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• Can profiler templates be migrated to newer versions of SQL Profiler?

  - by EBarr

  Is it possible to migrate Profiler templates to newer versions of SQL Server? In my case I want to take my SQL 2008 templates to 2012. I've tried (1) a straight file copy and (2) an export/import. In both cases the older templates run, but cannot be modified. Modifications result in the following error: I've got a bunch of custom templates and I'm trying to avoid recreating them by hand. Although, I guess that is the fallback position. Thoughts?

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• bitfield mask calculation macro

  - by Aidan Cully

  We have a set of C macros, here, for using the preprocessor to do bitfield operations, and we run into warnings when attempting to use these macros in visual studio. The problem can be demonstrated very easily: #define BITFIELD_WIDTHMASK(Width) \ ((Width) >= 32 ? ~0x0ul : (1ul << (Width)) - 1) unsigned long foo(void) { return BITFIELD_WIDTHMASK(32); } Compiling this with MSVC yields the warning: test.c(12) : warning C4293: '<<' : shift count negative or too big, undefined behavior This isn't a behavior problem - the << operator won't be used in this case, and that should be detected at compile time. But does anyone have any suggestions about how to rewrite the macro to avoid the warning? Or, failing that, how to redesign the macro interface for this? Thanks in advance

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• CoreData and many NSArrayController

  - by unixo

  In my CoreData Application, I've an outline view on left of main window, acting as source list (like iTunes); on the right I display a proper view, based on outline selection. Each view has its components, such as table view, connected to array controller, owned by the specific view. Very often different views display same data, for example, a table view of the same entity. From a performance point of view, is better to have a single array controller per entity and share it between all views or does CoreData cache avoid memory waste?

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• Is SHA sufficient for checking file duplication? (sha1_file in PHP)

  - by wag2639

  Suppose you wanted to make a file hosting site for people to upload their files and send a link to their friends to retrieve it later and you want to insure files are duplicated where we store them, is PHP's sha1_file good enough for the task? Is there any reason to not use md5_file instead? For the frontend, it'll be obscured using the original file name store in a database but some additional concerns would be if this would reveal anything about the original poster. Does a file inherit any meta information with it like last modified or who posted it or is this stuff based in the file system? Also, is using a salt frivolous since security in regards of rainbow table attack mean nothing to this and the hash could later be used as a checksum? One last thing, scalability? initially, it's only going to be used for small files a couple of megs big but eventually... Edit 1: The point of the hash is primarily to avoid file duplication, not to create obscurity.

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• Assign values on multi-properties to a object

  - by Lu Lu

  I have a object which it was initialized before in a base class. In inherited class, I use this object and assign values on multi-properties to it. Example: this.Chart.X = 10; this.Chart.Y = 10; this.Chart.Width = 20; this.Chart.Height = 20; this.Chart.Background = Color.Red; However, I must repeat "this.Chart" many times. How to avoid this. Note that I don't want to re-create this object again because in the base class, it was initialized with some common values. Thanks.

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• Rails + simple role system through associative table

  - by user202411

  So I have the Ninja model which has many Hovercrafts through ninja_hovercrafts (which stores the ninja_id and the hovercraft_id). It is of my understanding that this kind of arrangement should be set in a way that the associative table stores only enough information to bind two different classes. But I'd like to use the associative table to work as a very streamlined authorization hub on my application. So i'd also like this table to inform my system if this binding makes the ninja the pilot or co-pilot of a given hovercraft, through a "role" field in the table. My questions are: Is this ugly? Is this normal? Are there methods built into rails that would help me to automagically create Ninjas and Hovercrafts associations WITH the role? For exemple, could I have a nested form to create both ninjas and hcs in a way that the role field in ninjas_hovercrafts would be also filled? If managing my application roles this way isn't a good idea, whats the non-resource heavy alternative (my app is being designed trying to avoid scalability problems such as excessive joins, includes, etc) thank you

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• What is the effect on record size of reordering columns in PostgreSQL?

  - by Summer

  Since Postgres can only add columns at the end of tables, I end up re-ordering by adding new columns at the end of the table, setting them equal to existing columns, and then dropping the original columns. So, what does PostgreSQL do with the memory that's freed by dropped columns? Does it automatically re-use the memory, so a single record consumes the same amount of space as it did before? But that would require a re-write of the whole table, so to avoid that, does it just keep a bunch of blank space around in each record? Thanks! ~S

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• Keeping track of dirty blocks on a block device

  - by mikeY

  I'm looking for a way to keep track of what blocks on a block device are modified after a point in time. How I eventually want to use this for is to keep two 2TB disks in sync, one which only comes online (connected through USB) once a month. Without knowing what blocks have been modified, I have to go through the whole 2TB every time. I'm using a recent GNU/Linux OS and have C and Python experience. I'm hoping to avoid writing kernel level code as I don't have any experience in that area whatsoever. My current theory is that there should be some hooks somewhere where my code can get called when a disk flush is performed. Any ideas?

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• Secure password transmission over unencrypted tcp/ip

  - by academicRobot

  I'm in the designing stages of a custom tcp/ip protocol for mobile client-server communication. When not required (data is not sensitive), I'd like to avoid using SSL for overhead reasons (both in handshake latency and conserving cycles). My question is, what is the best practices way of transmitting authentication information over an unencrypted connection? Currently, I'm liking SRP or J-PAKE (they generate secure session tokens, are hash/salt friendly, and allow kicking into TLS when necessary), which I believe are both implemented in OpenSSL. However, I am a bit wary since I don't see many people using these algorithms for this purpose. Would also appreciate pointers to any materials discussing this topic in general, since I had trouble finding any.

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• Paging Recordsets from SQL Serverside

  - by Jonno

  I've been banging my head off this one for a while. I want to call 1k records from a SQL database and page them per 100. In classic ASP (where I'm moving from) this was dead easy to do with ADODB but with VB using ADO.net I can't find a single way that doesn't involve stored procs (which I want to avoid for now). It seems really stupid to call all 1k and sort it programmatically. Edit: It's SQL Server 2005 / .net 4.0 / Visual Studio 2010. Edit 2: Just to reiterate, I have Googled extensively and don't want to use stored procedures. There are many ways to get paged data but everything I see involves paging the data in the program rather than from the server.

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• What are the common patterns in web programming?

  - by lankerisms

  I have been trying to write my first big web app (more than one cgi file) and as I kept moving forward with the rough prototype, paralelly trying to predict more tasks, this is the todo that got accumulated (In no particular order). * Validations and input sanitizations * Object versioning (to avoid edit conflicts. I dont want hard locks) * Exception handling * memcache * xss and injection protections * javascript * html * ACLs * phonetics in search, match and find duplicates (for form validation) * Ajaxify!!! (I have snipped off the project specific items.) I know that each todo will be quite tied up to its project and technologies used. What I am wondering though, is if there is a pattern in your todo items as well as the sequence in which you experienced guys have come across them.

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• How can I implement "real time" messaging on Google AppEngine?

  - by Freed

  I'm creating a web application on Google AppEngine where I want the user to be notified a quickly as possible after certain events occour. The problem is similar to say a chat server in that I need something happening on one connection (someone is writing a message in a chat room) to propagate to a number of other connections (other people in that chat room gets the message). To get speedy updates from the server to the client I'm planning on using long polling with XmlHttpRequest, hoping that AppEngine won't interfere other than possibly restriing the timeout. The real problem however is efficient notification between connections on AppEngine. Is there any support for this type of cross connection notification on AppEngine that does not involve busy-waiting? The only tools I can think of to do this at all is either using the data storage (slow) or memcache (unreliable), and none of them would let me avoid busy-waiting. Note: I know about XMPP support on AppEngine. It's related, but I want a browser based solution, sending messages to the users by XMPP is not an option.

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• How to use switch statement with Enumerations C#

  - by Maximus Decimus

  I want to use a switch statement in order to avoid many if's. So I did this: public enum Protocol { Http, Ftp } string strProtocolType = GetProtocolTypeFromDB(); switch (strProtocolType) { case Protocol.Http: { break; } case Protocol.Ftp: { break; } } but I have a problem of comparing an Enum and a String. So if I added Protocol.Http.ToString() there is another error because it allows only CONSTANT evaluation. If I change it to this switch (Enum.Parse(typeof(Protocol), strProtocolType)) It's not possible also. So, it's possible to use in my case a switch statement or not?

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• Exposing a "dumbed-down", read-only instance of a Model in GAE

  - by Blixt

  Does anyone know a clever way, in Google App Engine, to return a wrapped Model instance that only exposes a few of the original properties, and does not allow saving the instance back to the datastore? I'm not looking for ways of actually enforcing these rules, obviously it'll still be possible to change the instance by digging through its __dict__ etc. I just want a way to avoid accidental exposure/changing of data. My initial thought was to do this (I want to do this for a public version of a User model): class ReadOnlyUser(db.Model): display_name = db.StringProperty() @classmethod def kind(cls): return 'User' def put(self): raise SomeError() Unfortunately, GAE maps the kind to a class early on, so if I do ReadOnlyUser.get_by_id(1) I will actually get a User instance back, not a ReadOnlyUser instance.

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• JavaScript's Associative Array / Object can't be read in functions

  - by Matrym

  At the very beginning of the javascript file, I have: var lbp = {}; lbp.defaults = { minLength: 40 }; I can successfully alert it afterwards, with: alert(lbp.defaults.minLength); But as soon as I put it inside a function, when I alert, I get "Undefined". What gives, and how do I avoid this? Is it absolutely necessary to pass this variable into each function, for example, by doing: function(lbp) { alert(lbp.defaults.minLength); } I would have thought that defining it first, it would attain global scope and not be required to be passed in? Thanks in advance for enlightening me :)

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• How do you resolve the common collsision between type name and object name?

  - by Catskul

  Since the convention is to capitalize the first letter of public properties, the old c++ convention of initial capital for type names, and initial lowercase for non-type names does not prevent the classic name collision class FooManager { public BarManager BarManager { get; set; } // Feels very wrong. // Recommended naming convention? public int DoIt() { return Foo.Blarb + Foo.StaticBlarb; // 1st and 2nd Foo are two // different symbols } } class BarManager { public int Blarb { get; set; } public static int StaticBlarb { get; set; } } It seems to compile, but feels so wrong. Is there a recommend naming convention to avoid this?

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• scala jrebel superclass change

  - by coubeatczech

  hi, I'm using JRebel with Scala and I'm quite frequently experiencing the need for restart of server due to the fact that JRebel is unable to load a class if the superclass was changed. This is done mainly when I change anonymous functions as I can deduce from the JRebel error desription: Class 'mypackage.NewBook$$anonfun$2' superclass was changed from 'scala.runtime.AbstractFunction1' to 'scala.runtime.AbstractFunction2' and could not be reloaded. Is there any way, how can I design my code to avoid this? Does scala compiler take the functions, numbers them from one as they appear in source code?

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• R- delete rows in multiple columns by unique number

  - by Vincent Moriarty

  Given data like this C1<-c(3,-999.000,4,4,5) C2<-c(3,7,3,4,5) C3<-c(5,4,3,6,-999.000) DF<-data.frame(ID=c("A","B","C","D","E"),C1=C1,C2=C2,C3=C3) How do I go about removing the -999.000 data in all of the columns I know this works per column DF2<-DF[!(DF$C1==-999.000 | DF$C2==-999.000 | DF$C3==-999.000),] But I'd like to avoid referencing each column. I am thinking there is an easy way to reference all of the columns in a particular data frame aka: DF3<-DF[!(DF[,]==-999.000),] or DF3<-DF[!(DF[,(2:4)]==-999.000),] but obviously these do not work And out of curiosity, bonus points if you can me why I need that last comma before the ending square bracket as in: ==-999.000),]

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• Twitter search c#

  - by Lily

  Hi, I have implemented a method which manually scrapes the Search Twitter page and gets the tweets on different pages. But since there is a fast refresh rate, the method triggers an exception. Therefore I have decided to use TweetSharp API instead var search = FluentTwitter.CreateRequest() .AuthenticateAs(TWITTER_USERNAME, TWITTER_PASSWORD) .Users().SearchFor("dumbledore"); var result = search.Request(); var users = result.AsUsers(); this code was on the site. Does anyone know how I can avoid giving my credentials and retrieve from all users and not just the ones I have as friends? Thanks!

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• Remove .php extension (explicitly written) for friendly URL

  - by miquel

  htaccess to remove the .php extension of my site's files. RewriteEngine on RewriteBase / RewriteCond %{SCRIPT_FILENAME} !-d RewriteCond %{SCRIPT_FILENAME} !-f RewriteRule ^(.*)$ $1.php [L,QSA] Now, if I go to my site www.mysite.com/home works fine, it redirects to home.php but the URL is still friendly. But if I write this URL: www.mysite.com/home.php The home.php is served, and the URL is not friendly. How can I avoid this behavior? I want that if the user writes www.mysite.com/home.php, the URL displayed in the URL bar be www.mysite.com/home

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• Creating a virtual, data-driven section of a Wordpress-powered site

  - by lgomez

  Hello all, I want to create a plugin for wordpress to automatically serve pages containing data pulled from a provider's API. The API returns one or more records containing data for that record and I simply want to have the plugin intercept the request, call the API with parameters pulled from the request URI and display the data using a template that I can either let them upload to the server or let them copy and paste into the plugins admin settings. For example, I may want one of my wordpress installations to show products pulled from such an API under the url "example.com/products". The plugin would catch that request, extract the variables from the URL, call the API and render the template with the returned results. I'd like to avoid requiring editing the .htaccess file like some caching plugins do. Some of the admins of these pages won't know how to do that or simply won't have access to the .htaccess file. Thanks!

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• How can I close a SimpleModal dialog when the user clicks the Back button?

  - by Wally Hartshorn

  When a user clicks on a button or link, I use the SimpleModal jQuery plugin to display a dialog to overlay the entire page, preventing the user from clicking another button or link during the delay before the next page loads. (I'd like to avoid this, but that's an issue for another day.) After the next page displays, if the user clicks the Back button, the previous page still has the SimpleModal overlay displayed, preventing them from using the page. This is a problem. How can I cause the SimpleModal dialog to close automatically either when the leaves the page or when the user clicks the Back button to return to the page? I tried this without success: $("body").unload(function() { $.modal.close(); }); Thanks! Wally

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• Programming cookbook? [closed]

  - by user73669

  Possible Duplicate: What is the single most influential book every programmer should read? Hello With sites like The Daily WTF and recurring threads on Slashdot and elsewhere about bad programming, I figured that, to avoid people reinventing the wheel (badly or not), there should be a good, fat book on programming that would go through typical programming problems and show good, known algorithms, either in pseudo-code or some language with an easy syntax so that the language is not an issue. Here's the list of books on the subject I saw at my local computer bookstore. Can you recommend a couple, or add to this list if it's missing better options? The art of computer programming Code complete Masterminds of programming 97 things every programmer should know The passionate programmer Pragmatic thinking & learning Coders at work The algorithm design manual Algorithms and programming How to think about algorithms How to think like a programmer Why programs fail Beautiful data Beautiful code The productive programmer Solid code Write great code Clean code Programming language pragmatics Hello world Learning Processing Learn to program Thank you.

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• The C vs. C++ way

  - by amc

  Hi, So I have to write a program that will iterate through an image and record the pixel locations corresponding to each color pixel that appears in it. For example, given http://www.socuteurl.com/fishywishykissy I need to find the coordinates of all yellow, purple, dark pink, etc pixels. In C++ I would use a hash table to do this. I would iterate through the image, check each pixel's value, look up that value and either add to a vector of pixel coordinates if it were found or add a new entry to the table if the value were not already there. The problem is that I may need to write this program in pure C instead of C++. How would I go about doing this in C? I feel like implementing a hash table would be pretty obnoxious and error-prone: should I avoid doing that? I'm pretty inexperienced with C and have a fair amount of C++ experience, if that matters. Thanks.

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• What are the main reasons against the Windows Registry?

  - by dbemerlin

  If i want to develop a registry-like System for Linux, which Windows Registry design failures should i avoid? Which features would be absolutely necessary? What are the main concerns (security, ease-of-configuration, ...)? I think the Windows Registry was not a bad idea, just the implementation didn't fullfill the promises. A common place for configurations including for example apache config, database config or mail server config wouldn't be a bad idea and might improve maintainability, especially if it has options for (protected) remote access. I once worked on a kernel based solution but stopped because others said that registries are useless (because the windows registry is)... what do you think?

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