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• Creating a network link between 2 very close buildings

  - by Daniel Johnson

  I have a charity who have two adjacent medium sized modern detached houses (in the UK): the buildings stand next to each other and are less than 5 metres apart. They have DSL connected to a single computer in one of the buildings. They want to add a network with wireless, and want it to work across both buildings. Being a charity they need to keep costs down. The network would be used for sharing Word documents, e-mail, browsing and skyping. My initial thoughts were to connect the buildings with fibre. So: Option 1 Use fibre between the buildings. Sufficient cable and two TP-LINK MC100CM Fast Ethernet Media Converters. Cost ~£80.00. But there is the extra cost and hassle of running the cable down and up the external walls, lifting and relaying paving, and burying underground. Never having fitted fibre I'm also a little worried about going up the wall and then bending the cable at 90 degrees to go through the wall and into the building. Option 2 Use two TP-Link TL-WA7510N High Powered Outdoor 5Ghz 15dBi Wireless antennas to connect the buildings. There is a clear line of sight at first floor level. Cost ~£100. And much easier to fit than fibre! Is using the TL-WA7510Ns overkill? Is there something more suitable? I had hoped to use some Netgear stuff, e.g. two DGN2200, one in each house and also use them to provide the wireless link between the buildings. However, in bridge mode wireless client association is not available and repeater mode with client association only supports WEP security which isn't strong enough. Is there something similar that would be up to the job? Option 3 Connect the buildings with UTP cable. My concerns here are risk of electric shock due to a difference of potential between the buildings (or are they so close this shouldn't be an issue) and protection from lightning strikes. Is fitting lighting arrestors expensive? And what can be done to ameliorate against the risk of shock? This all falls outside my area of expertise so I would really appreciate some advice.

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• Local dedicated hosting space (own hardware)

  - by Scott

  Where can I find local dedicated hosting space for my own hardware? I know I can rent dedicated hosting from various companies online, but usually I think that means I'm renting their hardware too. I just need a space with a network connection and a power outlet. That's it. How much would this cost? What would I search for? Is it available easily? Or would it only be the sort of thing huge companies would do? I'm in the greater NYC area. It's for a project I'm working on, but the thing's loud and annoying. I'd be willing to pay a little to get it out of sight and out of mind. I don't even care too much about the quality of the network connection. I'd rather not rent other people's hardware cause it probably would cost a fortune to rent a machine like this (tons of ram).

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• Upload large database SQL file

  - by Devy

  I've a database of more than 20Gb of size on my hard disk. What is the best way to upload it with the least (money) load possible on the server? - I'm on Windows 7. - I have FTP and SSH access on the server. I avoid using FTP because my connection cuts off a lot, I can't imagine I re-upload again the file after failing on 99%. I found some tools that split the large .sql file to small .sql files, but they didn't mention how to gather these files again into one file. Another way is to archive the big .sql file to .rar with -v option, upload them through FTP then unpack them. But unpacking will also cost, right? I know it will cost in any cases, but any best practice will be strongly appreciated.

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• Help to argue why to develop software on a physical computer rather than via a remote desktop

  - by s5804

  Remote desktops are great and many times a blessing and cost effective (instead of leasing expensive cables). I am not arguing against remote desktops, just if one have the alternative to use either remote desktop or physical computer, I would choose the later. Also note that I am not arguing for or against remote work practices. But in my case I am required to be physically present in the office when developing software. Background, I work in a company which main business is not to develop software. Therefore the company IT policies are mainly focused on security and to efficiently deploying/maintaing thousands of computer to users. Further, the typical employee runs typical Office applications, like a word processors. Because safety/stability is such a big priority, every non production system/application, shall be deployed into a physical different network, called the test network. Software development of course also belongs in the test network. To access the test network the company has created a standard policy, which dictates that access to the test network shall go only via a remote desktop client. Practically from ones production computer one would open up a remote desktop client to a virtual computer located in the test network. On the virtual computer's remote desktop one would be able to access/run/install all development tools, like Eclipse IDE. Another solution would be to have a dedicated physical computer, which is physically only connected to the test network. Both solutions are available in the company. I have tested both approaches and found running Eclipse IDE, SQL developer, in the remote desktop client to be sluggish (keyboard strokes are delayed), commands like alt-tab takes me out of the remote client, enjoying... Further, screen resolution and colors are different, just to mention a few. Therefore there is nothing technical wrong with the remote client, just not optimal and frankly de-motivating. Now with the new policies put in place, plans are to remove the physical computers connected to the test network. I am looking for help to argue for why software developers shall have a dedicated physical software development computer, to be productive and cost effective. Remember that we are physically in office. Further one can notice that we are talking about approx. 50 computers out of 2000 employees. Therefore the extra budget is relatively small. This is more about policy than cost. Please note that there are lots of similar setups in other companies that work great due to a perfectly tuned systems. However, in my case it is sluggish and it would cost more money to trouble shoot the performance and fine tune it rather than to have a few physical computers. As a business case we have argued that productivity will go down by 25%, however it's my feeling that the reality is probably closer to 50%. This business case isn't really accepted and I find it very difficult to defend it to managers that has never ever used a rich IDE in their life, never mind developed software. Further the test network and remote client has no guaranteed service level, therefore it is down for a few hours per month with the lowest priority on the fix list. Help is appreciated.

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• Advice: Python Framework Server/Worker Queue management (not Website)

  - by Muppet Geoff

  I am looking for some advice/opinions of which Python Framework to use in an implementation of multiple 'Worker' PCs co-ordinated from a central Queue Manager. For completeness, the 'Worker' PCs will be running Audio Conversion routines (which I do not need advice on, and have standalone code that works). The Audio conversion takes a long time, and I need to co-ordinate an arbitrary number of the 'Workers' from a central location, handing them conversion tasks (such as where to get the source files, or where to ask for the job configuration) with them reporting back some additional info, such as the runtime of the converted audio etc. At present, I have a script that makes a webservice call to get the 'configuration' for a conversion task, based on source files located on the worker already (we manually copy the source files to the worker, and that triggers a conversion routine). I want to change this, so that we can distribute conversion tasks ("Oy you, process this: xxx") based on availability, and in an ideal world, based on pending tasks too. There is a chance that Workers can go offline mid-conversion (but this is not likely). All the workers are Windows based, the co-ordinator can be WIndows or Linux. I have (in my initial searches) come across the following - and I know that some are cross-dependent: Celery (with RabbitMQ) Twisted Django Using a framework, rather than home-brewing, seems to make more sense to me right now. I have a limited timeframe in which to develop this functional extension. An additional consideration would be using a Framework that is compatible with PyQT/PySide so that I can write a simple UI to display Queue status etc. I appreciate that the specifics above are a little vague, and I hope that someone can offer me a pointer or two. Again: I am looking for general advice on which Python framework to investigate further, for developing a Server/Worker 'Queue management' solution, for non-web activities (this is why DJango didn't seem the right fit).

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• C++ Optimize if/else condition

  - by Heye

  I have a single line of code, that consumes 25% - 30% of the runtime of my application. It is a less-than comparator for an std::set (the set is implemented with a Red-Black-Tree). It is called about 180 Million times within 52 seconds. struct Entry { const float _cost; const long _id; // some other vars Entry(float cost, float id) : _cost(cost), _id(id) { } }; template<class T> struct lt_entry: public binary_function <T, T, bool> { bool operator()(const T &l, const T &r) const { // Most readable shape if(l._cost != r._cost) { return r._cost < l._cost; } else { return l._id < r._id; } } }; The entries should be sorted by cost and if the cost is the same by their id. I have many insertions for each extraction of the minimum. I thought about using Fibonacci-Heaps, but I have been told that they are theoretically nice, but suffer from high constants and are pretty complicated to implement. And since insert is in O(log(n)) the runtime increase is nearly constant with large n. So I think its okay to stick to the set. To improve performance I tried to express it in different shapes: return l._cost < r._cost || r._cost > l._cost || l._id < r._id; return l._cost < r._cost || (l._cost == r._cost && l._id < r._id); Even this: typedef union { float _f; int _i; } flint; //... flint diff; diff._f = (l._cost - r._cost); return (diff._i && diff._i >> 31) || l._id < r._id; But the compiler seems to be smart enough already, because I haven't been able to improve the runtime. I also thought about SSE but this problem is really not very applicable for SSE... The assembly looks somewhat like this: movss (%rbx),%xmm1 mov $0x1,%r8d movss 0x20(%rdx),%xmm0 ucomiss %xmm1,%xmm0 ja 0x410600 <_ZNSt8_Rb_tree[..]+96> ucomiss %xmm0,%xmm1 jp 0x4105fd <_ZNSt8_Rb_[..]_+93> jne 0x4105fd <_ZNSt8_Rb_[..]_+93> mov 0x28(%rdx),%rax cmp %rax,0x8(%rbx) jb 0x410600 <_ZNSt8_Rb_[..]_+96> xor %r8d,%r8d I have a very tiny bit experience with assembly language, but not really much. I thought it would be the best (only?) point to squeeze out some performance, but is it really worth the effort? Can you see any shortcuts that could save some cycles? The platform the code will run on is an ubuntu 12 with gcc 4.6 (-stl=c++0x) on a many-core intel machine. Only libraries available are boost, openmp and tbb. I am really stuck on this one, it seems so simple, but takes that much time. I have been crunching my head since days thinking how I could improve this line... Can you give me a suggestion how to improve this part, or is it already at its best?

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• Accessing Instance Variables from NSTimer selector

  - by Timbo

  Firstly newbie question: What's the difference between a selector and a method? Secondly newbie question (who would have thought): I need to loop some code based on instance variables and pause between loops until some condition (of course based on instance variables) is met. I've looked at sleep, I've looked at NSThread. In both discussions working through those options many asked why don't I use NSTimer, so here I am. Ok so it's simple enough to get a method (selector? ) to fire on a schedule. Problem I have is that I don't know how to see instance variables I've set up outside the timer from within the code NSTimer fires. I need to see those variables from the NSTimer selector code as I 1) will be updating their values and 2) will set labels based on those values. Here's some code that shows the concept… eventually I'd invalidate the timers based on myVariable too, however I've excluded that for code clarity. MyClass *aMyClassInstance = [MyClass new]; [aMyClassInstance setMyVariable:0]; [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(doStuff) userInfo:nil repeats:YES]; [NSTimer scheduledTimerWithTimeInterval:5.0 target:self selector:@selector(doSomeOtherStuff) userInfo:nil repeats:YES]; - (void) doStuff { [aMyClassInstance setMyVariable:11]; // don't actually have access to set aMyClassInstance.myVariable [self updateSomeUILabel:[NSNumber numberWithInt:aMyClassInstance.myVariable]]; // don't actually have access to aMyClassInstance.myVariable } - (void) doSomeOtherStuff { [aMyClassInstance setMyVariable:22]; // don't actually have access to set aMyClassInstance.myVariable [self updateSomeUILabel:[NSNumber numberWithInt:aMyClassInstance.myVariable]]; // don't actually have access to aMyClassInstance.myVariable } - (void) updateSomeUILabel:(NSNumber *)arg{ int value = [arg intValue]; someUILabel.text = [NSString stringWithFormat:@"myVariable = %d", value]; // Updates the UI with new instance variable values }

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• Recommendations for SSD for server and database use?

  - by Tony_Henrich

  SSDs are a new technology and they are constantly improving. A lot of the posts here were posted in 2009 when SSDs where less mature and not as fast. What was recommend back then is probably out of date today because of better options. The SSD is used to hold SQL Server databases. Size is probably 128G. The database is used with a CMS and web server so web pages need to get their data and render as fast as possible. Which modern SSD is recommended for such a use? Is there an SSD better than Intel X-25 E/M in terms of performance/cost? (I am also evaluating cost between : RAM + UPS (semi persistent) vs SSD for same amount of gigabytes. No RAID is involved)

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• Multi-machine backup solutions

  - by Paul

  I have a growing number of PCs and laptops in my home that need a backup solution. My question is 2 fold: Most commercial backup vendors appear to license by the machine, are there any products that give a license that can be used on all your machines, without a per machine cost? An alternative is to have a centrally controlled back up strategy controlled from a single PC with an attached hard drive that can back up other machines on the network. What backup software is suitable for this approach? Will this software be windows/Linux interoperable? I've searched for duplicate questions but don't see anything that addresses the multi machine/cost issue. OSs in network will be Windows (XP, Vista, 7) and Linux variants. Not pattern to when machines will be switched on.

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• Why do SSD drives get so much more expensive as they get larger?

  - by futuraprime

  Normal HDD costs go up very little as drives get larger. For example, an average 1TB drive costs a little under $90, 2TB costs a little over $100, and a 3TB drive costs close to $150. For HDDs, the cost per GB goes down as the number of GB goes up. SSD costs don't work like this: a 128GB SSD goes for $120ish, 256GB goes for $250ish, and 512GB drives get up to $600. The cost per GB goes up as the number of GB rises. What is it about SSDs that makes them so much costlier as they get larger?

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• Designing for varying mobile device resolutions, i.e. iPhone 4 & iPhone 3G

  - by Josh

  As the design community moves to design applications & interfaces for mobile devices, a new problem has arisen: Varying Screen DPI's. Here's the situation: Touch: * iPhone 3G/S ~ 160 dpi * iPhone 4 ~ 300 dpi * iPad ~ 126 dpi * Android device @ 480p ~ 200 dpi Point / click: * Laptop @ 720p ~ 96 dpi * Desktop @ 720p ~ 72 dpi There is certainly a clear distinction between desktop and mobile so having two separate front-ends to the same app is logical, especially when considering one is "touch"-based and the other is "point/click"-based. The challenge lies in designing static graphical elements that will scale between, say, 160 dpi and 300+ dpi, and get consistent and clean design across zoom levels. Any thoughts on how to approach this? Here are some scenarios, but each has drawbacks as well: * Design a single set of assets (high resolution), then adjust zoom levels based on detected resolution / device o Drawbacks: Performance caused by code layering, varying device support of Zoom * Develop & optimize multiple variations of image and CSS assets, then hide / show each based on device o Drawbacks: Extra work in design & QA. Anyone have thoughts or experience on how to deal with this? We should certainly be looking at methods that use / support HTML5 and CSS3.

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• How to make one CPU to be used simulataneously be three different users

  - by beginning_steps

  As a bootstrapping start-up we are thinking of saving on the IT hardware cost by making more use of the hardware that we have. As a solopreneur I have a laptop config : intel core2duo processor, 3Gb RAM and 250 GB RAM. Now we are planning to increase our team to 3 members. Will like your suggestions on the nest cost-effective step that I can take so that I can use the computing power of the existing laptop to act as a kind of server and then buy to more monitors where the new recruits can do the daily work on and they need to have different login id and access and they dont need access to all the files/applications as are available in my laptop. We use internet intensively to do our day to day activity. Please share you experience, whether you think this is a good ploy or there is any other more effective way of achieving the same result.

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• Oracle Linux Forum

  - by rickramsey

  This forum includes live chat so you can tell Wim, Lenz, and the gang what you really think. Linux Forum - Tuesday March 27 Since Oracle recently made Release 2 of its Unbreakable Enterprise Kernel available (see Lenz's blog), we're following up with an online forum with Oracle's Linux executives and engineers. Topics will be: 9:30 - 9:45 am PT Oracle's Linux Strategy Edward Screven, Oracle's Chief Corporate Architect and Wim Coekaerts, Senior VP of Linux and Virtualization Engineering, will explain Oracle's Linux strategy, the benefits of Oracle Linux, Oracle's role in the Linux community, and the Oracle Linux roadmap. 9:45 - 10:00 am PT Why Progressive Insurance Chose Oracle Linux John Dome, Lead Systems Engineer at Progressive Insurance, outlines why they selected Oracle Linux with the Unbreakable Enterprise Kernel to reduce cost and increase the performance of database applications. 10:00 - 11:00 am PT What's New in Oracle Linux Oracle engineers walk you through new features in Oracle Linux, including zero-downtime updates with Ksplice, Btrfs and OCFS2, DTrace for Linux, Linux Containers, vSwitch and T-Mem. 11:00 am - 12:00 pm PT Get More Value from your Linux Vendor Why Oracle Linux delivers more value than Red Hat Enterprise Linux, including better support at lower cost, best practices for deployments, extreme performance for cloud deployments and engineered systems, and more. Date: Tuesday, March 27, 2012 Time: 9:30 AM PT / 12:30 PM ET Duration: 2.5 hours Register here. - Rick

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• Rush…iPAD Pre-order announced officially

  - by samsudeen

  Apple’s latest product iPAD is now available for pre-order through online. You can place your pre-order through its online store (Apple) or reserve it at any of the Apple retail stores. iPAD may have received mixed reactions when announced last month. But Apple knows how to sell; it is believed that more than 50,000 pre orders are already placed till now placed till now. People have to wait for another 3 weeks to get the actual device as the launch date is 3rd of April in the US. The initial model released will be available only with Wi-Fi and the planned 3G model is expected to be released by end of April. So how much does it cost you to get this little marvel? The basic iPAD (16 GB Wi-Fi) will cost you $499. if you are serious apple fan and plan to buy an iPAD better place your order now. There already rumours that the initial demand may outstrip supply.The pre-order is limited only to US. Join us on Facebook to read all our stories right inside your Facebook news feed.

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• Partner Webcast – More out of Database Appliance with DB Options - 13 September 2012

  - by Thanos

  The Oracle Database Appliance is a new way to take advantage of the world's most popular database—Oracle Database 11g —in a single, easy-to-deploy and manage system. It's a complete package of software, server, storage, and networking that's engineered for simplicity; saving time and money by simplifying deployment, maintenance, and support of database workloads. But that is not all, with the support for all Oracle Database Options, Oracle Database Appliance can be the ideal solution for many use cases. Feature Benefit Simplifies deployment, maintenance, and support of high-availability database workloads Saves significant time and effort throughout the database administration lifecycle An engineered system of software, server, storage, and networking High availability for a wide range of custom and packaged OLTP and data warehousing application databases Simple one-button Installation, full-stack integrated patching and diagnostics Reduces planned and unplanned downtime by automatically monitoring and logging service requests with Oracle Support Built using the world’s #1 database Protects databases from server and storage failures with Oracle Real Application Clusters and Automatic Storage Management Unique Pay-As-You-Grow software licensing Reduces cost with flexibility to adjust your software spend as your business grows without the need for any hardware upgrades Discover the Oracle Database Appliance Value Proposition and learn how to position and combine it with database options to capture new business and easily roll out solutions safely and with maximum cost efficiency. This webcast is repeated once again for your benefit. Agenda: Oracle Database& Engineered Systems Innovation. What’s the Oracle Database Appliance ? Oracle Database Appliance Value Proposition. Oracle Database Appliance with Database Options Oracle Database Appliance Partners Business Delivery FormatThis FREE online LIVE eSeminar will be delivered over the Web. Registrations received less than 24hours prior to start time may not receive confirmation to attend. Duration: 1 hour Register Now! Oracle Database Appliance is available for purchase at the Oracle Store under Engineered Systems. For any questions please contact us at partner.imc-AT-beehiveonline.oracle-DOT-com Visit regularly our ISV Migration Center blog Or Follow us @oracleimc to learn more on Oracle Technologies as well as upcoming partner webcasts and events.

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• SQL SERVER – PAGEIOLATCH_DT, PAGEIOLATCH_EX, PAGEIOLATCH_KP, PAGEIOLATCH_SH, PAGEIOLATCH_UP – Wait Type – Day 9 of 28

  - by pinaldave

  It is very easy to say that you replace your hardware as that is not up to the mark. In reality, it is very difficult to implement. It is really hard to convince an infrastructure team to change any hardware because they are not performing at their best. I had a nightmare related to this issue in a deal with an infrastructure team as I suggested that they replace their faulty hardware. This is because they were initially not accepting the fact that it is the fault of their hardware. But it is really easy to say “Trust me, I am correct”, while it is equally important that you put some logical reasoning along with this statement. PAGEIOLATCH_XX is such a kind of those wait stats that we would directly like to blame on the underlying subsystem. Of course, most of the time, it is correct – the underlying subsystem is usually the problem. From Book On-Line: PAGEIOLATCH_DT Occurs when a task is waiting on a latch for a buffer that is in an I/O request. The latch request is in Destroy mode. Long waits may indicate problems with the disk subsystem. PAGEIOLATCH_EX Occurs when a task is waiting on a latch for a buffer that is in an I/O request. The latch request is in Exclusive mode. Long waits may indicate problems with the disk subsystem. PAGEIOLATCH_KP Occurs when a task is waiting on a latch for a buffer that is in an I/O request. The latch request is in Keep mode. Long waits may indicate problems with the disk subsystem. PAGEIOLATCH_SH Occurs when a task is waiting on a latch for a buffer that is in an I/O request. The latch request is in Shared mode. Long waits may indicate problems with the disk subsystem. PAGEIOLATCH_UP Occurs when a task is waiting on a latch for a buffer that is in an I/O request. The latch request is in Update mode. Long waits may indicate problems with the disk subsystem. PAGEIOLATCH_XX Explanation: Simply put, this particular wait type occurs when any of the tasks is waiting for data from the disk to move to the buffer cache. ReducingPAGEIOLATCH_XX wait: Just like any other wait type, this is again a very challenging and interesting subject to resolve. Here are a few things you can experiment on: Improve your IO subsystem speed (read the first paragraph of this article, if you have not read it, I repeat that it is easy to say a step like this than to actually implement or do it). This type of wait stats can also happen due to memory pressure or any other memory issues. Putting aside the issue of a faulty IO subsystem, this wait type warrants proper analysis of the memory counters. If due to any reasons, the memory is not optimal and unable to receive the IO data. This situation can create this kind of wait type. Proper placing of files is very important. We should check file system for the proper placement of files – LDF and MDF on separate drive, TempDB on separate drive, hot spot tables on separate filegroup (and on separate disk), etc. Check the File Statistics and see if there is higher IO Read and IO Write Stall SQL SERVER – Get File Statistics Using fn_virtualfilestats. It is very possible that there are no proper indexes on the system and there are lots of table scans and heap scans. Creating proper index can reduce the IO bandwidth considerably. If SQL Server can use appropriate cover index instead of clustered index, it can significantly reduce lots of CPU, Memory and IO (considering cover index has much lesser columns than cluster table and all other it depends conditions). You can refer to the two articles’ links below previously written by me that talk about how to optimize indexes. Create Missing Indexes Drop Unused Indexes Updating statistics can help the Query Optimizer to render optimal plan, which can only be either directly or indirectly. I have seen that updating statistics with full scan (again, if your database is huge and you cannot do this – never mind!) can provide optimal information to SQL Server optimizer leading to efficient plan. Checking Memory Related Perfmon Counters SQLServer: Memory Manager\Memory Grants Pending (Consistent higher value than 0-2) SQLServer: Memory Manager\Memory Grants Outstanding (Consistent higher value, Benchmark) SQLServer: Buffer Manager\Buffer Hit Cache Ratio (Higher is better, greater than 90% for usually smooth running system) SQLServer: Buffer Manager\Page Life Expectancy (Consistent lower value than 300 seconds) Memory: Available Mbytes (Information only) Memory: Page Faults/sec (Benchmark only) Memory: Pages/sec (Benchmark only) Checking Disk Related Perfmon Counters Average Disk sec/Read (Consistent higher value than 4-8 millisecond is not good) Average Disk sec/Write (Consistent higher value than 4-8 millisecond is not good) Average Disk Read/Write Queue Length (Consistent higher value than benchmark is not good) 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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• Cloud MBaaS : The Next Big Thing in Enterprise Mobility

  - by shiju

  In this blog post, I will take a look at Cloud Mobile Backend as a Service (MBaaS) and how we can leverage Cloud based Mobile Backend as a Service for building enterprise mobile apps. Today, mobile apps are incredibly significant in both consumer and enterprise space and the demand for the mobile apps is unbelievably increasing in day to day business. An enterprise can’t survive in business without a proper mobility strategy. A better mobility strategy and faster delivery of your mobile apps will give you an extra mileage for your business and IT strategy. So organizations and mobile developers are looking for different strategy for meeting this demand and adopting different development strategy for their mobile apps. Some developers are adopting hybrid mobile app development platforms, for delivering their products for multiple platforms, for fast time-to-market. Others are adopting a Mobile enterprise application platform (MEAP) such as Kony for their enterprise mobile apps for fast time-to-market and better business integration. The Challenges of Enterprise Mobility The real challenge of enterprise mobile apps, is not about creating the front-end environment or developing front-end for multiple platforms. The most important thing of enterprise mobile apps is to expose your enterprise data to mobile devices where the real pain is your business data might be residing in lot of different systems including legacy systems, ERP systems etc., and these systems will be deployed with lot of security restrictions. Exposing your data from the on-premises servers, is not a easy thing for most of the business organizations. Many organizations are spending too much time for their front-end development strategy, but they are really lacking for building a strategy on their back-end for exposing the business data to mobile apps. So building a REST services layer and mobile back-end services, on the top of legacy systems and existing middleware systems, is the key part of most of the enterprise mobile apps, where multiple mobile platforms can easily consume these REST services and other mobile back-end services for building mobile apps. For some mobile apps, we can’t predict its user base, especially for products where customers can gradually increase at any time. And for today’s mobile apps, faster time-to-market is very critical so that spending too much time for mobile app’s scalability, will not be worth. The real power of Cloud is the agility and on-demand scalability, where we can scale-up and scale-down our applications very easily. It would be great if we could use the power of Cloud to mobile apps. So using Cloud for mobile apps is a natural fit, where we can use Cloud as the storage for mobile apps and hosting mechanism for mobile back-end services, where we can enjoy the full power of Cloud with greater level of on-demand scalability and operational agility. So Cloud based Mobile Backend as a Service is great choice for building enterprise mobile apps, where enterprises can enjoy the massive scalability power of their mobile apps, provided by public cloud vendors such as Microsoft Windows Azure. Mobile Backend as a Service (MBaaS) We have discussed the key challenges of enterprise mobile apps and how we can leverage Cloud for hosting mobile backend services. MBaaS is a set of cloud-based, server-side mobile services for multiple mobile platforms and HTML5 platform, which can be used as a backend for your mobile apps with the scalability power of Cloud. The information below provides the key features of a typical MBaaS platform: Cloud based storage for your application data. Automatic REST API services on the application data, for CRUD operations. Native push notification services with massive scalability power. User management services for authenticate users. User authentication via Social accounts such as Facebook, Google, Microsoft, and Twitter. Scheduler services for periodically sending data to mobile devices. Native SDKs for multiple mobile platforms such as Windows Phone and Windows Store, Android, Apple iOS, and HTML5, for easily accessing the mobile services from mobile apps, with better security.  Typically, a MBaaS platform will provide native SDKs for multiple mobile platforms so that we can easily consume the server-side mobile services. MBaaS based REST APIs can use for integrating to enterprise backend systems. We can use the same mobile services for multiple platform so hat we can reuse the application logic to multiple mobile platforms. Public cloud vendors are building the mobile services on the top of their PaaS offerings. Windows Azure Mobile Services is a great platform for a MBaaS offering that is leveraging Windows Azure Cloud platform’s PaaS capabilities. Hybrid mobile development platform Titanium provides their own MBaaS services. LoopBack is a new MBaaS service provided by Node.js consulting firm StrongLoop, which can be hosted on multiple cloud platforms and also for on-premises servers. The Challenges of MBaaS Solutions If you are building your mobile apps with a new data storage, it will be very easy, since there is not any integration challenges you have to face. But most of the use cases, you have to extract your application data in which stored in on-premises servers which might be under VPNs and firewalls. So exposing these data to your MBaaS solution with a proper security would be a big challenge. The capability of your MBaaS vendor is very important as you have to interact with your legacy systems for many enterprise mobile apps. So you should be very careful about choosing for MBaaS vendor. At the same time, you should have a proper strategy for mobilizing your application data which stored in on-premises legacy systems, where your solution architecture and strategy is more important than platforms and tools.  Windows Azure Mobile Services Windows Azure Mobile Services is an MBaaS offerings from Windows Azure cloud platform. IMHO, Microsoft Windows Azure is the best PaaS platform in the Cloud space. Windows Azure Mobile Services extends the PaaS capabilities of Windows Azure, to mobile devices, which can be used as a cloud backend for your mobile apps, which will provide global availability and reach for your mobile apps. Windows Azure Mobile Services provides storage services, user management with social network integration, push notification services and scheduler services and provides native SDKs for all major mobile platforms and HTML5. In Windows Azure Mobile Services, you can write server-side scripts in Node.js where you can enjoy the full power of Node.js including the use of NPM modules for your server-side scripts. In the previous section, we had discussed some challenges of MBaaS solutions. You can leverage Windows Azure Cloud platform for solving many challenges regarding with enterprise mobility. The entire Windows Azure platform can play a key role for working as the backend for your mobile apps where you can leverage the entire Windows Azure platform for your mobile apps. With Windows Azure, you can easily connect to your on-premises systems which is a key thing for mobile backend solutions. Another key point is that Windows Azure provides better integration with services like Active Directory, which makes Windows Azure as the de facto platform for enterprise mobility, for enterprises, who have been leveraging Microsoft ecosystem for their application and IT infrastructure. Windows Azure Mobile Services  is going to next evolution where you can expect some exciting features in near future. One area, where Windows Azure Mobile Services should definitely need an improvement, is about the default storage mechanism in which currently it is depends on SQL Server. IMHO, developers should be able to choose multiple default storage option when creating a new mobile service instance. Let’s say, there should be a different storage providers such as SQL Server storage provider and Table storage provider where developers should be able to choose their choice of storage provider when creating a new mobile services project. I have been used Windows Azure and Windows Azure Mobile Services as the backend for production apps for mobile, where it performed very well. MBaaS Over MEAP Recently, many larger enterprises has been adopted Mobile enterprise application platform (MEAP) for their mobile apps. I haven’t worked on any production MEAP solution, but I heard that developers are really struggling with MEAP in different way. The learning curve for a proprietary MEAP platform is very high. I am completely against for using larger proprietary ecosystem for mobile apps. For enterprise mobile apps, I highly recommend to use native iOS/Android/Windows Phone or HTML5  for front-end with a cloud hosted MBaaS solution as the middleware. A MBaaS service can be consumed from multiple mobile apps where REST APIs are using to integrating with enterprise backend systems. Enterprise mobility should start with exposing REST APIs on the enterprise backend systems and these REST APIs can host on Cloud where we can enjoy the power of Cloud for our services. If you are having REST APIs for your enterprise data, then you can easily build mobile frontends for multiple platforms.   You can follow me on Twitter @shijucv

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• Design Book–Fourth(last) Section (Physical Abstraction Optimization)

  - by drsql

  In this last section of the book, we will shift focus to the physical abstraction layer optimization. By this I mean the little bits and pieces of the design that is specifically there for performance and are actually part of the relational engine (read: the part of the SQL Server experience that ideally is hidden from you completely, but in 2010 reality it isn’t quite so yet.  This includes all of the data structures like database, files, etc; the optimizer; some coding, etc. In my mind, this...(read more)

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• Making Money from your SQL Server Blog

  - by Bill Graziano

  My SQL Server blog reading list is around one hundred blogs.  Many people are writing great content and generating lots of page views.  I see some of them running Google AdSense and trying to make a little money off their traffic.  If you want to earn some some extra money from what you’ve written there are a couple of options.  And one new option that I’m announcing here. Background Internet advertising is sold based on a few different pricing schemes.  Flat Fee.  You offer either all your impressions (page views) or some percentage of your impressions in exchange for a flat monthly fee.  CPM or cost per thousand impressions.  If the quoted price is $2 CPM you’ll get $2 for every 1,000 times the ad is displayed.  While you might think the “M” means millions, the “M” in CPM is the roman numeral for 1,000. CPC or cost per click.  This is also called PPC or pay per click.  In this method you get paid based on how many clicks there are on the ad.  CPA or cost per action.  In this method you get paid based on an action that occurs on the advertisers site after they click on the ad.  This is typically some type of sign up form.  This is how most affiliate programs work. Darren Rowse at ProBlogger has been writing about blogging and making money off blogs for years.  He has a good introduction to making money on your blog in his “Making Money” section.  If you’re interested in learning more he has a post up titled How to Make More Money From Your Blog in the New Year that links to many of his best posts on the subject. Google AdSense This is the most common method for people earning money from their blogging.  It’s easy to setup and administer.  You tell AdSense what size ads you’d like to run and it gives you a little piece of JavaScript to put on your site.  AdSense quickly learns the topics you write about and displays ads that are appropriate for your site.  I typically see ads for hosting, SQL Server tools and developer tools running in AdSense slots.  AdSense pays on a CPC model.  If you translate that back to CPM pricing you’ll see rates from $0.50 to $1.00 CPM. Amazon While you might not make much money writing books it’s now possible to make even less helping Amazon sell them.  You can sign up for an Amazon affiliate program.  Each time you send Amazon a link and someone buys the book you get a cut of that sale.  This is the CPA model from above.  Amazon can help you build some pretty nice “stores”.  Here’s the SQL Server bookstore I built for SQLTeam.com.  If you’re just putting in a page with books like I’ve done on SQLTeam you should keep your expectations low.  If you’re writing book reviews of suggesting books on your blog it really does make sense to setup an Amazon affiliate link.  People are much more likely to buy a book based on a review from a trusted source.  I always try to buy through a referral link if there is one. Amazon pays about 4% of the price as a referral fee.  You also get credit for anything else they buy while on the site.  I recently had someone buy an iPod nano with their SQL Server book making me an extra $5.60 richer!  Estimating how much you can make is difficult though.  How much attention you draw to the links and book reviews can dramatically affect the earnings. Private Ad Sales This is the hardest but potentially most lucrative option.  You sell advertising directly to companies that want to sell things to your readers.  Typically this would be SQL Server tool vendors, hosting companies or anyone else that wants to make money off database administrators.  This is also the most difficult to do.  You’ll need the contacts at the companies and enough page views to make it worth their while.  You’ll also need software to track the page views and clicks, geo-target your ads and smooth out the impressions.  Your earnings are based on whatever you can negotiate with the companies. SQL Server Ad Network For the last couple of years I’ve run any extra ads that I sold on the SQLTeam Weblogs.  You can see an example of that on Mladen’s blog.  The ad in the upper right corner is one that I’m running for him.  (Note: Many of the ads I’m running are geo-targeted to only appear in English speaking countries.  You may see a different set of ads outside the US, Canada and the UK.  You can also see he has a couple of Google ads on his blog.)  When I run ads on his blog I split the advertising revenue with him.  They make a little and I make a little. I recently started to expand this and sell advertising specifically to run on SQL Server-related blogs.  I’m also starting to run ads on non-SQLTeam blogs.  The only way I can sell more advertising is to have more blogs to run it on.  And that’s where you come in. I’ve created a SQL Server advertising network.  I handle all the ad sales and provide the technology to serve the ads.  I handle collections and payments back to you.  You get paid at the end of each month regardless of when (or if) the advertiser actually pays.  All you need to do is add a small piece of JavaScript to your site to display the ads. If you’re writing about SQL Server and interested in earning a little money for your site I’d like to talk to you.  You can use the Contact Us page on SQLTeam.com to reach me.  Running advertising on your blog isn’t for everyone.  If you’re concerned about what advertisers might think about certain posts then you might not be a good fit.  For the most part this isn’t an issue.  You’ll also need to have a PayPal account to receive payments.  You probably won’t get rich doing this.  But you can earn extra cash on the side for doing what you would do anyway.  I do know that people have earned enough to buy themselves a nice laptop doing this. My initial target is blogs with more than 10,000 page views per month.  I expect to pay two to three times what Google pays.  If you have less than 10,000 page views per month but are still interested I’d still like to hear from you.  I may not be able to sign up smaller blogs right away but we’ll get the process started.  If you’re unsure about your traffic Google Analytics is a free tool that provides great reporting on traffic, popular posts and how people find your blog.  If you have any questions or are just curious drop me a line and I’ll try to answer your questions.

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• Why is IaaS important in Azure&hellip;

  - by Steve Loethen

  Three weeks ago, Microsoft released the next phase of Azure.  I have had several clients waiting on this release.  The fact that they have been waiting and are now more receptive to looking at the cloud.  Customers expressed fear of the unknown.  And a fear of lack of control, even when that lack of control also means a huge degree of flexibility to innovate with concerns about the underlying infrastructure.  I think IaaS will be that “gateway drug” to get customers who have been hesitant to take another look at the cloud.  The dialog can change from the cloud being this big scary unknown to a resource for workloads.  The conversations should have always been, and can know be even stronger, geared toward the following points: 1) The cloud is not unicorns and glitter, the cloud is resources.  Compute, storage, db’s, services bus, cache…..  Like many of the resources we have on-premise.  Not magic, just another resource with advantages and obstacles like any other resource. 2) The cloud should be part of the conversation for any new project.  All of the same criteria should be applied, on-premise or off.  Cost, security, reliability, scalability, speed to deploy, cost of licenses, need to customize image, complex workloads.  We have been having these discussions for years when we talk about on-premise projects.  We make decisions on OS’s, Databases, ESB’s, configuration and products based on a myriad of factors.  We use the same factors but now we have a additional set of resources to consider in our process. 3) The cloud is a great solution looking for some interesting problems.  It is our job to recognize the right problems that fit into the cloud, weigh the factors and decide what to do. IaaS makes this discussion easier, offers more choices, and often choices that many enterprises will find more better than PaaS.  Looking forward to helping clients realize the power of the cloud.

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• SQL SERVER – Introduction to SQL Server 2014 In-Memory OLTP

  - by Pinal Dave

  In SQL Server 2014 Microsoft has introduced a new database engine component called In-Memory OLTP aka project “Hekaton” which is fully integrated into the SQL Server Database Engine. It is optimized for OLTP workloads accessing memory resident data. In-memory OLTP helps us create memory optimized tables which in turn offer significant performance improvement for our typical OLTP workload. The main objective of memory optimized table is to ensure that highly transactional tables could live in memory and remain in memory forever without even losing out a single record. The most significant part is that it still supports majority of our Transact-SQL statement. Transact-SQL stored procedures can be compiled to machine code for further performance improvements on memory-optimized tables. This engine is designed to ensure higher concurrency and minimal blocking. In-Memory OLTP alleviates the issue of locking, using a new type of multi-version optimistic concurrency control. It also substantially reduces waiting for log writes by generating far less log data and needing fewer log writes. Points to remember Memory-optimized tables refer to tables using the new data structures and key words added as part of In-Memory OLTP. Disk-based tables refer to your normal tables which we used to create in SQL Server since its inception. These tables use a fixed size 8 KB pages that need to be read from and written to disk as a unit. Natively compiled stored procedures refer to an object Type which is new and is supported by in-memory OLTP engine which convert it into machine code, which can further improve the data access performance for memory –optimized tables. Natively compiled stored procedures can only reference memory-optimized tables, they can’t be used to reference any disk –based table. Interpreted Transact-SQL stored procedures, which is what SQL Server has always used. Cross-container transactions refer to transactions that reference both memory-optimized tables and disk-based tables. Interop refers to interpreted Transact-SQL that references memory-optimized tables. Using In-Memory OLTP In-Memory OLTP engine has been available as part of SQL Server 2014 since June 2013 CTPs. Installation of In-Memory OLTP is part of the SQL Server setup application. The In-Memory OLTP components can only be installed with a 64-bit edition of SQL Server 2014 hence they are not available with 32-bit editions. Creating Databases Any database that will store memory-optimized tables must have a MEMORY_OPTIMIZED_DATA filegroup. This filegroup is specifically designed to store the checkpoint files needed by SQL Server to recover the memory-optimized tables, and although the syntax for creating the filegroup is almost the same as for creating a regular filestream filegroup, it must also specify the option CONTAINS MEMORY_OPTIMIZED_DATA. Here is an example of a CREATE DATABASE statement for a database that can support memory-optimized tables: CREATE DATABASE InMemoryDB ON PRIMARY(NAME = [InMemoryDB_data], FILENAME = 'D:\data\InMemoryDB_data.mdf', size=500MB), FILEGROUP [SampleDB_mod_fg] CONTAINS MEMORY_OPTIMIZED_DATA (NAME = [InMemoryDB_mod_dir], FILENAME = 'S:\data\InMemoryDB_mod_dir'), (NAME = [InMemoryDB_mod_dir], FILENAME = 'R:\data\InMemoryDB_mod_dir') LOG ON (name = [SampleDB_log], Filename='L:\log\InMemoryDB_log.ldf', size=500MB) COLLATE Latin1_General_100_BIN2; Above example code creates files on three different drives (D:  S: and R:) for the data files and in memory storage so if you would like to run this code kindly change the drive and folder locations as per your convenience. Also notice that binary collation was specified as Windows (non-SQL). BIN2 collation is the only collation support at this point for any indexes on memory optimized tables. It is also possible to add a MEMORY_OPTIMIZED_DATA file group to an existing database, use the below command to achieve the same. ALTER DATABASE AdventureWorks2012 ADD FILEGROUP hekaton_mod CONTAINS MEMORY_OPTIMIZED_DATA; GO ALTER DATABASE AdventureWorks2012 ADD FILE (NAME='hekaton_mod', FILENAME='S:\data\hekaton_mod') TO FILEGROUP hekaton_mod; GO Creating Tables There is no major syntactical difference between creating a disk based table or a memory –optimized table but yes there are a few restrictions and a few new essential extensions. Essentially any memory-optimized table should use the MEMORY_OPTIMIZED = ON clause as shown in the Create Table query example. DURABILITY clause (SCHEMA_AND_DATA or SCHEMA_ONLY) Memory-optimized table should always be defined with a DURABILITY value which can be either SCHEMA_AND_DATA or  SCHEMA_ONLY the former being the default. A memory-optimized table defined with DURABILITY=SCHEMA_ONLY will not persist the data to disk which means the data durability is compromised whereas DURABILITY= SCHEMA_AND_DATA ensures that data is also persisted along with the schema. Indexing Memory Optimized Table A memory-optimized table must always have an index for all tables created with DURABILITY= SCHEMA_AND_DATA and this can be achieved by declaring a PRIMARY KEY Constraint at the time of creating a table. The following example shows a PRIMARY KEY index created as a HASH index, for which a bucket count must also be specified. CREATE TABLE Mem_Table ( [Name] VARCHAR(32) NOT NULL PRIMARY KEY NONCLUSTERED HASH WITH (BUCKET_COUNT = 100000), [City] VARCHAR(32) NULL, [State_Province] VARCHAR(32) NULL, [LastModified] DATETIME NOT NULL, ) WITH (MEMORY_OPTIMIZED = ON, DURABILITY = SCHEMA_AND_DATA); Now as you can see in the above query example we have used the clause MEMORY_OPTIMIZED = ON to make sure that it is considered as a memory optimized table and not just a normal table and also used the DURABILITY Clause= SCHEMA_AND_DATA which means it will persist data along with metadata and also you can notice this table has a PRIMARY KEY mentioned upfront which is also a mandatory clause for memory-optimized tables. We will talk more about HASH Indexes and BUCKET_COUNT in later articles on this topic which will be focusing more on Row and Index storage on Memory-Optimized tables. So stay tuned for that as well. Now as we covered the basics of Memory Optimized tables and understood the key things to remember while using memory optimized tables, let’s explore more using examples to understand the Performance gains using memory-optimized tables. I will be using the database which i created earlier in this article i.e. InMemoryDB in the below Demo Exercise. USE InMemoryDB GO -- Creating a disk based table CREATE TABLE dbo.Disktable ( Id INT IDENTITY, Name CHAR(40) ) GO CREATE NONCLUSTERED INDEX IX_ID ON dbo.Disktable (Id) GO -- Creating a memory optimized table with similar structure and DURABILITY = SCHEMA_AND_DATA CREATE TABLE dbo.Memorytable_durable ( Id INT NOT NULL PRIMARY KEY NONCLUSTERED Hash WITH (bucket_count =1000000), Name CHAR(40) ) WITH (MEMORY_OPTIMIZED = ON, DURABILITY = SCHEMA_AND_DATA) GO -- Creating an another memory optimized table with similar structure but DURABILITY = SCHEMA_Only CREATE TABLE dbo.Memorytable_nondurable ( Id INT NOT NULL PRIMARY KEY NONCLUSTERED Hash WITH (bucket_count =1000000), Name CHAR(40) ) WITH (MEMORY_OPTIMIZED = ON, DURABILITY = SCHEMA_only) GO -- Now insert 100000 records in dbo.Disktable and observe the Time Taken DECLARE @i_t bigint SET @i_t =1 WHILE @i_t<= 100000 BEGIN INSERT INTO dbo.Disktable(Name) VALUES('sachin' + CONVERT(VARCHAR,@i_t)) SET @i_t+=1 END -- Do the same inserts for Memory table dbo.Memorytable_durable and observe the Time Taken DECLARE @i_t bigint SET @i_t =1 WHILE @i_t<= 100000 BEGIN INSERT INTO dbo.Memorytable_durable VALUES(@i_t, 'sachin' + CONVERT(VARCHAR,@i_t)) SET @i_t+=1 END -- Now finally do the same inserts for Memory table dbo.Memorytable_nondurable and observe the Time Taken DECLARE @i_t bigint SET @i_t =1 WHILE @i_t<= 100000 BEGIN INSERT INTO dbo.Memorytable_nondurable VALUES(@i_t, 'sachin' + CONVERT(VARCHAR,@i_t)) SET @i_t+=1 END The above 3 Inserts took 1.20 minutes, 54 secs, and 2 secs respectively to insert 100000 records on my machine with 8 Gb RAM. This proves the point that memory-optimized tables can definitely help businesses achieve better performance for their highly transactional business table and memory- optimized tables with Durability SCHEMA_ONLY is even faster as it does not bother persisting its data to disk which makes it supremely fast. Koenig Solutions is one of the few organizations which offer IT training on SQL Server 2014 and all its updates. Now, I leave the decision on using memory_Optimized tables on you, I hope you like this article and it helped you understand  the fundamentals of IN-Memory OLTP . Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL Tagged: Koenig

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• Company Review: Google Products

  Google, Inc offers an array of products and services to all of its end-users. However their search capabilities are the foundation for Google’s current success and their primary business focus. Currently, Google offers over twenty different search applications that allow users to search the internet for books, maps, videos, images, products and much more. Their product decisions have allowed users demands to be met while focusing on the free based model. This allows users to access Google data free of charge and indirectly gives Google a strong competitive advantage of other competitors along with the accuracy of the search results. According to Google, Inc, they offer the following types of searching capabilities: Alerts Get email updates on the topics of your choice Blog Search Find blogs on your favorite topics  Books Search the full text of books  Custom Search Create a customized search experience for your community  Desktop Search and personalize your computer  Dictionary Search for definitions of words and phrases Directory Search the web, organized by topic or category Earth Explore the world from your computer Finance Business info, news and interactive charts GOOG-411 Find and connect for free with businesses from your phone  Images Search for images on the web Maps View maps and directions News Search thousands of news stories Patent Search Search the full text of US Patents Product Search Search for stuff to buy Scholar Search scholarly papers Toolbar Add a search box to your browser Trends Explore past and present search trends Videos Search for videos on the web Web Search Search billions of web pages Web Search Features Find movies, music, stocks, books and more mapping Google’s free based business model is only one way it differentiates itself from its competition. There is also a strong focus on the accuracy of search results and the speed in which they are returned to the end-user. Quality function deployment (QFD) is a structured method used to help connect user needs to the design features of a project proposed to address those needs. This method is particularly useful in accounting for needs that are not easily articulated or precisely defined according to the U. S. Department of Transportation Federal Highway Administration. Due to the fact that QFD is so customer driven Google is always in a constant state of change in attempt to reengineer its search algorithms, and other dependant systems so that end-users requirements are constantly being met. Value engineering is a key example of this, Google is constantly trying to improve all aspects of its products, improve system maintainability, and system interoperability. Bridgefield Group defines value engineering as an organized methodology that identifies and selects the lowest lifecycle cost options in design, materials and processes that achieves the desired level of performance, reliability and customer satisfaction. In addition, it seeks to remove unnecessary costs in the above areas and is often a joint effort with cross-functional internal teams and relevant suppliers. Common issues that appear when developing large scale systems like Google’s search applications include modular design of a product and/or service and providing accurate value analysis. A design approach that adheres to four fundamental tenets of cohesiveness, encapsulation, self-containment, and high binding to design a system component as an independently operable unit subject to change is how the Open System Joint Task Force defines modular design. More specifically M. S. Schmaltz defines modular software design as having a large collection of statements strung together in one partition of in-line code; we segment or divide the statements into logical groups called modules. Each module performs one or two tasks, and then passes control to another module. By breaking up the code into "bite-sized chunks", so to speak, we are able to better control the flow of data and control. This is especially true in large software systems. Value analysis is a process to evaluate products and services based on effectiveness, safety, and cost. Value analysis involves assessing the quality as well as the cost of a product or service as defined by the Healthcare Financial Management Association.  “Operations Management deals with the design and management of products, processes, services and supply chains. It considers the acquisition, development, and utilization of resources that firms need to deliver the goods and services their clients want.” (MIT,2010) Google, Inc encourages an open environment between all employees, also known as Googlers. This is reinforced by a cross-section team or cross-functional teams comprised from multiple departments assigned to every project so that every department like marketing, finance, and quality assurance has input on every project. In addition, Google is known for their openness to new ideas regardless of the status or seniority of an employee. In fact, Google allows for 20% of an employee’s time can be devoted to developing new ideas and/or pet projects. HumTech.com defines a cross-functional team as a collection of people with varied levels of skills and experience brought together to accomplish a task. As the name implies, Cross-Functional Team members come from different organizational units. Cross-Functional Teams may be permanent or ad hoc. Google’s search application product strategy primarily focuses on mass customization. This is allows Google to create a base search application and allows results to be returned to the end-users quickly based on specific parameters and search settings. In addition, they also store the data that is returned in case other desire the same results based on other end-users supplying the same customized settings. This allows Google to appear to render search results in virtually real-time to the user while allowing for complete customization of the searching criteria. Greg Vogl, a professor at Uganda Martyrs University, defines mass customization as when a business gives its customers the opportunity to tailor its products or services to the customer's specifications. The IT staff at Google play a key role in ensuring that the search application’s product strategy is maintained simply because the IT staff designs, develops, and maintains all of their proprietary applications. In fact, they also maintain all network infrastructure to ensure that it is available to all end-users. References: http://www.google.com/intl/en/options/ http://ops.fhwa.dot.gov/freight/publications/ftat_user_guide/sec5.htm http://www.bridgefieldgroup.com/bridgefieldgroup/glos9.htm#V http://www.acq.osd.mil/osjtf/termsdef.html http://www.cise.ufl.edu/~mssz/Pascal-CGS2462/prog-dsn.html http://www.hfma.org/publications/business_caring_newsletter/exclusives/Supply+and+Inventory+Terms+Defined.htm http://mitsloan.mit.edu/omg/om-definition.php http://www.humtech.com/opm/grtl/ols/ols3.cfm http://www.gregvogl.net/courses/mis1/glossary.htm

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• Is Berkeley DB a NoSQL solution?

  - by Gregory Burd

  Berkeley DB is a library. To use it to store data you must link the library into your application. You can use most programming languages to access the API, the calls across these APIs generally mimic the Berkeley DB C-API which makes perfect sense because Berkeley DB is written in C. The inspiration for Berkeley DB was the DBM library, a part of the earliest versions of UNIX written by AT&T's Ken Thompson in 1979. DBM was a simple key/value hashtable-based storage library. In the early 1990s as BSD UNIX was transitioning from version 4.3 to 4.4 and retrofitting commercial code owned by AT&T with unencumbered code, it was the future founders of Sleepycat Software who wrote libdb (aka Berkeley DB) as the replacement for DBM. The problem it addressed was fast, reliable local key/value storage. At that time databases almost always lived on a single node, even the most sophisticated databases only had simple fail-over two node solutions. If you had a lot of data to store you would choose between the few commercial RDBMS solutions or to write your own custom solution. Berkeley DB took the headache out of the custom approach. These basic market forces inspired other DBM implementations. There was the "New DBM" (ndbm) and the "GNU DBM" (GDBM) and a few others, but the theme was the same. Even today TokyoCabinet calls itself "a modern implementation of DBM" mimicking, and improving on, something first created over thirty years ago. In the mid-1990s, DBM was the name for what you needed if you were looking for fast, reliable local storage. Fast forward to today. What's changed? Systems are connected over fast, very reliable networks. Disks are cheep, fast, and capable of storing huge amounts of data. CPUs continued to follow Moore's Law, processing power that filled a room in 1990 now fits in your pocket. PCs, servers, and other computers proliferated both in business and the personal markets. In addition to the new hardware entire markets, social systems, and new modes of interpersonal communication moved onto the web and started evolving rapidly. These changes cause a massive explosion of data and a need to analyze and understand that data. Taken together this resulted in an entirely different landscape for database storage, new solutions were needed. A number of novel solutions stepped up and eventually a category called NoSQL emerged. The new market forces inspired the CAP theorem and the heated debate of BASE vs. ACID. But in essence this was simply the market looking at what to trade off to meet these new demands. These new database systems shared many qualities in common. There were designed to address massive amounts of data, millions of requests per second, and scale out across multiple systems. The first large-scale and successful solution was Dynamo, Amazon's distributed key/value database. Dynamo essentially took the next logical step and added a twist. Dynamo was to be the database of record, it would be distributed, data would be partitioned across many nodes, and it would tolerate failure by avoiding single points of failure. Amazon did this because they recognized that the majority of the dynamic content they provided to customers visiting their web store front didn't require the services of an RDBMS. The queries were simple, key/value look-ups or simple range queries with only a few queries that required more complex joins. They set about to use relational technology only in places where it was the best solution for the task, places like accounting and order fulfillment, but not in the myriad of other situations. The success of Dynamo, and it's design, inspired the next generation of Non-SQL, distributed database solutions including Cassandra, Riak and Voldemort. The problem their designers set out to solve was, "reliability at massive scale" so the first focal point was distributed database algorithms. Underneath Dynamo there is a local transactional database; either Berkeley DB, Berkeley DB Java Edition, MySQL or an in-memory key/value data structure. Dynamo was an evolution of local key/value storage onto networks. Cassandra, Riak, and Voldemort all faced similar design decisions and one, Voldemort, choose Berkeley DB Java Edition for it's node-local storage. Riak at first was entirely in-memory, but has recently added write-once, append-only log-based on-disk storage similar type of storage as Berkeley DB except that it is based on a hash table which must reside entirely in-memory rather than a btree which can live in-memory or on disk. Berkeley DB evolved too, we added high availability (HA) and a replication manager that makes it easy to setup replica groups. Berkeley DB's replication doesn't partitioned the data, every node keeps an entire copy of the database. For consistency, there is a single node where writes are committed first - a master - then those changes are delivered to the replica nodes as log records. Applications can choose to wait until all nodes are consistent, or fire and forget allowing Berkeley DB to eventually become consistent. Berkeley DB's HA scales-out quite well for read-intensive applications and also effectively eliminates the central point of failure by allowing replica nodes to be elected (using a PAXOS algorithm) to mastership if the master should fail. This implementation covers a wide variety of use cases. MemcacheDB is a server that implements the Memcache network protocol but uses Berkeley DB for storage and HA to replicate the cache state across all the nodes in the cache group. Google Accounts, the user authentication layer for all Google properties, was until recently running Berkeley DB HA. That scaled to a globally distributed system. That said, most NoSQL solutions try to partition (shard) data across nodes in the replication group and some allow writes as well as reads at any node, Berkeley DB HA does not. So, is Berkeley DB a "NoSQL" solution? Not really, but it certainly is a component of many of the existing NoSQL solutions out there. Forgetting all the noise about how NoSQL solutions are complex distributed databases when you boil them down to a single node you still have to store the data to some form of stable local storage. DBMs solved that problem a long time ago. NoSQL has more to do with the layers on top of the DBM; the distributed, sometimes-consistent, partitioned, scale-out storage that manage key/value or document sets and generally have some form of simple HTTP/REST-style network API. Does Berkeley DB do that? Not really. Is Berkeley DB a "NoSQL" solution today? Nope, but it's the most robust solution on which to build such a system. Re-inventing the node-local data storage isn't easy. A lot of people are starting to come to appreciate the sophisticated features found in Berkeley DB, even mimic them in some cases. Could Berkeley DB grow into a NoSQL solution? Absolutely. Our key/value API could be extended over the net using any of a number of existing network protocols such as memcache or HTTP/REST. We could adapt our node-local data partitioning out over replicated nodes. We even have a nice query language and cost-based query optimizer in our BDB XML product that we could reuse were we to build out a document-based NoSQL-style product. XML and JSON are not so different that we couldn't adapt one to work with the other interchangeably. Without too much effort we could add what's missing, we could jump into this No SQL market withing a single product development cycle. Why isn't Berkeley DB already a NoSQL solution? Why aren't we working on it? Why indeed...

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• SQL SERVER – Guest Post by Sandip Pani – SQL Server Statistics Name and Index Creation

  - by pinaldave

  Sometimes something very small or a common error which we observe in daily life teaches us new things. SQL Server Expert Sandip Pani (winner of Joes 2 Pros Contests) has come across similar experience. Sandip has written a guest post on an error he faced in his daily work. Sandip is working for QSI Healthcare as an Associate Technical Specialist and have more than 5 years of total experience. He blogs at SQLcommitted.com and contribute in various forums. His social media hands are LinkedIn, Facebook and Twitter. Once I faced following error when I was working on performance tuning project and attempt to create an Index. Mug 1913, Level 16, State 1, Line 1 The operation failed because an index or statistics with name ‘Ix_Table1_1′ already exists on table ‘Table1′. The immediate reaction to the error was that I might have created that index earlier and when I researched it further I found the same as the index was indeed created two times. This totally makes sense. This can happen due to many reasons for example if the user is careless and executes the same code two times as well, when he attempts to create index without checking if there was index already on the object. However when I paid attention to the details of the error, I realize that error message also talks about statistics along with the index. I got curious if the same would happen if I attempt to create indexes with the same name as statistics already created. There are a few other questions also prompted in my mind. I decided to do a small demonstration of the subject and build following demonstration script. The goal of my experiment is to find out the relation between statistics and the index. Statistics is one of the important input parameter for the optimizer during query optimization process. If the query is nontrivial then only optimizer uses statistics to perform a cost based optimization to select a plan. For accuracy and further learning I suggest to read MSDN. Now let’s find out the relationship between index and statistics. We will do the experiment in two parts. i) Creating Index ii) Creating Statistics We will be using the following T-SQL script for our example. IF (OBJECT_ID('Table1') IS NOT NULL) DROP TABLE Table1 GO CREATE TABLE Table1 (Col1 INT NOT NULL, Col2 VARCHAR(20) NOT NULL) GO We will be using following two queries to check if there are any index or statistics on our sample table Table1. -- Details of Index SELECT OBJECT_NAME(OBJECT_ID) AS TableName, Name AS IndexName, type_desc FROM sys.indexes WHERE OBJECT_NAME(OBJECT_ID) = 'table1' GO -- Details of Statistics SELECT OBJECT_NAME(OBJECT_ID) TableName, Name AS StatisticsName FROM sys.stats WHERE OBJECT_NAME(OBJECT_ID) = 'table1' GO When I ran above two scripts on the table right after it was created it did not give us any result which was expected. Now let us begin our test. 1) Create an index on the table Create following index on the table. CREATE NONCLUSTERED INDEX Ix_Table1_1 ON Table1(Col1) GO Now let us use above two scripts and see their results. We can see that when we created index at the same time it created statistics also with the same name. Before continuing to next set of demo – drop the table using following script and re-create the table using a script provided at the beginning of the table. DROP TABLE table1 GO 2) Create a statistic on the table Create following statistics on the table. CREATE STATISTICS Ix_table1_1 ON Table1 (Col1) GO Now let us use above two scripts and see their results. We can see that when we created statistics Index is not created. The behavior of this experiment is different from the earlier experiment. Clean up the table setup using the following script: DROP TABLE table1 GO Above two experiments teach us very valuable lesson that when we create indexes, SQL Server generates the index and statistics (with the same name as the index name) together. Now due to the reason if we have already had statistics with the same name but not the index, it is quite possible that we will face the error to create the index even though there is no index with the same name. A Quick Check To validate that if we create statistics first and then index after that with the same name, it will throw an error let us run following script in SSMS. Make sure to drop the table and clean up our sample table at the end of the experiment. -- Create sample table CREATE TABLE TestTable (Col1 INT NOT NULL, Col2 VARCHAR(20) NOT NULL) GO -- Create Statistics CREATE STATISTICS IX_TestTable_1 ON TestTable (Col1) GO -- Create Index CREATE NONCLUSTERED INDEX IX_TestTable_1 ON TestTable(Col1) GO -- Check error /*Msg 1913, Level 16, State 1, Line 2 The operation failed because an index or statistics with name 'IX_TestTable_1' already exists on table 'TestTable'. */ -- Clean up DROP TABLE TestTable GO While creating index it will throw the following error as statistics with the same name is already created. In simple words – when we create index the name of the index should be different from any of the existing indexes and statistics. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Error Messages, SQL Index, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: SQL Statistics

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• Code excavations, wishful invocations, perimeters and domain specific unit test frameworks

  - by RoyOsherove

  One of the talks I did at QCON London was about a subject that I’ve come across fairly recently , when I was building SilverUnit – a “pure” unit test framework for silverlight objects that depend on the silverlight runtime to run. It is the concept of “cogs in the machine” – when your piece of code needs to run inside a host framework or runtime that you have little or no control over for testability related matters. Examples of such cogs and machines can be: your custom control running inside silverlight runtime in the browser your plug-in running inside an IDE your activity running inside a windows workflow your code running inside a java EE bean your code inheriting from a COM+ (enterprise services) component etc.. Not all of these are necessarily testability problems. The main testability problem usually comes when your code actually inherits form something inside the system. For example. one of the biggest problems with testing objects like silverlight controls is the way they depend on the silverlight runtime – they don’t implement some silverlight interface, they don’t just call external static methods against the framework runtime that surrounds them – they actually inherit parts of the framework: they all inherit (in this case) from the silverlight DependencyObject Wrapping it up? An inheritance dependency is uniquely challenging to bring under test, because “classic” methods such as wrapping the object under test with a framework wrapper will not work, and the only way to do manually is to create parallel testable objects that get delegated with all the possible actions from the dependencies.    In silverlight’s case, that would mean creating your own custom logic class that would be called directly from controls that inherit from silverlight, and would be tested independently of these controls. The pro side is that you get the benefit of understanding the “contract” and the “roles” your system plays against your logic, but unfortunately, more often than not, it can be very tedious to create, and may sometimes feel unnecessary or like code duplication. About perimeters A perimeter is that invisible line that your draw around your pieces of logic during a test, that separate the code under test from any dependencies that it uses. Most of the time, a test perimeter around an object will be the list of seams (dependencies that can be replaced such as interfaces, virtual methods etc.) that are actually replaced for that test or for all the tests. Role based perimeters In the case of creating a wrapper around an object – one really creates a “role based” perimeter around the logic that is being tested – that wrapper takes on roles that are required by the code under test, and also communicates with the host system to implement those roles and provide any inputs to the logic under test. in the image below – we have the code we want to test represented as a star. No perimeter is drawn yet (we haven’t wrapped it up in anything yet). in the image below is what happens when you wrap your logic with a role based wrapper – you get a role based perimeter anywhere your code interacts with the system: There’s another way to bring that code under test – using isolation frameworks like typemock, rhino mocks and MOQ (but if your code inherits from the system, Typemock might be the only way to isolate the code from the system interaction.   Ad-Hoc Isolation perimeters the image below shows what I call ad-hoc perimeter that might be vastly different between different tests: This perimeter’s surface is much smaller, because for that specific test, that is all the “change” that is required to the host system behavior.   The third way of isolating the code from the host system is the main “meat” of this post: Subterranean perimeters Subterranean perimeters are Deep rooted perimeters  - “always on” seams that that can lie very deep in the heart of the host system where they are fully invisible even to the test itself, not just to the code under test. Because they lie deep inside a system you can’t control, the only way I’ve found to control them is with runtime (not compile time) interception of method calls on the system. One way to get such abilities is by using Aspect oriented frameworks – for example, in SilverUnit, I’ve used the CThru AOP framework based on Typemock hooks and CLR profilers to intercept such system level method calls and effectively turn them into seams that lie deep down at the heart of the silverlight runtime. the image below depicts an example of what such a perimeter could look like: As you can see, the actual seams can be very far away form the actual code under test, and as you’ll discover, that’s actually a very good thing. Here is only a partial list of examples of such deep rooted seams : disabling the constructor of a base class five levels below the code under test (this.base.base.base.base) faking static methods of a type that’s being called several levels down the stack: method x() calls y() calls z() calls SomeType.StaticMethod()  Replacing an async mechanism with a synchronous one (replacing all timers with your own timer behavior that always Ticks immediately upon calls to “start()” on the same caller thread for example) Replacing event mechanisms with your own event mechanism (to allow “firing” system events) Changing the way the system saves information with your own saving behavior (in silverunit, I replaced all Dependency Property set and get with calls to an in memory value store instead of using the one built into silverlight which threw exceptions without a browser) several questions could jump in: How do you know what to fake? (how do you discover the perimeter?) How do you fake it? Wouldn’t this be problematic  - to fake something you don’t own? it might change in the future How do you discover the perimeter to fake? To discover a perimeter all you have to do is start with a wishful invocation. a wishful invocation is the act of trying to invoke a method (or even just create an instance ) of an object using “regular” test code. You invoke the thing that you’d like to do in a real unit test, to see what happens: Can I even create an instance of this object without getting an exception? Can I invoke this method on that instance without getting an exception? Can I verify that some call into the system happened? You make the invocation, get an exception (because there is a dependency) and look at the stack trace. choose a location in the stack trace and disable it. Then try the invocation again. if you don’t get an exception the perimeter is good for that invocation, so you can move to trying out other methods on that object. in a future post I will show the process using CThru, and how you end up with something close to a domain specific test framework after you’re done creating the perimeter you need.

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