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  • PHP/MySQL: Storing and retrieving UUIDS

    - by Greg
    I'm trying to add UUIDs to a couple of tables, but I'm not sure what the best way to store/retrieve these would be. I understand it's far more efficient to use BINARY(16) instead of VARCHAR(36). After doing a bit of research, I also found that you can convert a UUID string to binary with: UNHEX(REPLACE(UUID(),'-','')) Pardon my ignorance, but is there an easy way to this with PHP and then turn it back to a string, when needed, for readability? Also, would it make much difference if I used this as a primary key instead of auto_increment? EDIT: Found part of the answer: $bin = pack("h*", str_replace('-', '', $guid)); How would you unpack it?

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  • why do we have to send the const " type " reference instead of just the types name to the constructo

    - by hamza
    i m trying to make a simple program ( & yes , it is a homework ) that can generate Dates , & like most of normal people : i made my Class attributes private , i tried to send the same type that i m working on to the constructor but the complier have not accept it , i did some research & i found out that in cases like that people generously send a const "type" reference to the constructor witch meant to me that have not understand OOP well so why do we have to send the const " type " reference instead of just the types name to the constructor ? & please give me some links or websites for beginners PS : sorry for my English

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  • Storing And Using Microsoft User Account Credentials in SQL Server 2008 database

    - by user337501
    I'm not exactly positive how to word this for the sake of the title so please forgive me. Also I can't seem to figure out how to even google this question, so I'm hoping that I can get a lead in the right direction. Part of my software(VB.NET App) requires the ability to access/read/write a shared network folder. I have an option for the user to specify any credentials that might be needed to access said folder. I want to store these credentials given in the SQL Server database as part of the config (I have a table which contains configuration). My concern is that the password for the user account will be unencrpyted. Yet, if I encrypt the password the VB.NET App And/Or database will be unable to use the credentials for file i/o operations unless the Password is unencrypted before use. I'm fishing for suggestions on how to better handle this situation.

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  • International JRE6 or JDK6 or reading a file in "cp037" encoding scheme

    - by Reddy
    I have been trying to read a file in "cp037" encoding scheme using JAVA. I able to read a file in basic encoding schemes like UTF-8, UTF16 etc...After a bit of research on the internet i came to know that we need charset.jar or international version of JRE be installed to support extended encoding schemes. Can anyone send me a link for international version of JRE6 or JDK6. or is there any better way that i could read a file in cp037 encoding scheme. P.S: cp037 is a character encoding scheme supported by IBM Mainframes. All i need is to display a file in windows, which is being generated on IBM Mainframes machine, using a java program. Thanks in advance for your help... :-)

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  • How might one implement FileTimeToSystemTime?

    - by Billy ONeal
    Hello :) I'm writing a simple wrapper around the Win32 FILETIME structure. boost::datetime has most of what I want, except I need whatever date type I end up using to interpolate with Windows APIs without issues. To that end, I've decided to write my own things for doing this -- most of the operations aren't all that complicated. I'm implementing the TimeSpan - like type at this point, but I'm unsure how I'd implement FileTimeToSystemTime. I could just use the system's built-in FileTimeToSystemTime function, except FileTimeToSystemTime cannot handle negative dates -- I need to be able to represent something like "-12 seconds". How should something like this be implemented? Billy3

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  • How can I tell if a closed path contains a given point?

    - by Tom Seago
    In Android, I have a Path object which I happen to know defines a closed path, and I need to figure out if a given point is contained within the path. What I was hoping for was something along the lines of path.contains(int x, int y) but that doesn't seem to exist. The specific reason I'm looking for this is because I have a collection of shapes on screen defined as paths, and I want to figure out which one the user clicked on. If there is a better way to be approaching this such as using different UI elements rather than doing it "the hard way" myself, I'm open to suggestions. I'm open to writing an algorithm myself if I have to, but that means different research I guess.

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  • Python: Huge file reading by using linecache Vs normal file access open()

    - by user335223
    Hi, I am in a situation where multiple threads reading the same huge file with mutliple file pointers to same file. The file will have atleast 1 million lines. Eachline's length varies from 500 characters to 1500 characters. There won't "write" operations on the file. Each thread will start reading the same file from different lines. Which is the efficient way..? Using the Python's linecache or normal readline() or is there anyother effient way?

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  • Hebbian learning

    - by Bane
    I have asked another question on Hebbian learning before, and I guess I got a good answer which I accepted, but, the problem is that I now realize that I've mistaken about Hebbian learning completely, and that I'm a bit confused. So, could you please explain how it can be useful, and what for? Because the way Wikipedia and some other pages describe it - it doesn't make sense! Why would we want to keep increasing the weight between the input and the output neuron if the fire together? What kind of problems can it be used to solve, because when I simulate it in my head, it certainly can't do the basic AND, OR, and other operations (say you initialize the weights at zero, the output neurons never fire, and the weights are never increased!)

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  • Running MSBuild script on development machine

    - by devdigital
    Hi, I have an MSBuild script which performs a lot of tasks, as it is run on our build server. I want the script to be run each time a developer builds from Visual Studio on their local development machine, so that a) the build process they are runnning locally is the same as that run by the build server so any problems in the build can be identified immediately by the developer b) many of the operations of the build script are run on local builds, for example running of unit tests, generation of code coverage reports etc How is this possible in Visual Studio (2008)? Note I am running a single solution product with multiple projects.

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  • Where can I find soft-multiply and divide algorithms?

    - by srking
    I'm working on a micro-controller without hardware multiply and divide. I need to cook up software algorithms for these basic operations that are a nice balance of compact size and efficiency. My C compiler port will employ these algos, not the the C developers themselves. My google-fu is so far turning up mostly noise on this topic. Can anyone point me to something informative? I can use add/sub and shift instructions. Table lookup based algos might also work for me, but I'm a bit worried about cramming so much into the compiler's back-end...um, so to speak. Thanks!

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  • Question on Simple Look Up Tables [closed]

    - by CVS26
    Hi everyone... I'm doing some research on Simple Look Up Tables. I have : been thru wikipedia. Googled Look-up tables Browsed thedailywtf.com Been thru several websites illustrating/documenting look-up table code. Currently i am looking for any insight anyone can throw on the topic (LuTs). Also, I am specifically looking for any anecdotes one would like to share (again on LuTs). All content will be adequately acknowledge (or anonymised, if requested) in the article. Thank You

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  • Using the .where method in Rails3

    - by Elliot
    Hey Guys, I've just started using the .where method, and I'm a little bit confused about how to fully utilize it. I'd like to do something like: @books = Book.where(:author_id => 1 || 2) clearly I know that doesn't work, but I'm trying to demonstrate that I want some extra logic here. some "or" "and" "does not equal" etc. Any ideas for where I can research this? I was looking in the rails API but I didnt see anything that was that helpful. Thanks!

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  • Transaction within transaction

    - by user281521
    Hello, I want to know if open a transaction inside another is safe and encouraged? I have a method: def foo(): session.begin try: stuffs except Exception, e: session.rollback() raise e session.commit() and a method that calls the first one, inside a transaction: def bar(): stuffs try: foo() #<<<< there it is :) stuffs except Exception, e: session.rollback() raise e session.commit() if I get and exception on the foo method, all the operations will be rolled back? and everything else will work just fine? thanks!!

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  • How to limit data to users who own it without limiting admin users in CakePHP?

    - by cdburgess
    Currently I am writing an application where I have multiple users. They have data that should only be visible to them and not the other authenticated users in the system. I also have administrators who manage the system and have access to all of the information. What is the best way to limit users to their data without limiting admin users? Currently I am using a callback to limit the queries by user, but the admin will get the same limits. So I need to know a better way to do it. More importantly, the right way to do it. For example, I want the standard user to be able to see their user information only and be limited to CRUD operations on their information only. The admin, however, should be able to see ALL users and CRUD ALL user data. Any ideas?

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  • Time complexity O() of isPalindrome()

    - by Aran
    I have this method, isPalindrome(), and I am trying to find the time complexity of it, and also rewrite the code more efficiently. boolean isPalindrome(String s) { boolean bP = true; for(int i=0; i<s.length(); i++) { if(s.charAt(i) != s.charAt(s.length()-i-1)) { bP = false; } } return bP; } Now I know this code checks the string's characters to see whether it is the same as the one before it and if it is then it doesn't change bP. And I think I know that the operations are s.length(), s.charAt(i) and s.charAt(s.length()-i-!)). Making the time-complexity O(N + 3), I think? This correct, if not what is it and how is that figured out. Also to make this more efficient, would it be good to store the character in temporary strings?

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  • How to create a 'Hot or Not' website

    - by Casper
    Hi guys, I'd like to create a website with similar concept as 'Hot or Not' where users need to sign up to the website and then upload photos. Each photo can be given a description and some additional fields. Other users may comment and rate the photo entries. On top of that, users may favourite/bookmark (and remove) any photo entries and they're accessible via their profile page That's generally how the website will be. Can't decide on a CMS to use Somehow I'm at a crossroad here. I've done some research and found that Joomla has an extension that is able to pull this website off but the thing is I'm not that comfortable with using Joomla. I work with WordPress most of the time, but I can't seem to figure out how would I build this website with WordPress. Would using BuddyPress make it work? Would hiring a plugin developer to customize some plugins work? What do you guys think?

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  • Is there any reason why someone would want to create an Core Data model programmatically?

    - by mystify
    I wonder in which cases it would be good to make an NSManagedObjectModel completely programmatically, with NSEntityDescription instances and all this stuff. I'm that kind of person who prefers to code programmatically, rejecting Interface Builder. But when it comes to Core Data, I have a hard time figuring out why I should kill my time NOT using the nice Xcode Data Modeler tool. And since data models are stuck to a given state (except when you want to do some ugly migration operations where thinks probably go wrong and users get mad, really mad), I see no big sense in a data model that's made programmatically for the purpose of changing it all the time. Did I miss something?

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  • Making self-logging modules with Log::Log4perl

    - by Oesor
    Is there a way to use Log::Log4perl to make a smart self-logging module that logs its operations to a file even in the absence of the calling script not initializing Log4perl? As far as I can tell from the documentation, the only way to use Log4perl is to initialize it in the running script from a configuration, then modules implementing Log4perl calls log themselves based on the caller's Log4perl config. Instead, I'd like the modules to provide a default initialization config for Log4perl. This would provide the default file appender for the module's category. Then, I could override this behavior by initing Log4perl in the caller with a different config if needed, and everything would hopefully just work. Is this sort of defensive logging behavior possible or am I going to need to rely on initing Log4perl in every .pl script that calls the module I want logged?

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  • Boost Filesystem Library Visual C++ Compile Error

    - by John Miller
    I'm having the following issue just trying to compile/run some of the example programs with the Boost Filesystem Library. I'm using MS-Visual C++ with Visual Studio .NET (2003). I've installed the Boost libraries, version 1.38 and 1.39 (just in case there was a version problem) using the BoostPro installers. If I just try to include /boost/filesystem/operations.hpp I receive the following error: \boost_1_38\boost\system\error_code.hpp(230) : error C2039: 'type' : is not a member of 'boost::enable_if<boost::system::is_error_condition_enum<Cond,boost::detail::enable_if_default_T>' Any help is greatly appreciated. Thank you!

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  • A RAM error of big array

    - by flint
    I have a big file, more than 400M. In that file, there are 13496*13496 number, means 13496 rows and 13496 cols. I want to read them to a array. This is my code: _L1 = [[0 for col in range(13496)] for row in range(13496)] _L1file = open('distanceCMD.function.txt') while (i<13496): print "i="+str(i) _strlf = _L1file.readline() _strlf = _strlf.split('\t') _strlf = _strlf[:-1] _L1[i] = _strlf i += 1 _L1file.close() And this is my error massage: MemoryError: File "D:\research\space-function\ART3.py", line 30, in <module> _strlf = _strlf.split('\t')

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  • Do you draw the entire object?

    - by vbman11
    Hi I'm working on learning 3d game development and I'm starting with JavaScript and the html5 canvas and I was wondering if I were to have a 3d model do I draw the entire model(front, back, etc) and let the web browser decide what to render or should I try to just draw the sides that are in view of the camera? I ask this because I can see how it would be faster to do the latter of the 2 but that can get very complex and I'll need to do quite a bit more research to find how to do that. Thanks!!

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  • Ruby: Read large data from stdout and stderr of an external process on Windows

    - by BinaryMuse
    Greetings, all, I need to run a potentially long-running process from Ruby on Windows and subsequently capture and parse the data from the external process's standard output and error. A large amount of data can be sent to each, but I am only necessarily interested in one line at a time (not capturing and storing the whole of the output). After a bit of research, I found that the Open3 class would take care of executing the process and giving me IO objects connected to the process's standard output and error (via popen3). Open3.popen3("external-program.bat") do |stdin, out, err, thread| # Step3.profit() ? end However, I'm not sure how to continually read from both streams without blocking the program. Since calling IO#readlines on out or err when a lot of data has been sent results in a memory allocation error, I'm trying to continuously check both streams for available input, but not having much luck with any of my implementations. Thanks in advance for any advice!

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  • RESTful application validation. Mix of frontend/backend validation. How?

    - by Julian Davchev
    Hi. Using RESTful for all backend persistance and operations. I just pass data from frontend (by frontend I don't mean clientside but the part that is making use of the REST) to rest and data gets back success or no with validation errors if any. Thing is I have stuff that should be validated on frontend too..like csrf tokens, captcha etc. Only reasonable way is I mix validation coming from token/captcha checks and validation errors coming back from REST. Issue with this will be kinda automation as I wouldn't want form field names to map 1:1 with backend field names use by the REST documents. Any pointers ideas are more than welcome.

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  • What's exactly the nature of .Net Framework 3.5 Service Pack1?

    - by Richard77
    Hello, I did some recovery disk operations with my laptop because it became instable. Now, I'm about to re-install SQL Server 2008 Professional, but it keeps telling me that I need to install .net framework 3.5 with service pack1. What's strange is I was asked to do the same when I installed Visual Studio 2008 Professional earlier. I'd like to know: what's .Net Framework Service Pack1? is it One piece of software sitting on top of windows ? Several software having the same name so that Visual Studio has it, SQL Server also has it, and do on... And why the naming Service Pack1 behind .Net Framework? I'm really lost. Thanks for helping

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  • Best canvas for drawing in wxPython?

    - by Pablo Rodriguez
    I have to draw a graph of elements composing a topological model of a physical network. There would be nodes and arches, and the latter could be unidirectional or bidirectional. I would like to capture the clicking events for the nodes and the arches (to select the element and show its properties somewhere), and the dragging events for the nodes (to move them around) and arches (to connect or disconnect elements). I've done some research and I've narrowed the alternatives down to OGL (Object Graphics Library) and FloatCanvas. I would not like to go down to the DrawingContext, but it is not discarded if necessary. Which canvas option would you choose?

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