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• sharepoint custom aspx page with database connection

  - by Megini

  hi there i have created a custom aspx page whithin my sharepoint site with a sql server connection to a database on that server to select data when i view the page it works but when another user tries to view it it gives the following error : Server Error in '/' Application. Login failed for user 'GRINCOR\GuguK'. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.Data.SqlClient.SqlException: Login failed for user 'GRINCOR\GuguK'. Source Error: The source code that generated this unhandled exception can only be shown when compiled in debug mode. To enable this, please follow one of the below steps, then request the URL: Add a "Debug=true" directive at the top of the file that generated the error. Example: <%@ Page Language="C#" Debug="true" % or: 2) Add the following section to the configuration file of your application: Note that this second technique will cause all files within a given application to be compiled in debug mode. The first technique will cause only that particular file to be compiled in debug mode. Important: Running applications in debug mode does incur a memory/performance overhead. You should make sure that an application has debugging disabled before deploying into production scenario. Stack Trace: [SqlException (0x80131904): Login failed for user 'GRINCOR\GuguK'.] System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) +248 System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) +245 System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj) +2811 System.Data.SqlClient.SqlInternalConnectionTds.CompleteLogin(Boolean enlistOK) +53 System.Data.SqlClient.SqlInternalConnectionTds.AttemptOneLogin(ServerInfo serverInfo, String newPassword, Boolean ignoreSniOpenTimeout, Int64 timerExpire, SqlConnection owningObject) +327 System.Data.SqlClient.SqlInternalConnectionTds.LoginNoFailover(String host, String newPassword, Boolean redirectedUserInstance, SqlConnection owningObject, SqlConnectionString connectionOptions, Int64 timerStart) +2445370 System.Data.SqlClient.SqlInternalConnectionTds.OpenLoginEnlist(SqlConnection owningObject, SqlConnectionString connectionOptions, String newPassword, Boolean redirectedUserInstance) +2445224 System.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, Object providerInfo, String newPassword, SqlConnection owningObject, Boolean redirectedUserInstance) +354 System.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection) +703 System.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnection owningConnection, DbConnectionPool pool, DbConnectionOptions options) +54 System.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject) +2414776 System.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject) +92 System.Data.ProviderBase.DbConnectionPool.GetConnection(DbConnection owningObject) +1657 System.Data.ProviderBase.DbConnectionFactory.GetConnection(DbConnection owningConnection) +84 System.Data.ProviderBase.DbConnectionClosed.OpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory) +1645767 System.Data.SqlClient.SqlConnection.Open() +258 ASP.d7922f0d_ac20_4f87_91a2_a99a52c2b2fa__233736835.DisplayData() in C:\inetpub\wwwroot\wss\VirtualDirectories\80\sites\hrportal2\tester.aspx:151 ASP.d7922f0d_ac20_4f87_91a2_a99a52c2b2fa_233736835._RenderMain(HtmlTextWriter __w, Control parameterContainer) in C:\inetpub\wwwroot\wss\VirtualDirectories\80\sites\hrportal2\tester.aspx:346 System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +115 System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +240 System.Web.UI.HtmlControls.HtmlContainerControl.Render(HtmlTextWriter writer) +42 System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +240 System.Web.UI.HtmlControls.HtmlForm.RenderChildren(HtmlTextWriter writer) +253 System.Web.UI.HtmlControls.HtmlForm.Render(HtmlTextWriter output) +87 System.Web.UI.HtmlControls.HtmlForm.RenderControl(HtmlTextWriter writer) +53 System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +240 System.Web.UI.HtmlControls.HtmlContainerControl.Render(HtmlTextWriter writer) +42 System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +240 System.Web.UI.Control.RenderChildrenInternal(HtmlTextWriter writer, ICollection children) +240 System.Web.UI.Page.Render(HtmlTextWriter writer) +38 System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +4240 Version Information: Microsoft .NET Framework Version:2.0.50727.3603; ASP.NET Version:2.0.50727.3601 can someone give me a solution to this problem ? i am using sharepoint services 3.0

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• MediaPlayer PVMFFailure

  - by kpdvx

  Playing mp3s with the MediaPlayer object, I occasionally get the error "Command PLAYER_INIT completed with an error or info PVMFFailure." Curiously the MediaPlayer documentation doesn't reference this error at all. Anyone familiar with this error and could shed some light on its cause?

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• iOS Application Background Downloading

  - by Hankweb

  Hey! I need to know how I can have my iOS Application start a download in the background of the application (like, have the download run in the AppDelegate file) so changing ViewControllers will not interrupt or cancel the download. I also need to be able to get the progress of the download (0.00000 - 1.00000), to set a UIProgressView object to, which also means I need a - (void)progressDidChangeTo:(int)progress function.

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• Passing Objects between different files

  - by user309779

  Typically, if I want to pass an object to an instance of something I would do it like so... Listing 1 File 1: public class SomeClass { // Some Properties public SomeClass() { public int ID { get { return mID; } set { mID = value; } } public string Name { set { mName = value; } get { return mName; } } } } public class SomeOtherClass { // Method 1 private void Method1(int one, int two) { SomeClass USER; // Create an instance Squid RsP = new Squid(); RsP.sqdReadUserConf(USER); // Able to pass 'USER' to class method in different file. } } In this example, I was not able to use the above approach. Probably because the above example passes an object between classes. Whereas, below, things are defined in a single class. I had to use some extra steps (trial & error) to get things to work. I am not sure what I did here or what its called. Is it good programming practice? Or is there is an easier way to do this (like above). Listing 2 File 1: private void SomeClass1 { [snip] TCOpt_fM.AutoUpdate = optAutoUpdate.Checked; TCOpt_fM.WhiteList = optWhiteList.Checked; TCOpt_fM.BlackList = optBlackList.Checked; [snip] private TCOpt TCOpt_fM; TCOpt_fM.SaveOptions(TCOpt_fM); } File 2: public class TCOpt: { public TCOpt OPTIONS; [snip] private bool mAutoUpdate = true; private bool mWhiteList = true; private bool mBlackList = true; [snip] public bool AutoUpdate { get { return mAutoUpdate; } set { mAutoUpdate = value; } } public bool WhiteList { get { return mWhiteList; } set { mWhiteList = value; } } public bool BlackList { get { return mBlackList; } set { mBlackList = value; } } [snip] public bool SaveOptions(TCOpt OPTIONS) { [snip] Some things being written out to a file here [snip] Squid soSwGP = new Squid(); soSgP.sqdWriteGlobalConf(OPTIONS); } } File 3: public class SomeClass2 { public bool sqdWriteGlobalConf(TCOpt OPTIONS) { Console.WriteLine(OPTIONS.WhiteSites); // Nothing prints here Console.WriteLine(OPTIONS.BlackSites); // Or here } } Thanks in advance, XO

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• Use of infix operator hack in production code (Python)

  - by Casebash

  What is your opinion of using the infix operator hack in production code? Issues: The effect this will have on speed. The potential for a clashes with an object with these operators already defined. This seems particularly dangerous with generic code that is intended to handle objects of any type. It is a shame that this isn't built in - it really does improve readability

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• JSON output of a view in Grails

  - by daliz

  Ok, I have a very simple app created in Grails. I have a generated domain class (Person) and its generated controller, using the automatic Grails scaffold: package contacts class PersonController { def scaffold = Person } Now I'd like to get a JSON representation of a Person object. Do I have to change the view or the controller? And how? Thank you.

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• Create a CBitmap from Resources ID

  - by Smashery

  I need to fill a CImageList with a number of bitmaps which are stored in separate bmp files (rather than as a single bmp with numerous parts). I assume I need to create a CBitmap so I can call the Add method of CImageList. So how might one create a CBitmap object using only MFC Resource IDs?

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• Using matlab, why does something like fts.data work in one directory but not another?

  - by CptanPanic

  I am working with the finacial tooldbox that has a type called FINTS, If I copy some code out of its toolbox directory to customize it, when I try do do something like fts.data, I get The specified field, 'data', does not exist in the object. But the same thing works fine in the matlab library directory. They are both in my path, so what else do I need to change? Thanks.

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• how to create a dynamic sql statement w/ python and mysqldb

  - by Elias Bachaalany

  I have the following code: def sql_exec(self, sql_stmt, args = tuple()): """ Executes an SQL statement and returns a cursor. An SQL exception might be raised on error @return: SQL cursor object """ cursor = self.conn.cursor() if self.__debug_sql: try: print "sql_exec: " % (sql_stmt % args) except: print "sql_exec: " % sql_stmt cursor.execute(sql_stmt, args) return cursor def test(self, limit = 0): result = sql_exec(""" SELECT * FROM table """ + ("LIMIT %s" if limit else ""), (limit, )) while True: row = result.fetchone() if not row: break print row result.close() How can I nicely write test() so it works with or without 'limit' without having to write two queries?

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• "using" keyword in java

  - by DrDro

  In Java is there an equivalent to the C# "using" statement allowing to define a scope for an object: using (AwesomeClass hooray = new AwesomeClass) { // Great code } This has probably allready been asked but the keywords make it difficult to find a relevant question.

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• PHP mysqli error return time

  - by Dori

  Hello. Can i ask a fundamental question. Why when I try to create a new mysqli object in php with invalid database infomation (say an incorrect database name) does it not return an error intstantly? I usually program server stuff in Java and something like this would throw back an error strait away, not after 20 seconds or so. For example $conn = new mysqli($host, $username, $password, $database); Thanks!

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• is there any way we can disable on mouse over event on certain columns of an data grid

  - by prince23

  hi, here wat i am trying to do is that on mouse over of first column i need to hit mouse MouseEnter event and show the pop up which i have kept there rest all other column i dnt need to to show the pop up so i am having this fuction there MouseLeave="Row_MouseLeave" <sdk:DataGrid MinHeight="100" x:Name="dgCounty" AutoGenerateColumns="False" VerticalAlignment="Top" Grid.Row="1" IsReadOnly="True" Margin="5,5,5,0" RowDetailsVisibilityChanged="dgCounty_RowDetailsVisibilityChanged" SelectionMode="Extended" RowDetailsVisibilityMode="VisibleWhenSelected" MouseEnter="dgCounty_MouseEnter" MouseLeave="dgCounty_MouseLeave" SelectionChanged="dgCounty_SelectionChanged" LoadingRow="dgCounty_LoadingRow1" UnloadingRow="dgCounty_UnloadingRow"> <sdk:DataGrid.Columns> <sdk:DataGridTemplateColumn> <sdk:DataGridTemplateColumn.CellTemplate> <DataTemplate> <Button x:Name="myButton" Width="24" Height="24" Click="Details_Click"> <Image x:Name="img" Source="Images/detail.JPG" Stretch="None"/> </Button> </DataTemplate> </sdk:DataGridTemplateColumn.CellTemplate> </sdk:DataGridTemplateColumn> <sdk:DataGridTemplateColumn Header="ID"> <sdk:DataGridTemplateColumn.CellTemplate> <DataTemplate > <sdk:Label Content="{Binding EmployeeID}" /> </DataTemplate> </sdk:DataGridTemplateColumn.CellTemplate> </sdk:DataGridTemplateColumn> <sdk:DataGridTemplateColumn Header="Name"> <sdk:DataGridTemplateColumn.CellTemplate> <DataTemplate > <sdk:Label Content="{Binding EmployeeFName}" MouseLeave="Row_MouseLeave" /> </DataTemplate> </sdk:DataGridTemplateColumn.CellTemplate> </sdk:DataGridTemplateColumn> <sdk:DataGridTemplateColumn Header="MailID"> <sdk:DataGridTemplateColumn.CellTemplate> <DataTemplate > <sdk:Label Content="{Binding EmployeeMailID}" MouseLeave="Row_MouseLeave" /> </DataTemplate> </sdk:DataGridTemplateColumn.CellTemplate> </sdk:DataGridTemplateColumn> </sdk:DataGrid.Columns> </sdk:DataGrid> in code behind void Row_MouseLeave(object sender, MouseEventArgs e) { Show.Visibility = Visibility.Collapsed; PoPGrid.Visibility = Visibility.Collapsed; } void Row_MouseEnter(object sender, MouseEventArgs e) { } the pop up her is like the ajax modal pop up wat we do in asp.net i am able to show data in pop up now the main issue is i need to show pop up only on the 2 column. rest all other column i need to hide the pop up when i move mouse over on that column. i am trying this concept it is not working is there any way i can achive it as i said only need to show pop up on mouse over of the 2 column thanks in advance prince

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• Android - Isn't Eclipse WYSIWYG?

  - by Dada

  Hi at all, i have downloaded Eclipse Galileo and install Android SDK for the first time. I have try to create an simple Userinterface, but i have see that i can't move the "object" directly from the stage. But i need to edit the Code or open the Property panel in order to change the position of an Element on the Stage. Isn't Eclipse WYSIWYG? D.

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• (ActionScript) Change movie clip width with mask

  - by Ronal

  Is there a way to mask a movie clip in a way that alters the width and height of the object? I have a child movie clip that is larger in width so I'm having issues manipulating the width, height and coordinates proportionally of the parent movie clip. I appreciate the help. Thank you.

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• Adding functions to JavaScript View Engine in CouchDB 0.11

  - by fuzzy lollipop

  I want to format dates in a specific format but I can't figure out how to add my date function to the JavasScript view engine in CouchDB. Preferably I would like to add my formatDate() function to the prototype Date object so it is available everywhere Does anyone know how to add this so that the CouchDB JavaScript View engine will see it?

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• What are the benefits of prototypal inheritance over classical?

  - by Pierreten

  So I finally stopped dragging my feet all these years and decided to learn JavaScript "properly". One of the most head-scratching elements of the languages design is it's implementation of inheritance. Having experience in Ruby, I was really happy to see closures and dynamic typing; but for the life of me can't figure out what benefits are to be had from object instances using other instances for inheritance.

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• When i am adding eventHandler on combo in datagridview, its adding eventHandler to all other combo o

  - by Rajesh Rolen- DotNet Developer

  i am using VS2005 (c#.net desktop application). when i am adding eventHandler to a combo of datagridview, its automatically adding same eventhandler to all other combos of same datagridview.. my code: private void dgvtstestdetail_EditingControlShowing(object sender, DataGridViewEditingControlShowingEventArgs e) { DataGridView grid = (sender as DataGridView); if (grid.CurrentCell.OwningColumn == grid.Columns["gdvtstd_TestParameter"]) { ComboBox cb = (e.Control as ComboBox); cb.SelectedIndexChanged -= new EventHandler(dvgCombo_SelectedIndexChanged); cb.SelectedIndexChanged += new EventHandler(dvgCombo_SelectedIndexChanged); } }

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• Making a string out of a string and an integer in Python

  - by Waterfox

  I get this error when trying to take an integer and prepend "b" to it, converting it into a string: File "program.py", line 19, in getname name = "b" + num TypeError: Can't convert 'int' object to str implicitly That's related to this function: num = random.randint(1,25) name = "b" + num

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• Retrieving/Updating Entity Framework POCO objects that already exist in the ObjectContext

  - by jslatts

  I have a project using Entity Framework 4.0 with POCOs (data is stored in SQL DB, lazyloading is enabled) as follows: public class ParentObject { public int ID {get; set;} public virtual List<ChildObject> children {get; set;} } public class ChildObject { public int ID {get; set;} public int ChildRoleID {get; set;} public int ParentID {get; set;} public virtual ParentObject Parent {get; set;} public virtual ChildRoleObject ChildRole {get; set;} } public class ChildRoleObject { public int ID {get; set;} public string Name {get; set;} public virtual List<ChildObject> children {get; set;} } I want to create a new ChildObject, assign it a role, then add it to an existing ParentObject. Afterwards, I want to send the new ChildObject to the caller. The code below works fine until it tries to get the object back from the database. The newChildObjectInstance only has the ChildRoleID set and does not contain a reference to the actual ChildRole object. I try and pull the new instance back out of the database in order to populate the ChildRole property. Unfortunately, in this case, instead of creating a new instance of ChildObject and assigning it to retreivedChildObject, EF finds the existing ChildObject in the context and returns the in-memory instance, with a null ChildRole property. public ChildObject CreateNewChild(int id, int roleID) { SomeObjectContext myRepository = new SomeObjectContext(); ParentObject parentObjectInstance = myRepository.GetParentObject(id); ChildObject newChildObjectInstance = new ChildObject() { ParentObject = parentObjectInstance, ParentID = parentObjectInstance.ID, ChildRoleID = roleID }; parentObjectInstance.children.Add(newChildObjectInstance); myRepository.Save(); ChildObject retreivedChildObject = myRepository.GetChildObject(newChildObjectInstance.ID); string assignedRoleName = retreivedChildObject.ChildRole.Name; //Throws exception, ChildRole is null return retreivedChildObject; } I have tried setting MergeOptions to Overwrite, calling ObjectContext.Refresh() and ObjectContext.DetectChanges() to no avail... I suspect this is related to the proxy objects that EF injects when working with POCOs. Has anyone run into this issue before? If so, what was the solution?

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• Error: java.lang.ClassCastException

  - by theJava

  Updating the entire post. public Login authenticate(Login login) { String query = "SELECT email, id FROM Login WHERE email=? AND password=?"; Object[] parameters = { login.getEmail(), login.getPassword() }; List resultsList = getHibernateTemplate().find(query,parameters); if ( resultsList.size() == 1 ) { results = (Login)resultsList.get(0); System.out.println(results); } else { System.out.println("Error dude.... "); // error no entity or mutiple entities } return results; } I now return Login Objects. private void checkLogin() { form.commit(); Login newUser = new Login(); newUser = ilogin.authenticate(loginbean); System.out.println("Its Null Value" + newUser); if (newUser == null) { getWindow().showNotification("Login failed", LOGIN_ERROR_MSG, Notification.TYPE_WARNING_MESSAGE); } else { System.out.println(newUser); getApplication().setUser(newUser); } } When there is no matching email, i get there is no such user and also this statement does get printed out. System.out.println("Its Null Value" + newUser); But when there is a email and password matching. I get weird error. Caused by: java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to com.intermedix.domain.Login at com.intermedix.services.LoginService.authenticate(LoginService.java:30) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:301) at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:182) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:149) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:106) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204) at $Proxy32.authenticate(Unknown Source) at com.intermedix.ui.LoginDailog.checkLogin(LoginDailog.java:106) at com.intermedix.ui.LoginDailog.access$0(LoginDailog.java:102) at com.intermedix.ui.LoginDailog$1.buttonClick(LoginDailog.java:52) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:487) ... 26 more

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• How do I display a dynamically resized image in Kohana without saving it?

  - by Ygam

  I have an image path string stored in a database It goes like: img/uploads/imagename.jpg I have a controller: $this->image = new Image($wines->image) //this is assuming that I have a wines table with the image property $this->image->resize(60, 250, Image::AUTO) echo $this->image->render(); //the problem is nothing is rendered //Is there a better way of doing this? the image path that I am passing at the Image object //instantiation is the result of a query

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• XML Schema for a .NET type that inherits and implements

  - by John Ruiz

  Hi, Please consider the following three .NET types: I have an interface, an abstract class, and a concrete class. My question is how to write the XML Schema to include the properties from the interface and from the abstract class. public interface IStartable { bool RequiresKey { get; set; } void Start(object key); } public abstract class Vehicle { uint WheelCount { get; set; } } public class Car : Vehicle, IStartable { public bool RequiresKey { get; set; } public string Make { get; set; } publilc string Model { get; set; } public Car() {} public void Start(object key) { // start car with key } } I don't know how to complete this schema: <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace="cars" xmlns="cars" xmlns:c="cars"> <!-- How do I get car to have vehicle's wheelcount AND IStartable's RequiresKey? --> <xs:element name="Car" type="c:Car" /> <xs:complexType name="Car"> <xs:complexContent> <xs:extension base="c:Vehicle"> <xs:group ref=c:CarGroup" /> </xs:extension> </xs:complexContent> </xs:complexType> <xs:group name="CarGroup"> <xs:sequence> <xs:element name="Make" type="xs:token" /> <xs:element name="Model" type="xs:token" /> </xs:sequence> </xs:group> <xs:complexType name="Vehicle"> <xs:sequence> <xs:element name="WheelCount" type="xs:unsignedInt" /> </xs:sequence> </xs:complexType> <xs:complexType name="IStartable"> <xs:sequence> <xs:element name="RequiresKey" type="xs:boolean" /> </xs:sequence> </xs:complexType> </xs:schema>

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• What are the best practices for implementing the == operator for a class in C#?

  - by remio

  While implementing an == operator, I have the feeling that I am missing some essential points. Hence, I am searching some best practices around that. Here are some related questions I am thinking about: How to cleanly handle the reference comparison? Should it be implemented through a IEquatable<T>-like interface? Or overriding object.Equals? And what about the != operator? (this list might not be exhaustive).

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• Speeding up templates in GAE-Py by aggregating RPC calls

  - by Sudhir Jonathan

  Here's my problem: class City(Model): name = StringProperty() class Author(Model): name = StringProperty() city = ReferenceProperty(City) class Post(Model): author = ReferenceProperty(Author) content = StringProperty() The code isn't important... its this django template: {% for post in posts %} <div>{{post.content}}</div> <div>by {{post.author.name}} from {{post.author.city.name}}</div> {% endfor %} Now lets say I get the first 100 posts using Post.all().fetch(limit=100), and pass this list to the template - what happens? It makes 200 more datastore gets - 100 to get each author, 100 to get each author's city. This is perfectly understandable, actually, since the post only has a reference to the author, and the author only has a reference to the city. The __get__ accessor on the post.author and author.city objects transparently do a get and pull the data back (See this question). Some ways around this are Use Post.author.get_value_for_datastore(post) to collect the author keys (see the link above), and then do a batch get to get them all - the trouble here is that we need to re-construct a template data object... something which needs extra code and maintenance for each model and handler. Write an accessor, say cached_author, that checks memcache for the author first and returns that - the problem here is that post.cached_author is going to be called 100 times, which could probably mean 100 memcache calls. Hold a static key to object map (and refresh it maybe once in five minutes) if the data doesn't have to be very up to date. The cached_author accessor can then just refer to this map. All these ideas need extra code and maintenance, and they're not very transparent. What if we could do @prefetch def render_template(path, data) template.render(path, data) Turns out we can... hooks and Guido's instrumentation module both prove it. If the @prefetch method wraps a template render by capturing which keys are requested we can (atleast to one level of depth) capture which keys are being requested, return mock objects, and do a batch get on them. This could be repeated for all depth levels, till no new keys are being requested. The final render could intercept the gets and return the objects from a map. This would change a total of 200 gets into 3, transparently and without any extra code. Not to mention greatly cut down the need for memcache and help in situations where memcache can't be used. Trouble is I don't know how to do it (yet). Before I start trying, has anyone else done this? Or does anyone want to help? Or do you see a massive flaw in the plan?

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• What is the relationship between delegate, proxy and adapter patterns?

  - by Siegfried

  What is the relationship between delegate, proxy and adapter patterns? It seems they are all similar in terms of doing something on behalf of another object. Can anyone summarize the relationship and difference between these 3 patterns? Thanks!

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