Search Results

Search found 43110 results on 1725 pages for 'noob question'.

Page 310/1725 | < Previous Page | 306 307 308 309 310 311 312 313 314 315 316 317  | Next Page >

• Ideally How many connections I have to open ?

  - by ranjith-kumar-u

  Hi All, Recently I attended interview in java, the interviewer asked a question like below: I have a request which go throgh A,B,C modules and response go back throgh A , in module A I need to talk to database and again in module C I need to talk to database, so in this situation how many connections you will open and where do you close those connections? My Answer: I said that in module A I will open a connection and I will close it then and there, then control go to module B then module C, in module C again I will open one more connection and i will close it again. then he asked me again another question I want to open one connection per one request processing, how can i do this?

  Read the article

• How to find the number of inversions in an array ?

  - by Michael

  This is an phone interview question: "Find the number of inversions in an array". I guess they mean O(N*log N) solution since O(N^2) is trivial. I guess it cannot be better than O(N*log N) since sorting is O(N*log N) I have checked a similar question from SO and can summarize the answers as follows: Calculate half the distance the elements should be moved to sort the array : copy the array and sort the copy. For each element of the original array a[i] find it's position j in the sorted copy (binary search) and sum abs(i - j)/2. Modify merge sort : modify merge to count inversions between two sorted arrays (it takes O(N)) and run merge sort with the modified merge. Does it make sense ? Are there other (maybe simpler) solution ? Isn't it too hard for a phone interview ?

  Read the article

• mysql varchar innodb page size limit 8100 bytes

  - by David19801

  Hi, Regarding innodb, someone recently told me: "the varchar content beyond 768 bytes is stored in supplemental 16K pages" This is very interesting. If each varchar will be latin1, which I believe stores as 1byte per letter, would a single varchar(500) (<768 bytes) require an extra i/o as a varchar(1000) (768 bytes) would?? (this question is to find out if all varchars or just big varchars are split into a separate page) Is the 768 limit per varchar or for all varchars in the row added together? (for example, does this get optimized - varchar(300), varchar(300), varchar(300): [where each individual varchar column is below 768 but together they are above 768 characters]? I am confused about if the 768 limit relates to each individual varchar or all varchars in the row totaled (as in the question). Any clarification? EDIT: Removed part about CHARS due to finding out about their limit of 255 max.

  Read the article

• RFC Repository of programming RFC's with ability to direct-link sections or even lines?

  - by Lasse V. Karlsen

  Forgive me if this is the wrong place to ask this, I feel like the question is slightly off-topic even though it is also about programming. I am inputting todo-tasks for my WebDAV-project into my issue tracker, as I read through the relevant RFC's, and it would be nice to be able to add a link in my issue text directly to the relevant text, instead of just a link to the RFC file with a section number in the issue text, and then I have to use the find function to find it. For instance, a link like this: http://ieft.org/rfc2518.txt#1000 <-- line 1000 http://ieft.org/rfc2518.txt#9.8.3 <-- section 9.8.3 Neither of these two works, since they just post the full text files, so my question is this: Does anyone know of hosted versions of the RFC documents that contains such links?

  Read the article

• Determining the order of a list of numbers (possibly without sorting)

  - by Victor Liu

  I have an array of unique integers (e.g. val[i]), in arbitrary order, and I would like to populate another array (ord[i]) with the the sorted indexes of the integers. In other words, val[ord[i]] is in sorted order for increasing i. Right now, I just fill in ord with 0, ..., N, then sort it based on the value array, but I am wondering if we can be more efficient about it since ord is not populated to begin with. This is more of a question out of curiousity; I don't really care about the extra overhead from having to prepopulate a list and then sort it (it's small, I use insertion sort). This may be a silly question with an obvious answer, but I couldn't find anything online.

  Read the article

• Can a pointer ever point to itself?

  - by eSKay

  This question was mentioned here. My doubt is: If a pointer variable has the same address as its value, is it really pointing to itself? For example - in the following piece of code, is a a pointer to itself? #include<stdio.h> int main(){ int* a; int b = (int)&a; a = b; printf("address of a = %d\n", &a); printf(" value of a = %d\n", a); } If a is not a pointer to itself, then the same question poses again: Can a pointer point to itself? Also, how is a self pointing pointer useful?

  Read the article

• MS Access 07 - Q re lookup column vs many-to-many; Q re checkboxes in many-to-many forms

  - by TBinLondon

  Hello, I'm creating a database with Access. This is just a test database, similar to my requirements, so I can get my skills up before creating one for work. I've created a database for a fictional school as this is a good playground and rich data (many students have many subjects have many teachers, etc). Question 1 What is the difference, if any, between using a Lookup column and a many-to-many associate table? Example: I have Tables 'Teacher' and 'Subject'. Many teachers have many subjects. I can, and have, created a table 'Teacher_Subject' and run queries with this. I have then created a lookup column in teachers table with data from subjects. The lookup column seems to take the place of the teacher_subject table. (though the data on relationships is obviously duplicated between lookup table and teacher_subject and may vary). Which one is the 'better' option? Is there a snag with using lookup tables? (I realize that this is a very 'general' question. Links to other resources and answers saying 'that depends...' are appreciated) Question 2 What attracts me to lookup tables is the following: When creating a form for entering subjects for teachers, with lookup I can simply create checkboxes and click a subject for a teacher 'on' or 'off'. Each click on/off creates/removes a record in the lookup column (which replaces teacher_subject). If I use a form from a query from teacher subject with teacher as main form and subject as subform I run into this problem: In the subform I can either select each subject that teacher has in a bombo box, i.e. click, scroll down, select, go to next row, click, scroll down, etc. (takes too long) OR I can create a list box listing all available subjects in each row but allowing me to select only one. (takes up too much space). Is it possible to have a click on/off list box for teacher_subject, creating/removing a record there with each click? Note - I know zero SQL or VB. If the correct answer is "you need to know SQL for this" then that's cool. I just need to know. Thanks!

  Read the article

• How to run Rails 3 application on localhost/<my_port> ?

  - by Misha Moroshko

  To run Rails application on Windows I do: cd < app_dir rails server I see the following: => Booting WEBrick => Rails 3.0.1 application starting in development on http://0.0.0.0:3000 => Call with -d to detach => Ctrl-C to shutdown server [2011-01-12 20:32:07] INFO WEBrick 1.3.1 [2011-01-12 20:32:07] INFO ruby 1.9.2 (2010-08-18) [i386-mingw32] [2011-01-12 20:32:07] INFO WEBrick::HTTPServer#start: pid=5812 port=3000 Question 1 Why port 3000 is selected ? Where is it configured ? Question 2 How could I run 2 applications in parallel ? I guess I need to configure one of them to be on other port (like 3001). How should I do this ?

  Read the article

• Hosting an Access DB

  - by Mitciv

  Hey, So I'm inexperienced in hosting DB's and I've always had the luxury of someone else getting the db setup. I was going to help a friend out with getting a webpage setup, I've got experience in Asp.Net MVC so I'm going with that. They want to setup a search page to query a db and display the results. My question I have is in getting the DB setup and hosted. They currently just have the Access DB on a local computer. There is basically only one table that would need to be queried for the search. What is the best approach to getting this table/db accessible? They would like to keep the main copy of the db on the local machine, so copying the entire db over to the hosted site would be time consuming, could the lone table needed be solely copied to the host? Should I try to convince them to make changes on the hosted db and just make copies of that for their local machines? Any suggestions are welcome, Again I'm a total noob when it comes to hosting databases. Thanks

  Read the article

• Why input elements don't render the value passed in ASP.Net MVC?

  - by MediaSlayer

  This post asks this question but doesn't really give an answer, so I thought I would ask the question differently. I have a page that renders a hidden value from the model: <%=Html.Hidden("myName", model.myValue) %> Since I am passing a value in the value parameter, you would think it would output that value, but it doesn't. The code for rendering input fields has the following: string attemptedValue = (string)htmlHelper.GetModelStateValue(name, typeof(string)); tagBuilder.MergeAttribute("value", attemptedValue ?? ((useViewData) ? htmlHelper.EvalString(name) : valueParameter), isExplicitValue); Basically, if the ModelState (which contains posted values) contains a value for the "name" passed, it will use that value instead of your passed value to the helper method. In my case, I updated the model and my updated value wasn't outputted. If I pass a value to a method, I expect that value to be rendered. Am I missing something in this design or is it just wrong?

  Read the article

• Best way to search for a saturation value in a sorted list

  - by AB Kolan

  A question from Math Battle. This particular question was also asked to me in one of my job interviews. " A monkey has two coconuts. It is fooling around by throwing coconut down from the balconies of M-storey building. The monkey wants to know the lowest floor when coconut is broken. What is the minimal number of attempts needed to establish that fact? " Conditions: if a coconut is broken, you cannot reuse the same. You are left with only with the other coconut Possible approaches/strategies I can think of are Binary break ups & once you find the floor on which the coconut breaks use upcounting from the last found Binary break up lower index. Window/Slices of smaller sets of floors & use binary break up within the Window/Slice (but on the down side this would require a Slicing algorithm of it's own.) Wondering if there are any other way to do this.

  Read the article

• Additional information with widgets in django

  - by fromclouds

  I am displaying a django widget, with which I need to display additional information (something like a tool tip) that is attendant to the widget. I essentially have a widget that asks a random question, which is self contained. {{ form.fieldname }} displays the full widget which looks something like (à la the widget's render method): <label for="id_answer">Question:</label> <input type="hidden" name="question_id" value="n" /> <span class="prompt">What is the air-speed velocity of an unladen swallow?</span> <input type="text" name="answer" /> What I'm essentially asking is, is there a way to break out the prompt, so that I can lay the widget out piecemeal? I would like to lay it out not with a call to {{ form.fieldname }} as above, but like: {{ form.fieldname.label }} {{ form.fieldname.prompt }} {{ form.fieldname }} Does anyone know how to do this?

  Read the article

• Can I add and remove elements of enumeration at runtime in Java

  - by Brabster

  It is possible to add and remove elements from an enum in Java at runtime? For example, could I read in the labels and constructor arguments of an enum from a file? @saua, it's just a question of whether it can be done out of interest really. I was hoping there'd be some neat way of altering the running bytecode, maybe using BCEL or something. I've also followed up with this question because I realised I wasn't totally sure when an enum should be used. I'm pretty convinced that the right answer would be to use a collection that ensured uniqueness instead of an enum if I want to be able to alter the contents safely at runtime.

  Read the article

• Can a constructor in java can be private?

  - by Rajesh

  If the answer for my question is yes, then what is the use of having a private constructor.

  Read the article

• Are there any platforms where using structure copy on an fd_set (for select() or pselect()) causes p

  - by Jonathan Leffler

  The select() and pselect() system calls modify their arguments (the 'struct fd_set *' arguments), so the input value tells the system which file descriptors to check and the return values tell the programmer which file descriptors are currently usable. If you are going to call them repeatedly for the same set of file descriptors, you need to ensure that you have a fresh copy of the descriptors for each call. The obvious way to do that is to use a structure copy: struct fd_set ref_set_rd; struct fd_set ref_set_wr; struct fd_set ref_set_er; ... ...code to set the reference fd_set_xx values... ... while (!done) { struct fd_set act_set_rd = ref_set_rd; struct fd_set act_set_wr = ref_set_wr; struct fd_set act_set_er = ref_set_er; int bits_set = select(max_fd, &act_set_rd, &act_set_wr, &act_set_er, &timeout); if (bits_set > 0) { ...process the output values of act_set_xx... } } My question: Are there any platforms where it is not safe to do a structure copy of the struct fd_set values as shown? I'm concerned lest there be hidden memory allocation or anything unexpected like that. (There are macros/functions FD_SET(), FD_CLR(), FD_ZERO() and FD_ISSET() to mask the internals from the application.) I can see that MacOS X (Darwin) is safe; other BSD-based systems are likely to be safe, therefore. You can help by documenting other systems that you know are safe in your answers. (I do have minor concerns about how well the struct fd_set would work with more than 8192 open file descriptors - the default maximum number of open files is only 256, but the maximum number is 'unlimited'. Also, since the structures are 1 KB, the copying code is not dreadfully efficient, but then running through a list of file descriptors to recreate the input mask on each cycle is not necessarily efficient either. Maybe you can't do select() when you have that many file descriptors open, though that is when you are most likely to need the functionality.) There's a related SO question - asking about 'poll() vs select()' which addresses a different set of issues from this question.

  Read the article

• What is a good way of coding a file processing program, which accepts multisource data in Java

  - by jjepsuomi

  I'm making a data prosessing system, which currently is using csv-data as input and output form. In the future I might want to add support for example database-, xml-, etc. typed input and output forms. How should I desing my program so that it would be easy to add support for new type of data sources? Should simply make for example an abstract data class (which would contain the basic file prosessing methods) and then inherit this class for database, xml, etc. cases? Hope my question is clear =) In other words my question is: "How to desing a file prosessing system, which can be easily updated to accept input data from different sources (database, XML, Excel, etc.)".

  Read the article

• copy C'tor with operator= | C++

  - by user2266935

  I've got this code here: class DerivedClass : public BaseClass { SomeClass* a1; Someclass* a2; public: //constructors go here ~DerivedClass() { delete a1; delete a2;} // other functions go here .... }; My first question is as follows: Can I write an "operator=" to "DerivedClass" ? (if your answer is yes, could you show me how?) My second question is: If the answer to the above is yes, could you show me how to make an "copy c'tor" using the "operator=" that you wrote beforehand (if that is even possible)? Your help would be much appreciated !

  Read the article

• How long does a MailItem.Property[myProperty] live?

  - by Darien Ford

  I'm writing a TransportAgent for Exchange and want to tag a MailItem with some identifying information. The MailItem class seems to have this functionality with the MailItem.Properties property; however, my question is to the length of time an entry would remain available. e.g. e.MailItem.Properties.Add(new KeyValuePair<string,object>("MyKey", "myValue")); After this MailItem is delivered to the correct mailbox, if someone were to reply to the email, would the newly created reply retain that set value? I think while writing this question out I have answered it for myself (which rationally would be no) but any practical experience and insight would be appreciated.

  Read the article

• How do I output an individual character when using char *[] = "something"

  - by Matt

  I've been playing with pointers to better understand them and I came across something I think I should be able to do, but can't sort out how. The code below works fine - I can output "a", "dog", "socks", and "pants" - but what if I wanted to just output the 'o' from "socks"? How would I do that? char *mars[4] = { "a", "dog", "sock", "pants" }; for ( int counter = 0; counter < 4; counter++ ) { cout << mars[ counter ]; } Please forgive me if the question is answered somewhere - there are 30+ pages of C++ pointer related question, and I spent about 90 minutes looking through them, as well as reading various (very informative) articles, before deciding to ask.

  Read the article

• Codesample with bufferoverflow (gets method). Why does it not behave as expected?

  - by citronas

  This an extract from an c program that should demonstrate a bufferoverflow. void foo() { char arr[8]; printf(" enter bla bla bla"); gets(arr); printf(" you entered %s\n", arr); } The question was "How many input chars can a user maximal enter without a creating a buffer overflow" My initial answer was 8, because the char-array is 8 bytes long. Although I was pretty certain my answer was correct, I tried a higher amount of chars, and found that the limit of chars that I can enter, before I get a segmentation fault is 11. (Im running this on A VirtualBox Ubuntu) So my question is: Why is it possible to enter 11 chars into that 8 byte array?

  Read the article

• Why is writing a compiler in a functional language easier?

  - by wvd

  Hello all, I've been thinking of this question very long, but really couldn't find the answer on Google as well a similar question on Stackoverflow. If there is a duplicate, I'm sorry for that. A lot of people seem to say that writing compilers and other language tools in functional languages such as OCaml and Haskell is much more efficient and easier then writing them in imperative languages. Is this true? And if so -- why is it so efficient and easy to write them in functional languages instead of in an imperative language, like C? Also -- isn't a language tool in a functional language slower then in some low-level language like C? Thanks in advance, William v. Doorn

  Read the article

• When to use <strong> and when to use <b>?

  - by metal-gear-solid

  When to use <strong> and when to use <b> or other ways to give look of bold? strong has semantic value ( and useful for screen reader while b is presentation (and even valid in HTML 5). my question is not what is the difference between strong and b. The question is when to use semantic tag and when to use just to make text bold Should I always use <strong> if client's content files (MS word files) has some words bold in content paragraphs? How can we know when client want to give emphasis to text and when he just want to make text bold for presentation/aesthetic purpose? If it's client job to tell us, then how to explain this scenario to client to give us clear info on "when he just want to make text bold for presentation/aesthetic purpose" ?

  Read the article

• What are the exact versions of stuff you have to install in order to be able to step-debug a Scala p

  - by Alex R

  How do YOU debug a Scala program? I mean YOU as in the person posting the Answer :) Please answer only from personal experience, not from stuff you've heard or read on the Internet. You should not believe everything you read on the Internet, especially tales of complex open-source software configurations that actually work :-) The are many Java tools which claim to support Scala in some way or another, but I have so far struck out in trying to get any one of them to actually let me set a breakpoint in Scala code and step through it. These are big, major open-source IDEs I'm talking about here. The main problem in getting a debugger to work seems to be the "version hell" with fast-changing IDEs, Plug-Ins, JDKs, and the Scala language itself. Hence, the more detailed re-statement of the question is appropriate: What is the exact version number of the IDE, Plug-In, JDK, Scala, and even Operating System, that you are successfully using? My question is related to this one, but wider in scope: http://stackoverflow.com/questions/2272705/how-to-debug-scala-code-when-outside-of-an-ide Thanks

  Read the article

• List of dependency jar files in Maven

  - by Sindri Traustason

  Using Maven 2, is there a way I can list out the jar dependencies as just the file names? mvn dependency:build-classpath can list the jar files, but that will include the full path to their location in my local repository. What I need is essentially just a list of the file names (or the file names that the copy-dependencies goal copied). So the list I need would be something like activation-1.1.jar,antlr-2.7.6.jar,aopalliance-1.0.jar etc... ideally as a maven property, but I guess, a file such as build-classpath can generate will do. What I am trying to achieve is writing a Bundle-ClassPath to an otherwise manually maintained MANIFEST.MF file for a OSGi bundle. (You shouldn't need to understand this bit to answer the question.) To clarify: The question is not about how to write manifest headers into the MANIFEST.MF file in a jar (that is easily googleble). I am asking about how to get the data I want to write, namely the list shown above.

  Read the article

• Why does std::map operator[] create an object if the key doesn't exist?

  - by n1ck

  Hi, I'm pretty sure I already saw this question somewhere (comp.lang.c++? Google doesn't seem to find it there either) but a quick search here doesn't seem to find it so here it is: Why does the std::map operator[] create an object if the key doesn't exist? I don't know but for me this seems counter-intuitive if you compare to most other operator[] (like std::vector) where if you use it you must be sure that the index exists. I'm wondering what's the rationale for implementing this behavior in std::map. Like I said wouldn't it be more intuitive to act more like an index in a vector and crash (well undefined behavior I guess) when accessed with an invalid key? Refining my question after seeing the answers: Ok so far I got a lot of answers saying basically it's cheap so why not or things similar. I totally agree with that but why not use a dedicated function for that (I think one of the comment said that in java there is no operator[] and the function is called put)? My point is why doesn't map operator[] work like a vector? If I use operator[] on an out of range index on a vector I wouldn't like it to insert an element even if it was cheap because that probably mean an error in my code. My point is why isn't it the same thing with map. I mean, for me, using operator[] on a map would mean: i know this key already exist (for whatever reason, i just inserted it, I have redundancy somewhere, whatever). I think it would be more intuitive that way. That said what are the advantage of doing the current behavior with operator[] (and only for that, I agree that a function with the current behavior should be there, just not operator[])? Maybe it give clearer code that way? I don't know. Another answer was that it already existed that way so why not keep it but then, probably when they (the ones before stl) choose to implement it that way they found it provided an advantage or something? So my question is basically: why choose to implement it that way, meaning a somewhat lack of consistency with other operator[]. What benefit do it give? Thanks

  Read the article

< Previous Page | 306 307 308 309 310 311 312 313 314 315 316 317  | Next Page >