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  • Django - 2 fields unique together

    - by webvulture
    Suppose, I want to record say poll choices by users everyday. In this case, i have a table named vote which has columns poll , choice and user-id . So how can i out the constraint (maybe in the django models or wherever possible) that poll and user-id both should not be the same for any entry but like the same user can vote for various different polls once and obviously various users can vote for the same poll. I hope I am clear.

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  • Retrieving a unique result set with Core Data

    - by randombits
    I have a core data based app that manages a bunch of entities. I'm looking to be able to do the following. I have an entity "SomeEntity" with the attributes: name, type, rank, foo1, foo2. Now, SomeEntity has several rows if when we're speaking strictly in SQL terms. What I'm trying to accomplish is to retrieve only available types, even though each instance can have duplicate types. I also need them returned in order according to rank. So in SQL, what I'm looking for is the following: SELECT DISTINCT(type) ORDER BY rank ASC Here is the code I have so far that's breaking: NSError *error = NULL; NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; [fetchRequest setReturnsDistinctResults:YES]; [fetchRequest setPropertiesToFetch:[NSArray arrayWithObjects:@"type", @"rank", nil]]; NSEntityDescription *entity = [NSEntityDescription entityForName:@"SomeEntity" inManagedObjectContext:managedObjectContext]; [fetchRequest setEntity:entity]; // sort by rank NSSortDescriptor *rankDescriptor = [[NSSortDescriptor alloc] initWithKey:@"rank" ascending:YES]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:rankDescriptor,nil]; [fetchRequest setSortDescriptors:sortDescriptors]; [sortDescriptors release]; [rankDescriptor release]; NSArray *fetchResults = [managedObjectContext executeFetchRequest:fetchRequest error:&error]; [fetchRequest release]; return fetchResults; Right now that is crashing with the following: Invalid keypath section passed to setPropertiesToFetch:

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  • R- delete rows in multiple columns by unique number

    - by Vincent Moriarty
    Given data like this C1<-c(3,-999.000,4,4,5) C2<-c(3,7,3,4,5) C3<-c(5,4,3,6,-999.000) DF<-data.frame(ID=c("A","B","C","D","E"),C1=C1,C2=C2,C3=C3) How do I go about removing the -999.000 data in all of the columns I know this works per column DF2<-DF[!(DF$C1==-999.000 | DF$C2==-999.000 | DF$C3==-999.000),] But I'd like to avoid referencing each column. I am thinking there is an easy way to reference all of the columns in a particular data frame aka: DF3<-DF[!(DF[,]==-999.000),] or DF3<-DF[!(DF[,(2:4)]==-999.000),] but obviously these do not work And out of curiosity, bonus points if you can me why I need that last comma before the ending square bracket as in: ==-999.000),]

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  • Unique DVD info?

    - by acidzombie24
    I was wondering, is there some type of disc ID i can use to search in my database to see if that disc is has been scanned or not? All disc were created by me typically burnt on windows. -edit- I could compare write time and volume label to see if the disc has been scanned but i notice if i put in certain commercial disc that fields are blank or wrong causing many false positives (i once had the time set to the future, i dont know if people want to archive the contents of files on a commercial disc in my app).

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  • PHP While loop seperating unique categories from multiple 'Joined' tables

    - by Hob
    I'm pretty new to Joins so hope this all makes sense. I'm joining 4 tables and want to create a while loop that spits out results nested under different categories. My Tables categories id | category_name pages id | page_name | category *page_content* id | page_id | image_id images id | thumb_path My current SQL join <?php $all_photos = mysql_query(" SELECT * FROM categories JOIN pages ON pages.category = categories.id JOIN image_pages ON image_pages.page_id = pages.id JOIN images ON images.id = image_pages.image_id ");?> The result I want from a while loop I would like to get something like this.... Category 1 page 1 Image 1, image 2, image 3 page 2 Image 2, image 4 Category 2 page 3 image 1 page 4 image 1, image 2, image 3 I hope that makes sense. Each image can fall under multiple pages and each page can fall under multiple categories. at the moment I have 2 solutions, one which lists each category several times according to the the amount of pages inside them: eg. category 1, page 1, image 1 - category 1, page 1, image 2 etc One that uses a while loop inside another while loop inside another while loop, resulting in 3 sql queries. <?php while($all_page = mysql_fetch_array($all_pages)) { ?> <p><?=$all_page['page_name']?></p> <?php $all_images = mysql_query("SELECT * FROM images JOIN image_pages ON image_pages.page_id = " . $all_page['id'] . " AND image_pages.image_id = images.id"); ?> <div class="admin-images-block clearfix"> <?php while($all_image = mysql_fetch_array($all_images)) { ?> <img src="<?=$all_image['thumb_path']?>" alt="<?=$all_image['title']?>"/> <?php } ?> </div> <?php } } ?

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  • Regex to validate for Unique Well Identifier in rails

    - by Jasper502
    I am a regex newbie and can't seem to figure this one out. Here is a link to the required string formats: http://earth.gov.bc.ca/royp-bin/phcgi.exe?PH_QKC=DOCUWI&PH_APP=RMSprodApp&PH_HTML=DOCUWI.htm For example: 100041506421W500 = 1+0+{01-16}+{01-36}+{001-129}+{01-36}+W+{1-6}+0+{0-9} I tried this: ^10[0|2-9]{1}0*([1-9]|1[0-6])0*([1-9]|[12][0-9]|3[0-6])0*([1-9][0-9]|1[0-2][0-9])0*([1-9]|[12][0-9]|3[0-6])W[1-6]0[0-9]$ In a regex validator and it sort of works except that 1041506421W500 and 10000000041506421W500 validates. The entire string can only be 16 characters long. I am pretty sure I am missing something obvious here regarding the leading zeros. Tried the NTS format and running into the same sort of problems.

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  • Core data fetch only returns unique managed objects

    - by JK
    I execute a core data fetch which specifies a predicate as follows: NSPredicate *predicate = [NSPredicate predicateWithFormat:@"identifier IN %@", favoritesIDs]; When there are duplicate items in the favoriteIDs array, the fetch request only returns 1 managed object. How can I ensure that more than one instance is fetched? Thank you.

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  • LINQ, creating unique collection of a collection

    - by Wish
    I have class Vertex and a class Edge (Edge holds 2 properties - Vertex Source and Vertex Target); Edges and Vertexes are collected into lists Some example: A-->B // edge from vertex A to B B-->C // edge from vertex B to C C-->A // edge from vertex C to A A-->C // edge from vertex A to C -- this is two way edge So I would like to make IDictionary<Edge, bool> which would hold edges (A--B and B--A would be like 1), and bool - if it is two way or no. I need it because when I draw them now, it draws 2 arrows under one another. I would better make 1 arrow. So I'm pretty stuck right here... May anybody help me a bit ?

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  • Prolog: find all numbers of unique digits that can be formed from a list of digits

    - by animo
    The best thing I could come up with so far is this function: numberFromList([X], X) :- digit(X), !. numberFromList(List, N) :- member(X, List), delete(List, X, LX), numberFromList(LX, NX), N is NX * 10 + X. where digit/1 is a function verifying if an atom is a decimal digit. The numberFromList(List, N) finds all the numbers that can be formed with all digits from List. E.g. [2, 3] -> 23, 32. but I want to get this result: [2, 3] -> 2, 3, 23, 32 I spent a lot of hours thinking about this and I suspect you might use something like append(L, _, List) at some point to get lists of lesser length. I would appreciate any contribution.

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  • Providing unique layout for specific resolution in Android 2.3.3

    - by user1384991
    I need to use specific xml-layouts based on screen resolution, not size. So, the first design is used for resolution <= 480x800, and the second - for resolution = 480x800. How is it done ? update. Possible solution: Display display = ((WindowManager) getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay(); final int height = display.getHeight(); final int width = display.getWidth();

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  • unique selling points: php, flash, rails

    - by pwebdev
    on reflecting how to talk with prospect customers on technologies for web applications, what are important requirements for chosing a specific technology? I am biased towards ruby on rails, but the code base and community of PHP is larger, while the user experience of flash sites is often an advantage to the segment of higher paying customers. how would you argue for or against the usage of a technology in general? for ruby on rails in particular?

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  • SQL - get latest records from table where field is unique

    - by 89stevenharris
    I have a table of data as follows id status conversation_id message_id date_created 1 1 1 72 2012-01-01 00:00:00 2 2 1 87 2012-03-03 00:00:00 3 2 2 95 2012-05-05 00:00:00 I want to get all the rows from the table in date_created DESC order, but only one row per conversation_id. So in the case of the example data above, I would want to get the rows with id 2 and 3. Any advice is much appreciated.

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  • How to get unique value in jquery?

    - by jquerier
    I am learning jquery. I have following chunk of code in a html file: <table width="100%"> <tr> <td align='center'> <div> <a id='get_this' href='#'> <input type='hidden' id='id' value='1'><img src='images/1.gif'></a> </div> </td> <td align='center'> <div> <a id='get_this' href='#'> <input type='hidden' id='id' value='2'><img src='images/2.gif'></a> </div> </td> <td align='center'> <div> <a id='get_this' href='#'> <input type='hidden' id='id' value='3'><img src='images/3.gif'></a> </div> </td> </tr> What I want to do is, when I click any of the image, I can get the value, so that I can display the information. For example, I click the id=1, then I will display information on id1 in somewhere else. I tried this: $("a#get_this").click(function(){ var id = $('input[type=hidden]#id').val(); window.alert("You have chosen the id: " + id); }); It always return id: 1 to me.

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  • ZendFramework Headscript Helper - Make scripts unique

    - by tokam
    How can I ensure that the headScript and headStyle helper include css files only once when added? The reason I am asking is that I would like to display some contents in a lightbox and all Flashmassages.E.g. notifications like profile successfully edited. To display flashmessages in the lightbox i would like to check at the top of my layout script if they are set, in case they are i would like to attach the required javascript library using the headScript helper. The problem is that I have no control about the scripts which were already added at this point. Maybe at a page where the library is needed for an other use case, it has already been added with addScript. How can I ensure all scripts are added only once to my helper? I already checked that these helpers extend Zend_View_Helper_Placeholder_Container_Standalone which uses an ArrayObject internally to hold the data and provides getters & setter to the array object. Maybe a solution here would be to check each time when adding a script file if it already exists using the ArrayObject?

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  • Select only the first rows for each unique value of a column in R

    - by dmvianna
    From a dataframe like this test <- data.frame('id'= rep(1:5,2), 'string'= LETTERS[1:10]) test <- test[order(test$id), ] rownames(test) <- 1:10 > test id string 1 1 A 2 1 F 3 2 B 4 2 G 5 3 C 6 3 H 7 4 D 8 4 I 9 5 E 10 5 J I want to create a new one with the first appearance of each id / string pair. If sqldf accepted R code within it, the query could look like this: res <- sqldf("select id, min(rownames(test)), string from test group by id, string") > res id string 1 1 A 3 2 B 5 3 C 7 4 D 9 5 E Is there a solution short of creating a new column like test$row <- rownames(test) and running the same sqldf query with min(row)?

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  • How to create unique user key

    - by Grayson Mitchell
    Scenario: I have a fairly generic table (Data), that has an identity column. The data in this table is grouped (lets say by city). The users need an identifier in order for printing on paper forms, etc. The users can only access their cites data, so if they use the identity column for this purpose they will see odd numbers (e.g. a 'New York' user might see 1,37,2028... as the listed keys. Idealy they would see 1,2,3... (or something similar) The problem of course is concurrency, this being a web application you can't just have something like: UserId = Select Count(*)+1 from Data Where City='New York' Has anyone come up with any cunning ways around this problem?

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  • How to use Groovy Set for unique elements?

    - by Guy
    As simple as this must be I still can't understand where am I wrong: class A { boolean equals(o) { true } } def s = [new A(), new A()] as Set assert s.size() == 1 // Assertion failed: actually gives 2 Which method should I override in order to get uniqueness?

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  • Remove a single non-unique value from a sequence in F#

    - by mavnn
    I have a sequence of integers representing dice in F#. In the game in question, the player has a pool of dice and can choose to play one (governed by certain rules) and keep the rest. If, for example, a player rolls a 6, 6 and a 4 and decides to play one the sixes, is there a simple way to return a sequence with only one 6 removed? Seq.filter (fun x -> x != 6) dice removes all of the sixes, not just one.

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  • Selecting unique elements using XSLT.

    - by AJ
    I have the following XML: <option> <title>ABC</title> <desc>123</desc> </option> <option> <title>ABC</title> <desc>12345</desc> </option> <option> <title>ABC</title> <desc>123</desc> </option> <option> <title>EFG</title> <desc>123</desc> </option> <option> <title>EFG</title> <desc>456</desc> </option> Using XSLT, I want to transform it into: <choice> <title>ABC</title> <desc>123</desc> <desc>12345</desc> </choice> <choice> <title>EFG</title> <desc>123</desc> <desc>456</desc> </choice>

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  • mysql query to get unique value from one column

    - by vesselyp
    i have a table named locations of which i want to select and get values in such a way that it should select only distinct values from a column but select all other values . table name: locations column names 1: country values : America, India, India, India column names 2: state/Province : Newyork, Punjab, Karnataka, kerala when i select i should get India only once and all the three states listed under India . is ther any way..??? sombody please help

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  • Print unique ascii characters in eclipse console

    - by Shaded
    Hey guys, Kind of a strange question but... here it goes. Recently my application threw an IOException that the text only had a clubs symbol in it (like the suit in cards) I know this is probably because there was a number in there that was cast to a char and printed to the screen, and I've found where that might have happened. The only problem is, I can't recreate it in eclipse because the eclipse console doesn't want to print those characters for me. All I get are boxes. I figure this is an encoding issue or something but I need eclipse to print out those characters just like the windows console would. Is there a setting I can change to do this?

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  • Create unique links for indvidual elements of a PHP generated table

    - by typoknig
    I have a table generated from some PHP code that lists a SMALL amount of important information for employees. I want to make it so each row, or at least one element in each row can be clicked on so the user will be redirected to ALL of the information (pulled from MySQL database) related to the employee who was clicked on. I am not sure how would be the best way to go about this, but I am open to suggestions. I would like to stick to PHP and/or JavaScript. Below is the code for my table: <table> <tr> <td id="content_heading" width="25px">ID</td> <td id="content_heading" width="150px">Last Name</td> <td id="content_heading" width="150px">First Name</td> <td id="content_heading" width="75px">SSN</td> </tr> <?php $user = 'user'; $pass = 'pass'; $server = 'localhost'; $link = mysql_connect($server, $user, $pass); if (!$link){ die('Could not connect to database!' . mysql_error()); } mysql_select_db('mydb', $link); $query = "SELECT * FROM employees"; $result = mysql_query($query); mysql_close($link); $num = mysql_num_rows($result); for ($i = 0; $i < $num; $i++){ $row = mysql_fetch_array($result); $class = (($i % 2) == 0) ? "table_odd_row" : "table_even_row"; echo "<tr class=".$class.">"; echo "<td>".$row[id]."</td>"; echo "<td>".$row[l_name]."</td>"; echo "<td>".$row[f_name]."</td>"; echo "<td>".$row[ssn]."</td>"; echo "</tr>"; } ?> </table>

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