Search Results

Search found 102826 results on 4114 pages for 'question about the problem'.

Page 59/4114 | < Previous Page | 55 56 57 58 59 60 61 62 63 64 65 66  | Next Page >

  • Database Design Question: GUID + Natural Numbers

    - by Alan
    For a database I'm building, I've decided to use natural numbers as the primary key. I'm aware of the advantages that GUID's allow, but looking at the data, the bulk of row's data were GUID keys. I want to generate XML records from the database data, and one problem with natural numbers is that I don't want to expose my database key's to the outside world, and allow users to guess "keys." I believe GUID's solve this problem. So, I think the solution is to generate a sparse, unique iD derived from the natural ID (hopefully it would be 2-way), or just add an extra column in the database and store a guid (or some other multibyte id) The derived value is nicer because there is no storage penalty, but it would be easier to reverse and guess compared to a GUID. I'm (buy) curious as to what others on SO have done, and what insights they have.

    Read the article

  • PHP Regex Question

    - by oyerli
    Hi, I am developing an application using PHP but I am new to regular expressions, I could not find a solution to my problem. I want to replace all occurences of #word with a link, i have written a preg_match for this: $text=preg_replace('~#([\p{L}|\p{N}]+)~u', '<a href="/?aranan=$1">#$1</a>', $text); The problem is, this regular expression also matches the html character codes like &#039; and gives corrupt output. I need to exclude the words starting with &# but i do not know how to do that using regular expressions. Thanks for your help.

    Read the article

  • HTML5 Canvas compositing question (source-in)

    - by Alex Ciarlillo
    I am trying to recreate a page flipping type animation in HTML5 using canvas. The animation is based on ideas from here: hxxp://oreilly.com/javascript/archive/flashhacks.html but thats not really important. The problem I am having is that using the 'source-in' composite operation is not giving me the results I expect and would like clarification as to why. Here is the example: (i think it can only be viewed in chrome, not working in FF 3.6) http://acpound.fylez.com/test/example.html The black rectangle is supposed to act as a 'mask' for the page being turned over. All I want to see is the turning page in the areas where it overlaps the mask. The problem is the entire black rectangle is drawn, not just the area where they overlap. The source is all on the page. I know HTML5 isn't really being used yet, I'm just experimenting for my personal site and curiosity. Any ideas would be greatly appreciated.

    Read the article

  • SQL Design Question regarding schema and if Name value pair is the best solution

    - by Aur
    I am having a small problem trying to decide on database schema for a current project. I am by no means a DBA. The application parses through a file based on user input and enters that data in the database. The number of fields that can be parsed is between 1 and 42 at the current moment. The current design of the database is entirely flat with there being 42 columns; some have repeated columns such as address1, address2, address3, etc... This says that I should normalize the data. However, data integrity is not needed at this moment and the way the data is shaped I'm looking at several joins. Not a bad thing but the data is still in a 1 to 1 relationship and I still see a lot of empty fields per row. So my concerns are that this does not allow the database or the application to be very extendable. If they want to add more fields to be parsed (which they do) than I'd need to create another table and add another foreign key to the linking table. The third option is I have a table where the fields are defined and a table for each record. So what I was thinking is to make a table that stores the value and then links to those two tables. The problem is I can picture the size of that table growing large depending on the input size. If someone gives me a file with 300,000 records than 300,000 x 40 = 12 million so I have some reservations. However I think if I get to that point than I should be happy it is being used. This option also allows for more custom displaying of information albeit a bit more work but little rework even if you add more fields. So the problem boils down to: 1. Current design is a flat file which makes extending it hard and it is not normalized. 2. Normalize the tables although no real benefits for the moment but requirements change. 3. Normalize it down into the name value pair and hope size doesn't hurt. There are a large number of inserts, updates, and selects against that table. So performance is a worry but I believe the saying is design now, performance testing later? I'm probably just missing something practical so any comments would be appreciated even if it’s a quick sanity check. Thank you for your time.

    Read the article

  • A question about making a C# class persistant during a file load

    - by Adam
    Apologies for the indescriptive title, however it's the best I could think of for the moment. Basically, I've written a singleton class that loads files into a database. These files are typically large, and take hours to process. What I am looking for is to make a method where I can have this class running, and be able to call methods from within it, even if it's calling class is shut down. The singleton class is simple. It starts a thread that loads the file into the database, while having methods to report on the current status. In a nutshell it's al little like this: public sealed class BulkFileLoader { static BulkFileLoader instance = null; int currentCount = 0; BulkFileLoader() public static BulkFileLoader Instance { // Instanciate the instance class if necessary, and return it } public void Go() { // kick of 'ProcessFile' thread } public void GetCurrentCount() { return currentCount; } private void ProcessFile() { while (more rows in the import file) { // insert the row into the database currentCount++; } } } The idea is that you can get an instance of BulkFileLoader to execute, which will process a file to load, while at any time you can get realtime updates on the number of rows its done so far using the GetCurrentCount() method. This works fine, except the calling class needs to stay open the whole time for the processing to continue. As soon as I stop the calling class, the BulkFileLoader instance is removed, and it stops processing the file. What I am after is a solution where it will continue to run independently, regardless of what happens to the calling class. I then tried another approach. I created a simple console application that kicks off the BulkFileLoader, and then wrapped it around as a process. This fixes one problem, since now when I kick off the process, the file will continue to load even if I close the class that called the process. However, now the problem I have is that cannot get updates on the current count, since if I try and get the instance of BulkFileLoader (which, as mentioned before is a singleton), it creates a new instance, rather than returning the instance that is currently in the executing process. It would appear that singletons don't extend into the scope of other processes running on the machine. In the end, I want to be able to kick off the BulkFileLoader, and at any time be able to find out how many rows it's processed. However, that is even if I close the application I used to start it. Can anyone see a solution to my problem?

    Read the article

  • C++ Inheritance Question

    - by shaz
    I have a base class MessageHandler and 2 derived classes, MessageHandler_CB and MessageHandler_DQ. The derived classes redefine the handleMessage(...) method. MH_DQ processes a message and puts the result in a deque while MH_CB processes the message and then executes a callback function. The base class has a static callback function that I pass along with a this pointer to a library which calls the static callback when a new message is available for processing. My problem comes when I am in the static callback with a void * pointing to either a MH_DQ or a MH_CB. If I cast it to the base class the empty MessageHandler::handleMessage(...) method is called, rather than the version in the appropriate derived class. What is the best way to address this situation from a design perspective and/or what language features might help me to implement a solution to my problem? Thanks in advance!

    Read the article

  • weird swing heavyweight object lightweight objects problem

    - by Yoav Schwartz
    Hello, We have a problem in our swing based application since we've upgraded our java version from 6u5 to 6u18 (The application runs over WinXP). Our application contains a Canvas object which resides in a JFrame. The application draws things on the canvas. Every time we drag a lightweight swing object (popup or another frame) over the canvas, it has a refresh problem. It blinks - becomes black. The problem only resolves after we move the swing component away from the canvas and click on it again. We think this problem is related to the fact the the canvas is a heavyweight object. And we know there were changes done in the new versions of java on the mixing of heavyweight and lightweight objects issue. Some more details: 1) Our problem reproduces in java 6u14 and 6u16. 2) Everything works fine in java 6u5. Another strange thing: We have 2 types of stations running our application. The first type has a ATI FireGL7100 PCI-E graphics card. The second type has a Matrox G450 PCI graphic card. The problem does not reproduce on the Matrox based station in any java version. One more thing: http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6829858 - looks similar to our problem. Is our problem familiar? Do you have any suggestions (workarounds, ideas how the difference in graphics cards is connected to this problem) Hope I was clear enough, Yoav

    Read the article

  • Can the Diamond Problem be really solved?

    - by Mecki
    A typical problem in OO programming is the diamond problem. I have parent class A with two sub-classes B and C. A has an abstract method, B and C implement it. Now I have a sub-class D, that inherits of B and C. The diamond problem is now, what implementation shall D use, the one of B or the one of C? People claim Java knows no diamond problem. I can only have multiple inheritance with interfaces and since they have no implementation, I have no diamond problem. Is this really true? I don't think so. See below: [removed vehicle example] Is a diamond problem always the cause of bad class design and something neither programmer nor compiler needs to solve, because it shouldn't exist in the first place? Update: Maybe my example was poorly chosen. See this image Of course you can make Person virtual in C++ and thus you will only have one instance of person in memory, but the real problem persists IMHO. How would you implement getDepartment() for GradTeachingFellow? Consider, he might be student in one department and teach in another one. So you can either return one department or the other one; there is no perfect solution to the problem and the fact that no implementation might be inherited (e.g. Student and Teacher could both be interfaces) doesn't seem to solve the problem to me.

    Read the article

  • UML assignment question

    - by waitinforatrain
    Hi guys, Sorry, I know this is a very lame question to ask and not of any use to anyone else. I have an assignment in UML due tomorrow and I don't even know the basics (all-nighter ahead!). I'm not looking for a walkthrough, I simply want your opinion on something. The assignment is as follows (you only need to skim over it!): ============= Gourmet Surprise (GS) is a small catering firm with five employees. During a typical weekend, GS caters fifteen events with twenty to fifty people each. The business has grown rapidly over the past year and the owner wants to install a new computer system for managing the ordering and buying process. GS has a set of ten standard menus. When potential customers call, the receptionist describes the menus to them. If the customer decides to book an event (dinner, lunch, picnic, finger food etc.), the receptionist records the customer information (e.g., name, address, phone number, etc.) and the information about the event (e.g., place, date, time, which one of the standard menus, total price) on a contract. The customer is then faxed a copy of the contract and must sign and return it along with a deposit (often a credit card or by check) before the event is officially booked. The remaining money is collected when the catering is delivered. Sometimes, the customer wants something special (e.g., birthday cake). In this case, the receptionist takes the information and gives it to the owner who determines the cost; the receptionist then calls the customer back with the price information. Sometimes the customer accepts the price, other times, the customer requests some changes that have to go back to the owner for a new cost estimate. Each week, the owner looks through the events scheduled for that weekend and orders the supplies (e.g., plates) and food (e.g., bread, chicken) needed to make them. The owner would like to use the system for marketing as well. It should be able to track how customers learned about GS, and identify repeat customers, so that GS can mail special offers to them. The owner also wants to track the events on which GS sent a contract, but the customer never signed the contract and actually booked a GS. Exercise: Create an activity diagram and a use case model (complete with a set of detail use case descriptions) for the above system. Produce an initial domain model (class diagram) based on these descriptions. Elaborate the use cases into sequence diagrams, and include any state diagrams necessary. Finally use the information from these dynamic models to expand the domain model into a full application model. ============= In your opinion, do you think this question is asking me to come up with a package for an online ordering system to replace the system described above, or to create UML diagrams that facilitate the existing telephone-based system?

    Read the article

  • write c++ in latex, noob latex question

    - by voodoomsr
    maybe is a noob question but i can't find the solution in the web, i need to write C++ in Latex. I write C$++$ but the result is like crap, the signs are too big and there is too much space between C and the first plus sign. Previously i needed to write the sharp symbol for C#....c$\sharp$ it also looks like crap but with a escape character it looks nice, for the plus sign i can't do the same.

    Read the article

  • jquery animate question

    - by user313271
    jquery code $(function(){ $('#switcher1').click(function(){ $(this).stop().animate({left:'35px'},800); }); }); Hey everybody, this code slides #switcher1 at 35px to the right. I have question, how i can make that #switcher1 on one more click slides back to the original position ?

    Read the article

  • Very Simple Regex Question

    - by Sunil
    Hello sir I have a very simple regex question suppose I have 2 condition 1 url =http://www.abc.com/cde/def 2 url =https://www.abc.com/sadfl/dsaf and how can I extract the baseUrl using regex. sample output 1 http://www.abc.com 2 https://www.abc.com Thanks

    Read the article

  • Relational database question with php.

    - by Oliver Bayes-Shelton
    Hi, Not really a coding question more a little help with my idea of a Relational database. If I have 3 tables in a SQL database. In my php script I basically query the companies which are in industry "a" and then insert a row into a separate table with their details such as companyId , companyName etc is that a type of Relational database ? I have explained it in a simple way so we don't get confused what I am trying to say.

    Read the article

  • SHA1 hash question

    - by phenevo
    Hi, I have this method to hash a string: byte[] buffer = enc.GetBytes(text); SHA1CryptoServiceProvider cryptoTransformSHA1 = new SHA1CryptoServiceProvider(); string hash = BitConverter.ToString( cryptoTransformSHA1.ComputeHash(buffer)).Replace("-", ""); return hash; My question is: Is the resulting hash always the same for the same string? I hashed a string a couple of days ago and it seems that it now resulted in another hash, but i'm not sure.

    Read the article

  • Beginner SEO question on urlrewrite rules

    - by Charlie
    I just starting reading about SEO and realized that I should change my "GET" queries to / separated keywords for SEO purposes. Here's my question: I have a multi-select checkbox on my form, so my query string would be: http://www.domainname.com/searchitem.html?cat[]=A&cat[]=B&cat[]=C&param1=p1&param2=p2 Whats the convention for handling this kind of queries? changing it to search/catA/catB/catC/p1/p2 doesn't seem right to me but i don't know what else to do Thanks

    Read the article

  • Question on Viewstate

    - by ScG
    I have a couple of pages that are bulky due to the viewstate. I have following question: is there any tool that can track viewstate of individual control on page and tell me which control is taking maxm viewstate also can i know which controls viewstate is not being used and disable it?

    Read the article

  • Java focus question

    - by Albinoswordfish
    This may be a silly question I don't know. Is there a way to remove the highlighter to represent focus in a Java GUI? For example when you click on a button the text will have a slight rectangle around the text. Thank you

    Read the article

  • Regular expressions and the question mark

    - by James P.
    I'm having trouble finding a regular expression that matches the following String. Korben;http://feeds.feedburner.com/KorbensBlog-UpgradeYourMind?format=xml;1 One problem is escaping the question mark. Java's pattern matcher doesn't seem to accept \? as a valid escape sequence but it also fails to work with the tester at myregexp.com. Here's what I have so far: ([a-zA-Z0-9])+;http://([a-zA-Z0-9./-]+);[0-9]+ Any suggestions?

    Read the article

  • hibernate column uniqueness question

    - by Seth
    I'm still in the process of learning hibernate/hql and I have a question that's half best practices question/half sanity check. Let's say I have a class A: @Entity public class A { @Id @GeneratedValue(strategy=GenerationType.AUTO) private Long id; @Column(unique=true) private String name = ""; //getters, setters, etc. omitted for brevity } I want to enforce that every instance of A that gets saved has a unique name (hence the @Column annotation), but I also want to be able to handle the case where there's already an A instance saved that has that name. I see two ways of doing this: 1) I can catch the org.hibernate.exception.ConstraintViolationException that could be thrown during the session.saveOrUpdate() call and try to handle it. 2) I can query for existing instances of A that already have that name in the DAO before calling session.saveOrUpdate(). Right now I'm leaning towards approach 2, because in approach 1 I don't know how to programmatically figure out which constraint was violated (there are a couple of other unique members in A). Right now my DAO.save() code looks roughly like this: public void save(A a) throws DataAccessException, NonUniqueNameException { Session session = sessionFactory.getCurrentSession(); try { session.beginTransaction(); Query query = null; //if id isn't null, make sure we don't count this object as a duplicate if(obj.getId() == null) { query = session.createQuery("select count(a) from A a where a.name = :name").setParameter("name", obj.getName()); } else { query = session.createQuery("select count(a) from A a where a.name = :name " + "and a.id != :id").setParameter("name", obj.getName()).setParameter("name", obj.getName()); } Long numNameDuplicates = (Long)query.uniqueResult(); if(numNameDuplicates > 0) throw new NonUniqueNameException(); session.saveOrUpdate(a); session.getTransaction().commit(); } catch(RuntimeException e) { session.getTransaction().rollback(); throw new DataAccessException(e); //my own class } } Am I going about this in the right way? Can hibernate tell me programmatically (i.e. not as an error string) which value is violating the uniqueness constraint? By separating the query from the commit, am I inviting thread-safety errors, or am I safe? How is this usually done? Thanks!

    Read the article

  • NASM and a question about ADC - ASM 8086

    - by Tal
    Hello,I study assembly on High-school and I would like to try to make assembly programs at home. I downloaded NASM but I don't understand how to run the .s files with it - if you can write a simple way here to run it I'd glad :-) and in addition I have a question: when I use ADC for exmaple: AL = 01 and BL = 02, and CF = 1, when I make this: ADC AL,BL Will AL be 3 or 4? (with the CF addition or without?) Thank you!!

    Read the article

  • Simple question on ASM 8086

    - by Tal
    Hello ,I'm studying ASM 8086 at high school and I have this question: For example I have this number ABCD(hex), how is it stored on the memory? Does the AB go for example to memory address 01 and the CD goes to address 02? Thank you :-)

    Read the article

< Previous Page | 55 56 57 58 59 60 61 62 63 64 65 66  | Next Page >