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  • Arrays in database tables and normalization

    - by Ivan Petrov
    Hi! Is it smart to keep arrays in table columns? More precisely I am thinking of the following schema which to my understanding violates normalization: create table Permissions( GroupID int not null default(-1), CategoryID int not null default(-1), Permissions varchar(max) not null default(''), constraint PK_GroupCategory primary key clustered(GroupID,CategoryID) ); and this: create table Permissions( GroupID int not null default(-1), CategoryID int not null default(-1), PermissionID int not null default(-1), constraint PK_GroupCategory primary key clustered(GroupID,CategoryID) ); UPD: Forgot to mention, in the scope of this concrete question we will consider that the "fetch rows that have permission X" won't be performed, instead all the lookups will be made by GroupID and CategoryID only Thoughts? Thanks in advance!

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  • 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

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  • How to do "See Also" to a book using doxygen

    - by Paul J. Lucas
    The Javadoc @see allows a simple string as an argument to refer to something like a book, e.g.: @see "The Java Programming Language." As far as I can tell, the Doxygen \see offers no equivalent. Is there any way to have a book reference generated in the documentation, e.g.: See Also The C++ Programming Language, Bjarne Stroustrup, Addison-Wesley, 2000, section 19.4.1: The Standard Allocator ? Clarification This question is about how to do a "See Also" as part of a comment, e.g.: /** * Allocates memory in an amazing way. * \param size The number of bytes to allocate. * \return Returns a pointer to the start of the allocated memory. * \see MyOtherClass::alloc() * \see "The C++ Programming Language," Bjarne Stroustrup, Addison-Wesley, 2000, * section 19.4.1: The Standard Allocator. */ void* my_alloc( size_t size ); Of course the above does not work in Doxygen. Note that if there are multiple \see tags, they should be merged into a single "See Also" section (like the way \see normally works.

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  • How to use a variable to specify filegroup in MSSQL

    - by gt
    I want to alter a table to add a constraint during upgrade on a MSSQL database. This table is normally indexed on a filegroup called 'MY_INDEX' - but may also be on a database without this filegroup. In this case I want the indexing to be done on the 'PRIMARY' filegroup. I tried the following code to achieve this: DECLARE @fgName AS VARCHAR(10) SET @fgName = CASE WHEN EXISTS(SELECT groupname FROM sysfilegroups WHERE groupname = 'MY_INDEX') THEN QUOTENAME('MY_INDEX') ELSE QUOTENAME('PRIMARY') END ALTER TABLE [dbo].[mytable] ADD CONSTRAINT [PK_mytable] PRIMARY KEY ( [myGuid] ASC ) ON @fgName -- fails: 'incorrect syntax' However, the last line fails as it appears a filegroup cannot be specified by variable. Is this possible?

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  • SQL Server 2005 drop column with constraints

    - by Julien N
    Hi ! In Sql Server 2005 I have a column with a "DEFAULT" constraint. I'd like to create a script that drops that column. The problem is that is returns me that error : Msg 5074, Level 16, State 1, Line 1 The object 'DF__PeriodSce__IsClo__4BCC3ABA' is dependent on column 'IsClosed'. Msg 4922, Level 16, State 9, Line 1 ALTER TABLE DROP COLUMN IsClosed failed because one or more objects access this column. I couldn't find an easy way to drop a column and all its associated constraints (only found big scripts that look into system table... there MUST (!!) be a "nice" way to do that !). And as the DEFAULT constraint's name has been randomly generated, I can't drop it by name. Thanks for your help.

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  • How to use a variable to specify filegroup in SQL Server

    - by gt
    I want to alter a table to add a constraint during upgrade on a SQL Server database. This table is normally indexed on a filegroup called 'MY_INDEX' - but may also be on a database without this filegroup. In this case I want the indexing to be done on the 'PRIMARY' filegroup. I tried the following code to achieve this: DECLARE @fgName AS VARCHAR(10) SET @fgName = CASE WHEN EXISTS(SELECT groupname FROM sysfilegroups WHERE groupname = 'MY_INDEX') THEN QUOTENAME('MY_INDEX') ELSE QUOTENAME('PRIMARY') END ALTER TABLE [dbo].[mytable] ADD CONSTRAINT [PK_mytable] PRIMARY KEY ( [myGuid] ASC ) ON @fgName -- fails: 'incorrect syntax' However, the last line fails as it appears a filegroup cannot be specified by variable. Is this possible?

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  • Pomodoro technique & other ways to increase personal productivity

    - by Jayson
    I recently came across the Pomodoro Technique as a way to increase productivity, get in the zone, and in general feel a sense of accomplishment at setting some short programming goals and achieving them. So far I have enjoyed it and the sense of accomplishment I get after seeing a bunch of short goals add up at the end of the day to a lot of work done on a programming project. What other ideas, similar or not, add a little variety to achieving goals, personal productivity, get in the programming zone, and so forth? What ideas or techniques are expressed formally, such as those in the Pomodoro paper, rather than trite maxims?

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  • forcing Management Studio to use alter table instead of drop/recreate

    - by marco
    Hi! I'm wondering if is there a way to force MSSQL Management Studio to produce a script like this: ALTER TABLE Mytable ADD MyCol bit NOT NULL CONSTRAINT MyColDefault DEFAULT 0 WITH VALUES ALTER TABLE [dbo].Mytable ALTER COLUMN MyCol2 int NULL GO when I alter a very simple property of a column on a table. If I do this in the designer and ask for the produced script, the script doesn't do such simple tasks, but instead copies all the data in a tmp table, drops the original table, renames the tmp table with the original table name. And, of course, drops and recreates every constraint and relationships. Is there any option I can change to change this behaviour? Or, this may be possible, is there some danger I don't see in using the simple ALTER TABLE above? thanks.

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  • Vim Editor is very smart?

    - by Narek
    I am programming in C++ or Java. So I want to use Vim editor, because it is very flexible. I have heard that I can configure the Vim editor to be able to go from object to the definition from function to the definition from class name to the definition Do we have any professional Vim-er that could tell me how exactly to configure Vim for that? Thanks in advance. P.S. In case readers will consider this question is not connected with programming, I would say that this is improving speed of programming. So it is a help to the programmer. So please don't close this question. EDIT: Also I would like to know how vim works with code completion and can vim hint the list of methods that are available for the certain object? If yes, then I would like to know how to configure these options too?

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  • LINQ2SQL: orderby note.hasChildren(), name ascending

    - by Peter Bridger
    I have a hierarchical data structure which I'm displaying in a webpage as a treeview. I want to data to be ordered to first show nodes ordered alphabetically which have no children, then under these nodes ordered alphabetically which have children. Currently I'm ordering all nodes in one group, which means nodes with children appear next to nodes with no children. I'm using a recursive method to build up the treeview, which has this LINQ code at it's heart: var filteredCategory = from c in category orderby c.Name ascending where c.ParentCategoryId == parentCategoryId && c.Active == true select c; So this is the orderby statement I want to enhance. Shown below is the database table structure: [dbo].[Category]( [CategoryId] [int] IDENTITY(1,1) NOT NULL, [Name] [varchar](100) NOT NULL, [Level] [tinyint] NOT NULL, [ParentCategoryId] [int] NOT NULL, [Selectable] [bit] NOT NULL CONSTRAINT [DF_Category_Selectable] DEFAULT ((1)), [Active] [bit] NOT NULL CONSTRAINT [DF_Category_Active] DEFAULT ((1))

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  • How to do a proper search with nhibernate

    - by Denis Rosca
    Hello everyone, i'm working on a small project that is supposed to allow basic searches of the database. Currently i'm using nhibernate for the database interaction. In the database i have 2 tables: Person and Address. The Person table has a many-to-one relationship with Address. The code i've come up with for doing searches is: public IList<T> GetByParameterList(List<QueryParameter> parameterList) { if (parameterList == null) { return GetAll(); } using (ISession session = NHibernateHelper.OpenSession()) { ICriteria criteria = session.CreateCriteria<T>(); foreach (QueryParameter param in parameterList) { switch (param.Constraint) { case ConstraintType.Less: criteria.Add(Expression.Lt(param.ParameterName, param.ParameterValue)); break; case ConstraintType.More: criteria.Add(Expression.Gt(param.ParameterName, param.ParameterValue)); break; case ConstraintType.LessOrEqual: criteria.Add(Expression.Le(param.ParameterName, param.ParameterValue)); break; case ConstraintType.EqualOrMore: criteria.Add(Expression.Ge(param.ParameterName, param.ParameterValue)); break; case ConstraintType.Equals: criteria.Add(Expression.Eq(param.ParameterName, param.ParameterValue)); break; case ConstraintType.Like: criteria.Add(Expression.Like(param.ParameterName, param.ParameterValue)); break; } } try { IList<T> result = criteria.List<T>(); return result; } catch { //TODO: Implement some exception handling throw; } } } The query parameter is a helper object that i use to create criterias and send it to the dal, it looks like this: public class QueryParameter { public QueryParameter(string ParameterName, Object ParameterValue, ConstraintType constraintType) { this.ParameterName = ParameterName; this.ParameterValue = ParameterValue; this.Constraint = constraintType; } public string ParameterName { get; set; } public Object ParameterValue { get; set; } public ConstraintType Constraint { get; set; } } Now this works well if i'm doing a search like FirstName = "John" , but not when i try to give a parameter like Street = "Some Street". It seems that nhibernate is looking for a street column in the Person table but not in the Address table. Any idea on how should i change my code for so i could do a proper search? Tips? Maybe some alternatives? Disclaimer: i'm kind of a noob so please be gentle ;) Thanks, Denis.

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  • Error creating a table : "There is already an object named ... in the database", but not object with

    - by DavRob60
    Hi, I'm trying to create a table on a Microsoft SQL Server 2005 (Express). When i run this query USE [QSWeb] GO /****** Object: Table [dbo].[QSW_RFQ_Log] Script Date: 03/26/2010 08:30:29 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO SET ANSI_PADDING ON GO CREATE TABLE [dbo].[QSW_RFQ_Log]( [RFQ_ID] [int] NOT NULL, [Action_Time] [datetime] NOT NULL, [Quote_ID] [int] NULL, [UserName] [nvarchar](256) NOT NULL, [Action] [int] NOT NULL, [Parameter] [int] NULL, [Note] [varchar](255) NULL, CONSTRAINT [QSW_RFQ_Log] PRIMARY KEY CLUSTERED ( [RFQ_ID] ASC, [Action_Time] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO I got this error message Msg 2714, Level 16, State 4, Line 2 There is already an object named 'QSW_RFQ_Log' in the database. Msg 1750, Level 16, State 0, Line 2 Could not create constraint. See previous errors. but if i try to find the object in question using this query: SELECT * FROM QSWEB.sys.all_objects WHERE upper(name) like upper('QSW_RFQ_%') I got this (0 row(s) affected) What is going on????

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  • How do I get started on a bigger project?

    - by Axilus
    Hey guys, Most of the time I have been programming little apps either for myself or for the benifit of learning. Now that my programming skills are considered somewhat intermediate, I was wondering how I would tackle a large programming project. Lets suppose I wanted to make an application that has a lot of features and is intended for the use of others and not just myself; how do I go about planning for such projects? Do I just jump in and start coding the thing or is there some sort of recommended process? Thanks in advance :D

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  • Web.xml: Are url-pattern tags relative to each other?

    - by sixtyfootersdude
    <servlet-mapping> <servlet-name>myName</servlet-name> <url-pattern>/aName</url-pattern> </servlet-mapping> <security-constraint> <web-resource-collection> ... <url-pattern> /* </url-pattern> </web-resource-collection> ... </security-constraint> This is an excerpt from web.xml (using it to configure a jboss/tomcat webservice). Just wondering if the url-pattern in web-resource-collection is relative to the url-pattern in servlet-mapping.

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  • "Zoom" text to be as big as possible within constraints/box

    - by stolsvik
    First problem: You have 400 pixels width to go on, and need to fit some text within that constraint as large as possible (thus, the text shall use that amount of space). Throw in a new constraint: If the text is just "A", then it shall not zoom this above 100 pixels (or some specific font size). Then, a final situation: Linebreaks. Fit some text in the largest possible way within e.g. 400 x 150 pixels. An obvious way is to simply start with point 1, and then increase until you can't fit it anymore. This would work for all three problems, but would be very crude. The fitting of a single line within bounds could be done by writing it with some fixed point size, check the resulting pixel bounds of the text, and then simply scale it with a transform (the text scales properly too then, check out TransformUI). Any ideas of other ways to attack this would be greatly appreciated!

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  • Win32: No Window Appears

    - by SoulBeaver
    I was programming the example code from Frank Luna's book "Introduction to 3D Game Programming with DirectX 10". The code is the first Win32 example in the Appendix A: Windows Programming section. Right now, the program compiles under both VC++ 2008/2010, but no window appears, although the debug session has started and I have to forcefully close it. I have no idea where it is, I'm not using Win32 Console mode, I have closed all other windows and no other IDE or session of VC++ is running. Any idea why this might be happening? PS: I have also checked my Processes. It is indeed running.

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  • Constrain a table to have only one row

    - by finnw
    What's the cleanest way to constrain a SQL table to allow it to have no more than one row? This related question discusses why such a table might exist, but not how the constraint should be implemented. So far I have only found hacks involving a unique key column that is constrained to have a specific value, e.g. ALWAYS_0 TINYINT NOT NULL PRIMARY KEY DEFAULT (0) CONSTRAINT CHECK_ALWAYS_0 CHECK (ALWAYS_0 = 0). I am guessing there is probably a cleaner way to do it. The ideal solution would be portable SQL, but a solution specific to MS SQL Server or postgres would also be useful

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  • Error: Too Many Arguments Specified when Inserting Values from ASP.NET to SQL Server

    - by SidC
    Good Afternoon All, I have a wizard control that contains 20 textboxes for part numbers and another 20 for quantities. I want the part numbers and quantities loaded into the following table: USE [Diel_inventory] GO /****** Object: Table [dbo].[QUOTEDETAILPARTS] Script Date: 05/09/2010 16:26:54 ******/ SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE TABLE [dbo].[QUOTEDETAILPARTS]( [QuoteDetailPartID] [int] IDENTITY(1,1) NOT NULL, [QuoteDetailID] [int] NOT NULL, [PartNumber] [float] NULL, [Quantity] [int] NULL, CONSTRAINT [pkQuoteDetailPartID] PRIMARY KEY CLUSTERED ( [QuoteDetailPartID] ASC )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO ALTER TABLE [dbo].[QUOTEDETAILPARTS] WITH CHECK ADD CONSTRAINT [fkQuoteDetailID] FOREIGN KEY([QuoteDetailID]) REFERENCES [dbo].[QUOTEDETAIL] ([ID]) ON UPDATE CASCADE ON DELETE CASCADE GO Here's the snippet from my sproc for this insert: set @ID=scope_identity() Insert into dbo.QuoteDetailParts (QuoteDetailPartID, QuoteDetailID, PartNumber, Quantity) values (@ID, @QuoteDetailPartID, @PartNumber, @Quantity) When I run the ASPX page, I receive an error that there are too many arguments specified for my stored procedure. I understand why I'm getting the error, given the above table layout. However, I need help in structuring my insert syntax to look for values in all 20 PartNumber and Quantity field pairs. Thanks, Sid

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  • How to 'insert if not exists' in MySQL?

    - by warren
    I started by googling, and found this article which talks about mutex tables. I have a table with ~14 million records. If I want to add more data in the same format, is there a way to ensure the record I want to insert does not already exist without using a pair of queries (ie, one query to check and one to insert is the result set is empty)? Does a unique constraint on a field guarantee the insert will fail if it's already there? It seems that with merely a constraint, when I issue the insert via php, the script croaks.

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  • SRAM Cell Diagram - Can someone explain this a bit more clearly? ( From COMP1917 @ UNSW: Lecture 2 o

    - by Kristina
    I've begun watching a series of first year lectures from the University of New South Wales (UNSW) in Australia, and I'm a bit perplexed by the instructors explanation of how an SRAM gate works. I realize this isn't exactly "programming-related" but since it comes from a series of lectures relating to computing and programming, I thought StackOverflow may be able to help (reddit failed me entirely). In this lecture beginning at around 32:12, Richard (the lecturer) tries to explain how a "latch gate" works within SRAM. Although his students seem to keep up, I feel I'm missing something crucial which is preventing the concept from really "clicking" in my brain. For convenience, I've added the image from the video below: Thanks in advance for any help you can provide, but if this question doesn't fit your view of "programming-related" could you please provide an alternate forum for this in a comment when you cast your close vote? Thanks!

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  • integrity Constraints on a table.

    - by Dinesh
    See this sample schema Passenger(id PK, Name) Plane(id PK, capacity, type); Flight(id PK, planeId FK(Plane), flightDate, StartLocation, destination) CREATE TABLE Reservation(PassengerId, flightId, PRIMARY KEY (passengerId, flightId), FOREIGN KEY (passengerId) REFERENCES Passenger, FOREIGN KEY (flightId) REFERENCES Flight); I need to define an integrity constraint that enforces the restriction that the number of passengers on a plane cannot exceed the plane’s capacity. I have tried and achieved so far is this. CREATE TABLE Reservation( passengerId INTEGER, flightId INTEGER, PRIMARY KEY (passengerId, flightId), FOREIGN KEY (passengerId) REFERENCES Passenger, FOREIGN KEY (flightId) REFERENCES Flight, Constraint check1 check(Not Exists(select * from Flight s, (select count(*) as totalRes from Reservation group by flightId) t where t.totalRes > s.capacity ) ) ); I am not sure i am doing in right way or not. Any suggestions?

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  • is it better to use a "natural" language to write code?

    - by M.H
    I recently saw a programming language called supernova and they said in the web page : The Supernova Programming language is a modern scripting language and the First one presents the concept of programming with direct Fiction Description using Clear subset of pure Human Language. and you can write code like: i want window and the window title is Hello World. i want button and button caption is Close. and button name is btn1. btn1 mouse click. instructions are you close window end of instructions my question is not about the language itself but it is that are we need such languages and did they make writing code easier or not?

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  • A good F# codebase to learn from

    - by Lucas
    Hi all, I've been teaching myself F# for a while now. I've read Programming F# by Chris Smith (great book) and I've written a few small scripts for getting the job done here and there. But IMO the best way to learn a new programming language—and more importantly, the idioms that come with it—is to read a good open source codebase written in that language. Naturally, writing code in that language is crucial, but in the beginning, you're basically struggling with your own ignorance about how things should be done. You could perform certain tasks one way or the other, but it takes experience to realize the flaws and virtues of each. Even after you've gotten a firm grasp of how things work, reading the code of people who have an even firmer one helps a great deal. Most would agree that the most insightful parts of any learn-a-programming-language book are the code examples, and reading a well-written open source codebase is the next level of that. So are there any out there for F#?

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  • Please Recommend CS Project books

    - by kunjaan
    Programming Collective Intelligence is an awesome way to get your feet wet in Machine learning. I am looking for similar books which has small but interesting programming projects. Do you have any recommendations? Edit: It need not be related to machine learning. It could be any programming project-based books. Thanks. Edit2: Collective Intelligence in Action is one more book that looks at some interesting CS stuffs. Do you guys have any similar recommendations?

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  • is it better to use a "natural" language to write codes ?

    - by M.H
    I recently saw a programming language called supernova and they said in the web page : The Supernova Programming language is a modern scripting language and the First one presents the concept of programming with direct Fiction Description using Clear subset of pure Human Language. and you can write codes like : i want window and the window title is Hello World. i want button and button caption is Close. and button name is btn1. btn1 mouse click. instructions are you close window end of instructions my question is not about the language itself but it is that are we need such languages and did they make writing codes more easier or not ?

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