard Reports are Reporting Services report files designed to be used with the Custom Reports feature of SQL Server Management Studio. Microsoft SQL Server 2012 PowerPivot for Microsoft Excel® 2010 Microsoft PowerPivot for Microsoft Excel 2010 provides ground-breaking technology; fast manipulation of large data sets, streamlined integration of data, and the ability to effortlessly share your analysis through Microsoft SharePoint. Microsoft SQL Server 2012 Reporting Services Add-in for Microsoft SharePoint Technologies 2010 The SQL Server 2012 Reporting Services Add-in for Microsoft SharePoint 2010 technologies allows you to integrate your reporting environment with the collaborative SharePoint 2010 experience. Microsoft SQL Server 2012 Semantic Language Statistics The Semantic Language Statistics Database is a required component for the Statistical Semantic Search feature in Microsoft SQL Server 2012 Semantic Language Statistics. Microsoft ®SQL Server 2012 FileStream Driver – Windows Logo Certification Catalog file for Microsoft SQL Server 2012 FileStream Driver that is certified for WindowsServer 2008 R2. It meets Microsoft standards for compatibility and recommended practices with the Windows Server 2008 R2 operating systems. Microsoft SQL Server StreamInsight 2.0 Microsoft StreamInsight is Microsoft’s Complex Event Processing technology to help businesses create event-driven applications and derive better insights by correlating event streams from multiple sources with near-zero latency. Microsoft JDBC Driver 4.0 for SQL Server Download the Microsoft JDBC Driver 4.0 for SQL Server, a Type 4 JDBC driver that provides database connectivity through the standard JDBC application program interfaces (APIs) available in Java Platform, Enterprise Edition 5 and 6. Data Quality Services Performance Best Practices Guide This guide focuses on a set of best practices for optimizing performance of Data Quality Services (DQS). Microsoft Drivers 3.0 for SQL Server for PHP The Microsoft Drivers 3.0 for SQL Server for PHP provide connectivity to Microsoft SQLServer from PHP applications. Product Documentation for Microsoft SQL Server 2012 for firewall and proxy restricted environments The Microsoft SQL Server 2012 setup installs only the Help Viewer…install any documentation. All of the SQL Server documentation is available online. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • SQL SERVER – SOS_SCHEDULER_YIELD – Wait Type – Day 8 of 28

    - by pinaldave
    This is a very interesting wait type and quite often seen as one of the top wait types. Let us discuss this today. From Book On-Line: Occurs when a task voluntarily yields the scheduler for other tasks to execute. During this wait the task is waiting for its quantum to be renewed. SOS_SCHEDULER_YIELD Explanation: SQL Server has multiple threads, and the basic working methodology for SQL Server is that SQL Server does not let any “runnable” thread to starve. Now let us assume SQL Server OS is very busy running threads on all the scheduler. There are always new threads coming up which are ready to run (in other words, runnable). Thread management of the SQL Server is decided by SQL Server and not the operating system. SQL Server runs on non-preemptive mode most of the time, meaning the threads are co-operative and can let other threads to run from time to time by yielding itself. When any thread yields itself for another thread, it creates this wait. If there are more threads, it clearly indicates that the CPU is under pressure. You can fun the following DMV to see how many runnable task counts there are in your system. SELECT scheduler_id, current_tasks_count, runnable_tasks_count, work_queue_count, pending_disk_io_count FROM sys.dm_os_schedulers WHERE scheduler_id < 255 GO If you notice a two-digit number in runnable_tasks_count continuously for long time (not once in a while), you will know that there is CPU pressure. The two-digit number is usually considered as a bad thing; you can read the description of the above DMV over here. Additionally, there are several other counters (%Processor Time and other processor related counters), through which you can refer to so you can validate CPU pressure along with the method explained above. Reducing SOS_SCHEDULER_YIELD wait: This is the trickiest part of this procedure. As discussed, this particular wait type relates to CPU pressure. Increasing more CPU is the solution in simple terms; however, it is not easy to implement this solution. There are other things that you can consider when this wait type is very high. Here is the query where you can find the most expensive query related to CPU from the cache Note: The query that used lots of resources but is not cached will not be caught here. SELECT SUBSTRING(qt.TEXT, (qs.statement_start_offset/2)+1, ((CASE qs.statement_end_offset WHEN -1 THEN DATALENGTH(qt.TEXT) ELSE qs.statement_end_offset END - qs.statement_start_offset)/2)+1), qs.execution_count, qs.total_logical_reads, qs.last_logical_reads, qs.total_logical_writes, qs.last_logical_writes, qs.total_worker_time, qs.last_worker_time, qs.total_elapsed_time/1000000 total_elapsed_time_in_S, qs.last_elapsed_time/1000000 last_elapsed_time_in_S, qs.last_execution_time, qp.query_plan FROM sys.dm_exec_query_stats qs CROSS APPLY sys.dm_exec_sql_text(qs.sql_handle) qt CROSS APPLY sys.dm_exec_query_plan(qs.plan_handle) qp ORDER BY qs.total_worker_time DESC -- CPU time You can find the most expensive queries that are utilizing lots of CPU (from the cache) and you can tune them accordingly. Moreover, you can find the longest running query and attempt to tune them if there is any processor offending code. Additionally, pay attention to total_worker_time because if that is also consistently higher, then  the CPU under too much pressure. You can also check perfmon counters of compilations as they tend to use good amount of CPU. Index rebuild is also a CPU intensive process but we should consider that main cause for this query because that is indeed needed on high transactions OLTP system utilized to reduce fragmentations. Note: The information presented here is from my experience and there is no way that I claim it to be accurate. I suggest reading Book OnLine for further clarification. All of the discussions of Wait Stats in this blog is generic and varies from system to system. It is recommended that you test this on a development server before implementing it to a production server. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, SQL Wait Stats, SQL Wait Types, T SQL, Technology

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  • Oracle SQL Developer Data Modeler: What Tables Aren’t In At Least One SubView?

    - by thatjeffsmith
    Organizing your data model makes the information easier to consume. One of the organizational tools provided by Oracle SQL Developer Data Modeler is the ‘SubView.’ In a nutshell, a SubView is a subset of your model. The Challenge: I’ve just created a model which represents my entire ____________ application. We’ll call it ‘residential lending.’ Instead of having all 100+ tables in a single model diagram, I want to break out the tables by module, e.g. appraisals, credit reports, work histories, customers, etc. I’ve spent several hours breaking out the tables to one or more SubViews, but I think i may have missed a few. Is there an easy way to see what tables aren’t in at least ONE subview? The Answer Yes, mostly. The mostly comes about from the way I’m going to accomplish this task. It involves querying the SQL Developer Data Modeler Reporting Schema. So if you don’t have the Reporting Schema setup, you’ll need to do so. Got it? Good, let’s proceed. Before you start querying your Reporting Schema, you might need a data model for the actual reporting schema…meta-meta data! You could reverse engineer the data modeler reporting schema to a new data model, or you could just reference the PDFs in \datamodeler\reports\Reporting Schema diagrams directory. Here’s a hint, it’s THIS one The Query Well, it’s actually going to be at least 2 queries. We need to get a list of distinct designs stored in your repository. For giggles, I’m going to get a listing including each version of the model. So I can query based on design and version, or in this case, timestamp of when it was added to the repository. We’ll get that from the DMRS_DESIGNS table: SELECT DISTINCT design_name, design_ovid, date_published FROM DMRS_designs Then I’m going to feed the design_ovid, down to a subquery for my child report. select name, count(distinct diagram_id) from DMRS_DIAGRAM_ELEMENTS where design_ovid = :dESIGN_OVID and type = 'Table' group by name having count(distinct diagram_id) < 2 order by count(distinct diagram_id) desc Each diagram element has an entry in this table, so I need to filter on type=’Table.’ Each design has AT LEAST one diagram, the master diagram. So any relational table in this table, only having one listing means it’s not in any SubViews. If you have overloaded object names, which is VERY possible, you’ll want to do the report off of ‘OBJECT_ID’, but then you’ll need to correlate that to the NAME, as I doubt you’re so intimate with your designs that you recognize the GUIDs So I’m going to cheat and just stick with names, but I think you get the gist. My Model Of my almost 90 tables, how many of those have I not added to at least one SubView? Now let’s run my report! Voila! My ‘BEER2′ table isn’t in any SubView! It says ’1′ because the main model diagram counts as a view. So if the count came back as ’2′, that would mean the table was in the main model diagram and in 1 SubView diagram. And I know what you’re thinking, what kind of residential lending program would have a table called ‘BEER2?’ Let’s just say, that my business model has some kinks to work out!

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  • What is Agile Modeling and why do I need it?

    What is Agile Modeling and why do I need it? Agile Modeling is an add-on to existing agile methodologies like Extreme programming (XP) and Rational Unified Process (RUP). Agile Modeling enables developers to develop a customized software development process that actually meets their current development needs and is flexible enough to adjust in the future. According to Scott Ambler, Agile Modeling consists of five core values that enable this methodology to be effective and light weight Agile Modeling Core Values: Communication Simplicity Feedback Courage Humility Communication is a key component to any successful project. Open communication between stakeholder and the development team is essential when developing new applications or maintaining legacy systems. Agile models promote communication amongst software development teams and stakeholders. Furthermore, Agile Models provide a common understanding of an application for members of a software development team allowing them to have a universal common point of reference. The use of simplicity in Agile Models enables the exploration of new ideas and concepts through the use of basic diagrams instead of investing the time in writing tens or hundreds of lines of code. Feedback in regards to application development is essential. Feedback allows a development team to confirm that the development path is on track. Agile Models allow for quick feedback from shareholders because minimal to no technical expertise is required to understand basic models. Courage is important because you need to make important decisions and be able to change direction by either discarding or refactoring your work when some of your decisions prove inadequate, according to Scott Ambler. As a member of a development team, we must admit that we do not know everything even though some of us think we do. This is where humility comes in to play. Everyone is a knowledge expert in their own specific domain. If you need help with your finances then you would consult an accountant. If you have a problem or are in need of help with a topic why would someone not consult with a subject expert? An effective approach is to assume that everyone involved with your project has equal value and therefore should be treated with respect. Agile Model Characteristics: Purposeful Understandable Sufficiently Accurate Sufficiently Consistent Sufficiently Detailed Provide Positive Value Simple as Possible Just Fulfill Basic Requirements According to Scott Ambler, Agile models are the most effective possible because the time that is invested in the model is just enough effort to complete the job. Furthermore, if a model isn’t good enough yet then additional effort can be invested to get more value out of the model. However if a model is good enough, for the current needs, or surpass the current needs, then any additional work done on the model would be a waste. It is important to remember that good enough is in the eye of the beholder, so this can be tough. In order for Agile Models to work effectively Active Stakeholder need to participation in the modeling process. Finally it is also very important to model with others, this allows for additionally input ensuring that all the shareholders needs are reflected in the models. How can Agile Models be incorporated in to our projects? Agile Models can be incorporated in to our project during the requirement gathering and design phases. As requirements are gathered the models should be updated to incorporate the new project details as they are defined and updated. Additionally, the Agile Models created during the requirement phase can be the bases for the models created during the design phase.  It is important to only add to the model when the changes fit within the agile model characteristics and they do not over complicate the design.

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  • SQL SERVER – Error: Fix – Msg 208 – Invalid object name ‘dbo.backupset’ – Invalid object name ‘dbo.backupfile’

    - by pinaldave
    Just a day before I got a very interesting email. Here is the email (modified a bit to make it relevant to this blog post). “Pinal, We are facing a very strange issue. One of our query  related to backup files and backup set has stopped working suddenly in SSMS. It works fine in application where we have and in the stored procedure but when we have it in our SSMS it gives following error. Msg 208, Level 16, State 1, Line 1 Invalid object name ‘dbo.backupfile’. Here are our queries which we are trying to execute. SELECT name, database_name, backup_size, TYPE, compatibility_level, backup_set_id FROM dbo.backupset; SELECT logical_name, backup_size, file_type FROM dbo.backupfile; This query gives us details related to backupset and backup files when the backup was taken.” When I receive this kind of email, usually I have no answers directly. The claim that it works in stored procedure and in application but not in SSMS gives me no real data. I have requested him to very first check following two things: If he is connected to correct server? His answer was yes. If he has enough permissions? His answer was he was logged in as an admin. This means there was something more to it and I requested him to send me a screenshot of the his SSMS. He promptly sends that to me and as soon as I receive the screen shot I knew what was going on. Before I say anything take a look at the screenshot yourself and see if you can figure out why his queries are not working in SSMS. Just to make your life a bit easy, I have already given a hint in the image. The answer is very simple, the context of the database is master database. To execute above two queries the context of the database has to be msdb. Tables backupset and backupfile belong to the database msdb only. Here are two workaround or solution to above problem: 1) Change context to MSDB Above two queries when they will run as following they will not error out and will give the accurate desired result. USE msdb GO SELECT name, database_name, backup_size, TYPE, compatibility_level, backup_set_id FROM dbo.backupset; SELECT logical_name, backup_size, file_type FROM dbo.backupfile; 2) Prefix the query with msdb There are cases above script used in stored procedure or part of big query, it is not possible to change the context of the whole query to any specific database. Use three part naming convention and prefix them with msdb. SELECT name, database_name, backup_size, TYPE, compatibility_level, backup_set_id FROM msdb.dbo.backupset; SELECT logical_name, backup_size, file_type FROM msdb.dbo.backupfile; Very simple solution but sometime keeps people wondering for an answer. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Error Messages, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Big Data – Buzz Words: What is MapReduce – Day 7 of 21

    - by Pinal Dave
    In yesterday’s blog post we learned what is Hadoop. In this article we will take a quick look at one of the four most important buzz words which goes around Big Data – MapReduce. What is MapReduce? MapReduce was designed by Google as a programming model for processing large data sets with a parallel, distributed algorithm on a cluster. Though, MapReduce was originally Google proprietary technology, it has been quite a generalized term in the recent time. MapReduce comprises a Map() and Reduce() procedures. Procedure Map() performance filtering and sorting operation on data where as procedure Reduce() performs a summary operation of the data. This model is based on modified concepts of the map and reduce functions commonly available in functional programing. The library where procedure Map() and Reduce() belongs is written in many different languages. The most popular free implementation of MapReduce is Apache Hadoop which we will explore tomorrow. Advantages of MapReduce Procedures The MapReduce Framework usually contains distributed servers and it runs various tasks in parallel to each other. There are various components which manages the communications between various nodes of the data and provides the high availability and fault tolerance. Programs written in MapReduce functional styles are automatically parallelized and executed on commodity machines. The MapReduce Framework takes care of the details of partitioning the data and executing the processes on distributed server on run time. During this process if there is any disaster the framework provides high availability and other available modes take care of the responsibility of the failed node. As you can clearly see more this entire MapReduce Frameworks provides much more than just Map() and Reduce() procedures; it provides scalability and fault tolerance as well. A typical implementation of the MapReduce Framework processes many petabytes of data and thousands of the processing machines. How do MapReduce Framework Works? A typical MapReduce Framework contains petabytes of the data and thousands of the nodes. Here is the basic explanation of the MapReduce Procedures which uses this massive commodity of the servers. Map() Procedure There is always a master node in this infrastructure which takes an input. Right after taking input master node divides it into smaller sub-inputs or sub-problems. These sub-problems are distributed to worker nodes. A worker node later processes them and does necessary analysis. Once the worker node completes the process with this sub-problem it returns it back to master node. Reduce() Procedure All the worker nodes return the answer to the sub-problem assigned to them to master node. The master node collects the answer and once again aggregate that in the form of the answer to the original big problem which was assigned master node. The MapReduce Framework does the above Map () and Reduce () procedure in the parallel and independent to each other. All the Map() procedures can run parallel to each other and once each worker node had completed their task they can send it back to master code to compile it with a single answer. This particular procedure can be very effective when it is implemented on a very large amount of data (Big Data). The MapReduce Framework has five different steps: Preparing Map() Input Executing User Provided Map() Code Shuffle Map Output to Reduce Processor Executing User Provided Reduce Code Producing the Final Output Here is the Dataflow of MapReduce Framework: Input Reader Map Function Partition Function Compare Function Reduce Function Output Writer In a future blog post of this 31 day series we will explore various components of MapReduce in Detail. MapReduce in a Single Statement MapReduce is equivalent to SELECT and GROUP BY of a relational database for a very large database. Tomorrow In tomorrow’s blog post we will discuss Buzz Word – HDFS. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Big Data, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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  • SQL SERVER – Transcript of Learning SQL Server Performance: Indexing Basics – Interview of Vinod Kumar by Pinal Dave

    - by pinaldave
    Recently I just wrote a blog post on about Learning SQL Server Performance: Indexing Basics and I received lots of request that if we can share some insight into the course. Here is 200 seconds interview of Vinod Kumar I took right after completing the course. We have few free codes to watch the course, please your comment at http://facebook.com/SQLAuth and we will few of first ones, we will send the code. There are many people who said they would like to read the transcript of the video. Here I have generated the same. Pinal: Vinod, we recently released this course, SQL Server Indexing. It is about performance tuning. So tell me – how do indexes help performance? Vinod: I think what happens in the industry when it comes to performance is that developers and DBAs look at indexes first.  So that’s the first step for any performance tuning exercise, indexing is one of the most critical aspects and it is important to learn it the right way. Pinal: Correct. So what you mean to say is that if you know indexing you can pretty much tune any server and query. Vinod: So I might contradict my false statement now. Indexing is usually a stepping stone but it does not lead you to the end. But it’s good to start with indexing and there are lots of nuances to indexing that you need to understand, like how SQL uses indexing and how performance can improve because of the strategies that you have made. Pinal: But now I’m confused. First you said indexes are good, and then you said that indexes can degrade your performance.  So what is this course about?  I mean how does this course really make an impact? Vinod: Ok -so from the course perspective, what we are trying to do is give you a capsule which gives you a good start. Every journey needs a beginning, you need that first step.  This course is that first step in understanding. This is the most basic, fundamental course that we have tried to attack. This is the fundamentals of indexing, some of the key things that you must know about indexing.   Some of the basics of indexing are lesser known and so I think this course is geared towards each and every one of you out there who wants to understand little bit more about indexing. Pinal: So what I understand is that if I enrolled in this course I will have a minimum understanding about indexing when dealing with performance tuning.  Right? Vinod: Exactly. In this course is we have tried to give you a nice summary. We are talking about clustered indexing, non clustered indexing, too many indexes, too few indexes, over indexing, under indexing, duplicate indexing, columns tune indexing, with SQL Server 2012. There’s lot’s to learn. Pinal: You can see the URL [http://bit.ly/sql-index] of the course on the screen. Go ahead, attend, and let us know what you think about it. Thank you. Vinod: Thank you. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Index, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology, Video

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  • SQL SERVER – What is a Technology Evangelist?

    - by pinaldave
    When you hear that someone is an “evangelist” the first thing that might pop into your mind is the Christian church.  In fact, the term did come from Christianity, and basically means someone who spreads the news about their faith.  In the technology world, the same definition is true. Technology evangelists are individuals who, professionally or in their spare time, spread the news about the latest new products.  Sounds like a salesperson, right?  No they are absolutely different. Salespeople also keep up to date with a large number of people, and like to convince others to buy their product – and some will go to any lengths to sell!  An evangelist, on the other hand, is brutally honest about the product, even if sometimes it means not making a sale.  An evangelist is out there to tell the TRUTH.  A salesperson needs to make sales. An Evangelist offers a Solution independent of Technology used – a Salesperson offers Particular Technology. With this definition in mind, you can probably think of a few technology evangelists you already know.  Maybe it’s a relative or a neighbor, someone who loves keeping up with the latest trends and is always willing to tell you about them if you ask even the simplest question.  And, in fact, they probably are evangelists and don’t even know it.  For a long time, the work of technology evangelism was in the hands of community and community technology leaders. Luckily now various organizations have understood the importance of the community and helping community to reach their goals. This has lead them to create role of “Technology Evangelists”. Let me talk about one of the most famous Evangelist of the SQL Server technology. Technology Evangelist only belongs to technology and above any country, race, location or any other thing. They are dedicated to the technology. Vinod Kumar is such a man, who have given a lot to community. For years he was a Technology Evangelist for Microsoft, and maintained a blog that was dedicated to spreading his enthusiasm for his favorite products.  He is one of the most respected Evangelists in the field, and has done a lot of work to define the job for other professionals. Vinod’s career has since progressed to the Microsoft Technology Center (read his post), but he is continuing to be a strong presence in the evangelism community.  I have a lot of respect for Vinod.  He has done a lot for the community and technology evangelism.  Everybody has dream to serve community the way he does, and he is a great role model for evangelists everywhere. On his blog, Vinod created one of the best descriptions of a Technology Evangelist.  It defined the position and also made the distinction between evangelist and salesperson extremely clear.  I will include the highlights of that list here, because no one can say it better than Vinod: Bundle of energy – Passion is their middle name Wonderful Story tellers Empathy, Trust, Loyalty, Openness, Accessibility and Warmth Technology Enthusiast – Doers Love people, people and more people – Community oriented Unique Style and Leadership qualities !!! Self-Confident, Self-Motivated but a student (To read the full list, see: Evangelism Beyond Borders with Evangelists) His blog is a must-read for anyone interested in technology evangelism as a career or simply a hobby.  His advice about how to gain an audience and become a trusted advisor is the best in the business. I think there is an evangelist in everyone. I, too, consider myself a technology evangelist.  Regular readers of this blog will recognize that I am dedicated to bringing information to the masses, and that I pride myself on being both brutally and honest and giving every product fair consideration. I think there is no better way of saying following subject. “Once an Evangelist – Always an Evangelist!” Reference: Pinal Dave (http://blog.SQLAuthority.com)     Filed under: About Me, Database, MVP, Pinal Dave, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority News, T SQL, Technology Tagged: Evangelist

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  • Silverlight Cream for March 26, 2010 -- #821

    - by Dave Campbell
    In this Issue: Max Paulousky, Christian Schormann, John Papa, Phani Raj, David Anson(-2-, -3-), Brad Abrams(-2-), and Jeff Wilcox(-2-, -3-). Shoutouts: Jeff Wilcox posted his material from mix and some preview TestFramework bits: Unit Testing Silverlight & Windows Phone Applications – talk now online At MIX10, Jeff Wilcox demo'd an app called "Peppermint"... here's the bleeding edge demo: “Peppermint” MIX demo sources Erik Mork and Co. have put out their weekly This Week In Silverlight 3.25.2010 Brad Abrams has all his materials posted for his MIX10 session Mix2010: Search Engine Optimization (SEO) for Microsoft Silverlight... including play-by-play of the demo and all source. Do you use Rooler? Well you should! Watch a video Pete Brown did with Pete Blois on Expression Blend, Windows Phone, Rooler Interested in Silverlight and XNA for WP7? Me too! Michael Klucher has a post outlining the two: Silverlight and XNA Framework Game Development and Compatibility From SilverlightCream.com: Modularity in Silverlight Applications - An Issue With ModuleInitializeException Max Paulousky has a truly ugly error trace listed by way of not having a reference listed, and the obvious simple solution. Next time he'll talk about the difficult situations. Using SketchFlow to Prototype for Windows Phone Christian Schormann has a tutorial up on using Expression Blend to develop for WP7 ... who better than Christian for that task?? Silverlight TV 18: WCF RIA Services Validation John Papa held forth with Nikhil Kothari on WCF RIA Services and validation just prior to MIX10, and was posted yesterday. Building SL3 applications using OData client Library with Vs 2010 RC Phani Raj walks through building an OData consumer in SL3, the first problem you're going to hit, and the easy solution to it. Tip: When creating a DependencyProperty, follow the handy convention of "wrapper+register+static+virtual" David Anson has a couple more of his 'Tips' up... this first is about Dependency Properties again... having a good foundation for all your Dependency Properties is a great way to avoid problems. Tip: Do not assign DependencyProperty values in a constructor; it prevents users from overriding them In the next post, David Anson talks about not assigning Dependency Property values in a constructor and gives one of the two ways to get around doing so. Tip: Set DependencyProperty default values in a class's default style if it's more convenient In his latest post, David Anson gives the second way to avoid setting a Dependency Property value in the constructor. Silverlight 4 + RIA Services - Ready for Business: Search Engine Optimization (SEO) Brad Abrams Abrams adds SEO to the tutorial series he's doing. He begins with his PDC09 session material on the subject and then takes off on a great detailed tutorial all with source. Silverlight 4 + RIA Services - Ready for Business: Localizing Business Application Brad Abrams then discusses localization and Silverlight in another detailed tutorial with all code included. Silverlight Toolkit and the Windows Phone: WrapPanel, and a few others Jeff Wilcox has a few WP7 posts I'm going to push today. This first is from earlier this week and is about using the Toolkit in WP7 and better than that, he includes the bits you need if all you want is the WrapPanel Data binding user settings in Windows Phone applications In the next one from yesterday, Jeff Wilcox demonstrates saving some user info in Isolated Storage to improve the user experience, and shares all the necessary plumbing files, and other external links as well. Displaying 2D QR barcodes in Windows Phone applications In a post from today, Jeff Wilcox ported his Silverlight 2D QR Barcode app from last year into WP7 ... just very cool... get the source and display your Microsoft Tag. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone    MIX10

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  • Master Note for Generic Data Warehousing

    - by lajos.varady(at)oracle.com
    ++++++++++++++++++++++++++++++++++++++++++++++++++++ The complete and the most recent version of this article can be viewed from My Oracle Support Knowledge Section. Master Note for Generic Data Warehousing [ID 1269175.1] ++++++++++++++++++++++++++++++++++++++++++++++++++++In this Document   Purpose   Master Note for Generic Data Warehousing      Components covered      Oracle Database Data Warehousing specific documents for recent versions      Technology Network Product Homes      Master Notes available in My Oracle Support      White Papers      Technical Presentations Platforms: 1-914CU; This document is being delivered to you via Oracle Support's Rapid Visibility (RaV) process and therefore has not been subject to an independent technical review. Applies to: Oracle Server - Enterprise Edition - Version: 9.2.0.1 to 11.2.0.2 - Release: 9.2 to 11.2Information in this document applies to any platform. Purpose Provide navigation path Master Note for Generic Data Warehousing Components covered Read Only Materialized ViewsQuery RewriteDatabase Object PartitioningParallel Execution and Parallel QueryDatabase CompressionTransportable TablespacesOracle Online Analytical Processing (OLAP)Oracle Data MiningOracle Database Data Warehousing specific documents for recent versions 11g Release 2 (11.2)11g Release 1 (11.1)10g Release 2 (10.2)10g Release 1 (10.1)9i Release 2 (9.2)9i Release 1 (9.0)Technology Network Product HomesOracle Partitioning Advanced CompressionOracle Data MiningOracle OLAPMaster Notes available in My Oracle SupportThese technical articles have been written by Oracle Support Engineers to provide proactive and top level information and knowledge about the components of thedatabase we handle under the "Database Datawarehousing".Note 1166564.1 Master Note: Transportable Tablespaces (TTS) -- Common Questions and IssuesNote 1087507.1 Master Note for MVIEW 'ORA-' error diagnosis. For Materialized View CREATE or REFRESHNote 1102801.1 Master Note: How to Get a 10046 trace for a Parallel QueryNote 1097154.1 Master Note Parallel Execution Wait Events Note 1107593.1 Master Note for the Oracle OLAP OptionNote 1087643.1 Master Note for Oracle Data MiningNote 1215173.1 Master Note for Query RewriteNote 1223705.1 Master Note for OLTP Compression Note 1269175.1 Master Note for Generic Data WarehousingWhite Papers Transportable Tablespaces white papers Database Upgrade Using Transportable Tablespaces:Oracle Database 11g Release 1 (February 2009) Platform Migration Using Transportable Database Oracle Database 11g and 10g Release 2 (August 2008) Database Upgrade using Transportable Tablespaces: Oracle Database 10g Release 2 (April 2007) Platform Migration using Transportable Tablespaces: Oracle Database 10g Release 2 (April 2007)Parallel Execution and Parallel Query white papers Best Practices for Workload Management of a Data Warehouse on the Sun Oracle Database Machine (June 2010) Effective resource utilization by In-Memory Parallel Execution in Oracle Real Application Clusters 11g Release 2 (Feb 2010) Parallel Execution Fundamentals in Oracle Database 11g Release 2 (November 2009) Parallel Execution with Oracle Database 10g Release 2 (June 2005)Oracle Data Mining white paper Oracle Data Mining 11g Release 2 (March 2010)Partitioning white papers Partitioning with Oracle Database 11g Release 2 (September 2009) Partitioning in Oracle Database 11g (June 2007)Materialized Views and Query Rewrite white papers Oracle Materialized Views  and Query Rewrite (May 2005) Improving Performance using Query Rewrite in Oracle Database 10g (December 2003)Database Compression white papers Advanced Compression with Oracle Database 11g Release 2 (September 2009) Table Compression in Oracle Database 10g Release 2 (May 2005)Oracle OLAP white papers On-line Analytic Processing with Oracle Database 11g Release 2 (September 2009) Using Oracle Business Intelligence Enterprise Edition with the OLAP Option to Oracle Database 11g (July 2008)Generic white papers Enabling Pervasive BI through a Practical Data Warehouse Reference Architecture (February 2010) Optimizing and Protecting Storage with Oracle Database 11g Release 2 (November 2009) Oracle Database 11g for Data Warehousing and Business Intelligence (August 2009) Best practices for a Data Warehouse on Oracle Database 11g (September 2008)Technical PresentationsA selection of ObE - Oracle by Examples documents: Generic Using Basic Database Functionality for Data Warehousing (10g) Partitioning Manipulating Partitions in Oracle Database (11g Release 1) Using High-Speed Data Loading and Rolling Window Operations with Partitioning (11g Release 1) Using Partitioned Outer Join to Fill Gaps in Sparse Data (10g) Materialized View and Query Rewrite Using Materialized Views and Query Rewrite Capabilities (10g) Using the SQLAccess Advisor to Recommend Materialized Views and Indexes (10g) Oracle OLAP Using Microsoft Excel With Oracle 11g Cubes (how to analyze data in Oracle OLAP Cubes using Excel's native capabilities) Using Oracle OLAP 11g With Oracle BI Enterprise Edition (Creating OBIEE Metadata for OLAP 11g Cubes and querying those in BI Answers) Building OLAP 11g Cubes Querying OLAP 11g Cubes Creating Interactive APEX Reports Over OLAP 11g CubesSelection of presentations from the BIWA website:Extreme Data Warehousing With Exadata  by Hermann Baer (July 2010) (slides 2.5MB, recording 54MB)Data Mining Made Easy! Introducing Oracle Data Miner 11g Release 2 New "Work flow" GUI   by Charlie Berger (May 2010) (slides 4.8MB, recording 85MB )Best Practices for Deploying a Data Warehouse on Oracle Database 11g  by Maria Colgan (December 2009)  (slides 3MB, recording 18MB, white paper 3MB )

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  • How to Create Views for All Tables with Oracle SQL Developer

    - by thatjeffsmith
    Got this question over the weekend via a friend and Oracle ACE Director, so I thought I would share the answer here. If you want to quickly generate DDL to create VIEWs for all the tables in your system, the easiest way to do that with SQL Developer is to create a data model. Wait, why would I want to do this? StackOverflow has a few things to say on this subject… So, start with importing a data dictionary. Step One: Open of Create a Model In SQL Developer, go to View – Data Modeler – Browser. Then in the browser panel, expand your design and create a new Relational Model. Step Two: Import your Data Dictionary This is a fancy way of saying, ‘suck objects out of the database into my model’ This will open a wizard to connect, select your schema(s), objects, etc. Once they’re in your model, you’re ready to cook with gas I’m using HR (Human Resources) for this example. You should end up with something that looks like this. Our favorite HR model Now we’re ready to generate the views! Step Three: Auto-generate the Views Go to Tools – Data Modeler – Table to View Wizard. I don’t want all my tables included, and I want to change the naming standard Decide if you want to change the default generated view names By default the views will be created as ‘V_TABLE_NAME.’ If you don’t like the ‘V_’ you can enter your own. You also can reference the object and model name with variables as shown in the screenshot above. I’m going to go with something a little more personal. The views are the little green boxes in the diagram Can’t find your views? They should be grouped together in your diagram. Don’t forget to use the Navigator to easily find and navigate to those model diagram objects! Step Four: Generate the DDL Ok, let’s use the Generate DDL button on the toolbar. Un-check everything but your views If you used a prefix, take advantage of that to create a filter. You might have existing views in your model that you don’t want to include, right? Once you click ‘OK’ the DDL will be generated. -- Generated by Oracle SQL Developer Data Modeler 4.0.0.825 -- at: 2013-11-04 10:26:39 EST -- site: Oracle Database 11g -- type: Oracle Database 11g CREATE OR REPLACE VIEW HR.TJS_BLOG_COUNTRIES ( COUNTRY_ID , COUNTRY_NAME , REGION_ID ) AS SELECT COUNTRY_ID , COUNTRY_NAME , REGION_ID FROM HR.COUNTRIES ; CREATE OR REPLACE VIEW HR.TJS_BLOG_EMPLOYEES ( EMPLOYEE_ID , FIRST_NAME , LAST_NAME , EMAIL , PHONE_NUMBER , HIRE_DATE , JOB_ID , SALARY , COMMISSION_PCT , MANAGER_ID , DEPARTMENT_ID ) AS SELECT EMPLOYEE_ID , FIRST_NAME , LAST_NAME , EMAIL , PHONE_NUMBER , HIRE_DATE , JOB_ID , SALARY , COMMISSION_PCT , MANAGER_ID , DEPARTMENT_ID FROM HR.EMPLOYEES ; CREATE OR REPLACE VIEW HR.TJS_BLOG_JOBS ( JOB_ID , JOB_TITLE , MIN_SALARY , MAX_SALARY ) AS SELECT JOB_ID , JOB_TITLE , MIN_SALARY , MAX_SALARY FROM HR.JOBS ; CREATE OR REPLACE VIEW HR.TJS_BLOG_JOB_HISTORY ( EMPLOYEE_ID , START_DATE , END_DATE , JOB_ID , DEPARTMENT_ID ) AS SELECT EMPLOYEE_ID , START_DATE , END_DATE , JOB_ID , DEPARTMENT_ID FROM HR.JOB_HISTORY ; CREATE OR REPLACE VIEW HR.TJS_BLOG_LOCATIONS ( LOCATION_ID , STREET_ADDRESS , POSTAL_CODE , CITY , STATE_PROVINCE , COUNTRY_ID ) AS SELECT LOCATION_ID , STREET_ADDRESS , POSTAL_CODE , CITY , STATE_PROVINCE , COUNTRY_ID FROM HR.LOCATIONS ; CREATE OR REPLACE VIEW HR.TJS_BLOG_REGIONS ( REGION_ID , REGION_NAME ) AS SELECT REGION_ID , REGION_NAME FROM HR.REGIONS ; -- Oracle SQL Developer Data Modeler Summary Report: -- -- CREATE TABLE 0 -- CREATE INDEX 0 -- ALTER TABLE 0 -- CREATE VIEW 6 -- CREATE PACKAGE 0 -- CREATE PACKAGE BODY 0 -- CREATE PROCEDURE 0 -- CREATE FUNCTION 0 -- CREATE TRIGGER 0 -- ALTER TRIGGER 0 -- CREATE COLLECTION TYPE 0 -- CREATE STRUCTURED TYPE 0 -- CREATE STRUCTURED TYPE BODY 0 -- CREATE CLUSTER 0 -- CREATE CONTEXT 0 -- CREATE DATABASE 0 -- CREATE DIMENSION 0 -- CREATE DIRECTORY 0 -- CREATE DISK GROUP 0 -- CREATE ROLE 0 -- CREATE ROLLBACK SEGMENT 0 -- CREATE SEQUENCE 0 -- CREATE MATERIALIZED VIEW 0 -- CREATE SYNONYM 0 -- CREATE TABLESPACE 0 -- CREATE USER 0 -- -- DROP TABLESPACE 0 -- DROP DATABASE 0 -- -- REDACTION POLICY 0 -- -- ERRORS 0 -- WARNINGS 0 You can then choose to save this to a file or not. This has a few steps, but as the number of tables in your system increases, so does the amount of time this feature can save you!

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  • IntelliTrace As a Learning Tool for MVC2 in a VS2010 Project

    - by Sam Abraham
    IntelliTrace is a new feature in Visual Studio 2010 Ultimate Edition. I see this valuable tool as a “Program Execution Recorder” that captures information about events and calls taking place as soon as we hit the VS2010 play (Start Debugging) button or the F5 key. Many online resources already discuss IntelliTrace and the benefit it brings to both developers and testers alike so I see no value of just repeating this information.  In this brief blog entry, I would like to share with you how I will be using IntelliTrace in my upcoming talk at the Ft Lauderdale ArcSig .Net User Group Meeting on April 20th 2010 (check http://www.fladotnet.com for more information), as a learning tool to demonstrate the internals of the lifecycle of an MVC2 application.  I will also be providing some helpful links that cover IntelliTrace in more detail at the end of my article for reference. IntelliTrace is setup by default to only capture execution events. Microsoft did such a great job on optimizing its recording process that I haven’t even felt the slightest performance hit with IntelliTrace running as I was debugging my solutions and projects.  For my purposes here however, I needed to capture more information beyond execution events, so I turned on the option for capturing calls in addition to events as shown in Figures 1 and 2. Changing capture options will require us to stop our debugging session and start over for the new settings to take place. Figure 1 – Access IntelliTrace options via the Tools->Options menu items Figure 2 – Change IntelliTrace Options to capture call information as well as events Notice the warning with regards to potentially degrading performance when selecting to capture call information in addition to the default events-only setting. I have found this warning to be sure true. My subsequent tests showed slowness in page load times compared to rendering those same exact pages with the “event-only” option selected. Execution recording is auto-started along with the new debugging session of our project. At this point, we can simply interact with the application and continue executing normally until we decide to “playback” the code we have executed so far.  For code replay, first step is to “break” the current execution as show in Figure 3.   Figure 3 – Break to replay recording A few tries later, I found a good process to quickly find and demonstrate the MVC2 page lifecycle. First-off, we start with the event view as shown in Figure 4 until we find an interesting event that needs further studying.  Figure 4 – Going through IntelliTrace’s events and picking as specific entry of interest We now can, for instance, study how the highlighted HTTP GET request is being handled, by clicking on the “Calls View” for that particular event. Notice that IntelliTrace shows us all calls that took place in servicing that GET request. Double clicking on any call takes us to a more granular view of the call stack within that clicked call, up until getting to a specific line of code where we can do a line-by-line replay of the execution from that point onwards using F10 or F11 just like our typical good old VS2008 debugging helped us accomplish. Figure 5 – switching to call view on an event of interest Figure 6 – Double clicking on call shows a more granular view of the call stack. In conclusion, the introduction of IntelliTrace as a new addition to the VS developers’ tool arsenal enhances development and debugging experience and effectively tackles the “no-repro” problem. It will also hopefully enhance my audience’s experience listening to me speaking about  an MVC2 page lifecycle which I can now easily visually demonstrate, thereby improving the probability of keeping everybody awake a little longer. IntelliTrace References: http://msdn.microsoft.com/en-us/magazine/ee336126.aspx http://msdn.microsoft.com/en-us/library/dd264944(VS.100).aspx

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  • SQL SERVER – Guest Post – Jacob Sebastian – Filestream – Wait Types – Wait Queues – Day 22 of 28

    - by pinaldave
    Jacob Sebastian is a SQL Server MVP, Author, Speaker and Trainer. Jacob is one of the top rated expert community. Jacob wrote the book The Art of XSD – SQL Server XML Schema Collections and wrote the XML Chapter in SQL Server 2008 Bible. See his Blog | Profile. He is currently researching on the subject of Filestream and have submitted this interesting article on the very subject. What is FILESTREAM? FILESTREAM is a new feature introduced in SQL Server 2008 which provides an efficient storage and management option for BLOB data. Many applications that deal with BLOB data today stores them in the file system and stores the path to the file in the relational tables. Storing BLOB data in the file system is more efficient that storing them in the database. However, this brings up a few disadvantages as well. When the BLOB data is stored in the file system, it is hard to ensure transactional consistency between the file system data and relational data. Some applications store the BLOB data within the database to overcome the limitations mentioned earlier. This approach ensures transactional consistency between the relational data and BLOB data, but is very bad in terms of performance. FILESTREAM combines the benefits of both approaches mentioned above without the disadvantages we examined. FILESTREAM stores the BLOB data in the file system (thus takes advantage of the IO Streaming capabilities of NTFS) and ensures transactional consistency between the BLOB data in the file system and the relational data in the database. For more information on the FILESTREAM feature, visit: http://beyondrelational.com/filestream/default.aspx FILESTREAM Wait Types Since this series is on the different SQL Server wait types, let us take a look at the various wait types that are related to the FILESTREAM feature. FS_FC_RWLOCK This wait type is generated by FILESTREAM Garbage Collector. This occurs when Garbage collection is disabled prior to a backup/restore operation or when a garbage collection cycle is being executed. FS_GARBAGE_COLLECTOR_SHUTDOWN This wait type occurs when during the cleanup process of a garbage collection cycle. It indicates that that garbage collector is waiting for the cleanup tasks to be completed. FS_HEADER_RWLOCK This wait type indicates that the process is waiting for obtaining access to the FILESTREAM header file for read or write operation. The FILESTREAM header is a disk file located in the FILESTREAM data container and is named “filestream.hdr”. FS_LOGTRUNC_RWLOCK This wait type indicates that the process is trying to perform a FILESTREAM log truncation related operation. It can be either a log truncate operation or to disable log truncation prior to a backup or restore operation. FSA_FORCE_OWN_XACT This wait type occurs when a FILESTREAM file I/O operation needs to bind to the associated transaction, but the transaction is currently owned by another session. FSAGENT This wait type occurs when a FILESTREAM file I/O operation is waiting for a FILESTREAM agent resource that is being used by another file I/O operation. FSTR_CONFIG_MUTEX This wait type occurs when there is a wait for another FILESTREAM feature reconfiguration to be completed. FSTR_CONFIG_RWLOCK This wait type occurs when there is a wait to serialize access to the FILESTREAM configuration parameters. Waits and Performance System waits has got a direct relationship with the overall performance. In most cases, when waits increase the performance degrades. SQL Server documentation does not say much about how we can reduce these waits. However, following the FILESTREAM best practices will help you to improve the overall performance and reduce the wait types to a good extend. Read all the post in the Wait Types and Queue series. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, Readers Contribution, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQL Wait Stats, SQL Wait Types, T SQL, Technology Tagged: Filestream

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  • SQLAuthority News – The Best Quotes of “Who Wrote This?” Contest

    - by pinaldave
    I am a frequent reader of Brent Ozar PLF, it is one of my favorite blogs. A recent post announced a “Who Wrote This?” contest to see if readers could tell their three contributors apart based on some writing samples. Here are my favorite lines from the sample paragraphs, from each of the three “mystery authors.” Topic 1: Working with Bad Managers Mystery Author A – “Working with bad managers means working against my own happiness, and I’ve come to learn that there’s no changing bad managers.” I love this line because, as anyone who has had a bad manager knows, often a lot of self-doubt rises up. We all have to remember that sometimes the problem is out of our control. Mystery Author B – “Mentor your manager just like you would mentor a junior DBA.” Having a bad manager can be extremely depressing, and we often feel out of control. But we all need to remember that our work is a two-way street, and that sometimes we can subtly influence those above us. Mystery Author C – “The trick to working for all bad managers is to remember that they aren’t your parent. Take charge of your career.” We all also need to learn not to play the blame game. Would you rather stay in a place where you are unhappy, or would you rather take charge of your life? I hope most people would pick the latter. Topic 2: Working with Remote Teams Mystery Author A – “Like almost anything else the key is to make sure that everyone on the team has an understanding of how and when communication will occur.” Communication is so important. I cannot over emphasize how much. And this one line captures how I feel and even communicates the idea clearly! Mystery Author B – “The key to remote team success is verifiable trust: feeling confident that invisible team members are doing the right amount of the right thing at the right time.” I think this line not only captures the key aspects of remote work – verifiable work and trust – but there were so many lines that followed that I loved and could not fit here. The whole paragraph is a list for successful remote work. Everyone could benefit from reading it. Mystery Author C – “What seems clear, precise, and specific in one time zone comes across as vague, soupy, and just plain weird in another.” You know what? I just love this description. The author is right – sometimes vague e-mails really do seem soupy and weird! Topic 3: Working with Your Nemesis Mystery Author A – “Every job is temporary, but your reputation stays with you.” Everyone needs to remember this. The workplace is meant to be a professional arena, and many people have the opinion that work is temporary and disposable. No one wants to work with co-worker like that. Mystery Author B – “Unhealthy conflict is going to lead to leaving three week old tuna fish sandwiches in someone’s desk drawer.” Sometimes humor really is the best policy! Mystery Author C – “Oh no, it’s that guy.” This might seem like a weird phrase to choose as my favorite from an entire paragraph. But the whole piece was written in the form of a story of co-workers getting drunk and plotting against a nemesis. It was too funny to overlook, but too long to post here. A must read! Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority News, T SQL, Technology

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  • SQL SERVER – A Picture is Worth a Thousand Words – A Collection of Inspiring and Funny Posts by Vinod Kumar

    - by pinaldave
    One of the most popular quotes is: A picture is worth a thousand words. Working on this concept I started a series over my blog called the “Picture Post”. Rather than rambling over tons of material over text, we are trying to give you a capsule mode of the blog in a quick glance. Some of the picture posts already available over my blog are: Correlation of Ego and Work: Ego and Pride most of the times become a hindrance when we work inside a team. Take this cue, the first ever Picture post was published. Simple and easy to understand concept. Would want to say, Ego is the biggest enemy to humans. Read Original Post. Success (Perception Vs Reality): Personally, have always thought success is not something the talented achieve with the opportunity presented to them, but success is developed using the opportunity in hand now. In this fast paced world where success is pre-defined and convoluted by metrics it is hard to understand how complex it can sometimes be. So I took a stab at this concept in a simple way. Read Original Post. Doing Vs Saying: As Einstein would describe, Insanity is doing the same thing over and over again and expecting different results. Given the amount of information we get, it is difficult to keep track, learn and implement the same. If you were ever reminded of your college days, there will always be 5-6 people doing different things and we naturally try to emulate what they are doing. This could be from competitive exams GMAT, GRE, CAT, Higher-Ed, B-School hunting etc. Rather than saying you are going to do, it is best to do and then say!!! Read Original Picture Post. Your View Vs Management View: Being in the corporate world can be really demanding and we keep asking this question – “Why me?” when the performance appraisal process ends. In this post I just want to ask you one frank opinion – “Are you really self-critical in your assessments?”. If that is the case there shouldn’t be any heartburns or surprises. If you had just one thing to take back, well forget what others are getting but invest time in making yourself better because that is going to take you longer and further in your career. Read Picture Post. Blogging lifecycle for majority: I am happy and fortunate to be in this blog post because this picture post surely doesn’t apply to SQLAuthority where consistency and persistence have been the hallmark of the blog. For the majority others, who have a tendency to start a blog, get into slumber for a while and write saying they want to get back to blogging, the picture post was specifically done for them. Paradox of being someone else: It is always a dream that we want to become somebody and in this process of doing so, we become nobody. In this constant tussle of lost identity we forget to enjoy the moment that is in front of us. I just depicted this using a simple analogy of our constant struggle to get to the other side, just to realize we missed the wonderful moments. Grass is not greener on the other side, but grass is greener where we water the surface. Read Picture Post. And on the lighter side… Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: About Me, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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