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  • The Database as Intellectual Property

    - by Jonathan Kehayias
    Every so often, a question shows up on the forums in the form of, “How do I prevent anyone from accessing my database schema, including local administrators and sysadmins in SQL Server?”  I usually laugh a little shake my head when I read a question like this because it demonstrates an complete lack of understanding of the power an administrator has over SQL Server.  The simple answer is this: If you don’t want your database schema to ever be accessed or known, don’t distribute your database....(read more)

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  • BI Beginner: Excel 2013 Power View Maps

    - by John Paul Cook
    If you know how to use Excel, you can be productive in minutes with the new features of Excel 2013. Don’t be intimidated. Follow these simple steps and produce something snazzy! The Excel file used in this example comes from the following SQL Server query which was run against the AdventureWorks2012 database: SELECT Purchasing . Vendor . Name , Person . Address . City , Person . StateProvince . Name AS State FROM Purchasing . Vendor INNER JOIN Person . BusinessEntityAddress ON Purchasing . Vendor...(read more)

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  • October 2013 Cumulative Update for SQL Server 2008 R2

    - by AaronBertrand
    Microsoft has released Cumulative Update #9 for SQL Server 2008 R2 Service Pack 2. KB Article: KB #2887606 17 fixes listed at time of publication Build number is 10.50.4295 Relevant for @@VERSION 10.50.4000 through 10.50.4294 My usual disclaimer: these updates are NOT for SQL Server 2008 (or SQL Server 2012). Only apply to systems where SELECT @@VERSION returns 10.50.xxxx, where xxxx is >= 2500. If xxxx < 2500, you need to start thinking about getting off the RTM branch. Note that no more cumulative...(read more)

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  • Learning PostgreSql: old versions of rows are stored right in the table

    - by Alexander Kuznetsov
    PostgreSql features multi-version concurrency control aka MVCC. To implement MVCC, old versions of rows are stored right in the same table, and this is very different from what SQL Server does, and it leads to some very interesting consequences. Let us play with this thing a little bit, but first we need to set up some test data. Setting up. First of all, let us create a numbers table. Any production database must have it anyway: CREATE TABLE Numbers ( i INTEGER ); INSERT INTO Numbers ( i ) VALUES...(read more)

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  • The importance of Unit Testing in BI

    - by Davide Mauri
    One of the main steps in the process we internally use to develop a BI solution is the implementation of Unit Test of you BI Data. As you may already know, I’ve create a simple (for now) tool that leverages NUnit to allow us to quickly create Unit Testing without having to resort to use Visual Studio Database Professional: http://queryunit.codeplex.com/ Once you have a tool like this one, you can start also to make sure that your BI solution (DWH and CUBE) is not only structurally sound (I mean, the cube or the report gets processed correctly), but you can also check that the logical integrity of your business rules is enforced. For example let’s say that the customer tell you that they will never create an invoice for a specific product-line in 2010 since that product-line is dismissed and will never be sold again. Ok we know that this in theory is true, but a lot of this business rule effectiveness depends on the fact the people does not do a mistake while inserting new orders/invoices and the ERP used implements a check for this business logic. Unfortunately these last two hypotesis are not always true, so you may find yourself really having some invoices for a product line that doesn’t exists anymore. Maybe this kind of situation in future will be solved using Master Data Management but, meanwhile, how you can give and idea of the data quality to your customers? How can you check that logical integrity of the analytical data you produce is exactly what you expect? Well, Unit Testing of a DWH or a CUBE can be a solution. Once you have defined your test suite, by writing SQL and MDX queries that checks that your data is what you expect to be, if you use NUnit (and QueryUnit does), you can then use a tool like NUnit2Report to create a nice HTML report that can be shipped via email to give information of data quality: In addition to that, since NUnit produces an XML file as a result, you can also import it into a SQL Server Database and then monitor the quality of data over time. I’ll be speaking about this approach (and more in general about how to “engineer” a BI solution) at the next European SQL PASS Adaptive BI Best Practices http://www.sqlpass.org/summit/eu2010/Agenda/ProgramSessions/AdaptiveBIBestPratices.aspx I’ll enjoy discussing with you all about this, so see you there! And remember: “if ain't tested it's broken!” (Sorry I don’t remember how said that in first place :-)) Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • In defense of SELECT * in production code, in some limited cases?

    - by Alexander Kuznetsov
    It is well known that SELECT * is not acceptable in production code, with the exception of this pattern: IF EXISTS( SELECT * We all know that whenever we see code code like this: Listing 1. "Bad" SQL SELECT Column1 , Column2 FROM ( SELECT c. * , ROW_NUMBER () OVER ( PARTITION BY Column1 ORDER BY Column2 ) AS rn FROM data.SomeTable AS c ) AS c WHERE rn < 5 we are supposed to automatically replace * with an explicit list of columns, as follows: Listing 2. "Good" SQL SELECT Column1 , Column2 FROM...(read more)

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  • Six Unusual Blogs I Like

    - by Bill Graziano
    I subscribe to and read over 100 SQL Server blogs every day.  I link to posts that I think are interesting.  I also read a fair number of non-SQL Server blogs.  Here are a few that I think are interesting. danah boyd. She is a researcher with Microsoft and writes about privacy, social media and teenagers.  I discovered her blog while looking for strategies to keep my personal and professional life separate.  (I haven’t found a good solution to that yet.)  Her stories of how teenagers use Facebook and other social media tools are fascinating. Clayton’s Web Snacks.  Steve Clayton works at Microsoft and has a variety of blogs out there.  This one focuses on … hmmm.  His latest posts are on graffiti, infographics, paper tweets, cartoons and slow motion videos.  It’s mostly visual and you never really know what you’ll get.  It’s always interesting though and I like what he posts.  It’s good creative stuff. Seth Godin.  Seth writes about Marketing.  I read him for motivation to get off my butt and get things done.  He’s a great motivator who encourages you to think big.  And do something! Ask the Pilot.  Patrick Smith is a commercial airline pilot writing about the airline industry.  He’s a great debunker of myths (no they don’t reduce oxygen in the cabin to keep you docile).  My favorite topics include the TSA, flying myths, airport reviews and flight delays. My old favorite flight blog used to be enplaned.  No one knew who wrote it.  It focused on the economics of the airline industry.  It was fascinating stuff.  One day it was gone.  The entire blog was deleted.  Someone tracked down some partial archives and put them online. The Agent’s Journal.  Jack Bechta is an NFL agent.  He writes about the business side of the NFL, the draft and free agency.  Lately he’s been writing about the potential lockout.  He has a distinct lack of hype which I find very refreshing.  xkcd.  I call this the comic for smart people.  A little math, some IT and internet privacy thrown in all make an unusual comic. Funny and intelligent.

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  • Cumulative Update #7 for SQL Server 2008 Service Pack 3 is available

    - by AaronBertrand
    Today Microsoft has released a new cumulative update for SQL Server 2008. Cumulative Update #7 for SQL Server 2008 Service Pack 3 Knowledge Base Article: KB #2738350 At the time of writing, there are 9 fixes listed The build number is 10.00.5794 Relevant for @@VERSION between 10.00.5500 and 10.00.5793 No word yet on an update for Service Pack 2. As usual, I'll post my standard disclaimer here: these updates are NOT for SQL Server 2008 R2 (where @@VERSION will report 10.50.xxxx)....(read more)

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  • Quote of the Day: On Being Enthusiastic

    - by BuckWoody
    I had a great time with some fellow “tweeters” on the Microsoft campus yesterday. We were pretty fired up – and there’s nothing wrong with that!  In fact:   “If you aren't fired with enthusiasm, you will be fired, with enthusiasm.” - Vince Lombardi Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • SQL Saturday #39 in NYC

    - by roman
    This weekend I will be speaking at the NYC SQL Saturday . The whole event was supposed to be BI focused but now the schedule shows a lot of non BI stuff as well. I will be presenting SQL Server 2008 Reporting Services Programming , one of my favorite topics to present on. It seems that the event if fully booked. I'll be coming down on my bike taking scenic roads through MA and CT so I will not make it to the speaker dinner. But the forecast looks good so I am pretty psyched to finally venture out...(read more)

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  • Highlight Word add-in for Visual Studio 2010 [SSDT]

    - by jamiet
    I’ve just been alerted by my colleague Kyle Harvie to a Visual Studio 2010 add-in that should prove very useful if you are an SSDT user. Its simply called Highlight all occurrences of selected word and does exactly what it says on the tin, you highlight a word and it shows all other occurrences of that word in your script: There’s a limitation for .sql files (which I have reported) where the highlighting doesn’t work if the word is wrapped in square brackets but what the heck, its free, it takes about ten seconds to install….install it already! @Jamiet

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  • T-SQL Tuesday: Personality Clashes, Style Collisions, and Differences of Opinion

    - by andyleonard
    This post is the twenty-sixth part of a ramble-rant about the software business. The current posts in this series are: Goodwill, Negative and Positive Visions, Quests, Missions Right, Wrong, and Style Follow Me Balance, Part 1 Balance, Part 2 Definition of a Great Team The 15-Minute Meeting Metaproblems: Drama The Right Question Software is Organic, Part 1 Metaproblem: Terror I Don't Work On My Car A Turning Point Human Doings Everything Changes Getting It Right The First Time One-Time Boosts Institutionalized!...(read more)

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  • Take Advantage of Oracle's Ongoing Assurance Effort!

    - by eric.maurice
    Hi, this is Eric Maurice again! A few years ago, I posted a blog entry, which discussed the psychology of patching. The point of this blog entry was that a natural tendency existed for systems and database administrators to be reluctant to apply patches, even security patches, because of the fear of "breaking" the system. Unfortunately, this belief in the principle "if it ain't broke, don't fix it!" creates significant risks for organizations. Running systems without applying the proper security patches can greatly compromise the security posture of the organization because the security controls available in the affected system may be compromised as a result of the existence of the unfixed vulnerabilities. As a result, Oracle continues to strongly recommend that customers apply all security fixes as soon as possible. Most recently, I have had a number of conversations with customers who questioned the need to upgrade their highly stable but otherwise unsupported Oracle systems. These customers wanted to know more about the kind of security risks they were exposed to, by running obsolete versions of Oracle software. As per Oracle Support Policies, Critical Patch Updates are produced for currently supported products. In other words, Critical Patch Updates are not created by Oracle for product versions that are no longer covered under the Premier Support or Extended Support phases of the Lifetime Support Policy. One statement used in each Critical Patch Update Advisory is particularly important: "We recommend that customers upgrade to a supported version of Oracle products in order to obtain patches. Unsupported products, releases and versions are not tested for the presence of vulnerabilities addressed by this Critical Patch Update. However, it is likely that earlier versions of affected releases are also affected by these vulnerabilities." The purpose of this warning is to inform Oracle customers that a number of the vulnerabilities fixed in each Critical Patch Update may affect older versions of a specific product line. In other words, each Critical Patch Update provides a number of fixes for currently supported versions of a given product line (this information is listed for each bug in the Risk Matrices of the Critical Patch Update Advisory), but the unsupported versions in the same product line, while they may be affected by the vulnerabilities, will not receive the fixes, and are therefore vulnerable to attacks. The risk assumed by organizations wishing to remain on unsupported versions is amplified by the behavior of malicious hackers, who typically will attempt to, and sometimes succeed in, reverse-engineering the content of vendors' security fixes. As a result, it is not uncommon for exploits to be published soon after Oracle discloses vulnerabilities with the release of a Critical Patch Update or Security Alert. Let's consider now the nature of the vulnerabilities that may exist in obsolete versions of Oracle software. A number of severe vulnerabilities have been fixed by Oracle over the years. While Oracle does not test unsupported products, releases and versions for the presence of vulnerabilities addressed by each Critical Patch Update, it should be assumed that a number of the vulnerabilities fixed with the Critical Patch Update program do exist in unsupported versions (regardless of the product considered). The most severe vulnerabilities fixed in past Critical Patch Updates may result in full compromise of the targeted systems, down to the OS level, by remote and unauthenticated users (these vulnerabilities receive a CVSS Base Score of 10.0) or almost as critically, may result in the compromise of the affected systems (without compromising the underlying OS) by a remote and unauthenticated users (these vulnerabilities receive a CVSS Base Score of 7.5). Such vulnerabilities may result in complete takeover of the targeted machine (for the CVSS 10.0), or may result in allowing the attacker the ability to create a denial of service against the affected system or even hijacking or stealing all the data hosted by the compromised system (for the CVSS 7.5). The bottom line is that organizations should assume the worst case: that the most critical vulnerabilities are present in their unsupported version; therefore, it is Oracle's recommendation that all organizations move to supported systems and apply security patches in a timely fashion. Organizations that currently run supported versions but may be late in their security patch release level can quickly catch up because most Critical Patch Updates are cumulative. With a few exceptions noted in Oracle's Critical Patch Update Advisory, the application of the most recent Critical Patch Update will bring these products to current security patch level and provide the organization with the best possible security posture for their patch level. Furthermore, organizations are encouraged to upgrade to most recent versions as this will greatly improve their security posture. At Oracle, our security fixing policies state that security fixes are produced for the main code line first, and as a result, our products benefit from the mistakes made in previous version(s). Our ongoing assurance effort ensures that we work diligently to fix the vulnerabilities we find, and aim at constantly improving the security posture our products provide by default. Patch sets include numerous in-depth fixes in addition to those delivered through the Critical Patch Update and, in certain instances, important security fixes require major architectural changes that can only be included in new product releases (and cannot be backported through the Critical Patch Update program). For More Information: • Mary Ann Davidson is giving a webcast interview on Oracle Software Security Assurance on February 24th. The registration link for attending this webcast is located at http://event.on24.com/r.htm?e=280304&s=1&k=6A7152F62313CA09F77EBCEEA9B6294F&partnerref=EricMblog • A blog entry discussing Oracle's practices for ensuring the quality of Critical patch Updates can be found at http://blogs.oracle.com/security/2009/07/ensuring_critical_patch_update_quality.html • The blog entry "To patch or not to patch" is located at http://blogs.oracle.com/security/2008/01/to_patch_or_not_to_patch.html • Oracle's Support Policies are located at http://www.oracle.com/us/support/policies/index.html • The Critical Patch Update & Security Alert page is located at http://www.oracle.com/technetwork/topics/security/alerts-086861.html

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  • Adaptive Case Management OTN WebCast with Danilo Schmiedel

    - by JuergenKress
    Oracle ACE Director Danilo Schmiedel, SOA/BPM solution architect with Opitz Consulting in Germany, talks about Adaptive Case Management, Predictive Analytics, and Process Mining. Watch the video here. To download the Adaptive Case Management post mentioned in this interview, please visit the blog post. SOA & BPM Partner Community For regular information on Oracle SOA Suite become a member in the SOA & BPM Partner Community for registration please visit www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Facebook Wiki Technorati Tags: ACM,Adaptive Case Management,Danilo Schmiedel,Opitz,OTN,SOA Community,Oracle SOA,Oracle BPM,Community,OPN,Jürgen Kress

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  • Links to C++ documentation

    - by Daniel Moth
    After a recent talk I gave on C++ AMP, one attendee was complaining that they were not familiar with lambdas and another found templates hard to parse. In case you are in the same boat, I thought I'd gather some essential reading material for you (also gives me one link to use in the future for referring people to ;-) Lambdas are available (in some shape or form) in all modern languages, so do yourself a favor and learn about them: Lambda Expressions in C++ (and also syntax and examples) Watch Herb Sutter's full length session on lambdas at PDC 2010 Templates, have been around in modern languages for even longer than lambdas (e.g. Generics in .NET), so again go dive in: Templates topic with full table of contents linking to subtopics In fact, why don't you refresh your knowledge and read the entire msdn C++ Language Reference – that's what I am doing! If you are looking to keep up to date with what is happening in the C++ world, stay tuned on the Visual C++ team (aka WinC++ team) blog and ask questions in the C++ forums. Comments about this post welcome at the original blog.

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  • SQL Server v.Next ("Denali") : How a columnstore index is not like a normal index

    - by AaronBertrand
    At the end of my Denali presentation at SQL Saturday #65 in Vancouver, a member of the audience asked, "What makes a columnstore index different from a regular nonclustered index?" At the end of a busy day, I was at a loss for an answer, and I'll explain why. First, I'll briefly explain the basic, core, high-level functionality of a columnstore index (you can read a lot more details in this white paper ). Basically, instead of storing index data together on a page, it divvies up the data from each...(read more)

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  • In the Cloud, Everything Costs Money

    - by BuckWoody
    I’ve been teaching my daughter about budgeting. I’ve explained that most of the time the money coming in is from only one or two sources – and you can only change that from time to time. The money going out, however, is to many locations, and it changes all the time. She’s made a simple debits and credits spreadsheet, and I’m having her research each part of the budget. Her eyes grow wide when she finds out everything has a cost – the house, gas for the lawnmower, dishes, water for showers, food, electricity to run the fridge, a new fridge when that one breaks, everything has a cost. She asked me “how do you pay for all this?” It’s a sentiment many adults have looking at their own budgets – and one reason that some folks don’t even make a budget. It’s hard to face up to the realities of how much it costs to do what we want to do. When we design a computing solution, it’s interesting to set up a similar budget, because we don’t always consider all of the costs associated with it. I’ve seen design sessions where the new software or servers are considered, but the “sunk” costs of personnel, networking, maintenance, increased storage, new sizes for backups and offsite storage and so on are not added in. They are already on premises, so they are assumed to be paid for already. When you move to a distributed architecture, you'll see more costs directly reflected. Store something, pay for that storage. If the system is deployed and no one is using it, you’re still paying for it. As you watch those costs rise, you might be tempted to think that a distributed architecture costs more than an on-premises one. And you might be right – for some solutions. I’ve worked with a few clients where moving to a distributed architecture doesn’t make financial sense – so we didn’t implement it. I still designed the system in a distributed fashion, however, so that when it does make sense there isn’t much re-architecting to do. In other cases, however, if you consider all of the on-premises costs and compare those accurately to operating a system in the cloud, the distributed system is much cheaper. Again, I never recommend that you take a “here-or-there-only” mentality – I think a hybrid distributed system is usually best – but each solution is different. There simply is no “one size fits all” to architecting a solution. As you design your solution, cost out each element. You might find that using a hybrid approach saves you money in one design and not in another. It’s a brave new world indeed. So yes, in the cloud, everything costs money. But an on-premises solution also costs money – it’s just that “dad” (the company) is paying for it and we don’t always see it. When we go out on our own in the cloud, we need to ensure that we consider all of the costs.

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  • Smart defaults [SSDT]

    - by jamiet
    I’ve just discovered a new, somewhat hidden, feature in SSDT that I didn’t know about and figured it would be worth highlighting here because I’ll bet not many others know it either; the feature is called Smart Defaults. It gets around the problem of adding a NOT NULLable column to an existing table that has got data in it – previous to SSDT you would need to define a DEFAULT constraint however it does feel rather cumbersome to create an object purely for the purpose of pushing through a deployment – that’s the situation that Smart Defaults is meant to alleviate. The Smart Defaults option exists in the advanced section of a Publish Profile file: The description of the setting is “Automatically provides a default value when updating a table that contains data with a column that does not allow null values”, in other words checking that option will cause SSDT to insert an arbitrary default value into your newly created NON NULLable column. In case you’re wondering how it does it, here’s how: SSDT creates a DEFAULT CONSTRAINT at the same time as the column is created and then immediately removes that constraint: ALTER TABLE [dbo].[T1]    ADD [C1] INT NOT NULL,         CONSTRAINT [SD_T1_1df7a5f76cf44bb593506d05ff9a1e2b] DEFAULT 0 FOR [C1];ALTER TABLE [dbo].[T1] DROP CONSTRAINT [SD_T1_1df7a5f76cf44bb593506d05ff9a1e2b]; You can then update the value as appropriate in a Post-Deployment script. Pretty cool! On the downside, you can only specify this option for the whole project, not for an individual table or even an individual column – I’m not sure that I’d want to turn this on for an entire project as it could hide problems that a failed deployment would highlight, in other words smart defaults could be seen to be “papering over the cracks”. If you think that should be improved go and vote (and leave a comment) at [SSDT] Allow us to specify Smart defaults per table or even per column. @Jamiet

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  • Is SQL Server 2008 R2 a full release of SQL Server?

    - by AaronBertrand
    This has come up in conversations more than once in the past little while - recently on twitter I made the casual comment that later this year, SQL Server 2008 will be "two versions old." Well, not everyone agrees that that is technically true. So, I thought I'd put something out there that isn't limited to 140 characters. There are certainly some valid arguments on both sides, but my opinion - based both on these facts and on my memory that Microsoft has marketed it as such - is that SQL Server...(read more)

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  • SQL SERVER – Finding Latch Statistics

    - by pinaldave
    Last month I wrote SQL Server Wait Types and Queues series SQL SERVER – Summary of Month – Wait Type – Day 28 of 28. I had great fun to write the series. I learned a lot and I felt this has created some deep interest on the subject with others. I recently received very interesting question from one of the reader after reading SQL SERVER – PAGELATCH_DT, PAGELATCH_EX, PAGELATCH_KP, PAGELATCH_SH, PAGELATCH_UP – Wait Type – Day 12 of 28 that if they can know what kind of latches are waiting and what is their count. Absolutely! SQL Server team has already provided DMV which does the same. -- Latch SELECT * FROM sys.dm_os_latch_stats ORDER BY wait_time_ms DESC Above script will return you details about how many latches were waiting for how long. After going over this script I feel like going deep into the subject further. I will post a blog post on the subject soon. 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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  • BPM Workspace and Webforms customization by Bruno Neves Alves

    - by JuergenKress
    Under the propose of a project customization customization on BPM workspace and designed webforms were applied using custom css and used as skin and as webforms theme. Its important also to highlight that a workspace skin appliance is enough to bring customization to your webforms since they will inherit the workspace skin customization, nevertheless, themes offers you the possibility to enrich that customization or even to overlap it if desired. This blog post shares my experience trying what is available today as sample from Oracle Samples site but also how I found it starting from scratch. I have follow the following contents to achieve a full workspace and webforms customization: Read the complete article here. SOA & BPM Partner Community For regular information on Oracle SOA Suite become a member in the SOA & BPM Partner Community for registration please visit www.oracle.com/goto/emea/soa (OPN account required) If you need support with your account please contact the Oracle Partner Business Center. Blog Twitter LinkedIn Facebook Wiki Technorati Tags: Bruno Neves Alves,BPM Workspace,Webforms,SOA Community,Oracle SOA,Oracle BPM,Community,OPN,Jürgen Kress

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  • SQL University: Parallelism Week - Introduction

    - by Adam Machanic
    Welcome to Parallelism Week at SQL University . My name is Adam Machanic, and I'm your professor. Imagine having 8 brains, or 16, or 32. Imagine being able to break up complex thoughts and distribute them across your many brains, so that you could solve problems faster. Now quit imagining that, because you're human and you're stuck with only one brain, and you only get access to the entire thing if you're lucky enough to have avoided abusing too many recreational drugs. For your database server,...(read more)

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  • PASS Summit 2011 &ndash; Part III

    - by Tara Kizer
    Well we’re about a month past PASS Summit 2011, and yet I haven’t finished blogging my notes! Between work and home life, I haven’t been able to come up for air in a bit.  Now on to my notes… On Thursday of the PASS Summit 2011, I attended Klaus Aschenbrenner’s (blog|twitter) “Advanced SQL Server 2008 Troubleshooting”, Joe Webb’s (blog|twitter) “SQL Server Locking & Blocking Made Simple”, Kalen Delaney’s (blog|twitter) “What Happened? Exploring the Plan Cache”, and Paul Randal’s (blog|twitter) “More DBA Mythbusters”.  I think my head grew two times in size from the Thursday sessions.  Just WOW! I took a ton of notes in Klaus' session.  He took a deep dive into how to troubleshoot performance problems.  Here is how he goes about solving a performance problem: Start by checking the wait stats DMV System health Memory issues I/O issues I normally start with blocking and then hit the wait stats.  Here’s the wait stat query (Paul Randal’s) that I use when working on a performance problem.  He highlighted a few waits to be aware of such as WRITELOG (indicates IO subsystem problem), SOS_SCHEDULER_YIELD (indicates CPU problem), and PAGEIOLATCH_XX (indicates an IO subsystem problem or a buffer pool problem).  Regarding memory issues, Klaus recommended that as a bare minimum, one should set the “max server memory (MB)” in sp_configure to 2GB or 10% reserved for the OS (whichever comes first).  This is just a starting point though! Regarding I/O issues, Klaus talked about disk partition alignment, which can improve SQL I/O performance by up to 100%.  You should use 64kb for NTFS cluster, and it’s automatic in Windows 2008 R2. Joe’s locking and blocking presentation was a good session to really clear up the fog in my mind about locking.  One takeaway that I had no idea could be done was that you can set a timeout in T-SQL code view LOCK_TIMEOUT.  If you do this via the application, you should trap error 1222. Kalen’s session went into execution plans.  The minimum size of a plan is 24k.  This adds up fast especially if you have a lot of plans that don’t get reused much.  You can use sys.dm_exec_cached_plans to check how often a plan is being reused by checking the usecounts column.  She said that we can use DBCC FLUSHPROCINDB to clear out the stored procedure cache for a specific database.  I didn’t know we had this available, so this was great to hear.  This will be less intrusive when an emergency comes up where I’ve needed to run DBCC FREEPROCCACHE. Kalen said one should enable “optimize for ad hoc workloads” if you have an adhoc loc.  This stores only a 300-byte stub of the first plan, and if it gets run again, it’ll store the whole thing.  This helps with plan cache bloat.  I have a lot of systems that use prepared statements, and Kalen says we simulate those calls by using sp_executesql.  Cool! Paul did a series of posts last year to debunk various myths and misconceptions around SQL Server.  He continues to debunk things via “DBA Mythbusters”.  You can get a PDF of a bunch of these here.  One of the myths he went over is the number of tempdb data files that you should have.  Back in 2000, the recommendation was to have as many tempdb data files as there are CPU cores on your server.  This no longer holds true due to the numerous cores we have on our servers.  Paul says you should start out with 1/4 to 1/2 the number of cores and work your way up from there.  BUT!  Paul likes what Bob Ward (twitter) says on this topic: 8 or less cores –> set number of files equal to the number of cores Greater than 8 cores –> start with 8 files and increase in blocks of 4 One common myth out there is to set your MAXDOP to 1 for an OLTP workload with high CXPACKET waits.  Instead of that, dig deeper first.  Look for missing indexes, out-of-date statistics, increase the “cost threshold for parallelism” setting, and perhaps set MAXDOP at the query level.  Paul stressed that you should not plan a backup strategy but instead plan a restore strategy.  What are your recoverability requirements?  Once you know that, now plan out your backups. As Paul always does, he talked about DBCC CHECKDB.  He said how fabulous it is.  I didn’t want to interrupt the presentation, so after his session had ended, I asked Paul about the need to run DBCC CHECKDB on your mirror systems.  You could have data corruption occur at the mirror and not at the principal server.  If you aren’t checking for data corruption on your mirror systems, you could be failing over to a corrupt database in the case of a disaster or even a planned failover.  You can’t run DBCC CHECKDB against the mirrored database, but you can run it against a snapshot off the mirrored database.

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