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  • Validationattribute only when value is changed?

    - by boris callens
    I want to write a custom ValidationAttribute that checks if the given value is unique or not. The problem is that in the edit screen, it is not guaranteed that the user actually changed the value, resulting in a false error. Is there a way to check in my attribute whether the value actually changed? Or can I trigger the attribute only when the value has changed? I'm getting the feeling this requirement maybe just doesn't belong in an attribute?

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  • Can you make an incrementing compiler constant?

    - by Keith Nicholas
    While sounding nonsensical..... I want a Contant where every time you use it it will increment by 1 int x; int y; x = INCREMENTING_CONSTNAT; y = INCREMENTING_CONSTNAT; where x == 1; and y == 2 Note I don't want y = INCREMENTING_CONSTNAT+1 type solutions. Basically I want to use it as a compile time unique ID ( generally it wouldn't be used in code like the example but inside another macro)

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  • Image upload storage strategies

    - by MatW
    When a user uploads an image to my site, the image goes through this process; user uploads pic store pic metadata in db, giving the image a unique id async image processing (thumbnail creation, cropping, etc) all images are stored in the same uploads folder So far the site is pretty small, and there are only ~200,000 images in the uploads directory. I realise I'm nowhere near the physical limit of files within a directory, but this approach clearly won't scale, so I was wondering if anyone had any advice on upload / storage strategies for handling large volumes of image uploads.

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  • True or False: Good design calls for every table to have a primary key, if nothing else, a running i

    - by Velika
    Consider a grocery store scenario (I'm making this up) where you have FACT records that represent a sale transaction, where the columns of the Fact table include SaleItemFact Table ------------------ CustomerID ProductID Price DistributorID DateOfSale Etc Etc Etc Even if there are duplicates in the table when you consider ALL the keys, I would contend that a surrogate running numeric key (i.e. identity column) should be made up, e.g., TransactionNumber of type Integer. I can see someone arguing that a Fact table might not have a unique key (though I'd invent one and waste the 4 bytes, but how about a dimension table?

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  • Send activation email to user

    - by Martin
    How would I do to check if a email actially exists? Cant understand how sites do to send mails with a unique link that the users clicks to validate that he is the owner of email =/ Make a 2 new columns called activationkey and activated and store some random string, send an email with the activationkey, and update the users activated =1 that match that activation link register.php?a=activate&key=9cdfb439c7876e703e307864c9167a15 Any better ideas?

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  • What's the best way to use NHibernate for objects without ID?

    - by Khash
    I have some classes in my app that don't require an ID to be persisted. These could be things like user logs or audit records. I can add an arbitaty id to them but I would like to avoid that as they don't mean anything. The retrieval of these objects is always on another key (like UserId) which is not unique to the record.

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  • SQL - First row inserted every day for the past X days

    - by okie.floyd
    A tough SQL question (I'm using postgres by the way). I need the first row inserted every day for the past X days. one of my columns is a timestamp, which i hold the time inserted, and another column is the row id. If it's not possible to get the first row inserted every day, i at least need a unique one; a single row for every day for the past x days. Any suggestions? Thanks okie

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  • Java portal architectural considerations

    - by Woot4Moo
    Currently there exists a need to create an application that will serve 5 different customers each requiring their own specific URL and content repository. My question is when designing this application what should my considerations be for protecting the content of the individual customers while meeting the requirements of the unique URL. The system will be sitting on Windows with a postgres database and java as the implementation language.

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  • Circular database relationships. Good, Bad, Exceptions?

    - by jim
    I have been putting off developing this part of my app for sometime purely because I want to do this in a circular way but get the feeling its a bad idea from what I remember my lecturers telling me back in school. I have a design for an order system, ignoring the everything that doesn't pertain to this example I'm left with: CreditCard Customer Order I want it so that, Customers can have credit cards (0-n) Customers have orders (1-n) Orders have one customer(1-1) Orders have one credit card(1-1) Credit cards can have one customer(1-1) (unique ids so we can ignore uniqueness of cc number, husband/wife may share cc instances ect) Basically the last part is where the issue shows up, sometimes credit cards are declined and they wish to use a different one, this needs to update which their 'current' card is but this can only change the current card used for that order, not the other orders the customer may have on disk. Effectively this creates a circular design between the three tables. Possible solutions: Either Create the circular design, give references: cc ref to order, customer ref to cc customer ref to order or customer ref to cc customer ref to order create new table that references all three table ids and put unique on the order so that only one cc may be current to that order at any time Essentially both model the same design but translate differently, I am liking the latter option best at this point in time because it seems less circular and more central. (If that even makes sense) My questions are, What if any are the pros and cons of each? What is the pitfalls of circular relationships/dependancies? Is this a valid exception to the rule? Is there any reason I should pick the former over the latter? Thanks and let me know if there is anything you need clarified/explained. --Update/Edit-- I have noticed an error in the requirements I stated. Basically dropped the ball when trying to simplify things for SO. There is another table there for Payments which adds another layer. The catch, Orders can have multiple payments, with the possibility of using different credit cards. (if you really want to know even other forms of payment). Stating this here because I think the underlying issue is still the same and this only really adds another layer of complexity.

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  • Need help with copy constructor for very basic implementation of singly linked lists

    - by Jesus
    Last week, we created a program that manages sets of strings, using classes and vectors. I was able to complete this 100%. This week, we have to replace the vector we used to store strings in our class with simple singly linked lists. The function basically allows users to declare sets of strings that are empty, and sets with only one element. In the main file, there is a vector whose elements are a struct that contain setName and strSet (class). HERE IS MY PROBLEM: It deals with the copy constructor of the class. When I remove/comment out the copy constructor, I can declare as many empty or single sets as I want, and output their values without a problem. But I know I will obviously need the copy constructor for when I implement the rest of the program. When I leave the copy constructor in, I can declare one set, either single or empty, and output its value. But if I declare a 2nd set, and i try to output either of the first two sets, i get a Segmentation Fault. Moreover, if i try to declare more then 2 sets, I get a Segmentation Fault. Any help would be appreciated!! Here is my code for a very basic implementation of everything: Here is the setcalc.cpp: (main file) #include <iostream> #include <cctype> #include <cstring> #include <string> #include "help.h" #include "strset2.h" using namespace std; // Declares of structure to hold all the sets defined struct setsOfStr { string nameOfSet; strSet stringSet; }; // Checks if the set name inputted is unique bool isSetNameUnique( vector<setsOfStr> strSetArr, string setName) { for(unsigned int i = 0; i < strSetArr.size(); i++) { if( strSetArr[i].nameOfSet == setName ) { return false; } } return true; } int main(int argc, char *argv[]) { char commandChoice; // Declares a vector with our declared structure as the type vector<setsOfStr> strSetVec; string setName; string singleEle; // Sets a loop that will constantly ask for a command until 'q' is typed while (1) { // declaring a set to be empty if(commandChoice == 'd') { cin >> setName; // Check that the set name inputted is unique if (isSetNameUnique(strSetVec, setName) == true) { strSet emptyStrSet; setsOfStr set1; set1.nameOfSet = setName; set1.stringSet = emptyStrSet; strSetVec.push_back(set1); } else { cerr << "ERROR: Re-declaration of set '" << setName << "'\n"; } } // declaring a set to be a singleton else if(commandChoice == 's') { cin >> setName; cin >> singleEle; // Check that the set name inputted is unique if (isSetNameUnique(strSetVec, setName) == true) { strSet singleStrSet(singleEle); setsOfStr set2; set2.nameOfSet = setName; set2.stringSet = singleStrSet; strSetVec.push_back(set2); } else { cerr << "ERROR: Re-declaration of set '" << setName << "'\n"; } } // using the output function else if(commandChoice == 'o') { cin >> setName; if(isSetNameUnique(strSetVec, setName) == false) { // loop through until the set name is matched and call output on its strSet for(unsigned int k = 0; k < strSetVec.size(); k++) { if( strSetVec[k].nameOfSet == setName ) { (strSetVec[k].stringSet).output(); } } } else { cerr << "ERROR: No such set '" << setName << "'\n"; } } // quitting else if(commandChoice == 'q') { break; } else { cerr << "ERROR: Ignoring bad command: '" << commandChoice << "'\n"; } } return 0; } Here is the strSet2.h: #ifndef _STRSET_ #define _STRSET_ #include <iostream> #include <vector> #include <string> struct node { std::string s1; node * next; }; class strSet { private: node * first; public: strSet (); // Create empty set strSet (std::string s); // Create singleton set strSet (const strSet &copy); // Copy constructor // will implement destructor later void output() const; strSet& operator = (const strSet& rtSide); // Assignment }; // End of strSet class #endif // _STRSET_ And here is the strSet2.cpp (implementation of class) #include <iostream> #include <vector> #include <string> #include "strset2.h" using namespace std; strSet::strSet() { first = NULL; } strSet::strSet(string s) { node *temp; temp = new node; temp->s1 = s; temp->next = NULL; first = temp; } strSet::strSet(const strSet& copy) { cout << "copy-cst\n"; node *n = copy.first; node *prev = NULL; while (n) { node *newNode = new node; newNode->s1 = n->s1; newNode->next = NULL; if (prev) { prev->next = newNode; } else { first = newNode; } prev = newNode; n = n->next; } } void strSet::output() const { if(first == NULL) { cout << "Empty set\n"; } else { node *temp; temp = first; while(1) { cout << temp->s1 << endl; if(temp->next == NULL) break; temp = temp->next; } } } strSet& strSet::operator = (const strSet& rtSide) { first = rtSide.first; return *this; }

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  • Hibernate naturalID

    - by DD
    Hibernate doesnt seem to generate a notnull constraint on a field I marked as naturalID. Is this normal? @MappedSuperclass public class AbstractDomainObject extends PersistentObject { @NaturalId private String code; DB Schema: CONSTRAINT SYS_CT_47 UNIQUE(CODE) There is no not null constraint here.

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  • General workflow to allow multiple OpenIDs to be associated with one app account

    - by BobTodd
    I have a (typical?) scenario: that my app's users can use multiple openids mapped to one app account (like stackoverflow). For me the unique thing on the account is the email address, so this binds openids to the profile. Question is, how to allow a user to start using a second openid once one is setup. I am asking as I have read that it is a security hole to allow automatic account openid syncing simply based on the provider-supplied email address as someone could easily spoof someone's email address to create a spoof openid and falsely access the account (how I am not sure) - although this seems to be exactly how stack operates. See options a. and b. below. Problem for me with a. is what happens if the original openid no longer works for whatever reason - how would you set-up a new openid? Would b. be more acceptable if we used email verification? Does anyone have an article detailing a "standard" way (set of user stories) for this - it seems to be an increasingly popular way to authenticate. I have tried to detail this in a rough decision tree... 1. My Site > authentication landing page - user chooses an openid (facebook, google, myopenid etc), redirection > 2. Provider site returns with token (includes user registering a new openid, logging in or is already logged in to Provider site) 3. My Site > use token id to lookup user 3.1 Profile exists? Yes > authenticate. ends. No > 3.1.1 was email address supplied by provider? Yes > lookup user by email address 3.1.1.1 Profile exists? Yes > a. error message - please login with existing openid and associate this openid (from special page) Yes > b. or associate this openid with existing profile automatically. authenticate. ends. No > Register profile. With registration email address follow 3.1.1, except this time where email is unique, we will associate openid. ends

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  • C - How to implement Set data structure?

    - by psihodelia
    Is there any tricky way to implement a set data structure (a collection of unique values) in C? All elements in a set will be of the same type and there is a huge RAM memory. As I know, for integers it can be done really fast'N'easy using value-indexed arrays. But I'd like to have a very general Set data type. And it would be nice if a set could include itself.

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  • How to get last full MS SQL Server error message?

    - by JohnM2
    I am aware of: SELECT @@ERROR but it will give me only an ERROR CODE (a number) and I need a full text message like: Cannot insert duplicate key row in object 'dbo.TABLE_NAME' with unique index 'IX_ID_unique'. The statement has been terminated. How can I do that in MS Sql Server 2005 ?

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  • How does the Ableton warp algorithm work exactly?

    - by pepperdreamteam
    I'm looking for any documentation or definitive information on Ableton's warp feature. I understand that it has something to do with finding transients, aligning them with an even rhythm and shifting audio samples accordingly. I'm hoping to find ways to approximate warping with more basic audio editing tools. I understand that this is ableton's unique device, really any information about how it works would be helpful. So...does anyone have any 411?

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  • codeIgniter: pass parameter to a select query from previous query

    - by krike
    I'm creating a little management tool for the browser game travian. So I select all the villages from the database and I want to display some content that's unique to each of the villages. But in order to query for those unique details I need to pass the id of the village. How should I do this? this is my code (controller): function members_area() { global $site_title; $this->load->model('membership_model'); if($this->membership_model->get_villages()) { $data['rows'] = $this->membership_model->get_villages(); $id = 1;//this should be dynamic, but how? if($this->membership_model->get_tasks($id)): $data['tasks'] = $this->membership_model->get_tasks($id); endif; } $data['title'] = $site_title." | Your account"; $data['main_content'] = 'account'; $this->load->view('template', $data); } and this is the 2 functions I'm using in the model: function get_villages() { $q = $this->db->get('villages'); if($q->num_rows() > 0) { foreach ($q->result() as $row) { $data[] = $row; } return $data; } } function get_tasks($id) { $this->db->select('name'); $this->db->from('tasks'); $this->db->where('villageid', $id); $q = $this->db->get(); if($q->num_rows() > 0) { foreach ($q->result() as $task) { $data[] = $task; } return $data; } } and of course the view: <?php foreach($rows as $r) : ?> <div class="village"> <h3><?php echo $r->name; ?></h3> <ul> <?php foreach($tasks as $task): ?> <li><?php echo $task->name; ?></li> <?php endforeach; ?> </ul> <?php echo anchor('site/add_village/'.$r->id.'', '+ add new task'); ?> </div> <?php endforeach; ?> ps: please do not remove the comment in the first block of code!

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  • advance/basic and smartphone views in Rails

    - by aleds
    In a new Rail app I have to consider 2 differents user's type: basic and Advanced and I have to create smartphone views( unique view for both user's type). Then I have 3 view/layout: - web advance - web basic - smartphone I already have the adv/basic flag for the user, and I followed the RBates tutorial http://asciicasts.com/episodes/199-mobile-devices. What is the best way to manage the 3 views/layout ?

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  • Is using joins in select clause slow in Oracle?

    - by gniquil
    I would like to write a query like the following select username, (select state from addresses where addresses.username = users.username) email from users This works in Oracle (assuming the result from the inner query is unique). However, is there a performance penalty associated with this style of writing query?

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  • Table for each region in MySQL

    - by King Wu
    There are four regions with more than one million records total. Should I create a table with a region column or a table for each region and combine them to get the top ranks? If I combine all four regions, none of my columns will be unique so I will need to also add an id column for my primary key. Otherwise, name, accountId & characterId would be candidate keys or should I just add an id column anyways. Table: ---------------------------------------------------------------- | name | accountId | iconId | level | characterId | updateDate | ----------------------------------------------------------------

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  • Sorting string column containing numbers in SQL?

    - by Ish
    Dear Folks, I am trying to sort string column (containing numbers). // SELECT `name` FROM `mytable` ORDER BY `name` ASC +----------+ +-- name --+ +----------+ +-- a 1 ---+ +-- a 12 --+ +-- a 2 ---+ +-- a 3 ---+ You see natural sorting algorithm of Mysql is placing a 12 after a 1 (which is ok for most apps), But I have unique needs, so I want result should be sorted like this. +----------+ +-- name --+ +----------+ +-- a 1 ---+ +-- a 2 ---+ +-- a 3 ---+ +-- a 12 --+ Is it possible with just SQL, or I have to manipulate result-set at application level? Thanks for reading...

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