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  • Does it exist: smart pointer, owned by one object allowing access.

    - by Noah Roberts
    I'm wondering if anyone's run across anything that exists which would fill this need. Object A contains an object B. It wants to provide access to that B to clients through a pointer (maybe there's the option it could be 0, or maybe the clients need to be copiable and yet hold references...whatever). Clients, lets call them object C, would normally, if we're perfect developers, be written carefully so as to not violate the lifetime semantics of any pointer to B they might have...but we're not perfect, in fact we're pretty dumb half the time. So what we want is for object C to have a pointer to object B that is not "shared" ownership but that is smart enough to recognize a situation in which the pointer is no longer valid, such as when object A is destroyed or it destroys object B. Accessing this pointer when it's no longer valid would cause an assertion/exception/whatever. In other words, I wish to share access to data in a safe, clear way but retain the original ownership semantics. Currently, because I've not been able to find any shared pointer in which one of the objects owns it, I've been using shared_ptr in place of having such a thing. But I want clear owneship and shared/weak pointer doesn't really provide that. Would be nice further if this smart pointer could be attached to member variables and not just hold pointers to dynamically allocated memory regions. If it doesn't exist I'm going to make it, so I first want to know if someone's already released something out there that does it. And, BTW, I do realize that things like references and pointers do provide this sort of thing...I'm looking for something smarter.

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  • Nhibernate, can i improve my MAPPING or Query

    - by dbones
    take this simple example A staff class which references other instances of the staff class public class Staff { public Staff() { Team = new List<Staff>(); } public virtual int Id { get; set; } public virtual string Name { get; set; } public virtual IList<Staff> Team { get; set; } public virtual Staff Manager { get; set; } } The Fluent Mapping public class StaffMap : ClassMap<Staff> { public StaffMap() { Id(x => x.Id); Map(x => x.Name); References(x => x.Manager).Column("ManagerId"); HasMany(x => x.Team).KeyColumn("ManagerId").Inverse(); } } Now I want to run a query, which will load all the Staff and eager load the manager and Team members. This is what I came up with IList<Staff> resutls = session.CreateCriteria<Staff>() .SetFetchMode("Team", FetchMode.Eager) .SetResultTransformer(Transformers.DistinctRootEntity) .List<Staff>(); however the SQL (does what i want) has duplicate columns, 2 team2_.ManagerId and 2 team2_.Id SELECT this_.Id as Id0_1_, this_.Name as Name0_1_, this_.ManagerId as ManagerId0_1_, team2_.ManagerId as ManagerId3_, team2_.Id as Id3_, team2_.Id as Id0_0_, team2_.Name as Name0_0_, team2_.ManagerId as ManagerId0_0_ FROM [SelfRef].[dbo].[Staff] this_ left outer join [SelfRef].[dbo].[Staff] team2_ on this_.Id=team2_.ManagerId The question is, should this be happening? did i do something wrong in the query or map? or is it a feature of the HHib im using (which is Version 2.1.0.4000)? many thanks in advance

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  • Compile for mixed platform (32, 64) and reference a 32 or 64 bit DLL resolved at runtime

    - by Nigel Aston
    Using VS2010 under windows 32 or 64 bit. Our C# app calls a 3rd party DLL (managed) that interfaces to an unmanaged DLL. The 3rd party DLL API appears identical in 32 or 64 bit although underneath it links to a 32 or 64 bit unmanaged DLL. We want our C# app to run on either 32 or 64 bit OS, ideally it will auto detect the OS and load the appropriate 32rd party DLL - via a simple factory class which tests the Enviroment. So the neatest solution would be a runtime folder containing: OurApp.exe 3rdParty32.DLL 3rdPartyUnmanaged32.DLL 3rdParty64.DLL 3rdPartyUnmanaged64.DLL However, the interface for the managed 3rdParty 32 and 64 dll is identical so both cannot be referenced within the same VS2010 project: when adding the second the warning triangle is shown and it does not get referenced. Is my only answer to create two extra library DLL projects to reference the 3rdParty 32 and 64 Dlls? So I would end up with this project arrangement: Project 1: Builds OurApp.exe, dynamically creates an object for project2 or project3. Project 2: Builds OurApp32.DLL which references 3rdParty32.dll Project 3: Builds OurApp64.DLL which references 3rdParty64.dll

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  • PowerPoint PlugIn does not read defaults from .dll.config file

    - by Nick T
    I'm working on a very simple PowerPoint plugin, and I'm quite a bit stumped. In my settings.settings file, I have configured a setting "StartPath", which references where the PowerPoint plugin will navigate to using a Browser component. After I compile the application, and run the installer generated by the Setup project, the application is installed and uses the default value in the settings file. However, if I edit the application.dll.config file, the plugin still uses the old values. How can I set things up such that the plugin references the .dll.config file and not its default settings? The code to access the settings is listed below, including the other variants I have tried: //Attempt 1 string location = MyApplication.Properties.Settings.Default.StartPath; //Attempt 2 string location = ConfigurationManager.AppSettings["StartPath"]; //Attempt 3: Configuration element is inaccessible due to its protection level string applicationName = Environment.GetCommandLineArgs()[0] + ".exe"; string exePath = System.IO.Path.Combine(Environment.CurrentDirectory, applicationName); Configuration config = ConfigurationManager.OpenExeConfiguration(exePath); string location = config.AppSettings["StartPath"];

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  • Symfony generating database from model

    - by Sergej Jevsejev
    Hello, I am having troubles generating a simple database form model. I am using: Doctrine on Symfony 1.4.4 MySQL Workbench 5.2.16 with Doctrine Export 0.4.2dev So my ERL Model is: http://img708.imageshack.us/img708/1716/tmg.png Genereted YAML file: --- detect_relations: true options: collate: utf8_unicode_ci charset: utf8 type: InnoDB Course: columns: id: type: integer(4) primary: true notnull: true autoincrement: true name: type: string(255) notnull: true keywords: type: string(255) notnull: true summary: type: clob(65535) notnull: true Lecture: columns: id: type: integer(4) primary: true notnull: true autoincrement: true course_id: type: integer(4) primary: true notnull: true name: type: string(255) notnull: true description: type: string(255) notnull: true url: type: string(255) relations: Course: class: Course local: course_id foreign: id foreignAlias: Lectures foreignType: many owningSide: true User: columns: id: type: integer(4) primary: true unique: true notnull: true autoincrement: true firstName: type: string(255) notnull: true lastName: type: string(255) notnull: true email: type: string(255) unique: true notnull: true designation: type: string(1024) personalHeadline: type: string(1024) shortBio: type: clob(65535) UserCourse: tableName: user_has_course columns: user_id: type: integer(4) primary: true notnull: true course_id: type: integer(4) primary: true notnull: true relations: User: class: User local: user_id foreign: id foreignAlias: UserCourses foreignType: many owningSide: true Course: class: Course local: course_id foreign: id foreignAlias: UserCourses foreignType: many owningSide: true And no matter what I try this error occurs after: symfony doctrine:build --all --no-confirmation SQLSTATE[42000]: Syntax error or access violation: 1072 Key column 'user_userid' doesn't exist in table. Failing Query: "ALTER TABLE user_has_course ADD CONSTRAINT user_has_course_user_userid_user_id FOREIGN KEY (user_userid) REFERENCES user(id)". Failing Query: ALTER TABLE user_has_course ADD CONSTRAINT user_has_cou rse_user_userid_user_id FOREIGN KEY (user_userid) REFERENCES user(id) Currently I am studying Symfony, and stuck with this error. Please help.

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  • Returning a reference from a Class member?

    - by nebukadnezzar
    Hi, I've a class that basically looks like this: class App { public function newTemplate($filename, $vars=array()) { $smarty = new Smarty; $smarty->compile_dir = $this->template_compile_path; if(count($vars) > 0) { foreach($vars as $v_key => $v_name) { $smarty->assign($v_key, $v_name); } } return $smarty; } } However, when I create a Instance of 'App', the reference to $smarty seems broken, as every call to the membermethods don't seem to do anything: $app = new App; $tpl = $app->newTemplate("index.tmpl"); $tpl->assign("foo", "bar"); // {$foo} does not appear with "bar" in the template Now I wonder why? Of course I tried to use references: ... public function &newTemplate() ... ... But that doesn't work. Variable references don't seem to work either: ... $tpl = &$app->newTemplate("index.tmpl"); ... What is causing PHP here not to return a proper reference? Help is very appreciated!

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  • Loop to check all 14 days in the pay period

    - by Rachel Ann Arndt
    Name: Calc_Anniversary Input: Pay_Date, Hire_Date, Termination_Date Output: "Y" if is the anniversary of the employee's Hire_Date, "N" if it is not, and "T" if he has been terminated before his anniversary. Description: Create local variables to hold the month and day of the employee's Date_of_Hire, Termination_Date, and of the processing date using the TO_CHAR function. First check to see if he was terminated before his anniversary. The anniversary could be on any day during the pay period, so there will be a loop to check all 14 days in the pay period to see if one was his anniversary. CREATE OR replace FUNCTION Calc_anniversary( incoming_anniversary_date IN VARCHAR2) RETURN BOOLEAN IS hiredate VARCHAR2(20); terminationdate VARCHAR(20); employeeid VARCHAR2(38); paydate NUMBER := 0; BEGIN SELECT Count(arndt_raw_time_sheet_data.pay_date) INTO paydate FROM arndt_raw_time_sheet_data WHERE paydate = incoming_anniversary_date; WHILE paydate <= 14 LOOP SELECT To_char(employee_id, '999'), To_char(hire_date, 'DD-MON'), To_char(termination_date, 'DD-MON') INTO employeeid, hiredate, terminationdate FROM employees, time_sheet WHERE employees.employee_id = time_sheet.employee_id AND paydate = pay_date; IF terminationdate > hiredate THEN RETURN 'T'; ELSE IF To_char(SYSDATE, 'DD-MON') = To_char(hiredate, 'DD-MON')THEN RETURN 'Y'; ELSE RETURN 'N'; END IF; END IF; paydate := paydate + 1; END LOOP; END; Tables I am using CREATE TABLE Employees ( EMPLOYEE_ID INTEGER, FIRST_NAME VARCHAR2(15), LAST_NAME VARCHAR2(25), ADDRESS_LINE_ONE VARCHAR2(35), ADDRESS_LINE_TWO VARCHAR2(35), CITY VARCHAR2(28), STATE CHAR(2), ZIP_CODE CHAR(10), COUNTY VARCHAR2(10), EMAIL VARCHAR2(16), PHONE_NUMBER VARCHAR2(12), SOCIAL_SECURITY_NUMBER VARCHAR2(11), HIRE_DATE DATE, TERMINATION_DATE DATE, DATE_OF_BIRTH DATE, SPOUSE_ID INTEGER, MARITAL_STATUS CHAR(1), ALLOWANCES INTEGER, PERSONAL_TIME_OFF FLOAT, CONSTRAINT pk_employee_id PRIMARY KEY (EMPLOYEE_ID), CONSTRAINT fk_spouse_id FOREIGN KEY (SPOUSE_ID) REFERENCES EMPLOYEES (EMPLOYEE_ID)) / CREATE TABLE Arndt_Raw_Time_Sheet_data ( EMPLOYEE_ID INTEGER, PAY_DATE DATE, HOURS_WORKED FLOAT, SALES_AMOUNT FLOAT, CONSTRAINT pk_employee_id_pay_date_time PRIMARY KEY (EMPLOYEE_ID, PAY_DATE), CONSTRAINT fk_employee_id_time FOREIGN KEY (EMPLOYEE_ID) REFERENCES EMPLOYEES (EMployee_ID)); error FUNCTION Calc_Anniversary compiled Warning: execution completed with warning

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  • How do I enforce the order of qmake library dependencies?

    - by James Oltmans
    I'm getting a lot of errors because qmake is improperly ordering the boost libraries I'm using. Here's what .pro file looks like QT += core gui TARGET = MyTarget TEMPLATE = app CONFIG += no_keywords \ link_pkgconfig SOURCES += file1.cpp \ file2.cpp \ file3.cpp PKGCONFIG += my_package \ sqlite3 LIBS += -lsqlite3 \ -lboost_signals \ -lboost_date_time HEADERS += file1.h\ file2.h\ file3.h FORMS += mainwindow.ui RESOURCES += Resources/resources.qrc This produces the following command: g++ -Wl,-O1 -o MyTarget file1.o file2.o file3.o moc_mainwindow.o -L/usr/lib/x86_64-linux-gnu -lboost_signals -lboost_date_time -L/usr/local/lib -lmylib1 -lmylib2 -lsqlite3 -lQtGui -lQtCore Note: mylib1 and mylib2 are statically compiled by another project, placed in /usr/local/lib with an appropriate pkg-config .pc file pointing there. The .pro file references them via my_package in PKGCONFIG. The problem is not with pkg-config's output but with Qt's ordering. Here's the .pc file: prefix=/usr/local exec_prefix=${prefix} libdir=${exec_prefix}/lib includedir=${prefix}/include Name: my_package Description: My component package Version: 0.1 URL: http://example.com Libs: -L${libdir} -lmylib1 -lmylib2 Cflags: -I${includedir}/my_package/ The linking stage fails spectacularly as mylib1 and mylib2 come up with a lot of undefined references to boost libraries that both the app and mylib1 and mylib2 are using. We have another build method using scons and it properly orders things for the linker. It's build command order is below. g++ -o MyTarget file1.o file2.o file3.o moc_mainwindow.o -L/usr/local/lib -lmylib1 -lmylib2 -lsqlite3 -lboost_signals -lboost_date_time -lQtGui -lQtCore Note that the principle difference is the order of the boost libs. Scons puts them at the end just before QtGui and QtCore while qmake puts them first. The other differences in the compile commands are unimportant as I have hand modified the qmake produced make file and the simple reordering fixed the problem. So my question is, how do I enforce the right order in my .pro file despite what qmake thinks they should be?

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  • Dealing with Expression Blend's lack of support for C++/CLI projects

    - by Brian Ensink
    I have a WPF C# project that references a C++/CLI mixed mode project. I'm having trouble using the WPF project in Expression Blend 3. I'm new to Blend so perhaps this is obvious, but it won't display the xaml designer properly until it builds the project. In my case it complains that my custom commands are not "recognized or accessible" and the solution is to build the project in Blend. But I can't build the project because it references a C++/CLI mixed mode project which Blend won't load. The WPF project is pure C# it just happens to reference a C++/CLI mixed mode project but I'm not asking Blend to do anything with the mixed-mode assembly. How can I work around this problem? Edit: I was able to get it to build by removing the reference to the C++/CLI mixed mode project and replacing it with a reference to the actual assembly. However this is not ideal because in my past experience Visual Studio will not always be able to resolve the reference when switching between release and debug configurations.

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  • Avoiding duplicate objects in Java deserialization

    - by YGL
    I have two lists (list1 and list2) containing references to some objects, where some of the list entries may point to the same object. Then, for various reasons, I am serializing these lists to two separate files. Finally, when I deserialize the lists, I would like to ensure that I am not re-creating more objects than needed. In other words, it should still be possible for some entry of List1 to point to the same object as some entry in List2. MyObject obj = new MyObject(); List<MyObject> list1 = new ArrayList<MyObject>(); List<MyObject> list2 = new ArrayList<MyObject>(); list1.add(obj); list2.add(obj); // serialize to file1.ser ObjectOutputStream oos = new ObjectOutputStream(...); oos.writeObject(list1); oos.close(); // serialize to file2.ser oos = new ObjectOutputStream(...); oos.writeObject(list2); oos.close(); I think that sections 3.4 and A.2 of the spec say that deserialization strictly results in the creation of new objects, but I'm not sure. If so, some possible solutions might involve: Implementing equals() and hashCode() and checking references manually. Creating a "container class" to hold everything and then serializing the container class. Is there an easy way to ensure that objects are not duplicated upon deserialization? Thanks.

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  • How much does an InnoDB table benefit from having fixed-length rows?

    - by Philip Eve
    I know that dependent on the database storage engine in use, a performance benefit can be found if all of the rows in the table can be guaranteed to be the same length (by avoiding nullable columns and not using any VARCHAR, TEXT or BLOB columns). I'm not clear on how far this applies to InnoDB, with its funny table arrangements. Let's give an example: I have the following table CREATE TABLE `PlayerGameRcd` ( `User` SMALLINT UNSIGNED NOT NULL, `Game` MEDIUMINT UNSIGNED NOT NULL, `GameResult` ENUM('Quit', 'Kicked by Vote', 'Kicked by Admin', 'Kicked by System', 'Finished 5th', 'Finished 4th', 'Finished 3rd', 'Finished 2nd', 'Finished 1st', 'Game Aborted', 'Playing', 'Hide' ) NOT NULL DEFAULT 'Playing', `Inherited` TINYINT NOT NULL, `GameCounts` TINYINT NOT NULL, `Colour` TINYINT UNSIGNED NOT NULL, `Score` SMALLINT UNSIGNED NOT NULL DEFAULT 0, `NumLongTurns` TINYINT UNSIGNED NOT NULL DEFAULT 0, `Notes` MEDIUMTEXT, `CurrentOccupant` TINYINT UNSIGNED NOT NULL DEFAULT 0, PRIMARY KEY (`Game`, `User`), UNIQUE KEY `PGR_multi_uk` (`Game`, `CurrentOccupant`, `Colour`), INDEX `Stats_ind_PGR` (`GameCounts`, `GameResult`, `Score`, `User`), INDEX `GameList_ind_PGR` (`User`, `CurrentOccupant`, `Game`, `Colour`), CONSTRAINT `Constr_PlayerGameRcd_User_fk` FOREIGN KEY `User_fk` (`User`) REFERENCES `User` (`UserID`) ON DELETE CASCADE ON UPDATE CASCADE, CONSTRAINT `Constr_PlayerGameRcd_Game_fk` FOREIGN KEY `Game_fk` (`Game`) REFERENCES `Game` (`GameID`) ON DELETE CASCADE ON UPDATE CASCADE ) ENGINE=INNODB CHARACTER SET utf8 COLLATE utf8_general_ci The only column that is nullable is Notes, which is MEDIUMTEXT. This table presently has 33097 rows (which I appreciate is small as yet). Of these rows, only 61 have values in Notes. How much of an improvement might I see from, say, adding a new table to store the Notes column in and performing LEFT JOINs when necessary?

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  • If a table has two xml columns, will inserting records be a lot slower?

    - by Lieven Cardoen
    Is it a bad thing to have two xml columns in one table? + How much slower are these xml columns in terms of updating/inserting/reading data? In profiler this kind of insert normally takes 0 ms, but sometimes it goes up to 160ms: declare @p8 xml set @p8=convert(xml,N'<interactions><interaction correct="false" score="0" id="0" gapid="0" x="61" y="225"><feedback/><element id="0" position="0" elementtype="1"><asset/></element></interaction><interaction correct="false" score="0" id="1" gapid="1" x="64" y="250"><feedback/><element id="0" position="0" elementtype="1"><asset/></element></interaction><interaction correct="false" score="0" id="2" gapid="2" x="131" y="250"><feedback/><element id="0" position="0" elementtype="1"><asset/></element></interaction></interactions>') declare @p14 xml set @p14=convert(xml,N'<contentinteractions/>') exec sp_executesql N'INSERT INTO [dbo].[PackageSessionNodes]([dbo].[PackageSessionNodes].[PackageSessionId], [dbo].[PackageSessionNodes].[TreeNodeId],[dbo].[PackageSessionNodes].[Duration], [dbo].[PackageSessionNodes].[Score],[dbo].[PackageSessionNodes].[ScoreMax], [dbo].[PackageSessionNodes].[Interactions],[dbo].[PackageSessionNodes].[BrainTeaser], [dbo].[PackageSessionNodes].[DateCreated], [dbo].[PackageSessionNodes].[CompletionStatus], [dbo].[PackageSessionNodes].[ReducedScore], [dbo].[PackageSessionNodes].[ReducedScoreMax], [dbo].[PackageSessionNodes].[ContentInteractions]) VALUES (@ins_dboPackageSessionNodesPackageSessionId, @ins_dboPackageSessionNodesTreeNodeId, @ins_dboPackageSessionNodesDuration, @ins_dboPackageSessionNodesScore, @ins_dboPackageSessionNodesScoreMax, @ins_dboPackageSessionNodesInteractions, @ins_dboPackageSessionNodesBrainTeaser, @ins_dboPackageSessionNodesDateCreated, @ins_dboPackageSessionNodesCompletionStatus, @ins_dboPackageSessionNodesReducedScore, @ins_dboPackageSessionNodesReducedScoreMax, @ins_dboPackageSessionNodesContentInteractions) ; SELECT SCOPE_IDENTITY() as new_id This is the table: CREATE TABLE [dbo].[PackageSessionNodes]( [PackageSessionNodeId] [int] IDENTITY(1,1) NOT NULL, [PackageSessionId] [int] NOT NULL, [TreeNodeId] [int] NOT NULL, [Duration] [int] NULL, [Score] [float] NOT NULL, [ScoreMax] [float] NOT NULL, [Interactions] [xml] NOT NULL, [BrainTeaser] [bit] NOT NULL, [DateCreated] [datetime] NULL, [CompletionStatus] [int] NOT NULL, [ReducedScore] [float] NOT NULL, [ReducedScoreMax] [float] NOT NULL, [ContentInteractions] [xml] NOT NULL, CONSTRAINT [PK_PackageSessionNodes] PRIMARY KEY CLUSTERED ( [PackageSessionNodeId] 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].[PackageSessionNodes] WITH CHECK ADD CONSTRAINT [FK_PackageSessionNodes_PackageSessions] FOREIGN KEY([PackageSessionId]) REFERENCES [dbo].[PackageSessions] ([PackageSessionId]) ON UPDATE CASCADE ON DELETE CASCADE GO ALTER TABLE [dbo].[PackageSessionNodes] CHECK CONSTRAINT [FK_PackageSessionNodes_PackageSessions] GO ALTER TABLE [dbo].[PackageSessionNodes] WITH CHECK ADD CONSTRAINT [FK_PackageSessionNodes_TreeNodes] FOREIGN KEY([TreeNodeId]) REFERENCES [dbo].[TreeNodes] ([TreeNodeId]) GO ALTER TABLE [dbo].[PackageSessionNodes] CHECK CONSTRAINT [FK_PackageSessionNodes_TreeNodes] GO ALTER TABLE [dbo].[PackageSessionNodes] ADD CONSTRAINT [DF_PackageSessionNodes_Score] DEFAULT ((-1)) FOR [Score] GO ALTER TABLE [dbo].[PackageSessionNodes] ADD CONSTRAINT [DF_PackageSessionNodes_ScoreMax] DEFAULT ((-1)) FOR [ScoreMax] GO ALTER TABLE [dbo].[PackageSessionNodes] ADD CONSTRAINT [DF_PackageSessionNodes_DateCreated] DEFAULT (getdate()) FOR [DateCreated] GO ALTER TABLE [dbo].[PackageSessionNodes] ADD CONSTRAINT [DF_PackageSessionNodes_ReducedScore] DEFAULT ((-1)) FOR [ReducedScore] GO ALTER TABLE [dbo].[PackageSessionNodes] ADD CONSTRAINT [DF_PackageSessionNodes_ReducedScoreMax] DEFAULT ((-1)) FOR [ReducedScoreMax] GO

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  • Multiple Solution Layout for ASP.NET Web Portal?

    - by Jared S
    At work, we've developed a custom ASP.NET Web Portal (That's very similar to iGoogle). We have "Apps" (self-contained, large web forms) and "Modules" (similar to Google Gadgets). Currently, we use a single-solution model. Right now, we have: 3 core projects 60 application projects 80 module projects To reduce copy and pasting between projects, we're going to factor out common functionality (Data Access, Business Logic) into separate projects. I'd also like to introduce Unit Tests, which is going to increase the number of projects even more. We've already reached the point where Visual Studio is choking on the number of projects. We generally only load the 3 core projects and then whatever app's/module's project we're working on. Would a different solution structure help us out? Our number of projects is only going to increase. In general, an app or module only references the 3 core projects. Soon, apps/modules may start referencing the Data Access/Business Logic projects. But in general, apps and modules do not make references between themselves. So to recap, what is the best practice for solution structure when there are MANY projects that use a small number of core projects?

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  • Mixing has_one and has_and_belongs_to_many associations

    - by Thomas
    I'm trying to build a database of urls(links). I have a Category model that has and belongs to many Links. Here's the migration I ran: class CreateLinksCategories < ActiveRecord::Migration def self.up create_table :links_categories, :id => false do |t| t.references :link t.references :category end end def self.down drop_table :links_categories end end Here's the Link model: class Link < ActiveRecord::Base validates :path, :presence => true, :format => { :with => /^(#{URI::regexp(%w(http https))})$|^$/ } validates :name, :presence => true has_one :category end Here's the category model: class Category < ActiveRecord::Base has_and_belongs_to_many :links end And here's the error the console kicked back when I tried to associate the first link with the first category: >>link = Link.first => #<Link id: 1, path: "http://www.yahoo.com", created_at: "2011-01-10... >>category = Category.first => #<category id : 1, name: "News Site", created_at: "2011-01-11... >>link.category << category => ActiveRecord::StatementInvalid: SQLite3::Exception: no such column : categories.link_id: Are my associations wrong or am I missing something in the database? I expected it to find the links_categories table. Any help is appreciated.

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  • looking for advise on importing excel into mysql with php

    - by Ole Media
    Alright, see if I can pick your brains from you all. I'm currently working on a project where all the information comes from different clients, the only thing in common is that the received data is done with excel. The excel spread sheet that they present is just a bunch of references and codes, and the problem than I'm facing is that I need the references and codes to be entered in certain format in order for the website to work. The perfect situation will be to go to each client and teach how I would need the data, but I can't do that because of the large number of clients, and more importantly I will be interrupting their work flow. Each client has its own codes and reference model and they are not willing to change their process The good news is that there is a standard pattern for the codes, but I'm talking close to 200 thousand codes with a bunch of combination. They way that we are currently solving the problem is that we have a person who checks each excel sheet received, runs a few macros, and manually fixes those codes in which the macro was not able to fix. The person that is doing this, is already burn out and frustrated and I would like to automatize this process with php. Suggestions?

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  • Android Unit Testing - Resolution & Verification Problems

    - by Bill
    I just switched the way my Android project is being built and non of my unit tests work any more...I get errors like WARN/dalvikvm(575): VFY: unable to resolve static field X in ..... WARN/dalvikvm(575): VFY: unable to find class referenced in signature These errors only come from my Unit Tests, where classes defined in it can't even see other classes defined in the unit test. Before each project had its own directory with copies of the 3rd party jar files. I've read around that Dex does weird things with references but haven't been able to figure out how to fix this problem. Is there a better way to do this? I would love to see an example of a large Android workspace where there are multiple projects, jar references, etc... Is it possible to fix this with an Order/Export tweak ? The project is structured like this: Eclipse Workspace (PROJECT_HOME classpath variable) lib 3rd-party jars android.jar Java Project A Looks in PROJECT_HOME Java Project B Looks in PROJECT_HOME Depends on project A Android Project Depends on A & B Looks in PROJECT_HOME Android Test Project Depends on A , B, Android Project Looks in PROJECT_HOME

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  • Statically checking a Java app for link errors

    - by monorailkitty
    I have a scenario where I have code written against version 1 of a library but I want to ship version 2 of the library instead. The code has shipped and is therefore not changeable. I'm concerned that it might try to access classes or members of the library that existed in v1 but have been removed in v2. I figured it would be possible to write a tool to do a simple check to see if the code will link against the newer version of the library. I appreciate that the code may still be very broken even if the code links. I am thinking about this from the other side - if the code won't link then I can be sure there is a problem. As far as I can see, I need to run through the bytecode checking for references, method calls and field accesses to library classes then use reflection to check whether the class/member exists. I have three-fold question: (1) Does such a tool exist already? (2) I have a niggling feeling it is much more complicated that I imagine and that I have missed something major - is that the case? (3) Do you know of a handy library that would allow me to inspect the bytecode such that I can find the method calls, references etc.? Thanks!

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  • Does this copy the reference or the object?

    - by Water Cooler v2
    Sorry, I am being both thick and lazy, but mostly lazy. Actually, not even that. I am trying to save time so I can do more in less time as there's a lot to be done. Does this copy the reference or the actual object data? public class Foo { private NameValueCollection _nvc = null; public Foo( NameValueCollection nvc) { _nvc = nvc; } } public class Bar { public static void Main() { NameValueCollection toPass = new NameValueCollection(); new Foo( toPass ); // I believe this only copies the reference // so if I ever wanted to compare toPass and // Foo._nvc (assuming I got hold of the private // field using reflection), I would only have to // compare the references and wouldn't have to compare // each string (deep copy compare), right? } I think I know the answer for sure: it only copies the reference. But I am not even sure why I am asking this. I guess my only concern is, if, after instantiating Foo by calling its parameterized ctor with toPass, if I needed to make sure that the NVC I passed as toPass and the NVC private field _nvc had the exact same content, I would just need to compare their references, right?

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  • Dynamic Select boxes page load

    - by Chris
    Hello, I have a dynamic chained select box that I am attempting to show the value of on a page load. In my chained select box, it will default to the first option within the select box on page load, could anyone provide assitance? I stumbled upon this thread, but I can't seem to translate what they are doing with that answer to my language of CF. Dynamic chained drop downs on page refresh Here is the JS script I am using. function dynamicSelect(id1, id2) { // Feature test to see if there is enough W3C DOM support if (document.getElementById && document.getElementsByTagName) { // Obtain references to both select boxes var sel1 = document.getElementById(id1); var sel2 = document.getElementById(id2); // Clone the dynamic select box var clone = sel2.cloneNode(true); // Obtain references to all cloned options var clonedOptions = clone.getElementsByTagName("option"); // Onload init: call a generic function to display the related options in the dynamic select box refreshDynamicSelectOptions(sel1, sel2, clonedOptions); // Onchange of the main select box: call a generic function to display the related options in the dynamic select box sel1.onchange = function() { refreshDynamicSelectOptions(sel1, sel2, clonedOptions); } } } function refreshDynamicSelectOptions(sel1, sel2, clonedOptions) { // Delete all options of the dynamic select box while (sel2.options.length) { sel2.remove(0); } // Create regular expression objects for "select" and the value of the selected option of the main select box as class names var pattern1 = /( |^)(select)( |$)/; var pattern2 = new RegExp("( |^)(" + sel1.options[sel1.selectedIndex].value + ")( |$)"); // Iterate through all cloned options for (var i = 0; i < clonedOptions.length; i++) { // If the classname of a cloned option either equals "select" or equals the value of the selected option of the main select box if (clonedOptions[i].className.match(pattern1) || clonedOptions[i].className.match(pattern2)) { // Clone the option from the hidden option pool and append it to the dynamic select box sel2.appendChild(clonedOptions[i].cloneNode(true)); } } } Thanks so much for any assistance

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  • Creating a procedure with PLSQL

    - by user1857460
    I am trying to write a PLSQL function that implements a constraint that an employee cannot be both a driver and a mechanic at the same time, in other words, the same E# from TRKEMPLOYEE cannot be in TRKDRIVER and TRKMECHANIC at the same time. The abovementioned tables are something like as follows: TRKEMPLOYEE(E# NUMBER(12) NOT NULL CONSTRAINT TRKEMPLOYEE_PKEY PRIMARY KEY(E#)) TRKDRIVER(E# NUMBER(12) NOT NULL CONSTRAINT TRKDRIVER_PKEY PRIMARY KEY(E#), CONSTRAINT TRKDRIVER_FKEY FOREIGN KEY(E#) REFERENCES TRKEMPLOYEE(E#)) TRKMECHANIC(E# NUMBER(12) NOT NULL CONSTRAINT TRKMECHANIC_PKEY PRIMARY KEY(E#), CONSTRAINT TRKMECHANIC_FKEY FOREIGN KEY(E#) REFERENCES TRKEMPLOYEE(E#)) I have attempted to write a function but keep getting a compile error in line 1 column 7. Can someone tell me why my code doesn't work? My code is as follows CREATE OR REPLACE FUNCTION Verify() IS DECLARE E# TRKEMPLOYEE.E#%TYPE; CURSOR C1 IS SELECT E# FROM TRKEMPLOYEE; BEGIN OPEN C1; LOOP FETCH C1 INTO EMPNUM; IF(EMPNUM IN(SELECT E# FROM TRKMECHANIC )AND EMPNUM IN(SELECT E# FROM TRKDRIVER)) SELECT E#, NAME FROM TRKEMPLOYEE WHERE E#=EMPNUM; ELSE dbms_output.put_line(“OK”); ENDIF EXIT WHEN C1%NOTFOUND; END LOOP; CLOSE C1; END; / Any help would be appreciated. Thanks.

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  • Why would one want to use the public constructors on Boolean and similar immutable classes?

    - by Robert J. Walker
    (For the purposes of this question, let us assume that one is intentionally not using auto(un)boxing, either because one is writing pre-Java 1.5 code, or because one feels that autounboxing makes it too easy to create NullPointerExceptions.) Take Boolean, for example. The documentation for the Boolean(boolean) constructor says: Note: It is rarely appropriate to use this constructor. Unless a new instance is required, the static factory valueOf(boolean) is generally a better choice. It is likely to yield significantly better space and time performance. My question is, why would you ever want to get a new instance in the first place? It seems like things would be simpler if constructors like that were private. For example, if they were, you could write this with no danger (even if myBoolean were null): if (myBoolean == Boolean.TRUE) It'd be safe because all true Booleans would be references to Boolean.TRUE and all false Booleans would be references to Boolean.FALSE. But because the constructors are public, someone may have used them, which means that you have to write this instead: if (Boolean.TRUE.equals(myBoolean)) But where it really gets bad is when you want to check two Booleans for equality. Something like this: if (myBooleanA == myBooleanB) ...becomes this: if ( (myBooleanA == null && myBooleanB == null) || (myBooleanA == null && myBooleanA.equals(myBooleanB)) ) I can't think of any reason to have separate instances of these objects which is more compelling than not having to do the nonsense above. What say you?

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  • What rules govern cross-version compatibility for .NET applications and the C# language?

    - by John Feminella
    For some reason I've always had trouble remembering the backwards/forwards compatibility guarantees made by the framework, so I'd like to put that to bed forever. Suppose I have two assemblies, A and B. A is older and references .NET 2.0 assemblies; B references .NET 3.5 assemblies. I have the source for A and B, Ax and Bx, respectively; they are written in C# at the 2.0 and 3.0 language levels. (That is, Ax uses no features that were introduced later than C# 2.0; likewise Bx uses no features that were introduced later than 3.0.) I have two environments, C and D. C has the .NET 2.0 framework installed; D has the .NET 3.5 framework installed. Now, which of the following can/can't I do? Running: run A on C? run A on D? run B on C? run C on D? Compiling: compile Ax on C? compile Ax on D? compile Bx on C? compile Bx on D? Rewriting: rewrite Ax to use features from the C# 3 language level, and compile it on D, while having it still work on C? rewrite Bx to use features from the C# 4 language level on another environment E that has .NET 4, while having it still work on D?' Referencing from another assembly: reference B from A and have a client app on C use it? reference B from A and have a client app on D use it? reference A from B and have a client app on C use it? reference A from B and have a client app on D use it? More importantly, what rules govern the truth or falsity of these hypothetical scenarios?

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  • LNK1104: cannot open file 'kernel32.lib'

    - by Geoff
    I Had VS2010 installed but found that intellisense wasn't working. I looked on the web and found that I wasn't the only one who had that issue. So, I installed VS2008 and everything was fine. Then I decided to clean up my computer and removed VS2010 and immediately started getting this error on my programs (new and old). Even a simple test program that has one cout command. I tried repairing VS2008 and that didn't work so I tried to uninstall and then reinstall and still I am getting the same problem. I have looked online for this issue and though I have found a lot of other people are experiencing this issue it is not the same. They are having problems with other external references, not the ones that should automatically be included like kernel32 and lib32 etc. I also tried the solution that worked for some people with their other references and I included the path (with and without quotes) to my kernel32 directory but still I get the same problem, or in some instances I will get LNK1104: cannot open file 'C:\WINDOWS\system32.obj' with and without quotes in the linker config. Can anyone please help?

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  • MySQL: optimization of table (indexing, foreign key) with no primary keys

    - by Haradzieniec
    Each member has 0 or more orders. Each order contains at least 1 item. memberid - varchar, not integer - that's OK (please do not mention that's not very good, I can't change it). So, thera 3 tables: members, orders and order_items. Orders and order_items are below: CREATE TABLE `orders` ( `orderid` INT(11) UNSIGNED NOT NULL AUTO_INCREMENT, `memberid` VARCHAR( 20 ), `Time` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP , `info` VARCHAR( 3200 ) NULL , PRIMARY KEY (orderid) , FOREIGN KEY (memberid) REFERENCES members(memberid) ) ENGINE = InnoDB; CREATE TABLE `order_items` ( `orderid` INT(11) UNSIGNED NOT NULL, `item_number_in_cart` tinyint(1) NOT NULL , --- 5 items in cart= 5 rows `price` DECIMAL (6,2) NOT NULL, FOREIGN KEY (orderid) REFERENCES orders(orderid) ) ENGINE = InnoDB; So, order_items table looks like: orderid - item_number_in_cart - price: ... 1000456 - 1 - 24.99 1000456 - 2 - 39.99 1000456 - 3 - 4.99 1000456 - 4 - 17.97 1000457 - 1 - 20.00 1000458 - 1 - 99.99 1000459 - 1 - 2.99 1000459 - 2 - 69.99 1000460 - 1 - 4.99 ... As you see, order_items table has no primary keys (and I think there is no sense to create an auto_increment id for this table, because once we want to extract data, we always extract it as WHERE orderid='1000456' order by item_number_in_card asc - the whole block, id woudn't be helpful in queries). Once data is inserted into order_items, it's not UPDATEd, just SELECTed. The questions are: I think it's a good idea to put index on item_number_in_cart. Could anybody please confirm that? Is there anything else I have to do with order_items to increase the performance, or that looks pretty good? I could miss something because I'm a newbie. Thank you in advance.

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  • How to prevent VC++ 9 linker from linking unnecessary global variables?

    - by sharptooth
    I'm playing with function-level linking in VC++. I've enabled /OPT:REF and /OPT:ICF and the linker is happy to eliminate all unused functions. Not so with variables. The following code is to demonstrate the problem only, I fully understand that actually having code structured that way is suboptimal. //A.cpp SomeType variable1; //B.cpp extern SomeType variable1; SomeType variable2; class ClassInB { //actually uses variable1 }; //C.cpp extern SomeType variable2; class ClassInC { //actually uses variable2; }; All those files are compiled into a static lib. The consumer project only uses ClassInC and links to the static library. Now comes the VC++ 9 linker. First the linker sees that C.obj references variable2 and includes B.obj. B.obj references variable1, so it includes A.obj. Then the unreferenced stuff elimination phase starts. It removes all functions in A.obj and B.obj, but not the variables. Both variable and variable2 are preserved together with their static initializers and deinitializers. That inflates the image size and introduces a delay for running the initializers and deinitializes. The code above is oversimplified, in actual code I really can't move variable2 into C.cpp easily. I could put it into a separate .cpp file, but that looks really dumb. Is there any better option to resolve the problem with Visual C++ 9?

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