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  • Concepts a web application developer should know?

    - by iama
    I think it is imperative for web application developers to know the answers surrounding the following general questions on web development irrespective of the programming language/framework used. What authentication mechanisms HTTP offer & what are their pros and cons? Why should one go for FORMS authentication? How to secure authentication or for that matter any transactions via HTTP? How to maintain state in HTTP? What are the downsides to maintaining state via cookie & what happens when browsers disable them? Security issues like cross site scripting, session hijacking etc. What other questions a web developer should have answers for similar to the ones above that are programming language/web framework agnostic?

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  • ms sql server identity counterpart problem

    - by Guru
    hi there, I'm using MS Sql Server and I want to use identity constraint in it I know how to use it in following manner create table mytable ( c1 int primary key identity(1,1); ) the above code works fine but what if i want the identity column to have values as EMP001, EMP002,... instead of 1,2.... Thanks in advance, Guru

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  • innovation for technical high school

    - by gnuze
    I work in a high school in Italy. Our goal is forming computer programmers in 5 years. Nowaday, we teach vb.net on Win ( desktop applications using ADO on Access ), C on linux ( process, threads ) , C++ on Linux ( sockets TCP/UDP with UML ), and a bit of ASP.net, flash programming, PHP, Joomla and PIC Microcontrollers. We are looking for something innovative to add in our programs of study, but every teacher have a different point of view: we are debating about python, C#, Arduino, Silverlight and smartphones programming. Any suggestions? Tx in advance.

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  • Combining the UNIQUE and CHECK constraints

    - by Bobby
    I have a table with columns a b and c, and if c is false then I only want to allow insertions if columns a and b are unique, but if c is true then a and b do not need to be unique. Example: There can only be one (foo, bar, false) in the table, but no limit on how many (foo, bar, true) there can be. I tried something like CONSTRAINT blah UNIQUE (a,b) AND CHECK (C is TRUE) but I can't figure out the correct syntax.

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  • FluentNHibernate Many-To-One References where Foreign Key is not to Primary Key and column names are

    - by Todd Langdon
    I've been sitting here for an hour trying to figure this out... I've got 2 tables (abbreviated): CREATE TABLE TRUST ( TRUSTID NUMBER NOT NULL, ACCTNBR VARCHAR(25) NOT NULL ) CONSTRAINT TRUST_PK PRIMARY KEY (TRUSTID) CREATE TABLE ACCOUNTHISTORY ( ID NUMBER NOT NULL, ACCOUNTNUMBER VARCHAR(25) NOT NULL, TRANSAMT NUMBER(38,2) NOT NULL POSTINGDATE DATE NOT NULL ) CONSTRAINT ACCOUNTHISTORY_PK PRIMARY KEY (ID) I have 2 classes that essentially mirror these: public class Trust { public virtual int Id {get; set;} public virtual string AccountNumber { get; set; } } public class AccountHistory { public virtual int Id { get; set; } public virtual Trust Trust {get; set;} public virtual DateTime PostingDate { get; set; } public virtual decimal IncomeAmount { get; set; } } How do I do the many-to-one mapping in FluentNHibernate to get the AccountHistory to have a Trust? Specifically, since it is related on a different column than the Trust primary key of TRUSTID and the column it is referencing is also named differently (ACCTNBR vs. ACCOUNTNUMBER)???? Here's what I have so far - how do I do the References on the AccountHistoryMap to Trust??? public class TrustMap : ClassMap<Trust> { public TrustMap() { Table("TRUST"); Id(x => x.Id).Column("TRUSTID"); Map(x => x.AccountNumber).Column("ACCTNBR"); } } public class AccountHistoryMap : ClassMap<AccountHistory> { public AccountHistoryMap() { Table("TRUSTACCTGHISTORY"); Id (x=>x.Id).Column("ID"); References<Trust>(x => x.Trust).Column("ACCOUNTNUMBER").ForeignKey("ACCTNBR").Fetch.Join(); Map(x => x.PostingDate).Column("POSTINGDATE"); ); I've tried a few different variations of the above line but can't get anything to work - it pulls back AccountHistory data and a proxy for the Trust; however it says no Trust row with given identifier. This has to be something simple. Anyone? Thanks in advance.

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  • SQL error with script to create

    - by PapaDaniel
    I used the SQL Server management studio on a table with Create Script to New and did minor changes. Give me an error "Incorrect syntax near '('" for the "(" after "WITH" /* EventType Table Creation */ CREATE TABLE [EventType] ( [pkEventID] [int] IDENTITY(1,1) NOT NULL, [Description] [nvarchar](50) NOT NULL, [BeginDate] [datetime] NOT NULL, [EndDate] [datetime] NOT NULL, [Comments] [nvarchar](500) NOT NULL, CONSTRAINT [PK_EventType] PRIMARY KEY CLUSTERED ( [pkEventID] ASC ) WITH ( PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON ) ON [PRIMARY] ) ON [PRIMARY] GO

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  • libnet that properly calculates checksum on IPV6

    - by VeaEm
    I have recently started playing around with libnet and using it to generate IPV6 packets. I am very new at programming, however, I am quite happy with the library. I have one problem with it though. It seems that libnet currently does not have the ability to properly calculate checksums on IPV6 packets. Being so new to programming, I am not yet capable of fixing this problem (although I am learning, so that one day I can). I am curious, has anyone run across a version of the library that can do this properly? Thanks!

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  • Add save callback to a single ActiveRecord instance, is it possible?

    - by J. Pablo Fernández
    Is it possible to add a callback to a single ActiveRecord instance? As a further constraint this is to go on a library so I don't have control over the class (except to monkey-patch it). This is more or less what I want to do: def do_something_creazy message = Message.new message.on_save_call :do_even_more_crazy_stuff end def do_even_more_crazy_stuff(message) puts "Message #{message} has been saved! Hallelujah!" end

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  • Rails. Putting update logic in your migrations

    - by Daniel Abrahamsson
    A couple of times I've been in the situation where I've wanted to refactor the design of some model and have ended up putting update logic in migrations. However, as far as I've understood, this is not good practice (especially since you are encouraged to use your schema file for deployment, and not your migrations). How do you deal with these kind of problems? To clearify what I mean, say I have a User model. Since I thought there would only be two kinds of users, namely a "normal" user and an administrator, I chose to use a simple boolean field telling whether the user was an adminstrator or not. However, after I while I figured I needed some third kind of user, perhaps a moderator or something similar. In this case I add a UserType model (and the corresponding migration), and a second migration for removing the "admin" flag from the user table. And here comes the problem. In the "add_user_type_to_users" migration I have to map the admin flag value to a user type. Additionally, in order to do this, the user types have to exist, meaning I can not use the seeds file, but rather create the user types in the migration (also considered bad practice). Here comes some fictional code representing the situation: class CreateUserTypes < ActiveRecord::Migration def self.up create_table :user_types do |t| t.string :name, :nil => false, :unique => true end #Create basic types (can not put in seed, because of future migration dependency) UserType.create!(:name => "BASIC") UserType.create!(:name => "MODERATOR") UserType.create!(:name => "ADMINISTRATOR") end def self.down drop_table :user_types end end class AddTypeIdToUsers < ActiveRecord::Migration def self.up add_column :users, :type_id, :integer #Determine type via the admin flag basic = UserType.find_by_name("BASIC") admin = UserType.find_by_name("ADMINISTRATOR") User.all.each {|u| u.update_attribute(:type_id, (u.admin?) ? admin.id : basic.id)} #Remove the admin flag remove_column :users, :admin #Add foreign key execute "alter table users add constraint fk_user_type_id foreign key (type_id) references user_types (id)" end def self.down #Re-add the admin flag add_column :users, :admin, :boolean, :default => false #Reset the admin flag (this is the problematic update code) admin = UserType.find_by_name("ADMINISTRATOR") execute "update users set admin=true where type_id=#{admin.id}" #Remove foreign key constraint execute "alter table users drop foreign key fk_user_type_id" #Drop the type_id column remove_column :users, :type_id end end As you can see there are two problematic parts. First the row creation part in the first model, which is necessary if I would like to run all migrations in a row, then the "update" part in the second migration that maps the "admin" column to the "type_id" column. Any advice?

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  • Web Application Translation, methods and tools

    - by CiscoIPPhone
    I've developed a web application. It needs to be translated to languages other than English in the future, and ideally the translators shouldn't need to know HTML/JS/C++ to provide the translation. The server side of the web application is written in C++ and the majority of the localised text is in the HTML files. My question is: What approaches are there to translating web applications? - Are there any existing tools that would enable a translator who doesn't understand HTML to translate a site? Should I write an application that extracts the localised text from a html file and can re-substitute translated text? Do you just provide the html file to your translators to be localised? I'm aware the question isn't strictly programming related but the solution may involve programming and it may require some software engineering.

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  • Visual Studio CLR project

    - by Vit
    Hi, so I wanted to try my first CLR project in Visual C++. So I created console project, but since every tutorial I found about CLR programming was using C#, or windows forms, I just tried writing standart c++ Hello Word app using iostream (I think code isnt needed in this case) but I though it will give me some compile error, since iostream uses precompiled functions, and CLR app compiles into MSIL. I assumed that CLR programming using C++ means just using C++ syntax, but different functions for I/O and so. So, basicly, what I want to ask is, can any native console C++ app be compiled into MSIL and run by .NET framework?

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  • Why is RAISERROR misspelled? Or is it not?

    - by Jason
    Why isn't RAISERROR spelled RAISEERROR? Where is the second E? I could understand if it were some ancient keyword length constraint, but I wouldn't expect it to be a nine-character limit. Is RAIS or RROR a technical word such that "raise-error" is just a mis-reading? Are its (immediate) origins in a different language? I've searched Google but not finding much on the subject.

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  • As a consultant should I charge my clients for developing specs?

    - by Chris
    I'm trying to transition into some programming consulting work. A friend of my former employer is interested in having me "develop a spec," which I take to mean come up with some technology requirements and time estimates (e.g. milestones). Do developers normally charge for this? I'm imagining it's basically the same kind of workload that creating a bid for a project would take. On one hand, consultants don't get paid for the time they put into the legwork of a bid. On the other hand, this is probably go to be more than a couple hours of work, and my time is valuable. Any advice? Any sites besides SO I could go to get advice with this kind of stuff? (Sorry if this isn't programming-related enough for StackOverflow! I don't know where else to get advice!)

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  • Incorrect syntax near ','.

    - by jeffreyshek
    I get the following error from the SQL Script I am trying to run: Msg 102, Level 15, State 1, Line 10 Incorrect syntax near ','. This is the SQL script: IF NOT EXISTS (SELECT * FROM dbo.sysobjects WHERE id = OBJECT_ID(N'[dbo].HDDB_DataSource]') AND OBJECTPROPERTY(id, N'IsUserTable') = 1) BEGIN CREATE TABLE [dbo].[HDDB_DataSource]( [ID] [int] IDENTITY(1,1) NOT NULL, [Name] [nvarchar](255) NOT NULL, [Type] [nvarchar](50) NOT NULL, [XmlFileName] [nvarchar](255) NULL, [ConnectionString] [nvarchar](255) NULL), CONSTRAINT [PK_DataSource] PRIMARY KEY CLUSTERED ( [ID] ASC ) ON [PRIMARY] ) ON [PRIMARY] END I am using SQL Server 2005 if that helps. Jeff

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  • Good portfolio projects

    - by David
    Hi, I am a recent graduate and am looking to start a career in web development. Its kind of a catch 22 at the moment as I have a fair bit of programming experience from university but not really in web development and to get a job in web development a portfolio is typically required. So, I am looking to start a building a few application in order to have something to show potential employers. Im more into the backend stuff although am just as comfortable with front end development. Does anyone have any thoughts on some potential projects that would be both relatively quick (as i need to get a job soon!) to build but show off enough programming knowlege / skills to be impressive to employers. At the moment i am also learning to use the zend framework and I would hope to find work using such a framework (mvc). My initial thoughts would be things like a webmail app or maybe a custom CMS. Any ideas would be greatley appreciated.

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  • Linux periodically "losing" ability to connect to server via SSH?

    - by gct
    I know this isn't exactly a programming question, but it popped up in my use of git for programming projects at least. I've got a web server that I use to host my git repos on, but my ubuntu box seems to "lose" the ability to connect to it via SSH. I'll get a "connection refused" error when I try to ssh or use git. Rebooting my local machine will fix the problem, but only temporarily. I can still connect to the web interface just fine, and the problem manifests with other servers as well. I've been working around it by pulling my changes over to my laptop and pushing from there, but that's sub-optimal as you can imagine. Has anyone seen something like this? I'd be tempted to say it's some kind of IP caching problem, but I can't connect even using the IP address of the server directly... Running Ubuntu 9.04

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  • Interview - Program on Computer

    - by Gilad Naor
    Spent some time searching, couldn't find exactly what I'm after. We like giving hands-on programming exercises as part of the interview process. The interviewee gets a laptop, with the editor and compiler of his choice. He or she then get a programming exercise and has about an hour to code it. Depending on the nature of the question, internet access is either allowed or forbidden. I'm looking for good general questions for a junior developer. I don't care what language they choose to program in. C++ is as good as Python or Scheme, as long as (s)he can program in it (this rules out "can you write a correct copy-constructor" style questions). I just want to see how they code, if their code is self-documenting, if they write tests, check edge-cases, etc. What kind of questions would you ask?

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  • Meaning of Primary Key to Microsoft SQL Server 2008

    - by usr
    What meaning does the concept of a primary key have to the database engine of SQL Server? I don't mean the clustered/nonclustered index created on the "ID" column, i mean the constraint object "primary key". Does it matter if it exists or not? Alternatives: alter table add primary key clustered alter table create clustered index Does it make a difference?

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  • Collision point of 2 curves in a 3d-room

    - by Frank
    Hello, i am programming a small game for quite some time. We started coding a small FPS-Shooter inside of a project at school to get a bit experience using directX. I dont know why, but i couldnt stop the project and started programming at home aswell. At the moment i am trying to create some small AI. Of cause thats definatlly not easy, but thats my personal goal anyways. The topic could prolly fill multiple books hehe. I've got the walking part of my bots done so far. They walk along a scriped path. I am not working on the "aiming" of the bots. While programming that i hit on some math problem i couldnt solve yet. I hope of your input on this to help me get further. Concepts, ideas and everything else are highly appreciated. Problem: Calculate the position (D3DXVECTOR3) where the curve of the projectile (depends on gravity, speed), hit the curved of the enemys walking path (depends on speed). We assume that the enemy walks in a constant line. Known variables: float projectilSpeed = 2000 m/s //speed of the projectile per second float gravitation = 9.81 m/s^2 //of cause the gravity lol D3DXVECTOR3 targetPosition //position of the target stored in a vector (x,y,z) D3DXVECTOR3 projectilePosition //position of the projectile D3DXVECTOR3 targetSpeed //stores the change of the targets position in the last second Variabledefinition ProjectilePosition at time of collision = ProjectilePos_t TargetPosition at time of collision = TargetPos_t ProjectilePosition at time 0, now = ProjectilePos_0 TargetPosition at time 0, now = TargetPos_0 Time to impact = t Aim-angle = theta My try: Found a formular to calculate "drop" (Drop of the projectile based on the gravity) on Wikipedia: float drop = 0.5f * gravity * t * t The speed of the projectile has a horizontal and a vertical part.. Found a formular for that on wikipedia aswell: ProjectilVelocity.x = projectilSpeed * cos(theta) ProjectilVelocity.y = projectilSpeed * sin(theta) So i would assume this is true for the projectile curve: ProjectilePos_t.x = ProjectilePos_0.x + ProjectileSpeed * t ProjectilePos_t.y = ProjectilePos_0.y + ProjectileSpeed * t + 0.5f * gravity * t * t ProjectilePos_t.z = ProjectilePos_0.z + ProjectileSpeed * t The target walk with a constant speed, so we can determine his curve by this: TargetPos_t = TargetPos_0 + TargetSpeed * D3DXVECTOR3(t, t, t) Now i dont know how to continue. I have to solve it somehow to get a hold on the time to impact somehow. As a basic formular i could use: float time = distanz / projectileSpeed But that wouldnt be truly correct as it would assume a linear "Trajectory". We just find this behaivor when using a rocket. I hope i was able to explain the problem as much as possible. If there are questions left, feel free to ask me! Greets from germany, Frank

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  • UIImageView "Sprite Movement" How?

    - by Tate Allen
    Hi all, I am trying to make a game for the iPhone/iPod Touch. I am somewhat new to iPhone programming and extremely new to iPhone game programming so try to bear with me if this is a stupid question. How to I make my character, a UIImageView, move to the right or left, along the x axis. Just a simple translation across the screen. This is very frustrating so if you could link me to a tutorial or something like that, it would be much appreciated. Thanks in advance, Tate

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  • What's the ROI of using a build tool like ant or nant?

    - by leeand00
    To me this sounds like a really stupid question. Why would you not use a build tool? However, I need to explain my co-worker why he should be using a build tool of some sort. He's getting really into the idea of working as a team with more programmers, but he isn't understanding the bigger picture of what needs to change in the build process in order to work with a larger team; (i.e. defensive programming/unit testing your code, having a bug database, programming modular libraries, and using sub-repositories to store modules in version control. This is a rather large stack of technologies that I need to prove the ROI of...so I figured I'd start with the ROI of using a build tool rather than just...say...clicking compile.

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  • How can I transition from a front-end career to back-end career?

    - by jexx2345
    Hello, In 2004, I received my B.S. in Computer Science using mostly Java for programming. Since then, I have been hired for purely front-end positions in large companies through recruiters, doing primarily HTML/CSS, Javascript/jQuery, and OOP Actionscript 3. While I definitely have respect for the front-end, and have learned much, I feel very unfulfilled and would love to move into back-end for the more complex programming I was doing in school. My target platform of choice is ASP.Net 3.5 (C#). With a resume that has absolutely no .Net or back-end experience, how can I transition into a junior back-end job? I am currently freelancing a .Net e-commerce site, and plan to build a portfolio showcasing some apps (e-commerce mvc, blog, etc), while learning the technology. Is having a Bachelors in CS enough or should I look into getting .Net certified? Is showing course-work still relevant to an employer even though it was from 6 years ago? Thank you

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