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  • How can I find out which user deleted a directory?

    - by Rob S.
    My Ubuntu server has about roughly 30 active users on it. I personally know everyone using the server. Recently, a few friends and I were working on project. We made a new directory for the project and since everyone knows everyone we didn't bother protecting our work under a bunch of permissions. We should have though, because we woke up this morning to find that someone removed our entire directory. Our work is backed up every night so it's really not a big deal to restore our work. However, we would like to find out who removed it so we can confront them. So far the best thing we've come up with for finding our culprit is checking everyone's bash history but this is long and tedious and chances are that if there was a malicious intent behind the directory removal that our culprit probably modified theirs to cover their tracks (or of course they might use a different shell). So, basically, what is the easiest and quickest way to find out who deleted a directory? Thanks in advance for your time.

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  • DAO/Webservice Consumption in Web Application

    - by Gavin
    I am currently working on converting a "legacy" web-based (Coldfusion) application from single data source (MSSQL database) to multi-tier OOP. In my current system there is a read/write database with all the usual stuff and additional "read-only" databases that are exported daily/hourly from an Enterprise Resource Planning (ERP) system by SSIS jobs with business product/item and manufacturing/SCM planning data. The reason I have the opportunity and need to convert to multi-tier OOP is a newer more modern ERP system is being implemented business wide that will be a complete replacement. This newer ERP system offers several interfaces for third party applications like mine, from direct SQL access to either a dotNet web-service or a SOAP-like web-service. I have found several suitable frameworks I would be happy to use (Coldspring, FW/1) but I am not sure what design patterns apply to my data access object/component and how to manage the connection/session tokens, with this background, my question has the following three parts: Firstly I have concerns with moving from the relative safety of a SSIS job that protects me from downtime and speed of the ERP system to directly connecting with one of the web services which I note seem significantly slower than I expected (simple/small requests often take up to a whole second). Are there any design patterns I can investigate/use to cache/protect my data tier? It is my understanding data access objects (the component that connects directly with the web services and convert them into the data types I can then work with in my Domain Objects) should be singletons (and will act as an Adapter/Facade), am I correct? As part of the data access object I have to setup a connection by username/password (I could set up multiple users and/or connect multiple times with this) which responds with a session token that needs to be provided on every subsequent request. Do I do this once and share it across the whole application, do I setup a new "connection" for every user of my application and keep the token in their session scope (might quickly hit licensing limits), do I set the "connection" up per page request, or is there a design pattern I am missing that can manage multiple "connections" where a requests/access uses the first free "connection"? It is worth noting if the ERP system dies I will need to reset/invalidate all the connections and start from scratch, and depending on which web-service I use might need manually close the "connection/session"

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  • Programming and Ubiquitous Language (DDD) in a non-English domain

    - by Sandor Drieënhuizen
    I know there are some questions already here that are closely related to this subject but none of them take Ubquitous Language as the starting point so I think that justifies this question. For those who don't know: Ubiquitous Language is the concept of defining a (both spoken and written) language that is equally used across developers and domain experts to avoid inconsistencies and miscommunication due to translation problems and misunderstanding. You will see the same terminology show up in code, conversations between any team member, functional specs and whatnot. So, what I was wondering about is how to deal with Ubiquitous Language in non-English domains. Personally, I strongly favor writing programming code in English completely, including comments but ofcourse excluding constants and resources. However, in a non-English domain, I'm forced to make a decision either to: Write code reflecting the Ubiquitous Language in the natural language of the domain. Translate the Ubiquitous Language to English and stop communicating in the natural language of the domain. Define a table that defines how the Ubiquitous Language translates to English. Here are some of my thoughts based on these options: 1) I have a strong aversion against mixed-language code, that is coding using type/member/variable names etc. that are non-English. Most programming languages 'breathe' English to a large extent and most of the technical literature, design pattern names etc. are in English as well. Therefore, in most cases there's just no way of writing code entirely in a non-English language so you end up with a mixed languages. 2) This will force the domain experts to start thinking and talking in the English equivalent of the UL, something that will probably not come naturally to them and therefore hinders communication significantly. 3) In this case, the developers communicate with the domain experts in their native language while the developers communicate with each other in English and most importantly, they write code using the English translation of the UL. I'm sure I don't want to go for the first option and I think option 3 is much better than option 2. What do you think? Am I missing other options?

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  • Constructs for wrapping a hardware state machine

    - by Henry Gomersall
    I am using a piece of hardware with a well defined C API. The hardware is stateful, with the relevant API calls needing to be in the correct order for the hardware to work properly. The API calls themselves will always return, passing back a flag that advises whether the call was successful, or if not, why not. The hardware will not be left in some ill defined state. In effect, the API calls advise indirectly of the current state of the hardware if the state is not correct to perform a given operation. It seems to be a pretty common hardware API style. My question is this: Is there a well established design pattern for wrapping such a hardware state machine in a high level language, such that consistency is maintained? My development is in Python. I ideally wish the hardware state machine to be abstracted to a much simpler state machine and wrapped in an object that represents the hardware. I'm not sure what should happen if an attempt is made to create multiple objects representing the same piece of hardware. I apologies for the slight vagueness, I'm not very knowledgeable in this area and so am fishing for assistance of the description as well!

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  • Is there an established or defined best practice for source control branching between development and production builds?

    - by Matthew Patrick Cashatt
    Thanks for looking. I struggled in how to phrase my question, so let me give an example in hopes of making more clear what I am after: I currently work on a dev team responsible for maintaining and adding features to a web application. We have a development server and we use source control (TFS). Each day everyone checks in their code and when the code (running on the dev server) passes our QA/QC program, it goes to production. Recently, however, we had a bug in production which required an immediate production fix. The problem was that several of us developers had code checked in that was not ready for production so we had to either quickly complete and QA the code, or roll back everything, undo pending changes, etc. In other words, it was a mess. This made me wonder: Is there an established design pattern that prevents this type of scenario. It seems like there must be some "textbook" answer to this, but I am unsure what that would be. Perhaps a development branch of the code and a "release-ready" or production branch of the code?

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  • Getting rid of Massive View Controller in iOS?

    - by Earl Grey
    I had a discussion with my colleague about the following problem. We have an application where we need filtering functionality. On any main screen within the upper navigation bar, there is a button in the upper right corner. Once you touch that button, an custom written Alert View like view will pop up modally, behind it a semitransparent black overlay view. In that modal view, there is a table view of options, and you can choose one exclusively. Based on your selection, once this modal view is closed, the list of items in the main view is filtered. It is simply a modally presented filter to filter the main table view.This UI design is dictated by the design department, I cannot do anything about it so let accept this as a premise. Also the main filter button in the navbar will change colours to indicate that the filter is active. The question I have is about implementation. I suggested to my colleague that we create a separate XYZFilter class that will be an instance created by the main view controller acquire the filtering options handle saving and restoration of its state - i.e. last filter selected provide its two views - the overlay view and the modal view be the datasource for the table in its modal view. For some unknown reason, my colleague was not impressed by that approach at all. He simply wants to do these functionalities in the main view controller, maybe out of being used to do this in the past like that :-/ Is there any fundamental problem with my approach? I want to keep the view controller small, not to have spaghetti code create a reusable component (for use outside the project) have more object oriented, decoupled approach. prevent duplication of code as we need the filtering in two different places but it looks the same in both.. Any advice?

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  • How To Change Window Transparency in Windows 7 with a Hotkey

    - by YatriTrivedi
    Linux has a lot of eye-candy because of Compiz, my favorite of which is the window opacity plugin. Using a short AutoHotKey script, you can add that same functionality to Windows 7. I used this AHK script as a basis for changing opacity. It uses a single hotkey to change the active window’s transparency by 25% each time until it resets to 0. I wanted functionality similar to Compiz, so I modified the script to use the mouse wheel and shortened the increments to get more variety. Just hold down the Windows key and scroll down to see through the window. This decreases opacity and makes windows more transparent. Latest Features How-To Geek ETC Learn To Adjust Contrast Like a Pro in Photoshop, GIMP, and Paint.NET Have You Ever Wondered How Your Operating System Got Its Name? Should You Delete Windows 7 Service Pack Backup Files to Save Space? What Can Super Mario Teach Us About Graphics Technology? Windows 7 Service Pack 1 is Released: But Should You Install It? How To Make Hundreds of Complex Photo Edits in Seconds With Photoshop Actions Hack Apart a Highlighter to Create UV-Reactive Flowers [Science] Add a “Textmate Style” Lightweight Text Editor with Dropbox Syncing to Chrome and Iron Is the Forcefield Really On or Not? [Star Wars Parody Video] Google Updates Picasa Web Albums; Emphasis on Sharing and Showcasing Uwall.tv Turns YouTube into a Video Jukebox Early Morning Sunrise at the Beach Wallpaper

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  • Read On Phone Pushes Data from Your Desktop to the Appropriate Android App

    - by ETC
    Read On Phone is a free Android application that intelligently pushes data to your phone from your bowser. Rather than simply opening the URL on your phone, it opens the appropriate application for the task and formats text. Most send-to-phone type tools simply take the URL of the web page you’re looking at on your computer and shuttle it to your phone. Read On Phone is a more active and effective tool. When you send a page that is text, it formats the text for easy reading on your phone. When you send a YouTube video, map, or telephone number, it opens up the appropriate tool on your phone such as your YouTube viewer, Google Maps, or your phone dialer. In addition to that handy functionality Read On Phone also includes adjustments for day and night reading, font size, auto-scrolling, and pagination. Read On Phone is available as both a Chrome extension and as a bookmarklet for cross-browser use. Hit up the link below for additional information. Read On Phone Latest Features How-To Geek ETC Should You Delete Windows 7 Service Pack Backup Files to Save Space? What Can Super Mario Teach Us About Graphics Technology? Windows 7 Service Pack 1 is Released: But Should You Install It? How To Make Hundreds of Complex Photo Edits in Seconds With Photoshop Actions How to Enable User-Specific Wireless Networks in Windows 7 How to Use Google Chrome as Your Default PDF Reader (the Easy Way) Read On Phone Pushes Data from Your Desktop to the Appropriate Android App MetroTwit is a Sleek Native Twitter Client for Your Windows System Make Efficient Use of Tab Bar Space by Customizing Tab Width in Firefox See the Geeky Work Done Behind the Scenes to Add Sounds to Movies [Video] Use a Crayon to Enhance Engraved Lettering on Electronics Adult Swim Brings Their Programming Lineup to iOS Devices

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  • Configuration tools for multiple monitors for X / Linux

    - by richard
    I have Ubuntu 10.04 running gnome and two monitors. I am wondering if a can get a better multi-monitor configuration tool. The one I have, gnome-display-properties, has too many problems, including: When I swapped my monitors over, the narrower (external) one now on the left. There is a width calculation error, such that I have a virtual monitor the width of the wide-monitor on the narrow-monitor and part of the wide monitor. And a virtual narrow-monitor on the remainder of the wide-monitor. Also the visible mouse pointer does is not aligned with the active spot, an x offset of one monitor width. I would like, in approximate order of importance: nobugs. to be able to select which is primary monitor. to have multiple configurations. configurations to be automatically selected based on which monitors are attached. configurations to be cycled (reliably) when display mode key is pressed. when a display is deactivated, for windows to migrate to remaining monitors. option to not change display resolution when mirroring, but to use side/top blanking bars to pad out screen.

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  • Thank you South Florida for a successful SPSouthFLA

    - by Leonard Mwangi
    I wanted to officially thank the organizers, speakers, volunteers and the attendees of SharePoint Saturday South Florida. Being the first event in South Florida the reception was phenomenon and the group of speakers from keynote by Joel Oleson to session’s speakers from well renowned speakers like John Holliday, Randy Disgrill, Richard Harbridge, Ameet Phadnis, Fabian Williams, Chris McNulty, Jaime Velez to organizers like Michael Hinckley amongst others. With my Business Intelligence (BI) presentation being on the last track of the day, I spent very quality time networking with these great guys and getting the insider scope on International SharePoint Community from Joel and his son which was mesmerizing. I had a very active audience to a point where we couldn’t accommodate all the contents within the 1hr allocated time because they were very engaged and wanted a deep dive session on news features like PowerPivot, enhancements on PerformancePoint, Excel Services amongst others in order to understand the business value and how SharePoint 2010 is making the self-service BI become a reality. These community events allows the attendees experience technology first hand and network with MVPs, authors, experts providing high quality educational sessions usually for free which is a reason to attend. I have made the slides for my session available for download for those interested http://goo.gl/VaH5x

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  • Mailbox move issue from Exchange 2003 to Exchange 2010

    - by Ryan Roussel
    Today while moving mailboxes between Exchange 2003 and Exchange 2010, I hit an issue with a couple of mailboxes.  These mailboxes all popped access denied errors or more exactly: Insufficient Access Rights to perform the operation.   The cause was similar to the mail flow issue in that inheritable permissions were not turned on for the user object in Active Directory.  This also presented it’s own unique problem in that since the initial move request failed because of permissions, it had to be cleared before a new move request could be created. On top of that, the request did not show up in the EMC.  I used the following process to clear the request, assign permission, then create a new request:   1. First you need to know the ExchangeGUID of the mailbox for the remove-moverequest command.  To quickly get the GUID for a mailbox simply run:         2. Next we need to clear out the move request using PowerShell by running: [PS] c:\>Remove-moverequest -moverequestqueue "mailbox database 1030639620" -mailboxguid 8525686f-d4d3-42b7-92f1-46d77ea841a3   3. Then to re-establish inheritable permissions. This can be done by using AD Users and Computers, switching to View Advanced Features, then under the Security tab of the object.  Click Advanced, then check “allow inheritable permissions of parent to propagate to this object”   4. Once the Inheritable permissions are restored, we need to create a new move request: NOTE:  The EMC can also be used to initiate the Move Request once the permissions are corrected. [PS] c:\>New-moverequest –identity jyoung  -baditemlimit 100 -targetdatabase "mailbox database 1030639620"   And that’s it.  The mailbox should move over smoothly with no access denied error.

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  • responsibility for storage

    - by Stefano Borini
    A colleague and I were brainstorming about where to put the responsibility of an object to store itself on the disk in our own file format. There are basically two choices: object.store(file) fileformatWriter.store(object) The first one gives the responsibility of serialization on the disk to the object itself. This is similar to the approach used by python pickle. The second groups the representation responsibility on a file format writer object. The data object is just a plain data container (eventually with additional methods not relevant for storage). We agreed on the second methodology, because it centralizes the writing logic from generic data. We also have cases of objects implementing complex logic that need to store info while the logic is in progress. For these cases, the fileformatwriter object can be passed and used as a delegate, calling storage operations on it. With the first pattern, the complex logic object would instead accept the raw file, and implement the writing logic itself. The first method, however, has the advantage that the object knows how to write and read itself from any file containing it, which may also be convenient. I would like to hear your opinion before starting a rather complex refactoring.

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  • Show Notes: Debra Lilley on Fusion Applications

    - by Bob Rhubart
    The latest ArchBeat program features a three-part interview with Oracle ACE Director Debra Lilley (ACE Profile). Debra is Oracle Alliance Director at Fujitsu, Executive Member at the International Oracle Users Group Community (IOUG), Director and Deputy Chair at the UK Oracle Users Group (UKOUG), and a partner at Oracle UK.  So yeah, she’s connected.  In this interview Debra talks about her connection to Oracle Fusion Applications. Listen to Part 1 Debra talks about her role as the as the Director and Deputy Chairperson of the UKOUG and about the UKOUG development group’s involvement in Oracle Fusion Applications. Listen to Part 2 (March 9) Debra shares her insight into what Fusion Applications will bring to Enterprise Architecture, and the importance of user experience in enterprise architecture. Listen to Part 3 (March 16) Debra discusses the need to  close the gap between IT and business, and about how business users should be able to use applications without having to think about the underlying technology. Debra is very active in social networks, so if you have questions or comments you can connect with her via the following: Blog: http://www.debrasoracle.blogspot.com/ Twitter: @debralilley LinkedIn:  http://uk.linkedin.com/pub/debra-lilley/1/438/bba And if you’d like to learn more about Oracle Fusion Applications: http://www.oracle.com/us/products/applications/fusion/index.html Coming Soon Dr. Frank Munz, author of Middleware and Cloud Computing: Oracle Fusion Middleware on Amazon Web Services and Rackspace Cloud.  Andy MacMillan (VP, Enterprise 2.0, Oracle) on the socialization of the enterprise. A panel discussion on “Who gets to be a software architect?” Stay tuned: RSS Technorati Tags: oracle,fusion applications,enterprise architecture,IOUG,UKOUG del.icio.us Tags: oracle,fusion applications,enterprise architecture,IOUG,UKOUG

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  • Reflecting on 2010 and Looking into 2011

    - by Sam Abraham
    In early 2010, I had blogged and shared my excitement as I was about to embark on a new journey relocating to South Florida.     As I settled down and adjusted to my new life, I was presented with an opportunity to get actively involved and volunteer in the local Florida .Net and Project Management communities.  I have since devoted a significant portion of my time to community initiatives, coordinating the West Palm Beach .Net User Group, volunteering as a member of the INETA Speaker’s Bureau and traveling to attend/speak at .Net code camps and user groups throughout the states of Florida and New York. I have also taken on various volunteer roles at the South Florida Chapter of the Project Management Institute starting as core team member on the chapter’s mentoring initiative and ending the year as Project Manager of the chapter’s mentoring program and as Director of Electronic Communications on the chapter’s IT team. I am also serving a one year term (2010-2011) as secretary and founding board member of Florida’s first official chapter of the International Association for Software Architects (IASA).   A big thank you is due for those who afforded me the opportunity and privilege to take part of these initiatives and those who provided guidance and encouragement when I needed them the most.   Looking ahead into 2011, I hope to continue my community involvement and volunteer activities. I will start by dedicating the first 5 weekends in the New Year to teach a free comprehensive Microsoft PowerPoint class at church. My goal will be to start from scratch and slowly cover the various available PowerPoint features that can be leveraged to create captivating presentations. Starting February, I will be resuming my user group/code camp speaking engagements at our South Florida .Net Code Camp and the West Palm Beach .Net User Group.   I look forward to continuing to meet, chat and share with our technical community members and to another active year in community service.   All the best, --Sam Abraham

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  • Reading a large SQL Errorlog

    - by steveh99999
    I came across an interesting situation recently where a SQL instance had been configured with the Audit of successful and failed logins being written to the errorlog. ie This meant… every time a user or the application connected to the SQL instance – an entry was written to the errorlog. This meant…  huge SQL Server errorlogs. Opening an errorlog in the usual way, using SQL management studio, was extremely slow… Luckily, I was able to use xp_readerrorlog to work around this – here’s some example queries..   To show errorlog entries from the currently active log, just for today :- DECLARE @now DATETIME DECLARE @midnight DATETIME SET @now = GETDATE() SET @midnight =  DATEADD(d, DATEDIFF(d, 0, getdate()), 0) EXEC xp_readerrorlog 0,1,NULL,NULL,@midnight,@now   To find out how big the current errorlog actually is, and what the earliest and most recent entries are in the errorlog :- CREATE TABLE #temp_errorlog (Logdate DATETIME, ProcessInfo VARCHAR(20),Text VARCHAR(4000)) INSERT INTO #temp_errorlog EXEC xp_readerrorlog 0 -- for current errorlog SELECT COUNT(*) AS 'Number of entries in errorlog', MIN(logdate) AS 'ErrorLog Starts', MAX(logdate) AS 'ErrorLog Ends' FROM #temp_errorlog DROP TABLE #temp_errorlog To show just DBCC history  information in the current errorlog :- EXEC xp_readerrorlog 0,1,'dbcc'   To show backup errorlog entries in the current errorlog :- CREATE TABLE #temp_errorlog (Logdate DATETIME, ProcessInfo VARCHAR(20),Text VARCHAR(4000)) INSERT INTO #temp_errorlog EXEC xp_readerrorlog 0 -- for current errorlog SELECT * from #temp_errorlog WHERE ProcessInfo = 'Backup' ORDER BY Logdate DROP TABLE #temp_errorlog XP_Errorlog is an undocumented system stored procedure – so no official Microsoft link describing the parameters it takes – however,  there’s a good blog on this here And, if you do have a problem with huge errorlogs – please consider running system stored procedure  sp_cycle_errorlog on a nightly or regular basis.  But if you do this,  remember to change the amount of errorlogs you do retain – the default of 6 might not be sufficient for you….

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  • Is it possible to execute keyboard input programmatically in Linux?

    - by Taylor Hawkes
    For example is there a Linux command or way that I could from a program (c++ | python| or other) enter a series of keyboard inputs that are interpreted as though they are keyboard inputs. I have a bad case of Repetitive Stress Injury (RSI) from typing. To ease my pain I developed a voice controlled interface using pocket sphinx and a custom grammar and to run a number of very common commands. ex: "open chrome" , "open vim". Basically what is shown here, but with slightly diff tools: http://bloc.eurion.net/archives/2008/writing-a-command-and-control-application-with-voice-recognition/ I have run into some limitation as I can only execute command line commands given a voice command. Rather than having a "voice command" - "command line command" mapping, I would like to have "voice command" - "keyboard input" mapping. So when my active window is a browser and I type + n, and new tab opens. If I'm in vim and new vim tab opens. Any suggestions, ideas, tools or approaches to this problem would be much appreciated. I understand the answer may not be simple, but would like to develop it none the less.

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  • Delivering Oracle DBaaS: Journey to Enterprise Cloud with Oracle Database 12c

    - by B R Clouse
    The release of Oracle Database 12c  is accompanied by extensive supporting collateral that details the new features and options of this major release.  But with so much to read and investigate, where to start?  If you don't have the time to pore through everything, then you may wish organize your reading in terms of the use case you're most interested in.  If your interest is Database as a Service in private database clouds then may I suggest that you start here: Accelerate the Journey to Enterprise Cloud with Oracle Database 12c Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-family:"Calibri","sans-serif"; mso-ascii- mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi- mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} This paper describes the phases of the journey to enterprise cloud, and enumerates the new features and options in Oracle Database 12c that support each phase.  Oracle Multitenant figures prominently, but it's not the only cloud-enabling topic: Oracle Database Quality of Service Management, Application Continuity, Automatic Data Optimization, Global Data Services and Active Data Guard Far Sync all deliver key benefits for delivering database as a service.  Further reading and research is suggested by the references included in the paper. Happy clouding!

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  • Fixing SharePoint 2010 Permission Problems on Windows 7

    - by Ricardo Peres
    I had a tough time trying to have SharePoint working perfectly on a Windows 7 development machine that was occasionally disconnected from the Active Directory (when I am home I must connect through a VPN). I mostly had problems with service applications such as User Profile, Managed Metadata, Business Connectivity Services and the like, and all I knew were cryptical messages such as “access denied” or “the service or application pool is not started”. I was sure that both the services and application pools were running under a domain account that had proper permissions on the SQL Server instance, and basically it was a fresh installation. Lots of people are having the same problem, apparently. After banging my head against the wall for several days, I remembered about farm (what I had) versus stand-alone (which I had never tried) installations. Bingo! Here’s what I did: I dropped all SharePoint databases and logins and reinstalled SP from scratch, only this time not in farm mode, but as stand-alone. After the SharePoint Configuration Wizard started, I cancelled it and started the Management Shell. I created the configuration database manually by using the New-SPConfigurationDatabase cmdlet where I specified a local account – something that the Configuration Wizard wouldn’t allow me to do. Then I restarted the Configuration Wizard and everything began working perfectly! Yes, I got some pre-configured service applications and also some content which I didn’t need, but I realized it was possible to drop and recreate everything the way I wanted to. All services and application pools are now running under local accounts, which is fine for my development needs. Really, Microsoft… I hope this will bring light to someone facing the same problems!

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  • Changes to the LINQ-to-StreamInsight Dialect

    - by Roman Schindlauer
    In previous versions of StreamInsight (1.0 through 2.0), CepStream<> represents temporal streams of many varieties: Streams with ‘open’ inputs (e.g., those defined and composed over CepStream<T>.Create(string streamName) Streams with ‘partially bound’ inputs (e.g., those defined and composed over CepStream<T>.Create(Type adapterFactory, …)) Streams with fully bound inputs (e.g., those defined and composed over To*Stream – sequences or DQC) The stream may be embedded (where Server.Create is used) The stream may be remote (where Server.Connect is used) When adding support for new programming primitives in StreamInsight 2.1, we faced a choice: Add a fourth variety (use CepStream<> to represent streams that are bound the new programming model constructs), or introduce a separate type that represents temporal streams in the new user model. We opted for the latter. Introducing a new type has the effect of reducing the number of (confusing) runtime failures due to inappropriate uses of CepStream<> instances in the incorrect context. The new types are: IStreamable<>, which logically represents a temporal stream. IQStreamable<> : IStreamable<>, which represents a queryable temporal stream. Its relationship to IStreamable<> is analogous to the relationship of IQueryable<> to IEnumerable<>. The developer can compose temporal queries over remote stream sources using this type. The syntax of temporal queries composed over IQStreamable<> is mostly consistent with the syntax of our existing CepStream<>-based LINQ provider. However, we have taken the opportunity to refine certain aspects of the language surface. Differences are outlined below. Because 2.1 introduces new types to represent temporal queries, the changes outlined in this post do no impact existing StreamInsight applications using the existing types! SelectMany StreamInsight does not support the SelectMany operator in its usual form (which is analogous to SQL’s “CROSS APPLY” operator): static IEnumerable<R> SelectMany<T, R>(this IEnumerable<T> source, Func<T, IEnumerable<R>> collectionSelector) It instead uses SelectMany as a convenient syntactic representation of an inner join. The parameter to the selector function is thus unavailable. Because the parameter isn’t supported, its type in StreamInsight 1.0 – 2.0 wasn’t carefully scrutinized. Unfortunately, the type chosen for the parameter is nonsensical to LINQ programmers: static CepStream<R> SelectMany<T, R>(this CepStream<T> source, Expression<Func<CepStream<T>, CepStream<R>>> streamSelector) Using Unit as the type for the parameter accurately reflects the StreamInsight’s capabilities: static IQStreamable<R> SelectMany<T, R>(this IQStreamable<T> source, Expression<Func<Unit, IQStreamable<R>>> streamSelector) For queries that succeed – that is, queries that do not reference the stream selector parameter – there is no difference between the code written for the two overloads: from x in xs from y in ys select f(x, y) Top-K The Take operator used in StreamInsight causes confusion for LINQ programmers because it is applied to the (unbounded) stream rather than the (bounded) window, suggesting that the query as a whole will return k rows: (from win in xs.SnapshotWindow() from x in win orderby x.A select x.B).Take(k) The use of SelectMany is also unfortunate in this context because it implies the availability of the window parameter within the remainder of the comprehension. The following compiles but fails at runtime: (from win in xs.SnapshotWindow() from x in win orderby x.A select win).Take(k) The Take operator in 2.1 is applied to the window rather than the stream: Before After (from win in xs.SnapshotWindow() from x in win orderby x.A select x.B).Take(k) from win in xs.SnapshotWindow() from b in     (from x in win     orderby x.A     select x.B).Take(k) select b Multicast We are introducing an explicit multicast operator in order to preserve expression identity, which is important given the semantics about moving code to and from StreamInsight. This also better matches existing LINQ dialects, such as Reactive. This pattern enables expressing multicasting in two ways: Implicit Explicit var ys = from x in xs          where x.A > 1          select x; var zs = from y1 in ys          from y2 in ys.ShiftEventTime(_ => TimeSpan.FromSeconds(1))          select y1 + y2; var ys = from x in xs          where x.A > 1          select x; var zs = ys.Multicast(ys1 =>     from y1 in ys1     from y2 in ys1.ShiftEventTime(_ => TimeSpan.FromSeconds(1))     select y1 + y2; Notice the product translates an expression using implicit multicast into an expression using the explicit multicast operator. The user does not see this translation. Default window policies Only default window policies are supported in the new surface. Other policies can be simulated by using AlterEventLifetime. Before After xs.SnapshotWindow(     WindowInputPolicy.ClipToWindow,     SnapshotWindowInputPolicy.Clip) xs.SnapshotWindow() xs.TumblingWindow(     TimeSpan.FromSeconds(1),     HoppingWindowOutputPolicy.PointAlignToWindowEnd) xs.TumblingWindow(     TimeSpan.FromSeconds(1)) xs.TumblingWindow(     TimeSpan.FromSeconds(1),     HoppingWindowOutputPolicy.ClipToWindowEnd) Not supported … LeftAntiJoin Representation of LASJ as a correlated sub-query in the LINQ surface is problematic as the StreamInsight engine does not support correlated sub-queries (see discussion of SelectMany). The current syntax requires the introduction of an otherwise unsupported ‘IsEmpty()’ operator. As a result, the pattern is not discoverable and implies capabilities not present in the server. The direct representation of LASJ is used instead: Before After from x in xs where     (from y in ys     where x.A > y.B     select y).IsEmpty() select x xs.LeftAntiJoin(ys, (x, y) => x.A > y.B) from x in xs where     (from y in ys     where x.A == y.B     select y).IsEmpty() select x xs.LeftAntiJoin(ys, x => x.A, y => y.B) ApplyWithUnion The ApplyWithUnion methods have been deprecated since their signatures are redundant given the standard SelectMany overloads: Before After xs.GroupBy(x => x.A).ApplyWithUnion(gs => from win in gs.SnapshotWindow() select win.Count()) xs.GroupBy(x => x.A).SelectMany(     gs =>     from win in gs.SnapshotWindow()     select win.Count()) xs.GroupBy(x => x.A).ApplyWithUnion(gs => from win in gs.SnapshotWindow() select win.Count(), r => new { r.Key, Count = r.Payload }) from x in xs group x by x.A into gs from win in gs.SnapshotWindow() select new { gs.Key, Count = win.Count() } Alternate UDO syntax The representation of UDOs in the StreamInsight LINQ dialect confuses cardinalities. Based on the semantics of user-defined operators in StreamInsight, one would expect to construct queries in the following form: from win in xs.SnapshotWindow() from y in MyUdo(win) select y Instead, the UDO proxy method is referenced within a projection, and the (many) results returned by the user code are automatically flattened into a stream: from win in xs.SnapshotWindow() select MyUdo(win) The “many-or-one” confusion is exemplified by the following example that compiles but fails at runtime: from win in xs.SnapshotWindow() select MyUdo(win) + win.Count() The above query must fail because the UDO is in fact returning many values per window while the count aggregate is returning one. Original syntax New alternate syntax from win in xs.SnapshotWindow() select win.UdoProxy(1) from win in xs.SnapshotWindow() from y in win.UserDefinedOperator(() => new Udo(1)) select y -or- from win in xs.SnapshotWindow() from y in win.UdoMacro(1) select y Notice that this formulation also sidesteps the dynamic type pitfalls of the existing “proxy method” approach to UDOs, in which the type of the UDO implementation (TInput, TOuput) and the type of its constructor arguments (TConfig) need to align in a precise and non-obvious way with the argument and return types for the corresponding proxy method. UDSO syntax UDSO currently leverages the DataContractSerializer to clone initial state for logical instances of the user operator. Initial state will instead be described by an expression in the new LINQ surface. Before After xs.Scan(new Udso()) xs.Scan(() => new Udso()) Name changes ShiftEventTime => AlterEventStartTime: The alter event lifetime overload taking a new start time value has been renamed. CountByStartTimeWindow => CountWindow

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  • Lightweight, dynamic, fully JavaScript web UI library recommendations

    - by Matt Greer
    I am looking for recommendations for a lightweight, dynamic, fully JavaScript UI library for websites. Doesn't have to be amazing visually, the end result is for simple demos I create. What I want can be summed up as "Ext-like, but not GPL'ed, and a much smaller footprint". I want to be able to construct UIs dynamically and fully through code. My need for this is currently driven by this particle designer. Depending on what query parameters you give it, the UI components change, example 1, example2. Currently this is written in Ext, but Ext's license and footprint are turn offs for me. I like UKI a lot, but it's not very good for dynamically building UIs since everything is absolutely positioned. Extending Uki to support that is something I am considering. Ideally the library would let me make UIs with a pattern along the lines of: var container = new SomeUI.Container(); container.add(new SomeUI.Label('Color Components')); container.add(new SomeUI.NumberField('R')); container.add(new SomeUI.NumberField('G')); container.add(new SomeUI.NumberField('B')); container.add(new SomeUI.CheckBox('Enable Alpha')); container.renderTo(someDiv);

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  • Are copyright notices really required?

    - by Alasdair
    Ever since I made my first web page 13 years ago I have followed the pattern of showing a copyright notice in the footer of each page. Over the years the format of this notice has changed in the following way; Copyright © <NAME> yyyy. All rights are reserved. Copyright © <NAME> yyyy © yyyy <NAME> © <NAME> This has generally mirrored the format used by Google. However, I recently noticed that they no longer display a copyright notice on their home page nor have one in their source code/meta tags. I see they still display it on most (if not all) other pages. I understand that Google are very keen to keep the word count down on their homepage, which could be the reason for this sacrafice, but my question is more general and relates to all websites. Since I've always just done it out of habit, I'm hoping someone can explain if/when I a copyright notice is actually required to protect your content and rights. Also, when it is required, is there a format in which the notice must adhere to in order to be valid?

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  • Is it customary to write Java domain objects / data transfer objects with public member variables on mobile platforms?

    - by Sean Mickey
    We performed a code review recently of mobile application Java code that was developed by an outside contractor and noticed that all of the domain objects / data transfer objects are written in this style: public class Category { public String name; public int id; public String description; public int parentId; } public class EmergencyContact { public long id; public RelationshipType relationshipType; public String medicalProviderType; public Contact contact; public String otherPhone; public String notes; public PersonName personName; } Of course, these members are then accessed directly everywhere else in the code. When we asked about this, the developers told us that this is a customary performance enhancement design pattern that is used on mobile platforms, because mobile devices are resource-limited environments. It doesn't seem to make sense; accessing private members via public getters/setters doesn't seem like it could add much overhead. And the added benefits of encapsulation seem to outweigh the benefits of this coding style. Is this generally true? Is this something that is normally done on mobile platforms for the reasons given above? All feedback welcome and appreciated -

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  • Star Trek inspired home automation visualisation

    - by Zak McKracken
    I’ve always been a more or less active fan of Star Trek. During the construction phase of my house I started coding a GUI for controlling the house which has an EIB. Just for fun I designed a version inspired by the LCARS design used in Star Trek TNG and showed this to my wife. I showed her several designs before but this was the only one, she really liked. So I decided to go on with this. I started a C# WinForms application. The software runs on a wall mounted Shuttle Barebone-PC. First plan was an industrial panel-pc but the processor was too slow. The now-used Atom is ok. I started with the LCARS-controls found on Codeproject. Since the classic LCARS design divides the screen into two parts this tended to be impracticable, so I used my own design For now the software is able to: Switch lights/wall outlets Show current temperatures for all room controllers Show outside temperature with a 24h trend chart Show the status of the two heat pumps Provide an alarm clock (e.g. for cooking) Play internet radio streams Control absence Mute the door bell Speak status messages via speech synthesis For now, I’m working on an integration of my electric meter. The main heat pump and the electric meter are connected to my LAN. I also tried some speech recognition, but I’ve problems with the microphone. I't’s working when you are right in front of the PC, but not far away, let’s say on the other side of the room. So this is the main view. The table displays raw values which are sent over the EIB – completely useless but looks great For each floor I have a different view. Here you can see the temperatures and check the status of the lights (the buttons are blinking when a light is switched on) This is the view for the heat pump:   Next step would be to integrate a control of my squeezebox server (I use different Squeezeboxes through the house as a multiroom audio solution)

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  • Tracking state of a one time event on a big website

    - by Mattis
    Assume a website with 250 million active users. I add a new feature to the website. Once a user visits I want to use a short tutorial to teach them how to use said feature. I only want them to complete the tutorial once (or actively click it away). What is the smart way to code the verification check for this? How do I track the progress in the database? Having a separate table with like NewTutorial_completed = 1 for user_id = 21312315 would just snowball. It also feels intuitively bad to check for every one-time event for every user on every page view. While writing the question I got one idea, to have a separate event log that is checked periodically for any new action the user need to see or perform. I push events to this log and once they are completed they are removed from the log. No need to store NewTutorial_completed = 1-type variables this way. I am sure this is a common problem. I would appreciate any input on what best practice is.

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  • The requested resource is not available

    - by James Pj
    I have written a Java servlet program and run it through local Tomcat 7, But it was showing following error : HTTP Status 404 - /skypark/registration type Status report message /skypark/registration description The requested resource is not available. Apache Tomcat/7.0.33 I don't know what was the reason for it my Html page is <html> <head> <title> User registration </title> </head> <body> <form action="registration" method="post"> <center> <h2><b>Skypark User Registration</b></h2> <table border="0"> <tr><td> First Name </td><td> <input type="text" name="fname"/></br> </td></tr><tr><td> Last Name </td><td> <input type="text" name="lname"/></br> </td></tr><tr><td> UserName </td><td> <input type="text" name="uname"></br> </td></tr><tr><td> Enter Password </td><td> <input type="password" name="pass"></br> </td></tr><tr><td> Re-Type Password </td><td> <input type="password" name="pass1"></br> </td></tr><tr><td> Enter Email ID </td><td> <input type="email" name="email1"></br> </td></tr><tr><td> Phone Number </td><td> <input type="number" name="phone"> </td></tr><tr><td> Gender<br> </td></tr><tr><td> <input type="radio" name="gender" value="Male">Male</input></br> </td></tr><tr><td> <input type="radio" name="gender" value="Female">Female</input></br> </td></tr><tr><td> Enter Your Date of Birth<br> </td><td> <Table Border=0> <tr> <td> Date </td> <td>Month</td> <td>Year</td> </tr><tr> <td> <select name="date"> <option value="1">1</option> <option value="2">2</option> <option value="3">3</option> <option value="4">4</option> <option value="5">5</option> . . . have some code . . . </table> <input type="submit" value="Submit"></br> </center> </form> </body> </html> My servlet is : package skypark; import skypark.*; import java.io.*; import javax.servlet.*; import javax.servlet.http.*; import java.sql.*; public class Registration extends HttpServlet { public static Connection prepareConnection()throws ClassNotFoundException,SQLException { String dcn="oracle.jdbc.driver.OracleDriver"; String url="jdbc:oracle:thin:@JamesPJ-PC:1521:skypark"; String usname="system"; String pass="tiger"; Class.forName(dcn); return DriverManager.getConnection(url,usname,pass); } public void doPost(HttpServletRequest req,HttpServletResponse resp)throws ServletException,IOException { resp.setContentType("text/html"); PrintWriter out=resp.getWriter(); try { String phone1,uname,fname,lname,dob,address,city,state,country,pin,email,password,gender,lang,qual,relegion,privacy,hobbies,fav; uname=req.getParameter("uname"); fname=req.getParameter("fname"); lname=req.getParameter("lname"); dob=req.getParameter("date"); address=req.getParameter("address"); city=req.getParameter("city"); state=req.getParameter("state"); country=req.getParameter("country"); pin=req.getParameter("pin"); email=req.getParameter("email1"); password=req.getParameter("password"); gender=req.getParameter("gender"); phone1=req.getParameter("phone"); lang=""; qual=""; relegion=""; privacy=""; hobbies=""; fav=""; int phone=Integer.parseInt(phone1); Connection con=prepareConnection(); String Query="Insert into regdetails values(?,?,?,?,?,?,?,?,?,?,?,?,?,?,?,?)"; PreparedStatement ps=con.prepareStatement(Query); ps.setString(1,uname); ps.setString(2,fname); ps.setString(3,lname); ps.setString(4,dob); ps.setString(5,address); ps.setString(6,city); ps.setString(7,state); ps.setString(8,country); ps.setString(9,pin); ps.setString(10,lang); ps.setString(11,qual); ps.setString(12,relegion); ps.setString(13,privacy); ps.setString(14,hobbies); ps.setString(15,fav); ps.setString(16,gender); int c=ps.executeUpdate(); String query="insert into passmanager values(?,?,?,?)"; PreparedStatement ps1=con.prepareStatement(query); ps1.setString(1,uname); ps1.setString(2,password); ps1.setString(3,email); ps1.setInt(4,phone); int i=ps1.executeUpdate(); if(c==1||c==Statement.SUCCESS_NO_INFO && i==1||i==Statement.SUCCESS_NO_INFO) { out.println("<html><head><title>Login</title></head><body>"); out.println("<center><h2>Skypark.com</h2>"); out.println("<table border=0><tr>"); out.println("<td>UserName/E-Mail</td>"); out.println("<form action=login method=post"); out.println("<td><input type=text name=uname></td>"); out.println("</tr><tr><td>Password</td>"); out.println("<td><input type=password name=pass></td></tr></table>"); out.println("<input type=submit value=Login>"); out.println("</form></body></html>"); } else { out.println("<html><head><title>Error!</title></head><body>"); out.println("<center><b>Given details are incorrect</b>"); out.println(" Please try again</center></body></html>"); RequestDispatcher rd=req.getRequestDispatcher("registration.html"); rd.include(req,resp); return; } } catch(Exception e) { out.println("<html><head><title>Error!</title><body>"); out.println("<b><i>Unable to process try after some time</i></b>"); out.println("</body></html>"); RequestDispatcher rd=req.getRequestDispatcher("registration.html"); rd.include(req,resp); return; } out.flush(); out.close(); } } And the web.xml file is <?xml version="1.0" encoding="UTF-8"?> <web-app xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0" metadata-complete="true"> <servlet> <servlet-name>reg</servlet-name> <servlet-class>skypark.Registration</servlet-class> </servlet> <servlet-mapping> <servlet-name>reg</servlet-name> <url-pattern>/registration</url-pattern> </servlet-mapping> This i kept in C:\Program Files\Apache Software Foundation\Tomcat 7.0\webapps\skypark\WEB_INF\web.xml and servlet class in C:\Program Files\Apache Software Foundation\Tomcat 7.0\webapps\skypark\WEB_INF\classes\skypark and registration.html in C:\Program Files\Apache Software Foundation\Tomcat 7.0\webapps\skypark\ if any mistake in this makes above error means please help me.Thanks in advance....

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