Search Results

Search found 24879 results on 996 pages for 'prime number'.

Page 262/996 | < Previous Page | 258 259 260 261 262 263 264 265 266 267 268 269  | Next Page >

  • Do we need Record Level Locking when we already have Transaction for online ordering? (of concert ti

    - by Jian Lin
    For online ordering of concert seat or airline ticket, do we need Record Level Locking or is Transaction good enough? For concert ticket (say, seat Number 20B), or airline ticket (even with overbooking, the limit is 210, for example), I think the website cannot lock any record or begin transaction when showing the ticket purchase screen. But after the user clicks "Confirm Purchase", then the server should Begin a Transaction, Purchase Seat Number 20B, and try to Commit. If another user already bought Seat 20B in a previous transaction, then it is the "Commit" part that the current transaction will fail? So... we don't need Record Level Locking? Do Transactions always go serialized (one after another), so that's why we can know for sure there is no "race condition"? In what situation is Record Level Locking needed then?

    Read the article

  • How do we know the correct moves of Tower of Hanoi?

    - by Saqib
    We know that: In case of iterative solution: Alternating between the smallest and the next-smallest disks, follow the steps for the appropriate case: For an even number of disks: make the legal move between pegs A and B make the legal move between pegs A and C make the legal move between pegs B and C repeat until complete For an odd number of disks: make the legal move between pegs A and C make the legal move between pegs A and B make the legal move between pegs B and C repeat until complete In case of recursive solution: To move n discs from peg A to peg C: move n-1 discs from A to B. This leaves disc n alone on peg A move disc n from A to C move n-1 discs from B to C so they sit on disc n Now the questions are: How did we get this two solutions? Only by intuition? Or by logical/mathematical computation? If computation, how?

    Read the article

  • In Python, how to use a C++ function which returns an allocated array of structs via a ** parameter?

    - by Jon-Eric
    I'd like to use some existing C++ code, NvTriStrip, in a Python tool. SWIG easily handles the functions with simple parameters, but the main function, GenerateStrips, is much more complicated. What do I need to put in the SWIG interface file to indicate that primGroups is really an output parameter and that it must be cleaned up with delete[]? /////////////////////////////////////////////////////////////////////////// // GenerateStrips() // // in_indices: input index list, the indices you would use to render // in_numIndices: number of entries in in_indices // primGroups: array of optimized/stripified PrimitiveGroups // numGroups: number of groups returned // // Be sure to call delete[] on the returned primGroups to avoid leaking mem // bool GenerateStrips( const unsigned short* in_indices, const unsigned int in_numIndices, PrimitiveGroup** primGroups, unsigned short* numGroups, bool validateEnabled = false ); FYI, here is the PrimitiveGroup declaration: enum PrimType { PT_LIST, PT_STRIP, PT_FAN }; struct PrimitiveGroup { PrimType type; unsigned int numIndices; unsigned short* indices; PrimitiveGroup() : type(PT_STRIP), numIndices(0), indices(NULL) {} ~PrimitiveGroup() { if(indices) delete[] indices; indices = NULL; } };

    Read the article

  • Sorting a list of variable length integers delimited by decimal points...

    - by brewerdc
    Hey guys, I'm in need of some help. I have a list of delimited integer values that I need to sort. An example: Typical (alpha?) sort: 1.1.32.22 11.2.4 2.1.3.4 2.11.23.1.2 2.3.7 3.12.3.5 Correct (numerical) sort: 1.1.32.22 2.1.3.4 2.3.7 2.11.23.1.2 3.12.3.5 11.2.4 I'm having trouble figuring out how to setup the algorithm to do such a sort with n number of decimal delimiters and m number of integer fields. Any ideas? This has to have been done before. Let me know if you need more information. Thanks a bunch! -Daniel

    Read the article

  • Check if row already exists, if so tell the referenced table the id

    - by flhe
    Let's assume I have a table magazine: CREATE TABLE magazine ( magazine_id integer NOT NULL DEFAULT nextval(('public.magazine_magazine_id_seq'::text)::regclass), longname character varying(1000), shortname character varying(200), issn character varying(9), CONSTRAINT pk_magazine PRIMARY KEY (magazine_id) ); And another table issue: CREATE TABLE issue ( issue_id integer NOT NULL DEFAULT nextval(('public.issue_issue_id_seq'::text)::regclass), number integer, year integer, volume integer, fk_magazine_id integer, CONSTRAINT pk_issue PRIMARY KEY (issue_id), CONSTRAINT fk_magazine_id FOREIGN KEY (fk_magazine_id) REFERENCES magazine (magazine_id) MATCH SIMPLE ON UPDATE NO ACTION ON DELETE NO ACTION ); Current INSERTS: INSERT INTO magazine (longname,shotname,issn) VALUES ('a long name','ee','1111-2222'); INSERT INTO issue (fk_magazine_id,number,year,volume) VALUES (currval('magazine_magazine_id_seq'),'8','1982','6'); Now a row should only be inserted into 'magazine', if it does not already exist. However if it exists, the table 'issue' needs to get the 'magazine_id' of the row that already exists in order to establish the reference. How can i do this? Thx in advance!

    Read the article

  • controlling bluetooth connection in matlab

    - by Mehreen Shahid
    we have a project in which we have to pick randomly generated numbers from a remote device, say mobile. there is a simple java application to generate numbers. next, we have to recieve those numbers in our matlab program via bluetooth connection with the device. assuming those numbers are temperature readings, we want to recieve a new number after every 10 sec and display the number on our matlab GUI program. the problem is do we implement bluetooth protocol through our programming? or use the matlab templates? because otherwise whenever we want to transfer file from a mobile to computer, we have to manually click "recieve a file" in blutooth wizard , just like we normally do to transfer a file. we want to enable the connection once, and then recieve text files after every 10 seconds to be read in our matlab program. can anyone please tell is it even possible in matlab? if yes, how do we establish such an automatic real time connection?

    Read the article

  • How can I write cocoa bindings as code instead of in the Interface Builder?

    - by johnjohndoe
    In my modell got an NSMutableArray that keeps track of a changing number of elements. In my view I got a NSTextField that shows the number of elements. The view gots unarchived from the nib file and alloc/inits the modell. Therefore it knowns about the modell and the contained array. I established the connection as follows. In the Interface Builder at the textfield I added a Cocoa Binding "path" like this: myModell.myArray.@count. By this I can access the count property (which is a must since the array itself does not change). The binding is based on key-value compliance which I established at the modell so the array can be accessed. But key-value compliance is not part of the questions. My question: How can I put the binding into the sourcecode and not writing it into the Interface Builder?

    Read the article

  • How to create list of numbers and append its reverse to it efficiently in Ruby

    - by Kiwi
    Given a minimum integer and maximum integer, I want to create an array which counts from the minimum to the maximum by two, then back down (again by two, repeating the maximum number). For example, if the minimum number is 1 and the maximum is 9, I want [1, 3, 5, 7, 9, 9, 7, 5, 3, 1]. I'm trying to be as concise as possible, which is why I'm using one-liners. In Python, I would do this: range(1, 10, 2) + range(9, 0, -2) In Ruby, which I'm just beginning to learn, all I've come up with so far is: (1..9).inject([]) { |r, num| num%2 == 1 ? r << num : r }.reverse.inject([]) { |r, num| r.unshift(num).push(num) } Which works, but I know there must be a better way. What is it?

    Read the article

  • How would you create a string of all UTF-8 characters? [PHP]

    - by Xeoncross
    There are many ways to represent the +1 million UTF-8 characters. Take the latin capital "A" with macron (A). This is unicode code point U+0100, hex number 0xc4 0x80, decimal number 196 128, and binary 11000100 10000000. I would like to create a collection of the first 65,535 UTF-8 characters for use in testing applications. These are all unicode characters up to code point U+FFFF (byte3). Is it possible to do something like a for($x=0) loop and then convert the resulting decimal to another base (like hex) which would allow the creation of the matching unicode character? I can create the value A using something like this: $char = "\xc4\x80"; // or $char = chr(196).chr(128); However, I am not sure how to turn this into an automated process. // fail! $char = "\x". dechex($a). "\x". dexhex($$b);

    Read the article

  • Basic Conditional Checking for IF statements in C

    - by ZaZu
    Hi there, Can someone please explain what really goes on in this code ? If I put the AND statement, the message wont show if values are less than 0 or greater than 10 ... I think I must use 1 0 logic to work this out right ? I just need someone to briefly explain it please. #include<stdio.h> main(){ puts("enter number"); scanf("%d",num); if(num<0 || num >10) puts("yay"); } How is that IF statement different when AND is put : #include<stdio.h> main(){ puts("enter number"); scanf("%d",num); if(num<0 && num >10) puts("yay"); } Thanks !!

    Read the article

  • Maven 2: How to package current project version in a WAR file?

    - by Tom van Zummeren
    I am using Maven 2 to build my Java project and I am looking for a way to present the current version number of the pom.xml to the user (using a Servlet or JSP for example). As far as I can see, the best way would be that Maven packages the version number as a text file into the WAR. This allows me to read the version from that file and present it the way I want. Does anyone know of a plugin that can do something like that for me? Maybe the WAR plugin can be configured to do so? Or maybe using some other approach all together?

    Read the article

  • Array basics - Populating with loop

    - by madlan
    Hi, I'm looping through a zip file trying to add the file name of each file within. Is this the correct method? Dim ZipNameArray(?) Using zip As ZipFile = ZipFile.Read(ZipToUnpack) For Each file In zip ZipNameArray(?) = file .FileName Next End Using I do not know the array size until I start looping through the zip (To work out the number of files within). How do I increment the Array? file is not a number? (It's a ZipEntry)

    Read the article

  • Alter Regular Expression to Return 2 Values Instead of 3 from userAgent String

    - by Jay
    I've taken a regular expression from jQuery to detect if a browser's engine is WebKit and gets it's version number, it returns 3 values extracted from the userAgent string: webkit/….…, webkit and ….… [“….…” being the version number]. I would like the regular expression to return just 2 values: webkit and ….…. I'm rubbish at regular expressions, so please can you give an explanation of the expression with your answer. The regular expression I'm currently working with and wish to improve is: /(webkit)[\/]([\w.]+)/. I appreciate all your help, thanks in advance!

    Read the article

  • How to retrieve row count of one-to-many relation while also include original entity?

    - by kaa
    Say I have two entities Foo and Bar where Foo has-many Bar's, class Foo { int ImportantNumber { get; set; } IEnumerable<Bar> Bars { get; set; } } class FooDTO { Foo Foo { get; set; } int BarCount { get; set; } } How can I efficiently sum up the number of Bars per Foo in a DTO using a single query, preferrably only with the Criteria interface. I have tried any number of ways to get the original entity out of a query with ´SetProjection´ but no luck. The current theory is to do something like SELECT Foo.*, BarCounts.counts FROM Foo LEFT JOIN ( SELECT fooId, COUNT(*) as counts FROM Bar GROUP BY fooId ) AS BarCounts ON Foo.id=BarCounts.fooId but with Criterias, and I just can't seem to figure out how.

    Read the article

  • Bit Flipping in Hex

    - by freyrs
    I have an 8 digit hexadecimal number of which I need certain digits to be either 0 or f. Given the specific place of the digits is there a quick way to generate the hex number with those places "flipped" to f. For example: flip_digits(1) = 0x000000f flip_digits(1,2,4) = 0x0000f0ff flip_digits(1,7,8) = 0xff00000f I'm doing this on an embedded device so I can't call any math libraries, I suspect it can be done with just bit shifts but I can't quite figure out the method. Any sort of solution (Python, C, Pseudocode) will work. Thanks in advance.

    Read the article

  • devise register confirmation

    - by mattherick
    hello! i have a user and an admin role in my project. i created my authentification with devise, really nice and goot tool for handling the authentification. in my admin role i don´t have any confirmation or something like that. it is really simple and doesn´t make problems. but in my user model i have following things: model: devise :database_authenticatable, :confirmable, :recoverable, :rememberable, :trackable, :validatable, :timeoutable, :registerable # Setup accessible (or protected) attributes for your model attr_accessible :email, :username, :prename, :surname, :phone, :street, :number, :location, :password, :password_confirmation and few validations, but they aren´t relevant this time. my migration looks like following one: class DeviseCreateUsers < ActiveRecord::Migration def self.up create_table(:users) do |t| t.database_authenticatable :null = false t.confirmable t.recoverable t.rememberable t.trackable t.timeoutable t.validateable t.string :username t.string :prename t.string :surname t.string :phone t.string :street t.integer :number t.string :location t.timestamps end add_index :users, :email, :unique => true add_index :users, :confirmation_token, :unique => true add_index :users, :reset_password_token, :unique => true add_index :users, :username, :unique => true add_index :users, :prename, :unique => false add_index :users, :surname, :unique => false add_index :users, :phone, :unique => false add_index :users, :street, :unique => false add_index :users, :number, :unique => false add_index :users, :location, :unique => false end def self.down drop_table :users end end into my route.rb I added following statements: map.devise_for :admins map.devise_for :users, :path_names = { :sign_up = "register", :sign_in = "login" } map.root :controller = "main" and now my problem.. if I register a new user, I fill in all my data in the register form and submit it. After that I get redirected to the controller main with the flash-notice "You have signed up successfully." And I am logged in. But I don´t want to be logged in, because I don´t have confirmed my new user account yet. If I open the console I see the last things in the logs and there I see the confirmation-mail and the text and all stuff, but I am already logged in... I can´t explain why, ... does somebody of you have an idea? If I copy out the confirmation-token from the logs and confirm my account, I can log in, but if I don´t confirm, I also can log in..

    Read the article

  • Checking for uppercase/lowercase/numbers with Jquery

    - by user1725794
    Either I'm being really retarded here or its just the lack of sleep but why doesn't this work? If I use the "or" operator it works for each separate test but as soon as it change it to the "and" operator it stops working. I'm trying to test the password input of a form to see if its contains lowercase, uppercase and at least 1 number of symbol. I'm having a lot of trouble with this so help would be lovely, here is the code I have. var upperCase= new RegExp('[^A-Z]'); var lowerCase= new RegExp('[^a-z]'); var numbers = new RegExp('[^0-9]'); if(!$(this).val().match(upperCase) && !$(this).val().match(lowerCase) && !$(this).val().match(numbers)) { $("#passwordErrorMsg").html("Your password must be between 6 and 20 characters. It must contain a mixture of upper and lower case letters, and at least one number or symbol."); } else { $("#passwordErrorMsg").html("OK") }

    Read the article

  • extension method phone format with country code as parameter

    - by frenchie
    Hi, I'm writing an extension method called ToPhoneFormat that formats a string of digits to phone numbers. Is it possible to add a parameter to the method that would enable me to call it like this: MyPhoneString.ToPhoneFormat(international code) That way, I could write MyPhoneString.ToPhoneFormat(1); to format a US phone number and MyPhoneString.ToPhoneFormat(33) to format a French phone number. I already wrote the method that does the formatting but I'm wondering how to build the constructor so that it works with a parameter when I'm calling it. Thanks.

    Read the article

  • DB Design Pattern - Many to many classification / categorised tagging.

    - by Robin Day
    I have an existing database design that stores Job Vacancies. The "Vacancy" table has a number of fixed fields across all clients, such as "Title", "Description", "Salary range". There is an EAV design for "Custom" fields that the Clients can setup themselves, such as, "Manager Name", "Working Hours". The field names are stored in a "ClientText" table and the data stored in a "VacancyClientText" table with VacancyId, ClientTextId and Value. Lastly there is a many to many EAV design for custom tagging / categorising the vacancies with things such as Locations/Offices the vacancy is in, a list of skills required. This is stored as a "ClientCategory" table listing the types of tag, "Locations, Skills", a "ClientCategoryItem" table listing the valid values for each Category, e.g., "London,Paris,New York,Rome", "C#,VB,PHP,Python". Finally there is a "VacancyClientCategoryItem" table with VacancyId and ClientCategoryItemId for each of the selected items for the vacancy. There are no limits to the number of custom fields or custom categories that the client can add. I am now designing a new system that is very similar to the existing system, however, I have the ability to restrict the number of custom fields a Client can have and it's being built from scratch so I have no legacy issues to deal with. For the Custom Fields my solution is simple, I have 5 additional columns on the Vacancy Table called CustomField1-5. This removes one of the EAV designs. It is with the tagging / categorising design that I am struggling. If I limit a client to having 5 categories / types of tag. Should I create 5 tables listing the possible values "CustomCategoryItems1-5" and then an additional 5 many to many tables "VacancyCustomCategoryItem1-5" This would result in 10 tables performing the same storage as the three tables in the existing system. Also, should (heaven forbid) the requirements change in that I need 6 custom categories rather than 5 then this will result in a lot of code change. Therefore, can anyone suggest any DB Design Patterns that would be more suitable to storing such data. I'm happy to stick with the EAV approach, however, the existing system has come across all the usual performance issues and complex queries associated with such a design. Any advice / suggestions are much appreciated. The DBMS system used is SQL Server 2005, however, 2008 is an option if required for any particular pattern.

    Read the article

  • SQL LEFT JOIN help

    - by Stolz
    My scenario: There are 3 tables for storing tv show information; season, episode and episode_translation. My data: There are 3 seasons, with 3 episodes each one, but there is only translation for one episode. My objetive: I want to get a list of all the seasons and episodes for a show. If there is a translation available in a specified language, show it, otherwise show null. My attempt to get serie 1 information in language 1: SELECT season_number AS season,number AS episode,name FROM season NATURAL JOIN episode NATURAL LEFT JOIN episode_trans WHERE id_serie=1 AND id_lang=1 ORDER BY season_number,number result: +--------+---------+--------------------------------+ | season | episode | name | +--------+---------+--------------------------------+ | 3 | 3 | Episode translated into lang 1 | +--------+---------+--------------------------------+ expected result +-----------------+--------------------------------+ | season | episode| name | +-----------------+--------------------------------+ | 1 | 1 | NULL | | 1 | 2 | NULL | | 1 | 3 | NULL | | 2 | 1 | NULL | | 2 | 2 | NULL | | 2 | 3 | NULL | | 3 | 1 | NULL | | 3 | 2 | NULL | | 3 | 3 | Episode translated into lang 1 | +--------+--------+--------------------------------+ Full DB dump http://pastebin.com/Y8yXNHrH

    Read the article

  • Hibernate: getting a record but it's being updated in the database?

    - by jack
    For some reason Hibernate seems to be keeping my session open and updating the object without me explicitely invoking a save/update/saveorupdate. I guess the session is staying open and it's beeing marked as dirty. However this is not the desired behaviour, so what's the cleanest way to fix this? The issue seems to occur because I store a phone number without formatting in the database but the getter of the object returns a formatted telephone number. My flow: go to a jsp = controller = service = dao DAO getter function if(userId != 0) { return (User)dbFactory.get(User.class, userId); } return null; The service just passes it to the controller and the controller puts te User object in the request scope. I display it on my JSP page using EL.

    Read the article

  • How would I design this table in SQL?

    - by RSharma
    I have a parent master table that is generic enough to hold the common information of the children. Since the children were substantially different, we created separate tables for them. So I have something like this: tblMaster -------- MasterID int Name varchar(50) --Common to all children and there are a bunch of fields like this ChildType int -- Type of Child either ChildOne or ChildTwo ChildID int -- need to store ChildOneID or ChildTwoID depending on type of Child, so that i can refer to children tblChild1 -------- ChildOneID int IDENTITY tblChild2 --------- ChildTwoID int IDENTITY Should I have a ChildID in the master that is either ChildOneID or ChildTwoID based on the ChildType column? I have a number of children and I have simplified it for this question. The other way is to add ChildOneID and ChildTwoID as columns in the master, but since i have a number of columns, I will have a lot of null columns EDIT: Any help is appreciated

    Read the article

  • MS SQL Server 2000 tables

    - by klork
    We currently have an MS SQL Server 2000 database with one table containing data for multiple users. The data is keyed by memberid which is an integer field. The table has a clustered index on memberid. The table is now about 200 million rows. Indexing and maintenance are becoming issues. We are debating splitting the table into one table per user model. This would imply that we would end up with a very large number of tables potentially upto the 2,147,483,647, considering just positive values. My questions: 1) Does anyone have any experience with a MS SQL Server (2000/2005) installation with millions of tables? 2) What are the implications of this architecture with regards to maintenance and access using Query Analyzer, Enterprise Manager etc. 3) What are the implications to having such a large number of indexes in a database instance. All comments are appreciated. Thanks

    Read the article

  • Get command object

    - by user198147
    Hi all, I am writing a spring 2.5 application and in my jsp I'm writing my own tags. It's about a list of objects...when I change the number of rows that list shows(a combobox), I am doing a submit on my form returning back to the view(obviosly with the new number of rows returned). When listing with my own tags I need to get the properties from my command object. I have access to the pageContext object but I can't figure where the command object is stored. Could someoane please help me? Thanks in advance, Luisa

    Read the article

< Previous Page | 258 259 260 261 262 263 264 265 266 267 268 269  | Next Page >