Search Results

Search found 22078 results on 884 pages for 'composite primary key'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 98/884 | < Previous Page | 94 95 96 97 98 99 100 101 102 103 104 105  | Next Page >

  • get foreign key objects in a single query - Django

    - by John
    Hi I have 2 models in my django code: class ModelA(models.Model): name = models.CharField(max_length=255) description = models.CharField(max_length=255) created_by = models.ForeignKey(User) class ModelB(models.Model): category = models.CharField(max_length=255) modela_link = models.ForeignKey(ModelA, 'modelb_link') functions = models.CharField(max_length=255) created_by = models.ForeignKey(User) Say ModelA has 100 records, all of which may or may not have links to ModelB Now say I want to get a list of every ModelA record along with the data from ModelB I would do: list_a = ModelA.objects.all() Then to get the data for ModelB I would have to do for i in list_a: i.additional_data = i.modelb_link.all() However this runs a query on every instance of i. Thus making 101 queries to run. Is there any way of running this all in just 1 query. Or at least less than the 101 queries. I've tried putting in ModelA.objects.select_related().all() but this didn't seem to have any effect. Thanks

    Read the article

  • Why the generated key size is not constant?

    - by Tom Brito
    The following code prints randomly 634, 635, 636, each time I run it. Why its not constant? public static void main(String[] args) throws Exception { KeyPairGenerator keyPairGen = KeyPairGenerator.getInstance("RSA", "BC"); keyPairGen.initialize(1024); RsaKeyPair keyPair = new RsaKeyPair(keyPairGen.generateKeyPair()); System.out.println(keyPair.getPrivate().getEncoded().length); }

    Read the article

  • Elegant way to aggregate multi-dimensional array by index key

    - by Stephen J. Fuhry
    How can I recursively find the total value of all children of an array that looks something like this? [0] => Array ( [value] => ? // 8590.25 + 200.5 + 22.4 [children] => Array ( [0] => Array ( [value] => ? // 8590.25 + 200.5 [children] => Array ( [0] => Array ( [value] => 8590.25 // leaf node ) [1] => Array ( [value] => 200.05 // leaf node ) ) ) [1] => Array ( [value] => 22.4 // leaf node ) ) )

    Read the article

  • Elegant way to distinct Path or Entry key

    - by sum1stolemyname
    I have an application loading CAD data (Custom format), either from the local filesystem specifing an absolute path to a drawing or from a database. Database access is realized through a library function taking the drawings identifier as a parameter. the identifiers have a format like ABC 01234T56-T, while my paths a typical windows Paths (eg x:\Data\cadfiles\cadfile001.bin). I would like to write a wrapper function Taking a String as an argument which can be either a path or an identifier which calls the appropriate functions to load my data. Like this: Function CadLoader(nameOrPath : String):TCadData; My Question: How can I elegantly decide wether my string is an idnetifier or a Path to a file? Use A regexp? Or just search for '\' and ':', which are not appearing in the Identifiers?

    Read the article

  • javascript : key validation

    - by Geetha
    hi all, im using javascript to validate keys in textbox. it is not working :( function numeric(e) { return ((e.keyCode == 8) || (e.keyCode == 9) || (e.keyCode > 47 && e.keyCode < 58) || (e.keyCode > 36 && e.keyCode < 41) || (e.keyCode == 46) || (e.keyCode > 95 && e.keyCode < 106) || e.keyCode == 190 || e.keyCode == 110); } help me...

    Read the article

  • Elegant way to aggregate multi-demensional array by index key

    - by Stephen J. Fuhry
    How can I recursively find the total value of all children of an array that looks something like this? [0] => Array ( [value] => ? // 8590.25 + 200.5 + 22.4 [children] => Array ( [0] => Array ( [value] => ? // 8590.25 + 200.5 [children] => Array ( [0] => Array ( [value] => 8590.25 // leaf node ) [1] => Array ( [value] => 200.05 // leaf node ) ) ) [1] => Array ( [value] => 22.4 // leaf node ) ) )

    Read the article

  • How to retrieve key and value from JSON object

    - by I Like PHP
    I have a JSON object in this format: { "supplier": { "mov_10": "love actually", "mov_1": "fare" }, "quantity": 20, "success": true, "length":2 } Now I want to create a select box below using the supplier object (using both the keys and values), like this: <select id="selectme"> <option id="mov_10">love actually</option> <option id="mov_1">fare</option> </select> So how do I create it? I just want to know how to reach mov_10 and mov_1 in the object. Sorry for my bad English, but please help me. Thanks.

    Read the article

  • Key Events in TabActivities?

    - by stormin986
    I have a TabActivity and want to catch and handle presses of HOME and BACK. Where do I need to catch these events? In my subclass of TabActivity I implement the following: @Override public boolean onKeyDown(int keyCode, KeyEvent event) { switch (keyCode) { // Code handling } return super.onKeyDown(keyCode, event); } Didn't work. So I placed a breakpoint on the switch statement line. But this function never gets called, whether I press volume up/down, menu, home, or back. Where do I need to catch these KeyEvents?

    Read the article

  • How to disable listbox auto select item when pressing key

    - by tomfox66
    I have a listbox where I want to copy and paste items within that listbox. Copy and paste works fine but everytime I press "Crtl + C" the item starting with the letter C is automatically selected. Can this automatic selection be disabled or am I missing something here Here is the copy and paste method I implemented: private void listBox_Script_KeyDown(object sender, KeyEventArgs e) { if (e.Control == true && e.KeyCode == Keys.C) { int test = listBox_Script.SelectedIndex; Clipboard.SetDataObject(listBox_Script.Items[listBox_Script.SelectedIndex], true); return; } if (e.Control == true && e.KeyCode == Keys.V) { if (Clipboard.GetDataObject().GetDataPresent(DataFormats.Text)) { listBox_Script.Items.Insert(listBox_Script.SelectedIndex + 1, Clipboard.GetDataObject().GetData(DataFormats.Text).ToString()); return; } }

    Read the article

  • Next Identity Key LINQ + SQL Server

    - by user569347
    To represent our course tree structure in our Linq Dataclasses we have 2 columns that could potentially be the same as the PK. My problem is that if I want to Insert a new record and populate 2 other columns with the PK that was generated there is no way I can get the next identity and stop conflict with other administrators who might be doing the same insert at the same time. Case: A Leaf node has right_id and left_id = itself (prereq_id) **dbo.pre_req:** prereq_id left_id right_id op_id course_id is_head is_coreq is_enforced parent_course_id and I basically want to do this: pre_req rec = new pre_req { left_id = prereq_id, right_id = prereq_id, op_id = 3, course_id = query.course_id, is_head = true, is_coreq = false, parent_course_id = curCourse.course_id }; db.courses.InsertOnSubmit(rec); try { db.SubmitChanges(); } Any way to solve my dilemma? Thanks!

    Read the article

  • Hibernate subclass with foreign key relationships

    - by shikarishambu
    I need some help defining the following object hierarchy/ database relationship in Hibernate From the object sense – Agent is inherited from Person and Agency is inherited from Organization. they are inherited from Party which can have multiple Addresses associated with it The database consists of Agent - ID - Name -PartyID (references Party.ID) Agency -ID -Name -PartyID (references Party.ID) Address -AddrID -PartyID (references Party.ID) -Street Party. -PartyID

    Read the article

  • Foreign Key Relationships

    - by Yehonathan Quartey
    I have two models class Subject(models.Model): name = models.CharField(max_length=100,choices=COURSE_CHOICES) created = models.DateTimeField('created', auto_now_add=True) modified = models.DateTimeField('modified', auto_now=True) syllabus = models.FileField(upload_to='syllabus') def __unicode__(self): return self.name and class Pastquestion(models.Model): subject=models.ForeignKey(Subject) year =models.PositiveIntegerField() questions = models.FileField(upload_to='pastquestions') def __unicode__(self): return str(self.year) Each Subject can have one or more past questions but a past question can have only one subject. I want to get a subject, and get its related past questions of a particular year. I was thinking of fetching a subject and getting its related past question. Currently am implementing my code such that I rather get the past question whose subject and year correspond to any specified subject like this_subject=Subject.objects.get(name=the_subject) thepastQ=Pastquestion.objects.get(year=2000,subject=this_subject) I was thinking there is a better way to do this. Or is this already a better way? Please Do tell ?

    Read the article

  • php values of one array to key of another array

    - by mark
    I have 2 arrays $arr1 = Array ( [0] => 12 [1] => 4 [2] => 8 [3] => xx [4] => 1 [5] => 1year [6] => 7 ) $arr2 = Array ( [0] => 1 [1] => 2 [2] => 3 [3] => 4 [4] => 5 [5] => 6 [6] => 7 ) I want to create a new array with the values of a2 as keys in $arr1. My resultant array should be like this $arr3 = Array ( [1] => 12 [2] => 4 [3] => 8 [4] => xx [5] => 1 [6] => 1year [7] => 7 )

    Read the article

  • Selecting dictionary items by key efficiently in Python

    - by user248237
    suppose I have a dictionary whose keys are strings. How can I efficiently make a new dictionary from that which contains only the keys present in some list? for example: # a dictionary mapping strings to stuff mydict = {'quux': ..., 'bar': ..., 'foo': ...} # list of keys to be selected from mydict keys_to_select = ['foo', 'bar', ...] The way I came up with is: filtered_mydict = [mydict[k] for k in mydict.keys() \ if k in keys_to_select] but I think this is highly inefficient because: (1) it requires enumerating the keys with keys(), (2) it requires looking up k in keys_to_select each time. at least one of these can be avoided, I would think. any ideas? I can use scipy/numpy too if needed.

    Read the article

  • Class templating std::set key types

    - by TomFLuff
    I have a class to evaluate set algebra but wish to template it. At the minute it looks a bit like this set.h: template<typename T> class SetEvaluation { public: SetEvaluation<T>(); std::set<T> evaluate(std::string in_expression); } set.cpp template<typename T> std::set<T> SetEvaluation<T>::evaluate(std::string expression) { std::set<T> result; etc etc... } But i'm getting undefined reference errors when compiling. Is it possible to declare the return type as std::set<T> and then pass std::string as the class template param. There are no errors in the class but only when I try to instantiate SetEvaluation<std::string> Can anyone shed light on this problem? thanks

    Read the article

  • limiting mysql results by range of a specific key INCLUDING DUPLICATES

    - by aVC
    I have a query SELECT p.*, m.*, (SELECT COUNT(*) FROM newPhotoonAlert n WHERE n.userIDfor='$id' AND n.threadID=p.threadID and n.seen='0') AS unReadCount FROM posts p JOIN myMembers m ON m.id = p.user_id LEFT JOIN following f ON (p.user_id = f.user_id AND f.follower_id='$id' AND f.request='0' AND f.status='1') JOIN myMembers searcher ON searcher.id = '$id' WHERE ((f.follower_id = searcher.id) OR m.id='$id') AND p.flagged <'5' ORDER BY p.threadID DESC,p.positionID It brings result as expected but I want to add Another CLAUSE to limit the results. Say a sample (minimal shown) set of data looks like this with the above query. threadID postID positionID url 564 1254 2 a.com 564 1245 1 a1.com 541 1215 3 b1.com 541 1212 2 b2.com 541 1210 1 b3.com 523 745 1 c1.com 435 689 2 d2.com 435 688 1 a4.com 256 345 1 s3.com 164 316 1 f1.com . . I want to get ROWS corresponding to 2 DISTINCT threadIDs starting from MAX, but I want to include duplicates as well. Something like AND p.threadID IN (Select just Two of all threadIDs currently selected, but include duplicate rows) So my result should be threadID postID positionID url 564 1254 2 a.com 564 1245 1 a1.com 541 1215 3 b1.com 541 1212 2 b2.com 541 1210 1 b3.com

    Read the article

  • Foreign-key-like merge in R

    - by skyl
    I'm merging a bunch of csv with 1 row per id/pk/seqn. > full = merge(demo, lab13am, by="seqn", all=TRUE) > full = merge(full, cdq, by="seqn", all=TRUE) > full = merge(full, mcq, by="seqn", all=TRUE) > full = merge(full, cfq, by="seqn", all=TRUE) > full = merge(full, diq, by="seqn", all=TRUE) > print(length(full$ridageyr)) [1] 9965 > print(summary(full$ridageyr)) Min. 1st Qu. Median Mean 3rd Qu. Max. 0.00 11.00 19.00 29.73 48.00 85.00 Everything is great. But, I have another file which has multiple rows per id like: "seqn","rxd030","rxd240b","nhcode","rxq250" 56,2,"","",NA,NA,"" 57,1,"ACETAMINOPHEN","01200",2 57,1,"BUDESONIDE","08800",1 58,1,"99999","",NA 57 has two rows. So, if I naively try to merge this file, I have a ton more rows and my data gets all skewed up. > full = merge(full, rxq, by="seqn", all=TRUE) > print(length(full$ridageyr)) [1] 15643 > print(summary(full$ridageyr)) Min. 1st Qu. Median Mean 3rd Qu. Max. 0.00 14.00 41.00 40.28 66.00 85.00 Is there a normal idiomatic way to deal with data like this? Suppose I want a way to make a simple model like MYSPECIAL_FACTOR <- somehow() glm(MYSPECIAL_FACTOR ~ full$ridageyr, family=binomial) where MYSPECIAL_FACTOR is, say, whether or not rxd240b == "ACETAMINOPHEN" for the observations which are unique by seqn. You can reproduce by running the first bit of this.

    Read the article

  • Ruby 1.9 regex as a hash key

    - by Liutauras
    I am trying this example myhash = {/(\d+)/ => "hello"} with ruby 1.9.2p136 (2010-12-25) [i386-mingw32]. It doesn't work as expected (edit: as it turned out it shouldn't work as I was expecting): irb(main):004:0> myhash = {/(\d+)/ => "hello"} => {/(\d+)/=>"Hello"} irb(main):005:0> myhash[2222] => nil irb(main):006:0> myhash["2222"] => nil In Rubular which is on ruby1.8.7 the regex works. What am I missing?

    Read the article

  • php array_filter without key preservation

    - by pistacchio
    Hi, if i filter an array with array_filter to eliminate null values, keys are preserved and this generated "holes" in the array. Eg: The filtered version of [0] => 'foo' [1] => null [2] => 'bar' is [0] => 'foo' [2] => 'bar' How can i get, instead [0] => 'foo' [1] => 'bar' ? Thanks

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 94 95 96 97 98 99 100 101 102 103 104 105  | Next Page >