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  • Is there a standard SQL Table design for overriding 'big picture' default values with lower level de

    - by RichardHowells
    Here's an example. Suppose we are trying to calculate a service charge. Say sales in the USA attract a 10 dollar charge, sales in the UK attract a 20 dollar charge So far it's easy - we are starting to imagine a table that lists charges by country. Now lets assume that Alaska and Hawaii are treated as special cases they are both 15 dollars That suggests a table with states, Alaska and Hawaii are charged at 15, but presumably we need 48 (redundant) rows all saying 10. This gives us a maintainance problem, our user only wants to type 10 once NOT 48 times. It does not sit well with the UK either. The UK does not have states. Suppose we throw in another couple of cross cutting rules. If you order by phone there is a 10% supplement on the charge. If you order via the web there is a 10% discount. But for some reason best known to the owners of the business the web/phone supplement/discount are not applied in Hawaii. It seems to me that this is quite a common kind of problem and there is probably a well known arrangement of tables to store the data. Most cases get handled by broad brush answers, but there are some very detailed low level variations that give rise to a huge number of theoretical combinations, most of which are not used.

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  • Most efficient way to make an activity log

    - by Nathan
    I am making a "recent activity" tab to profiles on my site and I also am going to have a log for moderators to see everything that happens on the site. This would require making an activity log of some sort. I just don't know what would be better. I have 2 options: Make a table called "activity" and then every time someone does something, add a record to it with the type of action, user id, timestamp, etc. Problem: table could get very long. Join all 3 tables (questions, answers, answer_comments) and then somehow show all these on the page in the order in which the action was taken. Problem: this would be extremely hard because I have no clue how I could make it say "John commented on an answer on Question Title Here" by just joining 3 tables. Does anyone know of a better way of making an activity log in this situation? I am using PHP and MySQL. If this is either too inefficient or hard I will probably just forget the Recent Activity tab on profiles but I still need an activity log for moderators. Here's some SQL that I started making for option 2, but this would not work because there is no way of detecting whether the action is a comment, question, or answer when I echo the info in a while loop: SELECT q.*, a.*, ac.* FROM questions q JOIN answers a ON a.questionid = q.qid JOIN answer_comments ac ON c.answerid = a.ans_id WHERE q.user = $userid AND a.userid = $userid AND ac.userid = $userid ORDER BY q.created DESC, a.created DESC, ac.created DESC Thanks in advance for any help!

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  • Creating webpage on form submit?

    - by Joachim Mcdonald
    How is it possible to allow a user to create a webpage containing some html, based on their entries in a form? ie. I would want them to be able to input a name and when the button is clicked, a webpage called that name would be created. I imagine that this must be possible in php, but what functions/code would I be using? Thank you!

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  • How can I map a String to a function in Java?

    - by Bears will eat you
    Currently, I have a bunch of Java classes that implement a Processor interface, meaning they all have a processRequest(String key) method. The idea is that each class has a few (say, <10) member Strings, and each of those maps to a method in that class via the processRequest method, like so: class FooProcessor implements Processor { String key1 = "abc"; String key2 = "def"; String key3 = "ghi"; // and so on... String processRequest(String key) { String toReturn = null; if (key1.equals(key)) toReturn = method1(); else if (key2.equals(key)) toReturn = method2(); else if (key3.equals(key)) toReturn = method3(); // and so on... return toReturn; } String method1() { // do stuff } String method2() { // do other stuff } String method3() { // do other other stuff } // and so on... } You get the idea. This was working fine for me, but now I need a runtime-accessible mapping from key to function; not every function actually returns a String (some return void) and I need to dynamically access the return type (using reflection) of each function in each class that there's a key for. I already have a manager that knows about all the keys, but not the mapping from key to function. My first instinct was to replace this mapping using if-else statements with a Map<String, Function>, like I could do in Javascript. But, Java doesn't support first-class functions so I'm out of luck there. I could probably dig up a third-party library that lets me work with first-class functions, but I haven't seen any yet, and I doubt that I need an entire new library. I also thought of putting these String keys into an array and using reflection to invoke the methods by name, but I see two downsides to this method: My keys would have to be named the same as the method - or be named in a particular, consistent way so that it's easy to map them to the method name. This seems WAY slower than the if-else statements I have right now. Efficiency is something of a concern because these methods will tend to get called pretty frequently, and I want to minimize unnecessary overhead. TL; DR: I'm looking for a clean, minimal-overhead way to map a String to some sort of a Function object that I can invoke and call (something like) getReturnType() on. I don't especially mind using a 3rd-party library if it really fits my needs. I also don't mind using reflection, though I would strongly prefer to avoid using reflection every single time I do a method lookup - maybe using some caching strategy that combines the Map with reflection. Thoughts on a good way to get what I want? Cheers!

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  • Can IDL evaluate strings as code?

    - by Carthage
    Is there any functionality in IDL that will allow it to evaluate a a string as code? Or, failing that, is there a nice, dynamic way of including /KEYWORD in functions? For example, if I wanted to ask them for what type of map projection the user wants, is there a way to do it nicely, without large if/case statements for the /Projection_Type keyword it needs? With even a small number of user options, the combinations would cause if/case statements to get out of hand very quickly to handle all the possible options.

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  • question about permutation problem

    - by davit-datuashvili
    i have posted similar problem here http://stackoverflow.com/questions/2920315/permutation-of-array but i want following we know that with length n there is n! possible permutation from which one such that all element are in order they are in sorted variant so i want break permutation when array is in order and print result but something is wrong i think that problem is repeated of permutation here is my code import java.util.*; public class permut{ public static Random r=new Random(); public static void display(int a[],int n){ for (int i=0;i<n;i++){ System.out.println(a[i]); } } public static void Permut(int a[],int n){ int j=0; int k=0; while (j<fact(n)){ int s=r.nextInt(n); for (int i=0;i<n;i++){ k=a[i]; a[i]=a[s]; a[s]=k; } j++; if (sorted(a,n)) display(a,n); break; } } public static void main(String[]args){ int a[]=new int[]{3,4,1,2}; int n=a.length; Permut(a,n); } public static int fact(int n){ if (n==0 || (n==1) ) return 1; return n*fact(n-1); } public static boolean sorted(int a[],int n ){ boolean flag=false; for (int i=0;i<n-1;i++){ if (a[i]<a[i+1]){ flag=true; } else{ flag=false; } } return flag; } } can anybody help me? result is nothing

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  • LInux C++: how do profile time wasted due to cache misses?

    - by anon
    I know that I can use gprof to benchmark my code. However, I have this problem -- I have a smart pointer that has an extra level of indirection (think of it as a proxy object). As a result, I have this extra layer that effects pretty much all functions, and screws with caching. Is there a way to measure the time my CPU wastes due to cache misses? Thanks!

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  • How to access CWebBrowser class instance (defined in a protected class) in a different class? C++

    - by extintor
    I have been playing with this webbrowser control example I got it working and added some timers using ON_WM_TIMER. Now I would like to access the m_Browser (CWebBrowser class instance) defined inside the protected CMyBrowserView class into a different class. (for example CMyBrowserApp in the code sample) and use .Navigate and other functions. How can I do this? (im using visual studio 6 c++)

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  • Is there a way to force JUnit to fail on ANY unchecked exception, even if swallowed

    - by Uri
    I am using JUnit to write some higher level tests for legacy code that does not have unit tests. Much of this code "swallows" a variety of unchecked exceptions like NullPointerExceptions (e.g., by just printing stack trace and returning null). Therefore the unit test can pass even through there is a cascade of disasters at various points in the lower level code. Is there any way to have a test fail on the first unchecked exception even if they are swallowed? The only alternative I can think of is to write a custom JUnit wrapper that redirects System.err and then analyzes the output for exceptions.

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  • Generate set/get methods for a c++ class

    - by Narek
    Is there any tool that generates set and get methods for a class. Just I create classes very frequently and would like to have a tool which for each class-member wil generate following functions: Member_Type getMemberName() const; void setMemberName(const Member_Type & val);

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  • Hibernate Initial SessionFactory creation failed

    - by user364746
    Hello.. I'm trying to use hibernate to fill my jsf selectonemenu in ApplicationBean (in Liferay). The problem is that I got Initial SessionFactory creation failed problem. Before putting my functions in the applicationbean I was setting them in sessionbean and I got no error. For now the full error Initial SessionFactory creation failed.java.lang.ClassCastException: org.hibernate.type.StringType cannot be cast to org.hibernate.type.VersionType Thanks

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  • *iPhone* Unable to symbolicate in Object Allocations instrument

    - by AkademiksQc
    Hi there, i run a C++ app from objective-c I can successfully symbolicate my function names using Shark profiler but not with the Object Allocations instrument.à In the detailed pane, i only see my C++ app name with the hexadecimal value for my C++ functions. I tried to do a "File/Re-Symbolicate Document", selecting my app folder containing both my app and my Dsym file but nothing change. Any clues? My config: xCode 3.2.2 iPhonoe SDK 3.2 Snowleopard (10.6.3) Thx.

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  • About curse of dimensionality

    - by Dan
    My question is about this topic I've been reading about a bit. Basically my understanding is that in higher dimensions all points end up being very close to each other. The doubt I have is whether this means that calculating distances the usual way (euclidean for instance) is valid or not. If it were still valid, this would mean that when comparing vectors in high dimensions, the two most similar wouldn't differ much from a third one even when this third one could be completely unrelated. Is this correct? Then in this case, how would you be able to tell whether you have a match or not?

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  • Where can I find documentation for Scala's delayed function calls?

    - by Geo
    I saw a delayed example in David Pollak's "Beginning Scala". I tried to adapt that, by trial and error. Here's what I have: def sayhello() = { println("hello") } def delaying(t: => Unit):Unit = { println("before call") t println("after call") } delaying(sayhello()) How would you delay a function/method that takes parameters? Why can't I use parantheses when I call t? Where can I find more documentation on delaying functions?

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  • Is there a concise way to map a string to an enum in Objective-C?

    - by zekel
    I have a string I want to parse and return an equivalent enum. I need to use the enum type elsewhere, and I think I like how I'm defining the class. The problem is that I don't know a good way to check the string against the enum values without being redundant about the order of the enums. typedef enum { ZZColorRed, ZZColorGreen, ZZColorBlue, } ZZColorType; - (ZZColorType)parseColor:(NSString *)inputString { // inputString will be @"red", @"green", or @"blue" (trust me) // how can I turn that into ZZColorRed, etc. without // redefining their order like this? NSArray *colors = [NSArray arrayWithObjects:@"red", @"green", @"blue", nil]; return [colors indexOfObject:inputString]; } In Python, I'd probably do something like the following, although to be honest I'm not in love with that either. ## maps url text -> constant string RED_CONSTANT = 1 BLUE_CONSTANT = 2 GREEN_CONSTANT = 3 TYPES = { 'red': RED_CONSTANT, 'green': GREEN_CONSTANT, 'blue': BLUE_CONSTANT, } def parseColor(inputString): return TYPES.get(inputString) ps. I know there are color constants in Cocoa, this is just an example.

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  • lua - how to call function from above it in code (prior to it being defined)?

    - by Greg
    what is the syntax (i.e. code example) in Lua so you can call a function prior to it being defined? i.e. how do you kind of create the function, but then add it's implementation further down in code. So roughly like this: define function name (doX) here somehow (i.e. subject of this question) call doX here (further down in the code) doX implemention here (i.e. all functions down at the bottom of the file)

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  • Read vs Find -- Cakephp Usage

    - by Michael
    Hi all, I was reading through a book on CakePhp Application structure, and came across both the read and find functions. I've always only used find -- when would a read be appropriate? Examples appreciated. Thanks!

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  • Production ready alternative to Microsoft Doloto (Javascript minifier/prefetcher)?

    - by usr
    As you surely know Microsoft Doloto is tool which profiles you javascript code as it actually runs on the page and splits it in to two files: one file will be statically included in the footer of the page which contains stubs for all functions and loads the actual implementations (in file 2) in the background (under the assumption that only very litte javascript is needed on page load so you can defer downloading the rest). I found Doloto not to be production ready, it meanwhile has been canceled afaik. Is there a working alternative?

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  • Python: Sorting array with custom pattern

    - by Binka
    In my little project here I have sorted a list in decending order, however, my goal is to sort it in this custom pattern. (largest - smallest - next largest - next smallest -)etc. In java I was able to do this like this... My goal is to do the same thing but in python, except backwards. Any ideas on how to convert that last for loop that does the wackysort into python and make it go backwards? public static void wackySort(int[] nums){ //first, this simply sorts the array by ascending order. int sign = 0; int temp = 0; int temp2 = 0; for (int i = 0; i < nums.length; i++){ for (int j = 0; j < nums.length -1; j++){ if (nums[j] > nums[j+1]){ temp = nums[j]; nums[j] = nums[j+1]; nums[j+1] = temp; } } } //prepare for new array to actually do the wacky sort. System.out.println(); int firstPointer = 0; int secondPointer = nums.length -1; int[] newarray = new int[nums.length]; int size = nums.length; //for loop that increments by two taking second slot replacing the last (n-1) term for (int i = 0; i < nums.length -1; i+=2){ newarray[i] = nums[firstPointer++]; newarray[i+1] = nums[secondPointer--]; } //storing those values back in the nums array for (int i = 0; i < nums.length; i++){ nums[i] = newarray[i]; } }

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  • Update 2 table values in one query in LINQ

    - by fireBand
    Hello, I have 2 tables Table1 with columns [BId,Name,Amount] Table2 with columns [CId,BId, ExpenseType,Expense]. BId Is the foreign key in Table2. The Amount field in Table1 is always higher than Expense in Table2. I need to update the values of Amount (increase or decrease) based on value of Expense and I want to do it in single query in LINQ. Eg If the Expense has to be updated with 200, I would decrease(negate) Amount value with 200. If Expense is reduce to 100 then the Amount is increased by a value of 100. Thanks in advance for any suggestions.

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