Search Results

Search found 46053 results on 1843 pages for 'thinly veiled question mark'.

Page 436/1843 | < Previous Page | 432 433 434 435 436 437 438 439 440 441 442 443  | Next Page >

  • Can Google Employees See My Saved Google Chrome Passwords?

    - by Jason Fitzpatrick
    Storing your passwords in your web browser seems like a great time saver, but are the passwords secure and inaccessible to others (even employees of the browser company) when squirreled away? Today’s Question & Answer session comes to us courtesy of SuperUser—a subdivision of Stack Exchange, a community-driven grouping of Q&A web sites. The Question SuperUser reader MMA is curious if Google employees have (or could have) access to the passwords he stores in Google Chrome: I understand that we are really tempted to save our passwords in Google Chrome. The likely benefit is two fold, You don’t need to (memorize and) input those long and cryptic passwords. These are available wherever you are once you log in to your Google account. The last point sparked my doubt. Since the password is available anywhere, the storage must in some central location, and this should be at Google. Now, my simple question is, can a Google employee see my passwords? Searching over the Internet revealed several articles/messages. Do you save passwords in Chrome? Maybe you should reconsider: Talks about your passwords being stolen by someone who has access to your computer account. Nothing mentioned about the central storage security and vulnerability. There is even a response from Chrome browser security tech lead about the first issue. Chrome’s insane password security strategy: Mostly along the same line. You can steal password from somebody if you have access to the computer account. How to Steal Passwords Saved in Google Chrome in 5 Simple Steps: Teaches you how to actually perform the act mentioned in the previous two when you have access to somebody else’s account. There are many more (including this one at this site), mostly along the same line, points, counter-points, huge debates. I refrain from mentioning them here, simply carry a search if you want to find them. Coming back to my original query, can a Google employee see my password? Since I can view the password using a simple button, definitely they can be unhashed (decrypted) even if encrypted. This is very different from the passwords saved in Unix-like OS’s where the saved password can never be seen in plain text. They use a one-way encryption algorithm to encrypt your passwords. This encrypted password is then stored in the passwd or shadow file. When you attempt to login, the password you type in is encrypted again and compared with the entry in the file that stores your passwords. If they match, it must be the same password, and you are allowed access. Thus, a superuser can change my password, can block my account, but he can never see my password. So are his concerns well founded or will a little insight dispel his worry? The Answer SuperUser contributor Zeel helps put his mind at ease: Short answer: No* Passwords stored on your local machine can be decrypted by Chrome, as long as your OS user account is logged in. And then you can view those in plain text. At first this seems horrible, but how did you think auto-fill worked? When that password field gets filled in, Chrome must insert the real password into the HTML form element – or else the page wouldn’t work right, and you could not submit the form. And if the connection to the website is not over HTTPS, the plain text is then sent over the internet. In other words, if chrome can’t get the plain text passwords, then they are totally useless. A one way hash is no good, because we need to use them. Now the passwords are in fact encrypted, the only way to get them back to plain text is to have the decryption key. That key is your Google password, or a secondary key you can set up. When you sign into Chrome and sync the Google servers will transmit the encrypted passwords, settings, bookmarks, auto-fill, etc, to your local machine. Here Chrome will decrypt the information and be able to use it. On Google’s end all that info is stored in its encrpyted state, and they do not have the key to decrypt it. Your account password is checked against a hash to log in to Google, and even if you let chrome remember it, that encrypted version is hidden in the same bundle as the other passwords, impossible to access. So an employee could probably grab a dump of the encrypted data, but it wouldn’t do them any good, since they would have no way to use it.* So no, Google employees can not** access your passwords, since they are encrypted on their servers. * However, do not forget that any system that can be accessed by an authorized user can be accessed by an unauthorized user. Some systems are easier to break than other, but none are fail-proof. . . That being said, I think I will trust Google and the millions they spend on security systems, over any other password storage solution. And heck, I’m a wimpy nerd, it would be easier to beat the passwords out of me than break Google’s encryption. ** I am also assuming that there isn’t a person who just happens to work for Google gaining access to your local machine. In that case you are screwed, but employment at Google isn’t actually a factor any more. Moral: Hit Win + L before leaving machine. While we agree with zeel that it’s a pretty safe bet (as long as your computer is not compromised) that your passwords are in fact safe while stored in Chrome, we prefer to encrypt all our logins and passwords in a LastPass vault. Have something to add to the explanation? Sound off in the the comments. Want to read more answers from other tech-savvy Stack Exchange users? Check out the full discussion thread here.     

    Read the article

  • Issues with touch buttons in XNA (Release state to be precise)

    - by Aditya
    I am trying to make touch buttons in WP8 with all the states (Pressed, Released, Moved), but the TouchLocationState.Released is not working. Here's my code: Class variables: bool touching = false; int touchID; Button tempButton; Button is a separate class with a method to switch states when touched. The Update method contains the following code: TouchCollection touchCollection = TouchPanel.GetState(); if (!touching && touchCollection.Count > 0) { touching = true; foreach (TouchLocation location in touchCollection) { for (int i = 0; i < menuButtons.Count; i++) { touchID = location.Id; // store the ID of current touch Point touchLocation = new Point((int)location.Position.X, (int)location.Position.Y); // create a point Button button = menuButtons[i]; if (GetMenuEntryHitBounds(button).Contains(touchLocation)) // a method which returns a rectangle. { button.SwitchState(true); // change the button state tempButton = button; // store the pressed button for accessing later } } } } else if (touchCollection.Count == 0) // clears the state of all buttons if no touch is detected { touching = false; for (int i = 0; i < menuButtons.Count; i++) { Button button = menuButtons[i]; button.SwitchState(false); } } menuButtons is a list of buttons on the menu. A separate loop (within the Update method) after the touched variable is true if (touching) { TouchLocation location; TouchLocation prevLocation; if (touchCollection.FindById(touchID, out location)) { if (location.TryGetPreviousLocation(out prevLocation)) { Point point = new Point((int)location.Position.X, (int)location.Position.Y); if (prevLocation.State == TouchLocationState.Pressed && location.State == TouchLocationState.Released) { if (GetMenuEntryHitBounds(tempButton).Contains(point)) // Execute the button action. I removed the excess } } } } The code for switching the button state is working fine but the code where I want to trigger the action is not. location.State == TouchLocationState.Released mostly ends up being false. (Even after I release the touch, it has a value of TouchLocationState.Moved) And what is more irritating is that it sometimes works! I am really confused and stuck for days now. Is this the right way? If yes then where am I going wrong? Or is there some other more effective way to do this? PS: I also posted this question on stack overflow then realized this question is more appropriate in gamedev. Sorry if it counts as being redundant.

    Read the article

  • CRM vs VRM

    - by David Dorf
    In a previous post, I discussed the potential power of combining social, interest, and location graphs in order to personalize marketing and shopping experiences for consumers.  Marketing companies have been trying to collect detailed information for that very purpose, a large majority of which comes from tracking people on the internet.  But their approaches stem from the one-way nature of traditional advertising.  With TV, radio, and magazines there is no opportunity to truly connect to customers, which has trained marketing companies to [covertly] collect data and segment customers into easily identifiable groups.  To a large extent, we think of this as CRM. But what if we turned this viewpoint upside-down to accommodate for the two-way nature of social media?  The notion of marketing as conversations was the basis for the Cluetrain, an early attempt at drawing attention to the fact that customers are actually unique humans.  A more practical implementation is Project VRM, which is a reverse CRM of sorts.  Instead of vendors managing their relationships with customers, customers manage their relationships with vendors. Your shopping experience is not really controlled by you; rather, its controlled by the retailer and advertisers.  And unfortunately, they typically don't give you a say in the matter.  Yes, they might tailor the content for "female age 25-35 interested in shoes" but that's not really the essence of you, is it?  A better approach is to the let consumers volunteer information about themselves.  And why wouldn't they if it means a better, more relevant shopping experience?  I'd gladly list out my likes and dislikes in exchange for getting rid of all those annoying cookies on my harddrive. I really like this diagram from Beyond SocialCRM as it captures the differences between CRM and VRM. The closest thing to VRM I can find is Buyosphere, a start-up that allows consumers to track their shopping history across many vendors, then share it appropriately.  Also, Amazon does a pretty good job allowing its customers to edit their profile, which includes everything you've ever purchased from Amazon.  You can mark items as gifts, or explicitly exclude them from their recommendation engine.  This is a win-win for both the consumer and retailer. So here is my plea to retailers: Instead of trying to infer my interests from snapshots of my day, please just ask me.  We'll both have a better experience in the long-run.

    Read the article

  • Linux kernel regression on power usage

    - by dago
    Webupd8 reported this power management fix for the 2.6.38 Linux kernel regression: Add the following to the boot grub line "pcie_aspm=force" My question - how does this suggested fix differ from this hint from powertop: Suggestion: Enable Device Power Management by pressing the P key, which execute the following action: find /sys/devices/pci* -path "*power/control" -exec bash -c "echo auto > '{}'" \;

    Read the article

  • Why wearing Jeans is considered unprofessional?

    - by Gopinath
    When I started my career 9 years ago I use to wear casual wear to office – Jeans & T-Shirts all the 5 days. The environment at workplace during those days encouraged me to be casual and many of my colleagues use to come in Jeans. We just started our career those days it was perfectly fine to be in casual. As I grow up in the ladder, I started feeling the discomfort of wearing Jeans at work. During clients visits, senior managers meetings and consultations I was an odd man in the crowd as the rest of them are in formals. In order to be one among the professionals I’m forced change my dressing style and start wearing formals. But  the question of “Why wearing jeans to workplace is considered as unprofessional?” use in linger in my mind till today. I got the answer to my question from a discussion thread on Quora When they were invented, jeans were associated with blue-collar work. They were meant to get muddy and gross and take lots of abuse without falling apart, even if you wore the same pair every day. The people who bought them were the ones whose lives required durable clothing. And another commenter says… A professional image is critical to cementing business relationships, and part of that is, for right or wrong, how you dress. Jeans are typically associated with "kicking back", relaxation, leisure, informality,  and even a slightly rebellious flavor. The style and condition of the jeans are a consideration, as we often wear jeans into advanced states of being worn down, with tearing, etc.. that we generally do not do with other clothing items. I agree with this theory even though it may be centuries old. If you want to look like a professional and treated like a professional it’s better to be dress up in formals. These days I make a point to be in formals at workplace. Not everyone is Steve Jobs to wear a Jean & Turtle Neck T-shirt  right? CC Image credit flickr/exey

    Read the article

  • The Written Roles of Chief Technology Officer

    - by Jon Hopkins
    A follow up to this question: The Written Roles of Software Development Manager What is the role and what are the responsibilities of a CTO when it's done well, with particular reference to how it might pertain to a programmer with aspirations towards this sort of position? (Reason for asking - it's one potential career destination for programmers looking to move away from a purely hands-on role and for those with this sort of ambition it's worth knowing what it actually entails).

    Read the article

  • Is the timeago date format appropiate for a website?

    - by Eduardo Campañó
    We're building a website for a startup and we encourage using the "timeago" format for displaying dates (i.e. less than a minute ago, about 5 minutes ago, about a month ago, etc.) but the client argues that it's not used in the US, that people are just not used to it. I can make a list of hundreds of sites using it, but of course, I'm a geek. So in adition to the main question, what are the pros and cons of the "timeago" date format?

    Read the article

  • Where should I redirect (removed) phishing pages

    - by tinjaw
    I was unfortunately the victim of a PHP exploit. Looking through my webserver logs, people are still attempting to reach the URL used in the phish. I want to redirect them to a site that will educate these people on what phishing is. My question: Is there a (generic / vendor-neutral) phishing education website that you suggest I send them to with a 301 redirect? (I assume a 301 is the best option.)

    Read the article

  • Why I Love Microsoft Development

    - by Brian Lanham
    I've been writing software for a while and recently had an opportunity to broaden my horizons and start developing for iOS. We decided to leverage, as much as possible, our existing skills and use MonoTouch and MonoDevelop by Novell.    For those of you who do not know, Mono is a .NET port originally designed for Linux but adapted for other platforms as well. MonoTouch is a port specifically for building iOS applications using the .NET framework. MonoDroid is a port (in CTP-esque release) for Android.   A MISSING COMPONENT - VISUAL DESIGNER   MonoDevelop lacks one very significant component compared with other tools I am using: NO VISUAL DESIGNER. Instead of using an integrated visual designer, MonoDevelop shells to the Mac OS "Interface Builder".  Since MonoDevelop lets me have a "Visual Studio-esque" feel *and* I get to use C#, AND it's FREE, I am gladly willing to overlook this.  In fact, it's not even a question.  Free?  Sure, I'll take it with no Visual Designer.   In my experiences I've grown from UNIX and DOS to .NET development through many steps. Java/JSP/Servlets; Windows; Web; etc. I've been doing .NET for quite a few years and I guess I just got "comfortable" with the tools.   WHY AM I NOT GETTING IT?   Interface Builder (IB) is amazingly confusing for me. I had the opportunity to speak at the Northern VA Code Camp on 12/11/2010. My presentation was "Getting Started with iOS Development using MonoTouch and C#".    At the visual design part of the presentation, I asked one of the 3 or 4 Mac developers in the room about my confusion with the IB. I don't understand why the "Classes" list includes objects. I don't understand what "File's Owner" is. And, most importantly, WHAT THE HECK IS AN OUTLET AND WHY IS IT NECESSARY?!?!?"   His response to these question (especially Outlets): "They did it wrong."   I'm accustom to a visual designer that creates variables for graphical widgets for me. Not IB. Instead, I have to create "Outlets" manually. I still do not understand why and, the explanation from a seasoned Mac developer is that it's wrong. (He received nods of confirmation from the other Mac devs in the room.)   I LOVE MS DEV   I love development for Microsoft platforms using Microsoft development tools. I love Windows 7. I love Visual Studio 2010. I love SQL Server. Azure, Entity Framework, Active Directory, Office, WCF/WF/WPF, etc. are all designed with integration in mind. They are also all designed with developers in mind.   Steve Ballmer recently ranted "It's the developers!" That's why it is relatively quick to build apps using MS tools. Clearly, MS knows that while we usually enjoy building technology solutions, we are here to make money. And we need tools that accelerate our time to market without compromising the power and quality of our solutions.   So, yeah, I am sucking up I guess. But I love Microsoft Development. Thank you, Microsoft, for providing the plethora of great development tools.    P.S. (but please slow down a bit…I'm having trouble keeping up!)

    Read the article

  • Ideal programming language learning sequence?

    - by Gulshan
    What do you think? What is the ideal programming language learning sequence which will cover most of the heavily used languages and paradigms today as well as help to grasp common programming basics, ideas and practices? You can even suggest learning sequence for paradigms rather than languages. N.B. : This is port of the question I asked in stackoverflow and was closed for being subjective and argumentative.

    Read the article

  • Microsoft Wireless Keyboard 3000 v2.0 doesnt recognize "Flip Key"

    - by Michael Clare
    The Microsoft Wireless Keyboard 3000 v2.0 has a new key called a "flip key" where the right windows button should be (to the right of the right alt key). This is a picture, the key in question is called "Windows Flip": http://www.microsoft.com/hardware/en-us/p/digital-media-keyboard-3000#details I am using Ubuntu 11.10 and this key is not recognized at all by the system: I have run "sudo showkey" with no results. Any help would be greatly appreciated, I would like to map this to be a Right-Super key as it should be.

    Read the article

  • SQL SERVER – DELETE, TRUNCATE and RESEED Identity

    - by pinaldave
    Yesterday I had a headache answering questions to one of the DBA on the subject of Reseting Identity Values for All Tables. After talking to the DBA I realized that he has no clue about how the identity column behaves when there is DELETE, TRUNCATE or RESEED Identity is used. Let us run a small T-SQL Script. Create a temp table with Identity column beginning with value 11. The seed value is 11. USE [TempDB] GO -- Create Table CREATE TABLE [dbo].[TestTable]( [ID] [int] IDENTITY(11,1) NOT NULL, [var] [nchar](10) NULL ) ON [PRIMARY] GO -- Build sample data INSERT INTO [TestTable] VALUES ('val') GO When seed value is 11 the next value which is inserted has the identity column value as 11. – Select Data SELECT * FROM [TestTable] GO Effect of DELETE statement -- Delete Data DELETE FROM [TestTable] GO When the DELETE statement is executed without WHERE clause it will delete all the rows. However, when a new record is inserted the identity value is increased from 11 to 12. It does not reset but keep on increasing. -- Build sample data INSERT INTO [TestTable] VALUES ('val') GO -- Select Data SELECT * FROM [TestTable] Effect of TRUNCATE statement -- Truncate table TRUNCATE TABLE [TestTable] GO When the TRUNCATE statement is executed it will remove all the rows. However, when a new record is inserted the identity value is increased from 11 (which is original value). TRUNCATE resets the identity value to the original seed value of the table. -- Build sample data INSERT INTO [TestTable] VALUES ('val') GO -- Select Data SELECT * FROM [TestTable] GO Effect of RESEED statement If you notice I am using the reseed value as 1. The original seed value when I created table is 11. However, I am reseeding it with value 1. -- Reseed DBCC CHECKIDENT ('TestTable', RESEED, 1) GO When we insert the one more value and check the value it will generate the new value as 2. This new value logic is Reseed Value + Interval Value – in this case it will be 1+1 = 2. -- Build sample data INSERT INTO [TestTable] VALUES ('val') GO -- Select Data SELECT * FROM [TestTable] GO Here is the clean up act. -- Clean up DROP TABLE [TestTable] GO Question for you: If I reseed value with some random number followed by the truncate command on the table what will be the seed value of the table. (Example, if original seed value is 11 and I reseed the value to 1. If I follow up with truncate table what will be the seed value now? Here is the complete script together. You can modify it and find the answer to the above question. Please leave a comment with your answer. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

    Read the article

  • Why Use !boolean_variable Over boolean_variable == false

    - by ell
    A comment on this question: Calling A Method that returns a boolean value inside a conditional statement says that you should use !boolean instead of boolean == false when testing conditions. Why? To me boolean == false is much more natural in English and is more explicit. I apologise if this is just a matter of style, but I was wondering if there was some other reason for this preference of !boolean?

    Read the article

  • Using lookahead assertions in regular expressions

    - by Greg Jackson
    I use regular expressions on a daily basis, as my daily work is 90% in Perl (legacy codebase, but that's a different issue). Despite this, I still find lookahead and lookbehind to be terribly confusing and often unreadable. Right now, if I were to get a code review with a lookahead or lookbehind, I would immediately send it back to see if the problem can be solved by using multiple regular expressions or a different approach. The following are the main reasons I tend not to like them: They can be terribly unreadable. Lookahead assertions, for example, start from the beginning of the string no matter where they are placed. That, among other things, can cause some very "interesting" and non-obvious behaviors. It used to be the case that many languages didn't support lookahead/lookbehind (or supported them as "experimental features"). This isn't the case quite as much, but there's still always the question as to how well it's supported. Quite frankly, they feel like a dirty hack. Regexps often already are, but they can also be quite elegant, and have gained widespread acceptance. I've gotten by without any need for them at all... sometimes I think that they're extraneous. Now, I'll freely admit that especially the last two reasons aren't really good ones, but I felt that I should enumerate what goes through my mind when I see one. I'm more than willing to change my mind about them, but I feel that they violate some of my core tenets of programming, including: Code should be as readable as possible without sacrificing functionality -- this may include doing something in a less efficient, but clearer was as long as the difference is negligible or unimportant to the application as a whole. Code should be maintainable -- if another programmer comes along to fix my code, non-obvious behavior can hide bugs or make functional code appear buggy (see readability) "The right tool for the right job" -- I'm sure you can come up with contrived examples that could use lookahead, but I've never come across something that really needs them in my real-world development work. Is there anything that they're really the best tool for, as opposed to, say, multiple regexps (or, alternatively, are they the best tool for most cases they're used for today). My question is this: Is it good practice to use lookahead/lookbehind in regular expressions, or are they simply a hack that have found their way into modern production code? I'd be perfectly happy to be convinced that I'm wrong about this, and simple examples are useful for examples or illustration, but by themselves, won't be enough to convince me.

    Read the article

  • How can I set the date format to my country setting?

    - by Jamina Meissner
    I am German, but I use only English software. Hence, I am also using English Ubuntu. It's not because I don't know how to install German Ubuntu. It's because I prefer to work with English software environment. However, I would like to keep date & time format in German format, just as I use a German keyboard layout in English Ubuntu. I can set the time format to 24h time. But how can I set the date format to German time format? It is irritating for me to have the day number before the time numbers: In other words, instead of "Oct 14 15:16" I want it to display "14 Okt" or (if only English language is available) "14 Oct 15:16" or "14th Oct 15:16". At least, the number of the day should be displayed before the month. In Windows, it was no problem to choose time/date/currency settings according to a chosen country. Where can I do this in Ubuntu? The best would be if I could freely enter the date/time format myself with variables (DD.MM hh.mm.ss etc). I found answers for Ubuntu 11.04, but not for Ubuntu 12.04. I am using Ubuntu 12.04, 64-bit. Keep in mind that I am a beginner. So I'd like to be able to do this via GUI, if possible. EDIT: I found the answer in a forum. Go to System Settings... and choose Language Support. There are two tabs, Language and Reginal Formats. You are by default on the Language tab. On the Language tab, click Install / Remove Languages. A window with a list of languages opens. Mark the language(s) you want to add for your time/date/currency format. Click Apply Changes. Ubuntu will now download and install the additional language files, as well as help files of other applications in this language. So don't be irritated. When Ubuntu has finished applying the changes, switch to Regional Formats tab. (Do not change the Language for menus and windows on the Language tab if you only want to change the date/time/unit format). There you can choose from the dropdown list the language for your preferred format for date/time/currency/unit. Log out and log in again to have the changes take effect.

    Read the article

  • Should UTF-16 be considered harmful?

    - by Artyom
    I'm going to ask what is probably quite a controversial question: "Should one of the most popular encodings, UTF-16, be considered harmful?" Why do I ask this question? How many programmers are aware of the fact that UTF-16 is actually a variable length encoding? By this I mean that there are code points that, represented as surrogate pairs, take more than one element. I know; lots of applications, frameworks and APIs use UTF-16, such as Java's String, C#'s String, Win32 APIs, Qt GUI libraries, the ICU Unicode library, etc. However, with all of that, there are lots of basic bugs in the processing of characters out of BMP (characters that should be encoded using two UTF-16 elements). For example, try to edit one of these characters: 𝄞 (U+1D11E) MUSICAL SYMBOL G CLEF 𝕥 (U+1D565) MATHEMATICAL DOUBLE-STRUCK SMALL T 𝟶 (U+1D7F6) MATHEMATICAL MONOSPACE DIGIT ZERO 𠂊 (U+2008A) Han Character You may miss some, depending on what fonts you have installed. These characters are all outside of the BMP (Basic Multilingual Plane). If you cannot see these characters, you can also try looking at them in the Unicode Character reference. For example, try to create file names in Windows that include these characters; try to delete these characters with a "backspace" to see how they behave in different applications that use UTF-16. I did some tests and the results are quite bad: Opera has problem with editing them (delete required 2 presses on backspace) Notepad can't deal with them correctly (delete required 2 presses on backspace) File names editing in Window dialogs in broken (delete required 2 presses on backspace) All QT3 applications can't deal with them - show two empty squares instead of one symbol. Python encodes such characters incorrectly when used directly u'X'!=unicode('X','utf-16') on some platforms when X in character outside of BMP. Python 2.5 unicodedata fails to get properties on such characters when python compiled with UTF-16 Unicode strings. StackOverflow seems to remove these characters from the text if edited directly in as Unicode characters (these characters are shown using HTML Unicode escapes). WinForms TextBox may generate invalid string when limited with MaxLength. It seems that such bugs are extremely easy to find in many applications that use UTF-16. So... Do you think that UTF-16 should be considered harmful?

    Read the article

  • How important is the choice of domain registrars? [closed]

    - by Harry Muscle
    We're consolidating all of our hosting providers onto one provider, however, this provider is strictly a hosting provider, they are not a domain registrar. The question I have is how important is the choice of registrars? Or in other words, if I point the domains to the hosting companies name servers, can the reliability of my registrar affect my websites in any way? If the registrar were to go down for a few days would that impact the accessibility of the websites? What would it impact? Thanks, Harry

    Read the article

  • Google doesn't always show rich snippets when the site uses structured data [duplicate]

    - by Sam Se
    This question is an exact duplicate of: Google Structured Data [on hold] 1 answer I'm so tired of the Google structured data recipe. After some days, it loses the image and the extra information. Then I test it again, and it shows again. Some other days in the future it might go away even if it is still showing in test tool. What i can do? I tried with RDFa and schema.org microdata.

    Read the article

  • How do I restrict concurrent statistics gathering to a small set of tables from a single schema?

    - by Maria Colgan
    I got an interesting question from one of my colleagues in the performance team last week about how to restrict a concurrent statistics gather to a small subset of tables from one schema, rather than the entire schema. I thought I would share the solution we came up with because it was rather elegant, and took advantage of concurrent statistics gathering, incremental statistics, and the not so well known “obj_filter_list” parameter in DBMS_STATS.GATHER_SCHEMA_STATS procedure. You should note that the solution outline below with “obj_filter_list” still applies, even when concurrent statistics gathering and/or incremental statistics gathering is disabled. The reason my colleague had asked the question in the first place was because he wanted to enable incremental statistics for 5 large partitioned tables in one schema. The first time you gather statistics after you enable incremental statistics on a table, you have to gather statistics for all of the existing partitions so that a synopsis may be created for them. If the partitioned table in question is large and contains a lot of partition, this could take a considerable amount of time. Since my colleague only had the Exadata environment at his disposal overnight, he wanted to re-gather statistics on 5 partition tables as quickly as possible to ensure that it all finished before morning. Prior to Oracle Database 11g Release 2, the only way to do this would have been to write a script with an individual DBMS_STATS.GATHER_TABLE_STATS command for each partition, in each of the 5 tables, as well as another one to gather global statistics on the table. Then, run each script in a separate session and manually manage how many of this session could run concurrently. Since each table has over one thousand partitions that would definitely be a daunting task and would most likely keep my colleague up all night! In Oracle Database 11g Release 2 we can take advantage of concurrent statistics gathering, which enables us to gather statistics on multiple tables in a schema (or database), and multiple (sub)partitions within a table concurrently. By using concurrent statistics gathering we no longer have to run individual statistics gathering commands for each partition. Oracle will automatically create a statistics gathering job for each partition, and one for the global statistics on each partitioned table. With the use of concurrent statistics, our script can now be simplified to just five DBMS_STATS.GATHER_TABLE_STATS commands, one for each table. This approach would work just fine but we really wanted to get this down to just one command. So how can we do that? You may be wondering why we didn’t just use the DBMS_STATS.GATHER_SCHEMA_STATS procedure with the OPTION parameter set to ‘GATHER STALE’. Unfortunately the statistics on the 5 partitioned tables were not stale and enabling incremental statistics does not mark the existing statistics stale. Plus how would we limit the schema statistics gather to just the 5 partitioned tables? So we went to ask one of the statistics developers if there was an alternative way. The developer told us the advantage of the “obj_filter_list” parameter in DBMS_STATS.GATHER_SCHEMA_STATS procedure. The “obj_filter_list” parameter allows you to specify a list of objects that you want to gather statistics on within a schema or database. The parameter takes a collection of type DBMS_STATS.OBJECTTAB. Each entry in the collection has 5 feilds; the schema name or the object owner, the object type (i.e., ‘TABLE’ or ‘INDEX’), object name, partition name, and subpartition name. You don't have to specify all five fields for each entry. Empty fields in an entry are treated as if it is a wildcard field (similar to ‘*’ character in LIKE predicates). Each entry corresponds to one set of filter conditions on the objects. If you have more than one entry, an object is qualified for statistics gathering as long as it satisfies the filter conditions in one entry. You first must create the collection of objects, and then gather statistics for the specified collection. It’s probably easier to explain this with an example. I’m using the SH sample schema but needed a couple of additional partitioned table tables to get recreate my colleagues scenario of 5 partitioned tables. So I created SALES2, SALES3, and COSTS2 as copies of the SALES and COSTS table respectively (setup.sql). I also deleted statistics on all of the tables in the SH schema beforehand to more easily demonstrate our approach. Step 0. Delete the statistics on the tables in the SH schema. Step 1. Enable concurrent statistics gathering. Remember, this has to be done at the global level. Step 2. Enable incremental statistics for the 5 partitioned tables. Step 3. Create the DBMS_STATS.OBJECTTAB and pass it to the DBMS_STATS.GATHER_SCHEMA_STATS command. Here, you will notice that we defined two variables of DBMS_STATS.OBJECTTAB type. The first, filter_lst, will be used to pass the list of tables we want to gather statistics on, and will be the value passed to the obj_filter_list parameter. The second, obj_lst, will be used to capture the list of tables that have had statistics gathered on them by this command, and will be the value passed to the objlist parameter. In Oracle Database 11g Release 2, you need to specify the objlist parameter in order to get the obj_filter_list parameter to work correctly due to bug 14539274. Will also needed to define the number of objects we would supply in the obj_filter_list. In our case we ere specifying 5 tables (filter_lst.extend(5)). Finally, we need to specify the owner name and object name for each of the objects in the list. Once the list definition is complete we can issue the DBMS_STATS.GATHER_SCHEMA_STATS command. Step 4. Confirm statistics were gathered on the 5 partitioned tables. Here are a couple of other things to keep in mind when specifying the entries for the  obj_filter_list parameter. If a field in the entry is empty, i.e., null, it means there is no condition on this field. In the above example , suppose you remove the statement Obj_filter_lst(1).ownname := ‘SH’; You will get the same result since when you have specified gather_schema_stats so there is no need to further specify ownname in the obj_filter_lst. All of the names in the entry are normalized, i.e., uppercased if they are not double quoted. So in the above example, it is OK to use Obj_filter_lst(1).objname := ‘sales’;. However if you have a table called ‘MyTab’ instead of ‘MYTAB’, then you need to specify Obj_filter_lst(1).objname := ‘”MyTab”’; As I said before, although we have illustrated the usage of the obj_filter_list parameter for partitioned tables, with concurrent and incremental statistics gathering turned on, the obj_filter_list parameter is generally applicable to any gather_database_stats, gather_dictionary_stats and gather_schema_stats command. You can get a copy of the script I used to generate this post here. +Maria Colgan

    Read the article

  • Ubuntu won't save my settings for thinkpad trackpoint

    - by serve.chilled
    I'm using Ubuntu 12.04 on a Thinkpad X200. To configure the trackpoint, I use "configure TrackPoint". Unfortunately I can't make Ubuntu saving my settings (concerning the sensitivity etc.). Whenever I reboot the computer, it's set to generic settings again. I already tried htorque's answer to a similar question and created a new udev-rule for the trackpoint-settings but it didn't helped. So, how can I make theses settings permanent?

    Read the article

  • Long polling using Spring MVC 3.2M1

    - by Dangling Piyush
    I want to implement Long polling Using Spring 3.2 DeferredResult. I got only this tutorial available on internet Long Polling with Spring MVC. It's a good tutorial but I could not understand it fully because I am pretty new to Spring MVC. So if anyone could explain me how to use DeferredResult for implenting long polling efficiently (server-side code) I would be grateful. I have posted this question before on Stack Overflow but got zero response so I thought of reposting it here again.

    Read the article

  • Google webmaster tools: changing address from domain name to subdomain

    - by Charliz
    So we originally have our blog on our main domain (for example, it would be on www.example.com). Now we have moved it to http://blog.example.com. My question is how do we change the address from www.example.com to blog.example.com. I read this http://www.google.com/support/webmasters/bin/answer.py?answer=83106 and it said make sure your site is main not a subdomain but I'm trying to move the site to a subdomain. Help.

    Read the article

  • Languages on embedded systems in aeronautic and spatial sector

    - by Niels
    I know that my question is very broad but a general answer would be nice. I would like to know which are the main languages used in aeronautic and spatial sector. I know that the OS which run on embedded systems are RTOS (Real time OS) and I think that, this languages must be checked correctly by different methods (formal methods, unit tests) and must permit a sure verification of whole process of a program.

    Read the article

  • MVC Portable Area Modules *Without* MasterPages

    - by Steve Michelotti
    Portable Areas from MvcContrib provide a great way to build modular and composite applications on top of MVC. In short, portable areas provide a way to distribute MVC binary components as simple .NET assemblies where the aspx/ascx files are actually compiled into the assembly as embedded resources. I’ve blogged about Portable Areas in the past including this post here which talks about embedding resources and you can read more of an intro to Portable Areas here. As great as Portable Areas are, the question that seems to come up the most is: what about MasterPages? MasterPages seems to be the one thing that doesn’t work elegantly with portable areas because you specify the MasterPage in the @Page directive and it won’t use the same mechanism of the view engine so you can’t just embed them as resources. This means that you end up referencing a MasterPage that exists in the host application but not in your portable area. If you name the ContentPlaceHolderId’s correctly, it will work – but it all seems a little fragile. Ultimately, what I want is to be able to build a portable area as a module which has no knowledge of the host application. I want to be able to invoke the module by a full route on the user’s browser and it gets invoked and “automatically appears” inside the application’s visual chrome just like a MasterPage. So how could we accomplish this with portable areas? With this question in mind, I looked around at what other people are doing to address similar problems. Specifically, I immediately looked at how the Orchard team is handling this and I found it very compelling. Basically Orchard has its own custom layout/theme framework (utilizing a custom view engine) that allows you to build your module without any regard to the host. You simply decorate your controller with the [Themed] attribute and it will render with the outer chrome around it: 1: [Themed] 2: public class HomeController : Controller Here is the slide from the Orchard talk at this year MIX conference which shows how it conceptually works:   It’s pretty cool stuff.  So I figure, it must not be too difficult to incorporate this into the portable areas view engine as an optional piece of functionality. In fact, I’ll even simplify it a little – rather than have 1) Document.aspx, 2) Layout.ascx, and 3) <view>.ascx (as shown in the picture above); I’ll just have the outer page be “Chrome.aspx” and then the specific view in question. The Chrome.aspx not only takes the place of the MasterPage, but now since we’re no longer constrained by the MasterPage infrastructure, we have the choice of the Chrome.aspx living in the host or inside the portable areas as another embedded resource! Disclaimer: credit where credit is due – much of the code from this post is me re-purposing the Orchard code to suit my needs. To avoid confusion with Orchard, I’m going to refer to my implementation (which will be based on theirs) as a Chrome rather than a Theme. The first step I’ll take is to create a ChromedAttribute which adds a flag to the current HttpContext to indicate that the controller designated Chromed like this: 1: [Chromed] 2: public class HomeController : Controller The attribute itself is an MVC ActionFilter attribute: 1: public class ChromedAttribute : ActionFilterAttribute 2: { 3: public override void OnActionExecuting(ActionExecutingContext filterContext) 4: { 5: var chromedAttribute = GetChromedAttribute(filterContext.ActionDescriptor); 6: if (chromedAttribute != null) 7: { 8: filterContext.HttpContext.Items[typeof(ChromedAttribute)] = null; 9: } 10: } 11:   12: public static bool IsApplied(RequestContext context) 13: { 14: return context.HttpContext.Items.Contains(typeof(ChromedAttribute)); 15: } 16:   17: private static ChromedAttribute GetChromedAttribute(ActionDescriptor descriptor) 18: { 19: return descriptor.GetCustomAttributes(typeof(ChromedAttribute), true) 20: .Concat(descriptor.ControllerDescriptor.GetCustomAttributes(typeof(ChromedAttribute), true)) 21: .OfType<ChromedAttribute>() 22: .FirstOrDefault(); 23: } 24: } With that in place, we only have to override the FindView() method of the custom view engine with these 6 lines of code: 1: public override ViewEngineResult FindView(ControllerContext controllerContext, string viewName, string masterName, bool useCache) 2: { 3: if (ChromedAttribute.IsApplied(controllerContext.RequestContext)) 4: { 5: var bodyView = ViewEngines.Engines.FindPartialView(controllerContext, viewName); 6: var documentView = ViewEngines.Engines.FindPartialView(controllerContext, "Chrome"); 7: var chromeView = new ChromeView(bodyView, documentView); 8: return new ViewEngineResult(chromeView, this); 9: } 10:   11: // Just execute normally without applying Chromed View Engine 12: return base.FindView(controllerContext, viewName, masterName, useCache); 13: } If the view engine finds the [Chromed] attribute, it will invoke it’s own process – otherwise, it’ll just defer to the normal web forms view engine (with masterpages). The ChromeView’s primary job is to independently set the BodyContent on the view context so that it can be rendered at the appropriate place: 1: public class ChromeView : IView 2: { 3: private ViewEngineResult bodyView; 4: private ViewEngineResult documentView; 5:   6: public ChromeView(ViewEngineResult bodyView, ViewEngineResult documentView) 7: { 8: this.bodyView = bodyView; 9: this.documentView = documentView; 10: } 11:   12: public void Render(ViewContext viewContext, System.IO.TextWriter writer) 13: { 14: ChromeViewContext chromeViewContext = ChromeViewContext.From(viewContext); 15:   16: // First render the Body view to the BodyContent 17: using (var bodyViewWriter = new StringWriter()) 18: { 19: var bodyViewContext = new ViewContext(viewContext, bodyView.View, viewContext.ViewData, viewContext.TempData, bodyViewWriter); 20: this.bodyView.View.Render(bodyViewContext, bodyViewWriter); 21: chromeViewContext.BodyContent = bodyViewWriter.ToString(); 22: } 23: // Now render the Document view 24: this.documentView.View.Render(viewContext, writer); 25: } 26: } The ChromeViewContext (code excluded here) mainly just has a string property for the “BodyContent” – but it also makes sure to put itself in the HttpContext so it’s available. Finally, we created a little extension method so the module’s view can be rendered in the appropriate place: 1: public static void RenderBody(this HtmlHelper htmlHelper) 2: { 3: ChromeViewContext chromeViewContext = ChromeViewContext.From(htmlHelper.ViewContext); 4: htmlHelper.ViewContext.Writer.Write(chromeViewContext.BodyContent); 5: } At this point, the other thing left is to decide how we want to implement the Chrome.aspx page. One approach is the copy/paste the HTML from the typical Site.Master and change the main content placeholder to use the HTML helper above – this way, there are no MasterPages anywhere. Alternatively, we could even have Chrome.aspx utilize the MasterPage if we wanted (e.g., in the case where some pages are Chromed and some pages want to use traditional MasterPage): 1: <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage" %> 2: <asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server"> 3: <% Html.RenderBody(); %> 4: </asp:Content> At this point, it’s all academic. I can create a controller like this: 1: [Chromed] 2: public class WidgetController : Controller 3: { 4: public ActionResult Index() 5: { 6: return View(); 7: } 8: } Then I’ll just create Index.ascx (a partial view) and put in the text “Inside my widget”. Now when I run the app, I can request the full route (notice the controller name of “widget” in the address bar below) and the HTML from my Index.ascx will just appear where it is supposed to.   This means no more warnings for missing MasterPages and no more need for your module to have knowledge of the host’s MasterPage placeholders. You have the option of using the Chrome.aspx in the host or providing your own while embedding it as an embedded resource itself. I’m curious to know what people think of this approach. The code above was done with my own local copy of MvcContrib so it’s not currently something you can download. At this point, these are just my initial thoughts – just incorporating some ideas for Orchard into non-Orchard apps to enable building modular/composite apps more easily. Additionally, on the flip side, I still believe that Portable Areas have potential as the module packaging story for Orchard itself.   What do you think?

    Read the article

  • Basis of definitions

    - by Yttrill
    Let us suppose we have a set of functions which characterise something: in the OO world methods characterising a type. In mathematics these are propositions and we have two kinds: axioms and lemmas. Axioms are assumptions, lemmas are easily derived from them. In C++ axioms are pure virtual functions. Here's the problem: there's more than one way to axiomatise a system. Given a set of propositions or methods, a subset of the propositions which is necessary and sufficient to derive all the others is called a basis. So too, for methods or functions, we have a desired set which must be defined, and typically every one has one or more definitions in terms of the others, and we require the programmer to provide instance definitions which are sufficient to allow all the others to be defined, and, if there is an overspecification, then it is consistent. Let me give an example (in Felix, Haskell code would be similar): class Eq[t] { virtual fun ==(x:t,y:t):bool => eq(x,y); virtual fun eq(x:t, y:t)=> x == y; virtual fun != (x:t,y:t):bool => not (x == y); axiom reflex(x:t): x == x; axiom sym(x:t, y:t): (x == y) == (y == x); axiom trans(x:t, y:t, z:t): implies(x == y and y == z, x == z); } Here it is clear: the programmer must define either == or eq or both. If both are defined, the definitions must be equivalent. Failing to define one doesn't cause a compiler error, it causes an infinite loop at run time. Defining both inequivalently doesn't cause an error either, it is just inconsistent. Note the axioms specified constrain the semantics of any definition. Given a definition of == either directly or via a definition of eq, then != is defined automatically, although the programmer might replace the default with something more efficient, clearly such an overspecification has to be consistent. Please note, == could also be defined in terms of !=, but we didn't do that. A characterisation of a partial or total order is more complex. It is much more demanding since there is a combinatorial explosion of possible bases. There is an reason to desire overspecification: performance. There also another reason: choice and convenience. So here, there are several questions: one is how to check semantics are obeyed and I am not looking for an answer here (way too hard!). The other question is: How can we specify, and check, that an instance provides at least a basis? And a much harder question: how can we provide several default definitions which depend on the basis chosen?

    Read the article

< Previous Page | 432 433 434 435 436 437 438 439 440 441 442 443  | Next Page >