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  • Make exact copy of USB stick [closed]

    - by Andrius Palivonas
    There's this school software on a USB drive. It only runs, when the stick they gave is plugged in. Cloning the drive with dd command didn't work. I'm guessing it checks the hardware ID of the flash drive. Is there any way to change drives information? I guess not, but is it possible to create a virtual flash drive with exactly same hardware id and all other read-only information that the software is most probably checking. EDIT: The paper math books we have dont' have answers. So when I'm doing homework I have no idea if did it right. The electronic version does have the answers. The publisher didn't put them into paper version because of simple reason - money. They would have to republish the book if some answers are found to be wrong. So I feel no shame trying to pirate that software, because publishers are ruining our math education.

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  • Can two threads of the same process produce the same GUID?

    - by mark
    Dear ladies and sirs. If two threads in a process generate a new GUID concurrently using .NET API (Guid.NewGuid()) is it possible that the two GUIDs will be identical? Thanks. UPDATE I want to get practical. I know that it is widely assumed that GUIDs are unique for all practical purposes. I am wondering if I can treat GUIDS produced by the different threads of the same process in the same manner.

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  • mediatek 7630e 802.11 wifi bgn adapter failed in hp probook G1

    - by user257026
    id: network description: Network controller product: MT7630e 802.11bgn Wireless Network Adapter vendor: MEDIATEK Corp. physical id: 0 bus info: pci@0000:04:00.0 version: 00 width: 32 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list configuration: latency = 0 resources: memory : b0600000-b06fffff THIS IS MY WIFI driver details of my notebook pc.... BY the way.. recently I have installed ubuntu 14.04 LTS .....my every hardware is working properly except wifi adapter.... in windows it(wifi) was also working properly.. from hp driver center I have download linux kernel driver package ..Actually those driver package was rpm package ...then i have convert it to .dev file using alien...but the true fact is no result though..... again,previously released ubuntu version(such as 12.04LTS) causes the same issue ...those versions have same bugs there.. after googling web i have few results but no reliable outcomes to solve my problem(wifi issue) ..... As I am new user in ubuntu I cannot able to solve the problem drastically like pro(superuser).. https://answers.launchpad.net/ubuntu/+question/243203 How do I get a Mediatek MT7630E 802.11bgn Wi-Fi Adapter working? here two links about my issuses but I am confused what can i do (feeling meh)??? is there anyone who can help me in this issues...?? my notebook model is HP probook 450G1 Question #243203 : Questions : Ubuntu My HP laptop uses MediaTek's (MEDIATEK Corp.) MT7630e 802.11bgn Wireless Network Adapter. I cannot access wifi after installing Ubuntu myself and there are no drivers available - or so it seems. Apparantly some laptops which use this card came with Ubuntu pre-installed, with working drivers. These d… answers.launchpad.net Question #243203 : Questions : Ubuntu My HP laptop uses MediaTek's (MEDIATEK Corp.) MT7630e 802.11bgn Wireless Network Adapter. I cannot access wifi after installing Ubuntu myself and there are no drivers available - or so it... ANSWERS.LAUNCHPAD.NET

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  • SQL SERVER – Weekly Series – Memory Lane – #037

    - by Pinal Dave
    Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 Convert Text to Numbers (Integer) – CAST and CONVERT If table column is VARCHAR and has all the numeric values in it, it can be retrieved as Integer using CAST or CONVERT function. List All Stored Procedure Modified in Last N Days If SQL Server suddenly start behaving in un-expectable behavior and if stored procedure were changed recently, following script can be used to check recently modified stored procedure. If a stored procedure was created but never modified afterwards modified date and create a date for that stored procedure are same. Count Duplicate Records – Rows Validate Field For DATE datatype using function ISDATE() We always checked DATETIME field for incorrect data type. One of the user input date as 30/2/2007. The date was sucessfully inserted in the temp table but while inserting from temp table to final table it crashed with error. We had now task to validate incorrect date value before we insert in final table. Jr. Developer asked me how can he do that? We check for incorrect data type (varchar, int, NULL) but this is incorrect date value. Regular expression works fine with them because of mm/dd/yyyy format. 2008 Find Space Used For Any Particular Table It is very simple to find out the space used by any table in the database. Two Convenient Features Inline Assignment – Inline Operations Here is the script which does both – Inline Assignment and Inline Operation DECLARE @idx INT = 0 SET @idx+=1 SELECT @idx Introduction to SPARSE Columns SPARSE column are better at managing NULL and ZERO values in SQL Server. It does not take any space in database at all. If column is created with SPARSE clause with it and it contains ZERO or NULL it will be take lesser space then regular column (without SPARSE clause). SP_CONFIGURE – Displays or Changes Global Configuration Settings If advanced settings are not enabled at configuration level SQL Server will not let user change the advanced features on server. Authorized user can turn on or turn off advance settings. 2009 Standby Servers and Types of Standby Servers Standby Server is a type of server that can be brought online in a situation when Primary Server goes offline and application needs continuous (high) availability of the server. There is always a need to set up a mechanism where data and objects from primary server are moved to secondary (standby) server. BLOB – Pointer to Image, Image in Database, FILESTREAM Storage When it comes to storing images in database there are two common methods. I had previously blogged about the same subject on my visit to Toronto. With SQL Server 2008, we have a new method of FILESTREAM storage. However, the answer on when to use FILESTREAM and when to use other methods is still vague in community. 2010 Upper Case Shortcut SQL Server Management Studio I select the word and hit CTRL+SHIFT+U and it SSMS immediately changes the case of the selected word. Similar way if one want to convert cases to lower case, another short cut CTRL+SHIFT+L is also available. The Self Join – Inner Join and Outer Join Self Join has always been a noteworthy case. It is interesting to ask questions about self join in a room full of developers. I often ask – if there are three kinds of joins, i.e.- Inner Join, Outer Join and Cross Join; what type of join is Self Join? The usual answer is that it is an Inner Join. However, the reality is very different. Parallelism – Row per Processor – Row per Thread – Thread 0  If you look carefully in the Properties window or XML Plan, there is “Thread 0?. What does this “Thread 0” indicate? Well find out from the blog post. How do I Learn and How do I Teach The blog post has raised three very interesting questions. How do you learn? How do you teach? What are you learning or teaching? Let me try to answer the same. 2011 SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Day 7 of 31 What are Different Types of Locks? What are Pessimistic Lock and Optimistic Lock? When is the use of UPDATE_STATISTICS command? What is the Difference between a HAVING clause and a WHERE clause? What is Connection Pooling and why it is Used? What are the Properties and Different Types of Sub-Queries? What are the Authentication Modes in SQL Server? How can it be Changed? SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Day 8 of 31 Which Command using Query Analyzer will give you the Version of SQL Server and Operating System? What is an SQL Server Agent? Can a Stored Procedure call itself or a Recursive Stored Procedure? How many levels of SP nesting is possible? What is Log Shipping? Name 3 ways to get an Accurate Count of the Number of Records in a Table? What does it mean to have QUOTED_IDENTIFIER ON? What are the Implications of having it OFF? What is the Difference between a Local and a Global Temporary Table? What is the STUFF Function and How Does it Differ from the REPLACE Function? What is PRIMARY KEY? What is UNIQUE KEY Constraint? What is FOREIGN KEY? SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Day 9 of 31 What is CHECK Constraint? What is NOT NULL Constraint? What is the difference between UNION and UNION ALL? What is B-Tree? How to get @@ERROR and @@ROWCOUNT at the Same Time? What is a Scheduled Job or What is a Scheduled Task? What are the Advantages of Using Stored Procedures? What is a Table Called, if it has neither Cluster nor Non-cluster Index? What is it Used for? Can SQL Servers Linked to other Servers like Oracle? What is BCP? When is it Used? SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Day 10 of 31 What Command do we Use to Rename a db, a Table and a Column? What are sp_configure Commands and SET Commands? How to Implement One-to-One, One-to-Many and Many-to-Many Relationships while Designing Tables? What is Difference between Commit and Rollback when Used in Transactions? What is an Execution Plan? When would you Use it? How would you View the Execution Plan? SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Day 11 of 31 What is Difference between Table Aliases and Column Aliases? Do they Affect Performance? What is the difference between CHAR and VARCHAR Datatypes? What is the Difference between VARCHAR and VARCHAR(MAX) Datatypes? What is the Difference between VARCHAR and NVARCHAR datatypes? Which are the Important Points to Note when Multilanguage Data is Stored in a Table? How to Optimize Stored Procedure Optimization? What is SQL Injection? How to Protect Against SQL Injection Attack? How to Find Out the List Schema Name and Table Name for the Database? What is CHECKPOINT Process in the SQL Server? SQL SERVER – Interview Questions and Answers – Frequently Asked Questions – Day 12 of 31 How does Using a Separate Hard Drive for Several Database Objects Improves Performance Right Away? How to Find the List of Fixed Hard Drive and Free Space on Server? Why can there be only one Clustered Index and not more than one? What is Difference between Line Feed (\n) and Carriage Return (\r)? Is It Possible to have Clustered Index on Separate Drive From Original Table Location? What is a Hint? How to Delete Duplicate Rows? Why the Trigger Fires Multiple Times in Single Login? 2012 CTRL+SHIFT+] Shortcut to Select Code Between Two Parenthesis Shortcut key is CTRL+SHIFT+]. This key can be very useful when dealing with multiple subqueries, CTE or query with multiple parentheses. When exercised this shortcut key it selects T-SQL code between two parentheses. Monday Morning Puzzle – Query Returns Results Sometimes but Not Always I am beginner with SQL Server. I have one query, it sometime returns a result and sometime it does not return me the result. Where should I start looking for a solution and what kind of information I should send to you so you can help me with solving. I have no clue, please guide me. Remove Debug Button in SSMS – SQL in Sixty Seconds #020 – Video Effect of Case Sensitive Collation on Resultset Collation is a very interesting concept but I quite often see it is heavily neglected. I have seen developer and DBA looking for a workaround to fix collation error rather than understanding if the side effect of the workaround. Switch Between Two Parenthesis using Shortcut CTRL+] Earlier this week I wrote a blog post about CTRL+SHIFT+] Shortcut to Select Code Between Two Parenthesis, I received quite a lot of positive feedback from readers. If you are a regular reader of the blog post, you must be aware that I appreciate the learning shared by readers. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Why are we as an industry not more technically critical of our peers? [closed]

    - by Jarrod Roberson
    For example: I still see people in 2011 writing blog posts and tutorials that promote setting the Java CLASSPATH at the OS environment level. I see people writing C and C++ tutorials dated 2009 and newer and the first lines of code are void main(). These are examples, I am not looking for specific answers to the above questions, but to why the culture of accepting sub-par knowledge in the industry is so rampant. I see people posting these same type of empirically wrong suggestions as answers on www.stackoverflow.com and they get lots of up votes and practically no down votes! The ones that get lots of down votes are usually from answering a question that wasn't asked because of lack of reading for comprehension skills, and not incorrect answers per se. Is our industry that ignorant as a whole, I can understand the internet in general being lazy, apathetic and un-informed but our industry should be more on top of things like this and way more critical of people that are promoting bad habits and out-dated techniques and information. If we are really an engineering discipline, why aren't people held to a higher standard as they are in other engineering disciplines? I want to know why people accept bad advice, poor practices as the norm and are not more critical of their peers in the software industry.?

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  • What is the best way to track / record the current programming project you work on? [duplicate]

    - by user2424160
    This question already has an answer here: Methodology for Documenting Existing Code Base 6 answers When do you start documenting the code? 13 answers Where should a programmer explain the extended logic behind the code? 5 answers I have been in this problem for long time and I want to know how it's done in real / big companies project? Suppose I have the project to build a website. Now I divide the project into sub tasks and do it. But you know that suppose I have task1 in hand like export the page to pdf. Now I spend 3 days to do that , came across various problems, many Stack Overflow questions and in the end I solve it. Now 4 months after someone told me that there is some error in the code. Now by that I completely forgot about (60%) of how I did it and why I do this way. I document the code but I can't write the whole story of that in the code. Then I have to spend much time on code to find what was the problem so that I added this line etc. I want to know that is there any way that i can log steps in completing the project. So that I can see how I end up with code, what errors I got, what questions I asked on SO and etc. How people do it in real time? Which software to use? I know in our project management software called JIRA we have tasks but that does not cover what steps I took to solve that tasks. What is the best way so that when I look back at my 2 year old project, I know how I solve particular task?

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  • Returning Value of Radio Button Jquery [migrated]

    - by Jerry Walker
    I am trying to figure out why, when I run this code, I am getting undefined for my correct answers. $(document).ready (function () { // var answers = [["Fee","Fi","Fo"], ["La","Dee","Da"]], questions = ["Fee-ing?", "La-ing?"], corAns = ["Fee", "La"]; var counter = 0; var $facts = $('#main_ .facts_div'), $question = $facts.find('.question'), $ul = $facts.find('ul'), $btn = $('.myBtn'); $btn.on('click', function() { if (counter < questions.length) { $question.text(questions[counter]); var ansstring = $.map(answers[counter], function(value) { return '<li><input type="radio" name="ans" value="0"/>' + value + '</li>'}).join(''); $ul.html(ansstring); var currentAnswers = $('input[name="ans"]:checked').map(function() { return this.val(); }).get(); var correct = 0; if (currentAnswers[counter]==corAns[counter]) { correct++; } } else { $facts.text('You are done with the quiz ' + correct); $(this).hide(); } counter++; }); // }); It is quite long and I'm sorry about that, but I don't really know how tostrip it down. I also realize this isn't the most elegant way to do this, but I just want to know why I can't seem to get my radio values. I will add the markup as well if anyone wants.

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  • How Can I Effectively Interview an Oracle Candidate?

    - by Tim Medora
    First, I browsed through SO for matching questions and didn't find one, but please point me in the right direction if this exact question has already been asked. I work with and around programmers of various skill levels on various platforms. I would consider my skills to be strong in terms of relational database design, query development, and basic performance tuning and administration. I'm mid-level when it comes to database theory. My team is looking to me to ensure that we have the best talent on staff, in this case, an engineer experienced in Oracle administration. To me, a well-rounded database administrator, regardless of platform, should also be competent in developing against the database so that is also a requirement. However my database skills are centralized around SQL Server 200x with experience in a few other products like SAP MaxDB, Access, and FoxPro. How can I thoroughly assess the skills of an Oracle engineer? I can ask high-level database theory questions and talk about routine tasks that are common across platforms, but I want to dig deep enough that I can be confident in the people I hire. Normally, I would alternate very specific questions that have a right/wrong answer with architectural questions that might have several valid answers. Does anyone have an interview template, specific questions, or any other knowledge that they can share? Even knowing the meaningful Oracle-related certifications would be a help. Thank you. EDIT: All the answers have been very helpful so far and I have given upvotes to everyone. I'm surprised that there are already 3 close votes on this question as "off topic". To be clear, I am specifically asking how a MS SQL Server engineer (like myself) can effectively interview a person with different but symbiotic skills. The question has already received specific, technical answers which have improved my own database design and programming skills. If this is more appropriate as a community wiki, please convert it.

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  • Boundary conditions for testing

    - by Loggie
    Ok so in a programming test I was given the following question. Question 1 (1 mark) Spot the potential bug in this section of code: void Class::Update( float dt ) { totalTime += dt; if( totalTime == 3.0f ) { // Do state change m_State++; } } The multiple choice answers for this question were. a) It has a constant floating point number where it should have a named constant variable b) It may not change state with only an equality test c) You don't know what state you are changing to d) The class is named poorly I wrongly answered this with answer C. I eventually received feedback on the answers and the feedback for this question was Correct answer is a. This is about understanding correct boundary conditions for tests. The other answers are arguably valid points, but do not indicate a potential bug in the code. My question here is, what does this have to do with boundary conditions? My understanding of boundary conditions is checking that a value is within a certain range, which isn't the case here. Upon looking over the question, in my opinion, B should be the correct answer when considering the accuracy issues of using floating point values.

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  • What is meant by "no password set" for root account (and otthers)?

    - by MMA
    Several years back, we were more accustomed to changing to the root account using the su command. First, we switched to the root account, and then executed those root commands. Now we are more accustomed to using the sudo command. But we know that the root account is there. We can readily find the home directory of user root. $ ls -ld /root/ drwx------ 18 root root 4096 Oct 22 17:21 /root/ Now my point is, it is stated that "the root password in Ubuntu is left unset". Please see the answers to this question. Most of the answers have something to this effect in the first paragraph. One or two answers further state that "the account is left disabled". Now my (primary) questions are, What is meant by an unset password? Is it blank? Is it null? Or something else more cryptic? How does the account becomes enabled once I set password for it? (sudo password root) In order get a better understanding, I checked the /etc/shadow file. Since I have already set a password for the root account, I can no longer see what is there (encrypted password). So, I created another account and left it disabled. The corresponding entry in the /etc/shadow file is, testpassword:!:16020:0:99999:7::: Now perhaps my above queries need to be changed to, what does an ! in password field mean? Other encrypted passwords are those very long cryptic strings. How come this encrypted form is only one character long? And does an account become disabled if I put an ! in the (encrypted) password field?

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  • High-level description of how experimental C++ features are developed?

    - by Praxeolitic
    Herb Sutter in a video answers a question about the concepts proposal considered for C++11 and from his remarks it sounds like multiple groups offered prototype implementations but all of them left concerns about slow compile times. The comment surprised me because it suggests that, at least in some cases, the prototypes being developed are not just proofs of concept -- they're even expected to perform. All the work that must take has me curious. For mature languages, especially C++, how are experimental language features developed? Is it much different from developing a compiler that implements a standard? Does a developer have a sense of if it will work and perform or even if it ever could? What are the most time consuming parts and are any parts surprisingly easier than one might expect? The question is not what does the C++ standards committee do, but rather the part that comes before. When an experimental implementation for a proposal is being put together and there aren't any completely solidified rules, how is the sausage made? I'm not a professional compiler developer nor do I expect answers with step by step accounts. I'd like a high-level idea of how this would be done or if there are any general patterns at all. I don't know what to expect from the answers but even if there are no rules to the process and the small number of people who do this just cowboy it and then, for stuff that worked out, write up the "official version" as a proposal, that answer would still be informative.

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  • SQL SERVER – A Puzzle – Swap Value of Column Without Case Statement

    - by pinaldave
    For the last few weeks, I have been doing Friday Puzzles and I am really loving it. Yesterday I received a very interesting question by Navneet Chaurasia on Facebook Page. He was asked this question in one of the interview questions for job. Please read the original thread for a complete idea of the conversation. I am presenting the same question here. Puzzle Let us assume there is a single column in the table called Gender. The challenge is to write a single update statement which will flip or swap the value in the column. For example if the value in the gender column is ‘male’ swap it with ‘female’ and if the value is ‘female’ swap it with ‘male’. Here is the quick setup script for the puzzle. USE tempdb GO CREATE TABLE SimpleTable (ID INT, Gender VARCHAR(10)) GO INSERT INTO SimpleTable (ID, Gender) SELECT 1, 'female' UNION ALL SELECT 2, 'male' UNION ALL SELECT 3, 'male' GO SELECT * FROM SimpleTable GO The above query will return following result set. The puzzle was to write a single update column which will generate following result set. There are multiple answers to this simple puzzle. Let me show you three different ways. I am assuming that the column will have either value ‘male’ or ‘female’ only. Method 1: Using CASE Statement I believe this is going to be the most popular solution as we are all familiar with CASE Statement. UPDATE SimpleTable SET Gender = CASE Gender WHEN 'male' THEN 'female' ELSE 'male' END GO SELECT * FROM SimpleTable GO Method 2: Using REPLACE  Function I totally understand it is the not cleanest solution but it will for sure work in giving situation. UPDATE SimpleTable SET Gender = REPLACE(('fe'+Gender),'fefe','') GO SELECT * FROM SimpleTable GO Method 3: Using IIF in SQL Server 2012 If you are using SQL Server 2012 you can use IIF and get the same effect as CASE statement. UPDATE SimpleTable SET Gender = IIF(Gender = 'male', 'female', 'male') GO SELECT * FROM SimpleTable GO You can read my article series on SQL Server 2012 various functions over here. SQL SERVER – Denali – Logical Function – IIF() – A Quick Introduction SQL SERVER – Detecting Leap Year in T-SQL using SQL Server 2012 – IIF, EOMONTH and CONCAT Function Let us clean up. DROP TABLE SimpleTable GO Question to you: I came up with three simple tricks where there is a single UPDATE statement which swaps the values in the column. Do you know any other simple trick? If yes, please post here in the comments. I will pick two random winners from all the valid answers. Winners will get 1) Print Copy of SQL Server Interview Questions and Answers 2) Free Learning Code for Online Video Courses I will announce the winners on coming Monday. Reference:  Pinal Dave (http://blog.SQLAuthority.com) Filed under: CodeProject, PostADay, SQL, SQL Authority, SQL Interview Questions and Answers, SQL Puzzle, SQL Query, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

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  • SQLAuthority News – Monthly list of Puzzles and Solutions on SQLAuthority.com

    - by pinaldave
    This month has been very interesting month for SQLAuthority.com we had multiple and various puzzles which everybody participated and lots of interesting conversation which we have shared. Let us start in latest puzzles and continue going down. There are few answers also posted on facebook as well. SQL SERVER – Puzzle Involving NULL – Resolve – Error – Operand data type void type is invalid for sum operator This puzzle involves NULL and throws an error. The challenge is to resolve the error. There are multiple ways to resolve this error. Readers has contributed various methods. Few of them even have supplied the answer why this error is showing up. NULL are very important part of the database and if one of the column has NULL the result can be totally different than the one expected. SQL SERVER – T-SQL Scripts to Find Maximum between Two Numbers I modified script provided by friend to find greatest number between two number. My script has small bug in it. However, lots of readers have suggested better scripts. Madhivanan has written blog post on the subject over here. SQL SERVER – BI Quiz Hint – Performance Tuning Cubes – Hints This quiz is hosted on my friend Jacob‘s site. I have written many hints how one can tune cubes. Now one can take part here and win exciting prizes. SQL SERVER – Solution – Generating Zero Without using Any Numbers in T-SQL Madhivanan has asked very interesting question on his blog about How to Generate Zero without using Any Numbers in T-SQL. He has demonstrated various methods how one can generate Zero. I asked the same question on blog and got many interesting answers which I have shared. SQL SERVER – Solution – Puzzle – Statistics are not Updated but are Created Once I have to accept that this was most difficult puzzle. In this puzzle I have asked even though settings are correct, why statistics of the tables are not getting updated. In this puzzle one is tested with various concepts 1) Indexes, 2) Statistics, 3) database settings etc. There are multiple ways of solving this puzzles. It was interesting as many took interest but only few got it right. SQL SERVER – Question to You – When to use Function and When to use Stored Procedure This is rather straight forward question and not the typical puzzle. The answers from readers are great however, still there is chance of more detailed answers. SQL SERVER – Selecting Domain from Email Address I wrote on selecting domains from email addresses. Madhivanan makes puzzle out of a simple question. He wrote a follow-up post over here. In his post he writes various way how one can find email addresses from list of domains. Well, this is not a puzzle but amazing Guest Post by Feodor Georgiev who has written on subject Job Interviewing the Right Way (and for the Right Reasons). An article which everyone should read. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, Readers Contribution, Readers Question, SQL, SQL Authority, SQL Puzzle, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

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  • What is the worst programming language you ever worked with? [closed]

    - by Ludwig Weinzierl
    If you have an interesting story to share, please post an answer, but do not abuse this question for bashing a language. We are programmers, and our primary tool is the programming language we use. While there is a lot of discussion about the best one, I'd like to hear your stories about the worst programming languages you ever worked with and I'd like to know exactly what annoyed you. I'd like to collect this stories partly to avoid common pitfalls while designing a language (especially a DSL) and partly to avoid quirky languages in the future in general. This question is not subjective. If a language supports only single character identifiers (see my own answer) this is bad in a non-debatable way. EDIT Some people have raised concerns that this question attracts trolls. Wading through all your answers made one thing clear. The large majority of answers is appropriate, useful and well written. UPDATE 2009-07-01 19:15 GMT The language overview is now complete, covering 103 different languages from 102 answers. I decided to be lax about what counts as a programming language and included anything reasonable. Thank you David for your comments on this. Here are all programming languages covered so far (alphabetical order, linked with answer, new entries in bold): ABAP, all 20th century languages, all drag and drop languages, all proprietary languages, APF, APL (1), AS400, Authorware, Autohotkey, BancaStar, BASIC, Bourne Shell, Brainfuck, C++, Centura Team Developer, Cobol (1), Cold Fusion, Coldfusion, CRM114, Crystal Syntax, CSS, Dataflex 2.3, DB/c DX, dbase II, DCL, Delphi IDE, Doors DXL, DOS batch (1), Excel Macro language, FileMaker, FOCUS, Forth, FORTRAN, FORTRAN 77, HTML, Illustra web blade, Informix 4th Generation Language, Informix Universal Server web blade, INTERCAL, Java, JavaScript (1), JCL (1), karol, LabTalk, Labview, Lingo, LISP, Logo, LOLCODE, LotusScript, m4, Magic II, Makefiles, MapBasic, MaxScript, Meditech Magic, MEL, mIRC Script, MS Access, MUMPS, Oberon, object extensions to C, Objective-C, OPS5, Oz, Perl (1), PHP, PL/SQL, PowerDynamo, PROGRESS 4GL, prova, PS-FOCUS, Python, Regular Expressions, RPG, RPG II, Scheme, ScriptMaker, sendmail.conf, Smalltalk, Smalltalk , SNOBOL, SpeedScript, Sybase PowerBuilder, Symbian C++, System RPL, TCL, TECO, The Visual Software Environment, Tiny praat, TransCAD, troff, uBasic, VB6 (1), VBScript (1), VDF4, Vimscript, Visual Basic (1), Visual C++, Visual Foxpro, VSE, Webspeed, XSLT The answers covering 80386 assembler, VB6 and VBScript have been removed.

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  • Managing/Storing complex application form

    - by mickyjtwin
    I am developing an online application form, which can be of two categories, either domestic/international. Each different type has commong questions, and also specific questions. They are approx 6 pages/steps of questions. The application form can also be saved at the end of each step, and can be completed at a later date. Some questions will vary depending on answers to previous questions, so there are some complex business rules. In terms of storage of results, would it be best to store the answers in and XML field in SQL? What would be the best way to reference a question to an answer. There is no need for the form to be dynamic in rendering questions etc. e.g. <Application id="123" type="Domestic"> <Answers> <EmailAddress>[email protected]</EmailAddress> <HomePhone>555-5555</HomePhone> <Suburb>MySuburb</Suburb> <Guardians> <Guardian type="Mother"> <FirstName>Mom</FirstName> </Guardian> </Guardians> <Answers> </Application>

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  • Realizing program with decision tree logics

    - by Vytas999
    The system realizes a game “Think animal”. Main use case is: 1. System offers user to think about any animal and the system will try to guess it 2. The system starts asking questions from the start of decision tree. Ex., “Question: It has fur?”, and provides possible answers – yes or no. 3. If the user answers Yes, the system proceeds to these steps: a. System tries to guess animal that has that feature, ex. “My guess: Is it bear?” and provides with possible answers – yes or no. b. If the user answer is Yes, the system offers to think off another animal 4. If the user answers is No, the system moves to No node in decision tree and moves to 2 step (and starts from asking from new node). 5. If system runs out of nodes (i.e., empty yes or no node was reached): a. the system announces that it has given up, and ask user to enter: i. What animal he had in mind ii. What is his characteristic feature b. User enters requested data c. The system creates a new node and links it to yes or no of last active node. Where i can get some information and some examples, when implementing decision tree logics in MS SQL Server and C#..? Any information will be usefull. Thanks

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  • named_scope + average is causing the table to be specified more then once in the sql query run on po

    - by hadees
    I have a named scopes like so... named_scope :gender, lambda { |gender| { :joins => {:survey_session => :profile }, :conditions => { :survey_sessions => { :profiles => { :gender => gender } } } } } and when I call it everything works fine. I also have this average method I call... Answer.average(:rating, :include => {:survey_session => :profile}, :group => "profiles.career") which also works fine if I call it like that. However if I were to call it like so... Answer.gender('m').average(:rating, :include => {:survey_session => :profile}, :group => "profiles.career") I get... ActiveRecord::StatementInvalid: PGError: ERROR: table name "profiles" specified more than once : SELECT avg("answers".rating) AS avg_rating, profiles.career AS profiles_career FROM "answers" LEFT OUTER JOIN "survey_sessions" survey_sessions_answers ON "survey_sessions_answers".id = "answers".survey_session_id LEFT OUTER JOIN "profiles" ON "profiles".id = "survey_sessions_answers".profile_id INNER JOIN "survey_sessions" ON "survey_sessions".id = "answers".survey_session_id INNER JOIN "profiles" ON "profiles".id = "survey_sessions".profile_id WHERE ("profiles"."gender" = E'm') GROUP BY profiles.career Which is a little hard to read but says I'm including the table profiles twice. If I were to just remove the include from average it works but it isn't really practical because average is actually being called inside a method which gets passed the scoped. So there is some times gender or average might get called with out each other and if either was missing the profile include it wouldn't work. So either I need to know how to fix this apparent bug in Rails or figure out a way to know what scopes were applied to a ActiveRecord::NamedScope::Scope object so that I could check to see if they have been applied and if not add the include for average.

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  • C# Set combo item with selectedValue

    - by Martijn
    I am dynamically creating a combobox like this: public Control GenerateList(Question question) { // Get a list with answer possibilities List<QuestionAnswer> answers = question.GetAnswers(); // Get a collection of given answers Collection<QuestionnaireAnswer> givenAnswers = question.GetFilledAnswers(); ComboBox cmb = new ComboBox(); cmb.Name = "cmb"; cmb.DataSource = answers; cmb.DisplayMember = "Answer"; cmb.ValueMember = "Id"; // Check an answer is given to the question if (givenAnswers != null && givenAnswers.Count > 0) { cmb.SelectedValue = givenAnswers[0].AnswerId; } cmb.DropDownStyle = ComboBoxStyle.DropDownList; cmb.SelectedIndexChanged += new EventHandler(cmb_SelectedIndexChanged); cmb.Leave += new EventHandler(cmb_Leave); return cmb; } The problem is,when executing cmb.SelectedValue = givenAnswers[0].AnswerId; cmb.SelectedValue is always null. When debugging and I explore answers (the datasource) I see that Id (ValueMember) is exactle the same as AnswerId (in the if statement). Both have the same type (long) and the same value, but SelectedValue stays null. Is there something I don't see?

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  • Difference between two PHP times as years, months and days for PHP version 5.2

    - by Dominor Novus
    Forward: I've scanned through the existing questions/answers on this matter. This is not a duplicitous question; I cannot find a working solution from the accepted answers. The main questions/answers I've reviewed can be found here: How to calculate the difference between two dates using PHP? What I need: A calucalation of the difference between two dates expressed as years, months and days that works with PHP version: 5.2. <?php $current_date = date('d-M-Y'); $future_date = '2012-11-01'; ?> What I've tried: Most answers I find online don't seem to exact in that they don't factor in leap years. This highly rated answer won't work because DateTime-diff() is php 5.3+. This accepted answer results in (i.e. the second block of code aimed at PHP 5.2) results in the following being parsed: Array ( [y] = 25 [m] = 11 [d] = 7 [h] = 3 [i] = 15 [s] = 19 [invert] = 0 [days] = 9473 ) Array ( [y] = 25 [m] = 11 [d] = 7 [h] = 3 [i] = 15 [s] = 19 [invert] = 1 [days] = 9473 ) I can't tell if I've incorrectly applied the code or it's simply a case of me not knowing how to manipulate the array.

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  • Displaying count for current_user 'likes' on a 'question' in questions/show.html.erb view

    - by bgadoci
    I have an application that allows for users to create questions, create answers to questions, and 'like' answers of others. When a current_user lands on the /views/questions/show.html.erb page I am trying to display the total 'likes' for all answers on that question, for the current_user. In my Likes table I am collecting the question_id, site_id and the user_id and I have the appropriate associations set up between user, question, answers and likes. I think I just need to call this information the right way, which I can't seem to figure out. All of the below is taking place in the /views/questions/show.html.erb page. I have tried the following: <% div_for current_user do %> You have liked this question <%= @question.likes.count %> times <% end %> Which returns all the 'likes' for the question but not filtered by current_user You have liked this question <%= current_user.question.likes.count %> times Which gives an error of 'undefined method `question' You have liked this question <%= @question.current_user.likes.count %> times Which gives an error of 'undefined method `current_user' I have tried a couple of other things but they don't make as much sense as the above to me. What am I missing?

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  • How grouping and totaling are done into three tables using JOIN

    - by text
    Here are my tables respondents: field sample value respondentid : 1 age : 2 gender : male survey_questions: id : 1 question : Q1 answer : sample answer answers: respondentid : 1 question : Q1 answer : 1 --id of survey question I want to display all respondents who answered the certain survey, display all answers and total all the answer and group them according to the age bracket. I tried using this query: $sql = "SELECT res.Age, res.Gender, answer.id, answer.respondentid, SUM(CASE WHEN res.Gender='Male' THEN 1 else 0 END) AS males, SUM(CASE WHEN res.Gender='Female' THEN 1 else 0 END) AS females, CASE WHEN res.Age < 1 THEN 'age1' WHEN res.Age BETWEEN 1 AND 4 THEN 'age2' WHEN res.Age BETWEEN 4 AND 9 THEN 'age3' WHEN res.Age BETWEEN 10 AND 14 THEN 'age4' WHEN res.Age BETWEEN 15 AND 19 THEN 'age5' WHEN res.Age BETWEEN 20 AND 29 THEN 'age6' WHEN res.Age BETWEEN 30 AND 39 THEN 'age7' WHEN res.Age BETWEEN 40 AND 49 THEN 'age8' ELSE 'age9' END AS ageband FROM Respondents AS res INNER JOIN Answers as answer ON answer.respondentid=res.respondentid INNER JOIN Questions as question ON answer.Answer=question.id WHERE answer.Question='Q1' GROUP BY ageband ORDER BY res.Age ASC"; I was able to get the data but the listing of all answers are not present. What's wrong with my query. I want to produce something like this: ex: # of Respondents is 3 ages: 2,3 and 6 Question: what are your favorite subjects? Ages 1-4: subject 1: 1 subject 2: 2 subject 3: 2 total respondents for ages 1-4 : 2 Ages 5-10: subject 1: 1 subject 2: 1 subject 3: 0 total respondents for ages 5-10 : 1

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  • Problem with mysql_query() ;Says resource expected .

    - by user364651
    I have this php file. The lines marked as bold are showing up the error :"mysql_query() expecets parameter 2 to be a resources. Well, the similar syntax on the line on which I have commented 'No error??' is working just fine. function checkAnswer($answerEntered,$quesId) { //This functions checks whether answer to question having ques_id = $quesId is satisfied by $answerEntered or not $sql2="SELECT keywords FROM quiz1 WHERE ques_id=$quesId"; **$result2=mysql_query($sql2,$conn);** $keywords=explode(mysql_result($result2,0)); $matches=false; foreach($keywords as $currentKeyword) { if(strcasecmp($currentKeyword,$answerEntered)==0) { $matches=true; } } return $matches; } $sql="SELECT answers FROM user_info WHERE user_id = $_SESSION[user_id]"; $result=mysql_query($sql,$conn); // No error?? $answerText=mysql_result($result,0); //Retrieve answers entered by the user $answerText=str_replace('<','',$answerText); $answerText=str_replace('>',',',$answerText); $answerText=substr($answerText,0,(strlen($answerText)-1)); $answers=explode(",",$answerText); //Get the questions that have been assigned to the user. $sql1="SELECT questions FROM user_info WHERE user_id = $_SESSION[user_id]"; **$result1=mysql_query($sql1,$conn);** $quesIdList=mysql_result($result1,0); $quesIdList=substr($quesIdList,0,(strlen($quesIdList)-1)); $quesIdArray=explode(",",$quesIdList); $reportCard=""; $i=0; foreach($quesIdArray as $currentQuesId) { $answerEnteredByUser=$answers[$i]; if(checkAnswer($answerEnteredByUser,$currentQuesId)) { $reportCard=$reportCard+"1"; } else { $reportCard=$reportCard+"0"; } $i++; } echo $reportCard; ?> Here is the file connect.php. It is working just fine for other PHP documents. <?php $conn= mysql_connect("localhost","root","password"); mysql_select_db("quiz",$conn); ?>

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  • Is this simple XOR encrypted communication absolutely secure?

    - by user3123061
    Say Alice have 4GB USB flash memory and Peter also have 4GB USB flash memory. They once meet and save on both of memories two files named alice_to_peter.key (2GB) and peter_to_alice.key (2GB) which is randomly generated bits. Then they never meet again and communicate electronicaly. Alice also maintains variable called alice_pointer and Peter maintains variable called peter_pointer which is both initially set to zero. Then when Alice needs to send message to Peter they do: encrypted_message_to_peter[n] = message_to_peter[n] XOR alice_to_peter.key[alice_pointer + n] Where n i n-th byte of message. Then alice_pointer is attached at begining of the encrypted message and (alice_pointer + encrypted message) is sent to Peter and then alice_pointer is incremented by length of message (and for maximum security can be used part of key erased) Peter receives encrypted_message, reads alice_pointer stored at beginning of message and do this: message_to_peter[n] = encrypted_message_to_peter[n] XOR alice_to_peter.key[alice_pointer + n] And for maximum security after reading of message also erases used part of key. - EDIT: In fact this step with this simple algorithm (without integrity check and authentication) decreases security, see Paulo Ebermann post below. When Peter needs to send message to Alice they do analogical steps with peter_to_alice.key and with peter_pointer. With this trivial schema they can send for next 50 years each day 2GB / (50 * 365) = cca 115kB of encrypted data in both directions. If they need more data to send, they simple use larger memory for keys for example with today 2TB harddiscs (1TB keys) is possible to exchange next 50years 60MB/day ! (thats practicaly lots of data for example with using compression its more than hour of high quality voice communication) It Seems to me there is no way for attacker to read encrypted message without keys even if they have infinitely fast computer. because even with infinitely fast computer with brute force they get ever possible message that can fit to length of message, but this is astronomical amount of messages and attacker dont know which of them is actual message. I am right? Is this communication schema really absolutely secure? And if its secure, has this communication method its own name? (I mean XOR encryption is well-known, but whats name of this concrete practical application with use large memories at both communication sides for keys? I am humbly expecting that this application has been invented someone before me :-) ) Note: If its absolutely secure then its amazing because with today low cost large memories it is practicaly much cheeper way of secure communication than expensive quantum cryptography and with equivalent security! EDIT: I think it will be more and more practical in future with lower a lower cost of memories. It can solve secure communication forever. Today you have no certainty if someone succesfuly atack to existing ciphers one year later and make its often expensive implementations unsecure. In many cases before comunication exist step where communicating sides meets personaly, thats time to generate large keys. I think its perfect for military communication for example for communication with submarines which can have installed harddrive with large keys and military central can have harddrive for each submarine they have. It can be also practical in everyday life for example for control your bank account because when you create your account you meet with bank etc.

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  • how to add solr to run on startup?

    - by Blankman
    I asked this question before, but I think I got answers that were cron job type answers. I want the solr service to startup if I reboot my computer, and I also want it to run by itself instead of me opening up cmd.exe and running it manually, and then having to close my terminal connection (not log off as that will close it). What options do I have? I am on windows server 2008, IIS7 running a asp.net application that uses solr.

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