Search Results

Search found 5644 results on 226 pages for 'unique constraints'.

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 26/226 | < Previous Page | 22 23 24 25 26 27 28 29 30 31 32 33  | Next Page >

  • Fastest way to compute a "Visual" checksum of an image

    - by ensnare
    I'm looking to create an ID system for cataloging images. I can't use md5() since that will change if I alter the EXIF tags of the image. I am currently using the SHA1 checksum computed by imagemagick. It works perfectly, but it's really, really slow on larger images (~15 seconds on a quad-core xeon for a 21 megapixel JPG). Are there any other "visual" methods of uniquely identifying an image that would be faster? Thank you.

    Read the article

  • Constraining enum value in method parameter

    - by fearofawhackplanet
    enum Fruit { Banana, Orange, Strawberry ... ... // etc, very long enum } PeelFruit(Fruit.Orange); PeelFruit(Fruit.Banana); PeelFruit(Fruit.Strawberry); // huh? can't peel strawberries! Sorry for the lame example, but hopefully you get the idea. Is there a way to constrain the enum values that PeelFruit will accept? Obvisouly I could check them in the method with a switch or something, but it would be cool if there was a way to do it that is a) a bit more compact, and b) would cause a compile time error, not a run time error. [Fruit = Orange,Bannana] void PeelFruit(Fruit fruit) { ... }

    Read the article

  • add Constraint on database with trigger

    - by Am1rr3zA
    Hi, I have 3 tables (Student, Course, student_course_choose(have field grade)) I defined a view on these 3 tables that get me an Average of the each student. I want to have constraint(with trigger) on these view(or on the table that need it) to limit the average of each student between 13 and 18. I somewhere read that I must use foreach statement(instead of foreach row) on trigger because when I decrease some grade of special student and his/her average become less than 13 they don't give me error (because later I increase grade of another his/her course ). how must I wrote this Trigger? (I want to implement aprh for testing trigger) note:I can write it in SQL server, oracle or Mysql no diff for me.

    Read the article

  • Using a check contraint in MySQL for controlling string length

    - by ptrn
    I'm tumbled with a problem! I've set up my first check constraint using MySQL, but unfortunately I'm having a problem. When inserting a row that should fail the test, the row is inserted anyway. The structure: CREATE TABLE user ( id INT UNSIGNED NOT NULL AUTO_INCREMENT, uname VARCHAR(10) NOT NULL, fname VARCHAR(50) NOT NULL, lname VARCHAR(50) NOT NULL, mail VARCHAR(50) NOT NULL, PRIMARY KEY (id), CHECK (LENGTH(fname) > 30) ); The insert statement: INSERT INTO user VALUES (null, 'user', 'Fname', 'Lname', '[email protected]'); The length of the string in the fname column should be too short, but it's inserted anyway. I'm pretty sure I'm missing something basic here.

    Read the article

  • How to declare a generic constraint that is a generic type

    - by HackedByChinese
    I have a two generic abstract types: Entity and Association. Let's say Entity looks like this: public class Entity<TId> { //... } and Association looks like this: public class Association<TEntity, TEntity2> { //... } How do I constrain Association so they can be of any Entity? I can accomplish it by the following: public class Association<TEntity, TId, TEntity2, TId2> where TEntity : Entity<TId> where TEntity2: Entity<TId2> { //... } This gets very tedious as more types derive from Association, because I have to keep passing down TId and TId2. Is there a simpler way to do this, besides just removing the constraint?

    Read the article

  • Grails: Property Null error

    - by richardhell
    I've a domain called Modulo with some properties and a Controller with a method that create a object from model and save it, when execute save the shell show this error: La propiedad [{0}] de la clase [{1}] no puede ser nulo But if i set the constraint nullable to true, the error show again. I think that i should not set this cosntraint. The model is linked to a mysql table with all properties except id allow null. I think I am not doing something wrong here. Any advice?? Domain: Modulo class Modulo { String nombre String icon String url //static constraint = { // url(nullable:true) //} } Controller: Example class ExampleController { def index = { def modulo = new Modulo( nombre:'xxx', icon:'xxx' ) if (modulo.save()){ println 'ok' }else{ modulo.errors.allErrors.each { println it.defaultMessage} } } } Thanks. José

    Read the article

  • SQL DROP TABLE foreign key constraint

    - by Polly Hollanger
    If I want to delete all the tables in my database like this, will it take care of the foreign key constraint? If not, how do I take care of that first? GO IF OBJECT_ID('dbo.[Course]','U') IS NOT NULL DROP TABLE dbo.[Course] GO IF OBJECT_ID('dbo.[Student]','U') IS NOT NULL DROP TABLE dbo.[Student]

    Read the article

  • After Trigger execute before constraint check in oracle

    - by satakare
    Hi, I have After Insert/Update trigger on Table T1 which get the referential data for Col1 from T2 and does some work and insert it into another table. The col1 is FK to Table T2. When user insert the incorrect or non existing value into the Col1 and if trigger is disabled I am getting constraint error that is fine. But when trigger is enabled and user insert the wrong value in Col1 trigger is getting fired and shows the 'no data found' error message. Actually I am expecting the table to throw constraint error, but trigger is throwing it. Please let me know your comments about this trigger behaviour.

    Read the article

  • Having constrains object to move X,Y at the same time?

    - by Hwang
    The stage is separated into 4 sections, and I will be moving the camera around the stage. So at each particular section the camera will have an area of constrain it can move. I mange to constrain its X & Y, but it could only navigate either X or Y. How to move in X+Y at the same time? if (mouseX>sec2maxX) { TweenLite.to(vC, 1, {x:sec2maxX}); } else if (mouseX<sec2minX) { TweenLite.to(vC, 1, {x:sec2minX}); } else { TweenLite.to(vC, 1, {x:mouseX}); } if (mouseY<sec2minY) { TweenLite.to(vC, 1, {y:sec2minY}); } else if (mouseY>sec2maxY) { TweenLite.to(vC, 1, {y:sec2maxY}); } else { TweenLite.to(vC, 1, {y:mouseY}); } if i were to put X & Y in a same line of code it would be a lot of possibilities when the mouse is on top left or right bottom kind of situation, so I need to have it running seperately, but how can I combine it so that it could move X+Y?

    Read the article

  • Can I constrain a route parameter to a certain type in ASP.net MVC?

    - by Paul Suart
    I have the following route: routes.MapRoute( "Search", // Route name "Search/{affiliateId}", // URL with parameters new { controller = "Syndication", action = "Search" } // Parameter defaults ); Is there a way I can ensure "affiliateId" is a valid Guid? I'm using MVCContrib elsewhere in my site and I'm fairly it provides a way to implement this kind of constraint.... I just don't know what it is!

    Read the article

  • Generic Type constraint in .net

    - by Jose
    Okay I'm looking for some input, I'm pretty sure this is not currently supported in .NET 3.5 but here goes. I want to require a generic type passed into my class to have a constructor like this: new(IDictionary<string,object>) so the class would look like this public MyClass<T> where T : new(IDictionary<string,object>) { T CreateObject(IDictionary<string,object> values) { return new T(values); } } But the compiler doesn't support this, it doesn't really know what I'm asking. Some of you might ask, why do you want to do this? Well I'm working on a pet project of an ORM so I get values from the DB and then create the object and load the values. I thought it would be cleaner to allow the object just create itself with the values I give it. As far as I can tell I have two options: 1) Use reflection(which I'm trying to avoid) to grab the PropertyInfo[] array and then use that to load the values. 2) require T to support an interface like so: public interface ILoadValues { void LoadValues(IDictionary values); } and then do this public MyClass<T> where T:new(),ILoadValues { T CreateObject(IDictionary<string,object> values) { T obj = new T(); obj.LoadValues(values); return obj; } } The problem I have with the interface I guess is philosophical, I don't really want to expose a public method for people to load the values. Using the constructor the idea was that if I had an object like this namespace DataSource.Data { public class User { protected internal User(IDictionary<string,object> values) { //Initialize } } } As long as the MyClass<T> was in the same assembly the constructor would be available. I personally think that the Type constraint in my opinion should ask (Do I have access to this constructor? I do, great!) Anyways any input is welcome.

    Read the article

  • Why is TRest in Tuple<T1... TRest> not constrained?

    - by Anthony Pegram
    In a Tuple, if you have more than 7 items, you can provide an 8th item that is another tuple and define up to 7 items, and then another tuple as the 8th and on and on down the line. However, there is no constraint on the 8th item at compile time. For example, this is legal code for the compiler: var tuple = new Tuple<int, int, int, int, int, int, int, double> (1, 1, 1, 1, 1, 1, 1, 1d); Even though the intellisense documentation says that TRest must be a Tuple. You do not get any error when writing or building the code, it does not manifest until runtime in the form of an ArgumentException. You can roughly implement a Tuple in a few minutes, complete with a Tuple-constrained 8th item. I just wonder why it was left off the current implementation? Is it possibly a forward-compatibility issue where they could add more elements with a hypothetical C# 5? Short version of rough implementation interface IMyTuple { } class MyTuple<T1> : IMyTuple { public T1 Item1 { get; private set; } public MyTuple(T1 item1) { Item1 = item1; } } class MyTuple<T1, T2> : MyTuple<T1> { public T2 Item2 { get; private set; } public MyTuple(T1 item1, T2 item2) : base(item1) { Item2 = item2; } } class MyTuple<T1, T2, TRest> : MyTuple<T1, T2> where TRest : IMyTuple { public TRest Rest { get; private set; } public MyTuple(T1 item1, T2 item2, TRest rest) : base(item1, item2) { Rest = rest; } } ... var mytuple = new MyTuple<int, int, MyTuple<int>>(1, 1, new MyTuple<int>(1)); // legal var mytuple2 = new MyTuple<int, int, int>(1, 2, 3); // illegal

    Read the article

  • [CODE GENERATION] How to generate DELETE statements in PL/SQL, based on the tables FK relations?

    - by The chicken in the kitchen
    Is it possible via script/tool to generate authomatically many delete statements based on the tables fk relations, using Oracle PL/SQL? In example: I have the table: CHICKEN (CHICKEN_CODE NUMBER) and there are 30 tables with fk references to its CHICKEN_CODE that I need to delete; there are also other 150 tables foreign-key-linked to that 30 tables that I need to delete first. Is there some tool/script PL/SQL that I can run in order to generate all the necessary delete statements based on the FK relations for me? (by the way, I know about cascade delete on the relations, but please pay attention: I CAN'T USE IT IN MY PRODUCTION DATABASE, because it's dangerous!) I'm using Oracle DataBase 10G R2. This is the result I've written, but it is not recursive: This is a view I have previously written, but of course it is not recursive! CREATE OR REPLACE FORCE VIEW RUN ( OWNER_1, CONSTRAINT_NAME_1, TABLE_NAME_1, TABLE_NAME, VINCOLO ) AS SELECT OWNER_1, CONSTRAINT_NAME_1, TABLE_NAME_1, TABLE_NAME, '(' || LTRIM ( EXTRACT (XMLAGG (XMLELEMENT ("x", ',' || COLUMN_NAME)), '/x/text()'), ',') || ')' VINCOLO FROM ( SELECT CON1.OWNER OWNER_1, CON1.TABLE_NAME TABLE_NAME_1, CON1.CONSTRAINT_NAME CONSTRAINT_NAME_1, CON1.DELETE_RULE, CON1.STATUS, CON.TABLE_NAME, CON.CONSTRAINT_NAME, COL.POSITION, COL.COLUMN_NAME FROM DBA_CONSTRAINTS CON, DBA_CONS_COLUMNS COL, DBA_CONSTRAINTS CON1 WHERE CON.OWNER = 'TABLE_OWNER' AND CON.TABLE_NAME = 'TABLE_OWNED' AND ( (CON.CONSTRAINT_TYPE = 'P') OR (CON.CONSTRAINT_TYPE = 'U')) AND COL.TABLE_NAME = CON1.TABLE_NAME AND COL.CONSTRAINT_NAME = CON1.CONSTRAINT_NAME --AND CON1.OWNER = CON.OWNER AND CON1.R_CONSTRAINT_NAME = CON.CONSTRAINT_NAME AND CON1.CONSTRAINT_TYPE = 'R' GROUP BY CON1.OWNER, CON1.TABLE_NAME, CON1.CONSTRAINT_NAME, CON1.DELETE_RULE, CON1.STATUS, CON.TABLE_NAME, CON.CONSTRAINT_NAME, COL.POSITION, COL.COLUMN_NAME) GROUP BY OWNER_1, CONSTRAINT_NAME_1, TABLE_NAME_1, TABLE_NAME; ... and it contains the error of using DBA_CONSTRAINTS instead of ALL_CONSTRAINTS...

    Read the article

  • Namespace constraint with generic class decleration

    - by SomeGuy
    Good afternoon people, I would like to know if (and if so how) it is possible to define a namespace as a constraint parameter in a generic class declaration. What I have is this: namespace MyProject.Models.Entities <-- Contains my classes to be persisted in db namespace MyProject.Tests.BaseTest <-- Obvious i think Now the decleration of my 'BaseTest' class looks like so; public class BaseTest<T> This BaseTest does little more (at the time of writing) than remove all entities that were added to the database during testing. So typically I will have a test class declared as: public class MyEntityRepositoryTest : BaseTest<MyEntity> What i would LIKE to do is something similar to the following: public class BaseTest<T> where T : <is of the MyProject.Models.Entities namespace> Now i am aware that it would be entirely possible to simply declare a 'BaseEntity' class from which all entities created within the MyProject.Models.Entities namespace will inherit from; public class BaseTest<T> where T : MyBaseEntity but...I dont actually need to, or want to. Plus I am using an ORM and mapping entities with inheritance, although possible, adds a layer of complexity that is not required. So, is it possible to constrain a generic class parameter to a namespace and not a specific type ? Thank you for your time.

    Read the article

  • I'm looking for a constraint to prevent the insert of an empty string in MySQL

    - by Marga Keuvelaar
    Ok, in this question I learned how to prevent the insert of a NULL value. But, unfortunately, an empty string is being inserted anyway. Apart from preventing this on the PHP side, I'd like to use something like a database constraint to prevent this. Of course a check on the application side is necessary, but I'd like it to be on both sides. I am taught that whatever application is talking to your database, it should not be able to insert basically wrong data in it. So... CREATE TABLE IF NOT EXISTS tblFoo ( foo_id int(11) NOT NULL AUTO_INCREMENT, foo_test varchar(50) NOT NULL, PRIMARY KEY (foo_id) ); Would still allow me to do this insert: INSERT INTO tblFoo (foo_test) VALUES (''); Which I would like to prevent.

    Read the article

  • XForms relation of 'constraint' and 'required' properties

    - by Danny
    As a reference, the most similar question already asked is: http://stackoverflow.com/questions/8667849/making-xforms-enforce-the-constraint-and-type-model-item-properties-only-when-fi The difference is that I cannot use the relevant properties since I do want the field to be visible and accessible. I'm attempting to make a XForms form that has the following properties: It displays a text field named 'information'. (for the example) This field must not be required, since it may not be necessary to enter data. (Or this data will be entered at a later time.) However, if data is entered in this field, it must adhere to the specified constraint. I cannot mark the field as not relevant since this would hide the field and some data may need to be entered in it. The trouble now is that even though the field has no data in it, the constraint is still enforced (i.e. even though it is not marked as 'required'). I have taken a look at the XForms 1.1 specification, however it does not seem to describe how the properties 'required' and 'constraint' should interact. The only option I see, is to add a part to the constraint such that an empty value is allowed. e.g.: . = '' or <actual-constraint However, I don't like this. It feels like a workaround to add this to every such field. Is there any other way to express that non-required fields should not need to match the constraint for that field? (Am I missing something?)

    Read the article

  • MySQL Removing Some Foreign keys

    - by Drew
    I have a table whose primary key is used in several other tables and has several foreign keys to other tables. CREATE TABLE location ( locationID INT NOT NULL AUTO_INCREMENT PRIMARY KEY ... ) ENGINE = InnoDB; CREATE TABLE assignment ( assignmentID INT NOT NULL AUTO_INCREMENT PRIMARY KEY, locationID INT NOT NULL, FOREIGN KEY locationIDX (locationID) REFERENCES location (locationID) ... ) ENGINE = InnoDB; CREATE TABLE assignmentStuff ( ... assignmentID INT NOT NULL, FOREIGN KEY assignmentIDX (assignmentID) REFERENCES assignment (assignmentID) ) ENGINE = InnoDB; The problem is that when I'm trying to drop one of the foreign key columns (ie locationIDX) it gives me an "ERROR 1025 (HY000): Error on rename" error. How can I drop the column in the assignment table above without getting this error?

    Read the article

  • Rand(); with exclusion to and already randomly generated number..?

    - by Stefan
    Hey, I have a function which calls a users associated users from a table. The function then uses the rand(); function to chose from the array 5 randomly selected userID's however!... In the case where a user doesnt have many associated users but above the min (if below the 5 it just returns the array as it is) then it gives bad results due to repeat rand numbers... How can overcome this or exclude a previously selected rand number from the next rand(); function call. Here is the section of code doing the work. Bare in mind this must be highly efficient as this script is used everywhere. $size = sizeof($users)-1; $nusers[0] = $users[rand(0,$size)]; $nusers[1] = $users[rand(0,$size)]; $nusers[2] = $users[rand(0,$size)]; $nusers[3] = $users[rand(0,$size)]; $nusers[4] = $users[rand(0,$size)]; return $nusers; Thanks in advance! Stefan

    Read the article

  • iPhone: Create a single UIView from multiple clicks

    - by Cuzog
    I'm making a partial overlay modal in my app with the code from “Semi-Modal (Transparent) Dialogs on the iPhone” at ramin.firoozye.com. In doing so, the button that calls the modal is still visible and clickable. I will hide this button when the modal spawns, but I want to be sure if the user clicks very quickly twice, a new modal doesn't come up for each click. What is the best way to check that the modal doesn't already exist when calling it from the button click? You can download the test project here. For those that don't have xcode, the relevant functions are below: I call forth the modal on button click with this: - (IBAction)displayModal:(id)sender { ModalViewController *modalController = [[ModalViewController alloc] initWithNibName:@"ModalViewController" bundle:nil]; modalController.view.frame = CGRectOffset(modalController.view.frame, 0, 230); [self showModal:modalController.view]; } Then use this function to animate the custom modal over the current view: - (void)showModal:(UIView*) modalView { UIWindow* mainWindow = (((TestAppDelegate*) [UIApplication sharedApplication].delegate).window); CGPoint middleCenter = modalView.center; CGSize offSize = [UIScreen mainScreen].bounds.size; CGPoint offScreenCenter = CGPointMake(offSize.width / 2.0, offSize.height * 1.5); modalView.center = offScreenCenter; // we start off-screen [mainWindow addSubview:modalView]; // Show it with a transition effect [UIView beginAnimations:nil context:nil]; [UIView setAnimationDuration:0.4]; // animation duration in seconds modalView.center = middleCenter; [UIView commitAnimations]; } Then I dismiss the modal on button click with this: - (IBAction)dismissModal:(id)sender { [self hideModal:self.view]; } And then use these functions to animate the modal offscreen and clean itself up: - (void)hideModal:(UIView*) modalView { CGSize offSize = [UIScreen mainScreen].bounds.size; CGPoint offScreenCenter = CGPointMake(offSize.width / 2.0, offSize.height * 1.5); [UIView beginAnimations:nil context:modalView]; [UIView setAnimationDuration:0.7]; [UIView setAnimationDelegate:self]; [UIView setAnimationDidStopSelector:@selector(hideModalEnded:finished:context:)]; modalView.center = offScreenCenter; [UIView commitAnimations]; } - (void)hideModalEnded:(NSString *)animationID finished:(NSNumber *)finished context:(void *)context { UIView* modalView = (UIView *)context; [modalView removeFromSuperview]; [self release]; } Any help is greatly appreciated!

    Read the article

  • Uniquing with Existing Core Data Entities

    - by warrenm
    I'm using Core Data to store a lot (1000s) of items. A pair of properties on each item are used to determine uniqueness, so when a new item comes in, I compare it against the existing items before inserting it. Since the incoming data is in the form of an RSS feed, there are often many duplicates, and the cost of the uniquing step is O(N^2), which has become significant. Right now, I create a set of existing items before iterating over the list of (possible) new items. My theory is that on the first iteration, all the items will be faulted in, and assuming we aren't pressed for memory, most of those items will remain resident over the course of the iteration. I see my options thusly: Use string comparison for uniquing, iterating over all "new" items and comparing to all existing items (Current approach) Use a predicate to filter the set of existing items against the properties of the "new" items. Use a predicate with Core Data to determine uniqueness of each "new" item (without retrieving the set of existing items). Is option 3 likely to be faster than my current approach? Do you know of a better way?

    Read the article

  • Check constraint over two columns

    - by Rippo
    I want to add a Check Constraint to a table for server 2005 but cannot work it out. MemberId ClubId MeetingId 1 100 10 2 100 10 3 100 10 7 101 10 <-This would throw a check constraint 1 100 11 2 100 11 I do not want to have more than one ClubId for a single MeetingId Basically a ClubId can only belong to a single MeetingId but can have more than one member assigned. How do I achieve this?

    Read the article

  • Do I need to write a trigger for such a simple constraint?

    - by Paul Hanbury
    I really had a hard time knowing what words to put into the title of my question, as I am not especially sure if there is a database pattern related to my problem. I will try to simplify matters as much as possible to get directly to the heart of the issue. Suppose I have some tables. The first one is a list of widget types: create table widget_types ( widget_type_id number(7,0) primary key, description varchar2(50) ); The next one contains icons: create table icons ( icon_id number(7,0) primary key, picture blob ); Even though the users get to select their preferred widget, there is a predefined subset of widgets that they can choose from for each widget type. create table icon_associations ( widget_type_id number(7,0) references widget_types, icon_id number(7,0) references icons, primary key (widget_type_id, icon_id) ); create table icon_prefs ( user_id number(7,0) references users, widget_type_id number(7,0), icon_id number(7,0), primary key (user_id, widget_type_id), foreign key (widget_type_id, icon_id) references icon_associations ); Pretty simple so far. Let us now assume that if we are displaying an icon to a user who has not set up his preferences, we choose one of the appropriate images associated with the current widget. I'd like to specify the preferred icon to display in such a case, and here's where I run into my problem: alter table icon_associations add ( is_preferred char(1) check( is_preferred in ('y','n') ) ) ; I do not see how I can enforce that for each widget_type there is one, and only one, row having is_preferred set to 'y'. I know that in MySQL, I am able to write a subquery in my check constraint to quickly resolve this issue. This is not possible with Oracle. Is my mistake that this column has no business being in the icon_associations table? If not where should it go? Is this a case where, in Oracle, the constraint can only be handled with a trigger? I ask only because I'd like to go the constraint route if at all possible. Thanks so much for your help, Paul

    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 | 22 23 24 25 26 27 28 29 30 31 32 33  | Next Page >