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• How to fire server-side methods with jQuery

  - by Nasser Hajloo

  I have a large application and I'm going to enabling short-cut key for it. I'd find 2 JQuery plug-ins (demo plug-in 1 - Demo plug-in 2) that do this for me. you can find both of them in this post in StackOverFlow My application is a completed one and I'm goining to add some functionality to it so I don't want towrite code again. So as a short-cut is just catching a key combination, I'm wonder how can I call the server methods which a short-cut key should fire? So How to use either of these plug-ins, by just calling the methods I'd written before? Actually How to fire Server methods with Jquery? You can also find a good article here, by Dave Ward Update: here is the scenario. When User press CTRL+Del the GridView1_OnDeleteCommand so I have this protected void grdDocumentRows_DeleteCommand(object source, System.Web.UI.WebControls.DataGridCommandEventArgs e) { try { DeleteRow(grdDocumentRows.DataKeys[e.Item.ItemIndex].ToString()); clearControls(); cmdSaveTrans.Text = Hajloo.Portal.Common.Constants.Accounting.Documents.InsertClickText; btnDelete.Visible = false; grdDocumentRows.EditItemIndex = -1; BindGrid(); } catch (Exception ex) { Page.AddMessage(GetLocalResourceObject("AProblemAccuredTryAgain").ToString(), MessageControl.TypeEnum.Error); } } private void BindGrid() { RefreshPage(); grdDocumentRows.DataSource = ((DataSet)Session[Hajloo.Portal.Common.Constants.Accounting.Session.AccDocument]).Tables[AccDocument.TRANSACTIONS_TABLE]; grdDocumentRows.DataBind(); } private void RefreshPage() { Creditors = (decimal)((AccDocument)Session[Hajloo.Portal.Common.Constants.Accounting.Session.AccDocument]).Tables[AccDocument.ACCDOCUMENT_TABLE].Rows[0][AccDocument.ACCDOCUMENT_CREDITORS_SUM_FIELD]; Debtors = (decimal)((AccDocument)Session[Hajloo.Portal.Common.Constants.Accounting.Session.AccDocument]).Tables[AccDocument.ACCDOCUMENT_TABLE].Rows[0][AccDocument.ACCDOCUMENT_DEBTORS_SUM_FIELD]; if ((Creditors - Debtors) != 0) labBalance.InnerText = GetLocalResourceObject("Differentiate").ToString() + "?" + (Creditors - Debtors).ToString(Hajloo.Portal.Common.Constants.Common.Documents.CF) + "?"; else labBalance.InnerText = GetLocalResourceObject("Balance").ToString(); lblSumDebit.Text = Debtors.ToString(Hajloo.Portal.Common.Constants.Common.Documents.CF); lblSumCredit.Text = Creditors.ToString(Hajloo.Portal.Common.Constants.Common.Documents.CF); if (grdDocumentRows.EditItemIndex == -1) clearControls(); } Th other scenario are the same. How to enable short-cut for these kind of code (using session , NHibernate, etc)

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• Constraint Satisfaction Problem

  - by Carl Smotricz

  I'm struggling my way through Artificial Intelligence: A Modern Approach in order to alleviate my natural stupidity. In trying to solve some of the exercises, I've come up against the "Who Owns the Zebra" problem, Exercise 5.13 in Chapter 5. This has been a topic here on SO but the responses mostly addressed the question "how would you solve this if you had a free choice of problem solving software available?" I accept that Prolog is a very appropriate programming language for this kind of problem, and there are some fine packages available, e.g. in Python as shown by the top-ranked answer and also standalone. Alas, none of this is helping me "tough it out" in a way as outlined by the book. The book appears to suggest building a set of dual or perhaps global constraints, and then implementing some of the algorithms mentioned to find a solution. I'm having a lot of trouble coming up with a set of constraints suitable for modelling the problem. I'm studying this on my own so I don't have access to a professor or TA to get me over the hump - this is where I'm asking for your help. I see little similarity to the examples in the chapter. I was eager to build dual constraints and started out by creating (the logical equivalent of) 25 variables: nationality1, nationality2, nationality3, ... nationality5, pet1, pet2, pet3, ... pet5, drink1 ... drink5 and so on, where the number was indicative of the house's position. This is fine for building the unary constraints, e.g. The Norwegian lives in the first house: nationality1 = { :norway }. But most of the constraints are a combination of two such variables through a common house number, e.g. The Swede has a dog: nationality[n] = { :sweden } AND pet[n] = { :dog } where n can range from 1 to 5, obviously. Or stated another way: nationality1 = { :sweden } AND pet1 = { :dog } XOR nationality2 = { :sweden } AND pet2 = { :dog } XOR nationality3 = { :sweden } AND pet3 = { :dog } XOR nationality4 = { :sweden } AND pet4 = { :dog } XOR nationality5 = { :sweden } AND pet5 = { :dog } ...which has a decidedly different feel to it than the "list of tuples" advocated by the book: ( X1, X2, X3 = { val1, val2, val3 }, { val4, val5, val6 }, ... ) I'm not looking for a solution per se; I'm looking for a start on how to model this problem in a way that's compatible with the book's approach. Any help appreciated.

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• Another IKImageView Question: copying a region

  - by Brian Postow

  I'm trying to use the select and copy feature of the IKImageView. If all you want to do is have an app with an image, select a portion and copy it to the clipboard, it's easy. You set the copy menu pick to the first responder's copy:(id) method and magically everything works. However, if you want something more complicated, like you want to copy as part of some other operation, I can't seem to find the method to do this. IKImageView doesn't seem to have a copy method, it doesn't seem to have a method that will even tell you the selected rectangle! I have gone through Hillegass' book, so I understand how the clipboard works, just not how to get the portion of the image out of the view... Now, I'm starting to think that I made a mistake in basing my project on IKImageView, but it's what Preview is built on (or so I've read), so I figured it had to be stable... and anyway, now it's too late, I'm too deep in this to start over... So, other than not using IKImageView, any suggestions on how to copy the select region to the clipboard manually? EDIT actually, I have found the copy(id) method, but when I call it, I get <Error>: CGBitmapContextCreate: unsupported parameter combination: 8 integer bits/component; 16 bits/pixel; 1-component color space; kCGImageAlphaPremultipliedLast; 2624 bytes/row. Which obviously doesn't happen when I do a normal copy through the first-responder... I understand the error message, but I'm not sure where it's getting those parameters from... Is there any way to trace through this and see how this is happening? A debugger won't help for obvious reasons, as well as the fact that I'm doing this in Mozilla, so a debugger isn't an option anyway... EDIT 2 It occurs to me that the copy:(id) method I found may be copying the VIEW rather than copying a chunk of the image to the clipboard, which is what I need. The reason I thought it was the clipboard copy is that in another project, where I'm copying from an IKImageView to the clipboard straight from the edit menu, it just sends a copy:(id) to the firstResponder, but I'm not actually sure what the firstresponder does with it...

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• Unable to execute stored Procedure using Java and JDBC on SQL server

  - by jwmajors81

  I have been trying to execute a MS SQL Server stored procedure via JDBC today and have been unsuccessful thus far. The stored procedure has 1 input and 1 output parameter. With every combination I use when setting up the stored procedure call in code I get an error stating that the stored procedure couldn't be found. I have provided the stored procedure I'm executing below (NOTE: this is vendor code, so I cannot change it). set ANSI_NULLS ON set QUOTED_IDENTIFIER ON GO ALTER PROC [dbo].[spWCoTaskIdGen] @OutIdentifier int OUTPUT AS BEGIN DECLARE @HoldPolicyId int DECLARE @PolicyId char(14) IF NOT EXISTS ( SELECT * FROM UniqueIdentifierGen (UPDLOCK) ) INSERT INTO UniqueIdentifierGen VALUES (0) UPDATE UniqueIdentifierGen SET CurIdentifier = CurIdentifier + 1 SELECT @OutIdentifier = (SELECT CurIdentifier FROM UniqueIdentifierGen) END The code looks like: CallableStatement statement = connection .prepareCall("{call dbo.spWCoTaskIdGen(?)}"); statement.setInt(1, 0); ResultSet result = statement.executeQuery(); I get the following error: SEVERE: Could not find stored procedure 'dbo.spWCoTaskIdGen'. I have also tried CallableStatement statement = connection .prepareCall("{? = call dbo.spWCoTaskIdGen(?)}"); statement.registerOutParameter(1, java.sql.Types.INTEGER); statement.registerOutParameter(2, java.sql.Types.INTEGER); statement.executeQuery(); The above results in: SEVERE: Could not find stored procedure 'dbo.spWCoTaskIdGen'. I have also tried: CallableStatement statement = connection .prepareCall("{? = call spWCoTaskIdGen(?)}"); statement.registerOutParameter(1, java.sql.Types.INTEGER); statement.registerOutParameter(2, java.sql.Types.INTEGER); statement.executeQuery(); The code above resulted in the following error: Could not find stored procedure 'spWCoTaskIdGen'. Finally, I should also point out the following: I have used the MS SQL Server Management Studio tool and have been able to successfully run the stored procedure. The sql generated to execute the stored procedure is provided below: GO DECLARE @return_value int, @OutIdentifier int EXEC @return_value = [dbo].[spWCoTaskIdGen] @OutIdentifier = @OutIdentifier OUTPUT SELECT @OutIdentifier as N'@OutIdentifier ' SELECT 'Return Value' = @return_value GO The code being executed runs with the same user id that was used in point #1 above. In the code that creates the Connection object I log which database I'm connecting to and the code is connecting to the correct database. Any ideas? Thank you very much in advance.

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• Data access pattern, combining push and pull?

  - by andlju

  I need some advice on what kind of pattern(s) I should use for pushing/pulling data into my application. I'm writing a rule-engine that needs to hold quite a large amount of data in-memory in order to be efficient enough. I have some rather conflicting requirements; It is not acceptable for the engine to always have to wait for a full pre-load of all data before it is functional. Only fetching and caching data on-demand will lead to the engine taking too long before it is running quickly enough. An external event can trigger the need for specific parts of the data to be reloaded. Basically, I think I need a combination of pushing and pulling data into the application. A simplified version of my current "pattern" looks like this (in psuedo-C# written in notepad): // This interface is implemented by all classes that needs the data interface IDataSubscriber { void RegisterData(Entity data); } // This interface is implemented by the data access class interface IDataProvider { void EnsureLoaded(Key dataKey); void RegisterSubscriber(IDataSubscriber subscriber); } class MyClassThatNeedsData : IDataSubscriber { IDataProvider _provider; MyClassThatNeedsData(IDataProvider provider) { _provider = provider; _provider.RegisterSubscriber(this); } public void RegisterData(Entity data) { // Save data for later StoreDataInCache(data); } void UseData(Key key) { // Make sure that the data has been stored in cache _provider.EnsureLoaded(key); Entity data = GetDataFromCache(key); } } class MyDataProvider : IDataProvider { List<IDataSubscriber> _subscribers; // Make sure that the data for key has been loaded to all subscribers public void EnsureLoaded(Key key) { if (HasKeyBeenMarkedAsLoaded(key)) return; PublishDataToSubscribers(key); MarkKeyAsLoaded(key); } // Force all subscribers to get a new version of the data for key public void ForceReload(Key key) { PublishDataToSubscribers(key); MarkKeyAsLoaded(key); } void PublishDataToSubscribers(Key key) { Entity data = FetchDataFromStore(key); foreach(var subscriber in _subscribers) { subscriber.RegisterData(data); } } } // This class will be spun off on startup and should make sure that all data is // preloaded as quickly as possible class MyPreloadingThread { IDataProvider _provider; MyPreloadingThread(IDataProvider provider) { _provider = provider; } void RunInBackground() { IEnumerable<Key> allKeys = GetAllKeys(); foreach(var key in allKeys) { _provider.EnsureLoaded(key); } } } I have a feeling though that this is not necessarily the best way of doing this.. Just the fact that explaining it seems to take two pages feels like an indication.. Any ideas? Any patterns out there I should have a look at?

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• Partial overriding in Java (or dynamic overriding while overloading)

  - by Lie Ryan

  If I have a parent-child that defines some method .foo() like this: class Parent { public void foo(Parent arg) { System.out.println("foo in Function"); } } class Child extends Parent { public void foo(Child arg) { System.out.println("foo in ChildFunction"); } } When I called them like this: Child f = new Child(); Parent g = f; f.foo(new Parent()); f.foo(new Child()); g.foo(new Parent()); g.foo(new Child()); the output is: foo in Parent foo in Child foo in Parent foo in Parent But, I want this output: foo in Parent foo in Child foo in Parent foo in Child I have a Child class that extends Parent class. In the Child class, I want to "partially override" the Parent's foo(), that is, if the argument arg's type is Child then Child's foo() is called instead of Parent's foo(). That works Ok when I called f.foo(...) as a Child; but if I refer to it from its Parent alias like in g.foo(...) then the Parent's foo(..) get called irrespective of the type of arg. As I understand it, what I'm expecting doesn't happen because method overloading in Java is early binding (i.e. resolved statically at compile time) while method overriding is late binding (i.e. resolved dynamically at compile time) and since I defined a function with a technically different argument type, I'm technically overloading the Parent's class definition with a distinct definition, not overriding it. But what I want to do is conceptually "partially overriding" when .foo()'s argument is a subclass of the parent's foo()'s argument. I know I can define a bucket override foo(Parent arg) in Child that checks whether arg's actual type is Parent or Child and pass it properly, but if I have twenty Child, that would be lots of duplication of type-unsafe code. In my actual code, Parent is an abstract class named "Function" that simply throws NotImplementedException(). The children includes "Polynomial", "Logarithmic", etc and .foo() includes things like Child.add(Child), Child.intersectionsWith(Child), etc. Not all combination of Child.foo(OtherChild) are solvable and in fact not even all Child.foo(Child) is solvable. So I'm best left with defining everything undefined (i.e. throwing NotImplementedException) then defines only those that can be defined. So the question is: Is there any way to override only part the parent's foo()? Or is there a better way to do what I want to do?

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• Default Database Collations PenTesting Env

  - by dominicdinada

  I am using Ubuntu 9.10 with XAMPP ( Lampp "MYSQL 5.1.45 PHPMYADMIN 3.3.1 PHP 5.3.2 ) What my problem is, is that I set up my testing env to debug my scripts locally and when I did so there arose a problem. This problem is that I used firefox's addon SQLinject ME to test for weakness' and upon doing so it caused mysql to change the default local collations; character sets dir /opt/lampp/share/mysql/charsets/ collation connection latin1_general_ci (Global value) latin1_swedish_ci collation database latin1_swedish_ci collation server latin1_swedish_ci I have searched for quite sometime in regards to a solution to this problem and have come up with searching for the db.opt file which stores this information without success. Upon not finding a solution I removed lampp with the "sudo rm -fR /opt" command and reinstall and the problem still persists. I have tried to change the collations manually and still come up with the database displaying latin1_swedish_ci as the default language. Why is this a problem?? Why is it a problem with mysql? Because the application I am testing and debugging locally is built on the CodeIgnitor with Smarty framework and since this combination of framework is built to detect the LOCALES, Rather what the database defaults are I keep getting errors saying no language file for swedish...... Of course I could get the swedish language file to work around this problem but I do not feel the need to make this work around a perminant solution as with time when I move on to projects I will run into simular problems every time that A; When importing database files, backups etc it will default to import such databases as the locale swedish. B; As time passes on I might completly forget of this error and will be back to square one. I have found this code in searches for a fix,which seems to alter the tables to a desired Collaion; $value) { mysql_query("ALTER TABLE $value COLLATE latin1_general_ci"); }} echo "The collation of your database has been successfully changed!"; ? Which is handy to switch collations in One Schema at a time however this is not a fix when a framework doesnt care that the said database is in one langugae. It tests for the Default of the entire server. Someone with any knowledge of a purge or fix to this I would greatly appricate the help. One more final note is that when I was testing I only figured to back up the applications DataBase and not the entire Schema of the install. No matter if I uninstall or reinstall the database still seems to carry these problems.

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• Unable to execute stored Procedure using Java and JDBC

  - by jwmajors81

  I have been trying to execute a MS SQL Server stored procedure via JDBC today and have been unsuccessful thus far. The stored procedure has 1 input and 1 output parameter. With every combination I use when setting up the stored procedure call in code I get an error stating that the stored procedure couldn't be found. I have provided the stored procedure I'm executing below (NOTE: this is vendor code, so I cannot change it). set ANSI_NULLS ON set QUOTED_IDENTIFIER ON GO ALTER PROC [dbo].[spWCoTaskIdGen] @OutIdentifier int OUTPUT AS BEGIN DECLARE @HoldPolicyId int DECLARE @PolicyId char(14) IF NOT EXISTS ( SELECT * FROM UniqueIdentifierGen (UPDLOCK) ) INSERT INTO UniqueIdentifierGen VALUES (0) UPDATE UniqueIdentifierGen SET CurIdentifier = CurIdentifier + 1 SELECT @OutIdentifier = (SELECT CurIdentifier FROM UniqueIdentifierGen) END The code looks like: CallableStatement statement = connection .prepareCall("{call dbo.spWCoTaskIdGen(?)}"); statement.setInt(1, 0); ResultSet result = statement.executeQuery(); I get the following error: SEVERE: Could not find stored procedure 'dbo.spWCoTaskIdGen'. I have also tried CallableStatement statement = connection .prepareCall("{? = call dbo.spWCoTaskIdGen(?)}"); statement.registerOutParameter(1, java.sql.Types.INTEGER); statement.registerOutParameter(2, java.sql.Types.INTEGER); statement.executeQuery(); The above results in: SEVERE: Could not find stored procedure 'dbo.spWCoTaskIdGen'. I have also tried: CallableStatement statement = connection .prepareCall("{? = call spWCoTaskIdGen(?)}"); statement.registerOutParameter(1, java.sql.Types.INTEGER); statement.registerOutParameter(2, java.sql.Types.INTEGER); statement.executeQuery(); The code above resulted in the following error: Could not find stored procedure 'spWCoTaskIdGen'. Finally, I should also point out the following: I have used the MS SQL Server Management Studio tool and have been able to successfully run the stored procedure. The sql generated to execute the stored procedure is provided below: GO DECLARE @return_value int, @OutIdentifier int EXEC @return_value = [dbo].[spWCoTaskIdGen] @OutIdentifier = @OutIdentifier OUTPUT SELECT @OutIdentifier as N'@OutIdentifier ' SELECT 'Return Value' = @return_value GO The code being executed runs with the same user id that was used in point #1 above. In the code that creates the Connection object I log which database I'm connecting to and the code is connecting to the correct database. Any ideas? Thank you very much in advance.

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• What are the benefits of using ORM over XML Serialization/Deserialization?

  - by Tequila Jinx

  I've been reading about NHibernate and Microsoft's Entity Framework to perform Object Relational Mapping against my data access layer. I'm interested in the benefits of having an established framework to perform ORM, but I'm curious as to the performance costs of using it against standard XML Serialization and Deserialization. Right now, I develop stored procedures in Oracle and SQL Server that use XML Types for either input or output parameters and return or shred XML depending on need. I use a custom database command object that uses generics to deserialize the XML results into a specified serializable class. By using a combination of generics, xml (de)serialization and Microsoft's DAAB, I've got a process that's fairly simple to develop against regardless of the data source. Moreover, since I exclusively use Stored Procedures to perform database operations, I'm mostly protected from changes in the data structure. Here's an over-simplified example of what I've been doing. static void main() { testXmlClass test = new test(1); test.Name = "Foo"; test.Save(); } // Example Serializable Class ------------------------------------------------ [XmlRootAttribute("test")] class testXmlClass() { [XmlElement(Name="id")] public int ID {set; get;} [XmlElement(Name="name")] public string Name {set; get;} //create an instance of the class loaded with data. public testXmlClass(int id) { GenericDBProvider db = new GenericDBProvider(); this = db.ExecuteSerializable("myGetByIDProcedure"); } //save the class to the database... public Save() { GenericDBProvider db = new GenericDBProvider(); db.AddInParameter("myInputParameter", DbType.XML, this); db.ExecuteSerializableNonQuery("mySaveProcedure"); } } // Database Handler ---------------------------------------------------------- class GenericDBProvider { public T ExecuteSerializable<T>(string commandText) where T : class { XmlSerializer xml = new XmlSerializer(typeof(T)); // connection and command code is assumed for the purposes of this example. // the final results basically just come down to... return xml.Deserialize(commandResults) as T; } public void ExecuteSerializableNonQuery(string commandText) { // once again, connection and command code is assumed... // basically, just execute the command along with the specified // parameters which have been serialized. } public void AddInParameter(string name, DbType type, object value) { StringWriter w = new StringWriter(); XmlSerializer x = new XmlSerializer(value.GetType()); //handle serialization for serializable classes. if (type == DbType.Xml && (value.GetType() != typeof(System.String))) { x.Serialize(w, value); w.Close(); // store serialized object in a DbParameterCollection accessible // to my other methods. } else { //handle all other parameter types } } } I'm starting a new project which will rely heavily on database operations. I'm very curious to know whether my current practices will be sustainable in a high-traffic situation and whether or not I should consider switching to NHibernate or Microsoft's Entity Framework to perform what essentially seems to boil down to the same thing I'm currently doing. I appreciate any advice you may have.

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• Giving event control back to xaml/callee to access check/uncheck

  - by dovholuk

  Hi All, I've scoured the Internet but my search-foo must not work if it's out there cause I just can't find the proper search terms to get me the answer I am looking for. So I turn to the experts here as a last resort to point me in the right direction. What I'm trying to do is create a composite control of a text box and a list box but I want to allow the control consumer to decide what to do when say the checkbox is checked/unchecked and I just can't figure it out... Maybe i'm going about it all wrong. What I've done thus far is to: create a custom control that extends ListBox expose a custom DP named "Text" (for the Text box but it's not the important part) craft the generic.xaml so that the list items have a default ItemTemplate/DataTemplate inside the DataTemplate I'm trying to set the "Checked" or "Unchecked" events expose 'wrapper' events as DPs in the custom control that would get 'set' via the template when instatiated As soon as I try something like the following (inside generic.xaml): <DataTemplate> <...> <CheckBox Checked="{TemplateBinding MyCheckedDP}"/> <...> </DataTemplate> I get runtime exceptions, the designer - vs2010 - pukes out a LONG list of errors that are all very similar and nothing I do can make it work. I went so far as to try using the VisualTreeHelper but no magic combination I could find would work nor would it allow me to traverse the tree because when the OnApplyTemplate method fires the listbox items don't exist yet and aren't in the tree. So hopefully this all makes sense but if not please let me know and I'll edit the post for clarifications. Thanks to all for any pointers or thoughts... Like I said maybe I'm heading about it in the wrong way from the start... EDIT (Request for xaml) generic.xaml datatemplate: <DataTemplate > <StackPanel Orientation="Horizontal" > <local:FilterCheckbox x:Name="chk"> <TextBlock Text="{Binding Path=Display}" /> </local:FilterCheckbox> </StackPanel> </DataTemplate> usercontrol.xaml (invocation of custom control) <local:MyControl FancyName="This is the fancy name" ItemChecked="DoThisWhenACheckboxIsChecked" <-- this is where the consumer "ties" to the checkbox events ItemsSource="{Binding Source={StaticResource someDataSource}}" />

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• Exception opening TAdoDataset: Arguments are of the wrong type, are out of acceptable range, or are

  - by Dave Falkner

  I've been trying to debug the following problem for several weeks now - this method is called from several places within the same datamodule, but this exception (from the subject line of this post) only occurs when integers for a certain purpose (pickup orders vs. orders that we ship through a carrier) are used - and don't ask me how the application can tell the difference between one integer's purpose and another! Furthermore, I cannot duplicate this issue on my machine - the error occurs on a warehouse machine but not my own development machine, even when working with the same production database. I have suspected an MDAC version conflict between the two machines, but have run a version checker and confirmed that both machines are running 2.8, and additionally have confirmed this by logging the TAdoDataset's .Version property at runtime. function TdmESShip.SecondaryID(const PrimaryID : Integer ): String; begin try with qESPackage2 do begin if Active then Close; LogMessage('-----------------------------------'); LogMessage('Version: ' + FConnection.Version); LogMessage('DB Info: ' + FConnection.Properties['Initial Catalog'].Value + ' ' + FConnection.Properties['Data Source'].Value); LogMessage('Setting the parameter.'); Parameters.ParamByName('ParameterName').Value := PrimaryID; LogMessage('Done setting the parameter.'); Open; Ninety-nine times out of 100 this logging code logs a successful operation as follows: Version: 2.8 DB Info: (database name and instance) Setting the parameter. Done setting the parameter. Opened the dataset. But then whenever a "pickup" order is processed, this exception gets thrown whenever the dataset is opened: Version: 2.8 DB Info: (database name and instance) Setting the parameter. Done setting the parameter. GetESPackageID() threw an exception. Type: EOleException, Message: Arguments are of the wrong type, are out of acceptable range, or are in conflict with one another Error: Arguments are of the wrong type, are out of acceptable range, or are in conflict with one another for packageID 10813711 I've tried eliminating the parameter and have built the commandtext for this dataset programmatically, suspecting that some part of the TParameter's configuration might be out of whack, but the same error occurs under the same circumstances. I've tried every combination of TParameter properties that I can think of - this is the millionth TParameter I've created for my millionth dataset, and I've never encountered this error. I've even created a second dataset from scratch and removed all references to the original dataset in case some property of the original dataset in the .dfm might be corrupted, but the same error occurs under the same circumstances. The commandtext for this dataset is a simple select ValueA from TableName where ValueB = @ParameterB I'm about ready to do something extreme, such as writing a web service to look these values up - it feels right now as though I could destroy my machine, rebuild it, rewrite this entire application from scratch, and the application would still know to throw an exception whenever I try to look up a secondary value from a primary value, but only for pickup orders, and only from the one machine in the warehouse, but I'm probably missing something simple. So, any help anyone could provide would be greatly appreciated.

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• SharedObject (Flex 3.2) behaving unexpectedly when query string present in URL

  - by rhtx

  Summary: The behavior detailed below seems to indicate that if your app at www.someplace.com sets/retrieves data via a SharedObject, there is some sort of .sol collision if the user hits your app at someplace.com, and then later at someplace.com?name=value. Can anyone confirm or refute this? I'm working on a Flex web app that presents the user with a login page. When the user has logged in, he/she is presented with a 'room' which is associated with a 'group'. We store the last-visited room/group combination in a SharedObject - so when a given user logs in, they are taken into the most recent room in which they were active. That works fine, but we also have an auto-login system which involves the user clicking on a link to the app url with a query string attached. There are two types of these links. 1) the query string includes username, groupId, and roomId 2) the query string includes only the username Because we are working fast and have only a few developers, the auto-login system is built on the last-vist system. During the auto-login process, the url is inspected and if groupId and roomId values are found in the query string, the SharedObject is opened and the last-visit group/room id values are overwritten by the param values. That works fine, also, when the app is hit with a query string of the second type (no groupId and roomId params), the app goes to the SharedObject to get the stored room and group id values, as it normally would. And here's the problem: The values it comes back with are whatever the last room/group param values were, not whatever the last last-visit room/group values are. And if the given user has never hit the app with query string that included group and room id values, the app gets null values from the SharedObject. It took some digging around, but what it looks like is happening is that a second set of data is being stored/expected in the SharedObject if a query string is present in the URL. Looking at the .sol file in a text editor I see more untranslated code, and additional group and room values, once I've hit the app with URLs that contain query strings. I'm not finding anything on the web about this, but that may just be due to a lack of necessary search skills. Has anyone else run into anything similar? Or do you know how to address this? I've tried setting Security.exactSettings to false, already - was really hoping that was going to work.

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• Sanity check on this idea for an Image Viewer in a web app

  - by Charlie Flowers

  I have an approach in mind for an image viewer in a web app, and want to get a sanity check and any thoughts you stackoverflowers might have. Here's the whirlwind nutshell summary: I'm working on an ASP.NET MVC application that will run in my company's retail stores. Even though it is a web application, we own the store machines and have control over them. We have a "windows agent" running on the store machine which we can talk to via http post (it is a WCF service, and our web app has permission to talk to it from the browser). One of the web pages needs to be an "image viewer" page with some common things like Rotate & Zoom. Now, there are some WebForms controls that offer Rotate and Zoom. However, they take up server resources and generate a good bit of traffic between the server and the browser. For example, the Rotate function would cause an ajax call to the server, which would then generate a new image written to a .NET Canvas object, which would then be written to a file on the server, which would then be returned from the ajax call and refreshed inside the browser. Normally, that's a pretty good way of doing things. But in our case, we have code running on the store machine that we can communicate with. This leads me to consider the following approach: When the user asks to view an image, we tell our "windows agent" to download it from our image server to the store machine. We then redirect our browser to our image viewer page, which will pull the image from the local file we just wrote to the store machine. When the user clicks "Rotate", we cause JavaScript code in the browser to call our "windows agent" software, asking it to perform the "Rotate" function. The "windows agent" does the rotation using the same kind of imaging control that would formerly have been used on the server, but it does so now on the store machine. Javascript in the browser then refreshes the image on the page to show the newly rotated image. Zoom and similar features would be implemented the same way. This seems to be much more efficient, scalable, and responsive for the end-users. However, I've never heard of anything like it being done, mostly because it's rare to have this combination of a web app plus a "windows agent" on the client machine. What do you think? Feasible? Reasonable? Any pitfalls I overlooked or improvements / suggestions you can see? Has anyone done anything like this who would like to offer the wisdom of experience? Thanks!

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• Troubleshooting Multiple Endpoints Problem in WCF

  - by omatase

  I have been using WCF for a few years now and am fairly comfortable with it, however there is one simple WCF concept that I have yet to employ and am having difficulties with it. Following this article about WCF addressing as it specifically relates to multiple endpoints in IIS I see these two excerpts: "Suppose you have a file named calc.svc and you place it in a virtual directory that corresponds to (http://localhost:8080/calcservice). The base address for this service will be (http://localhost:8080/calcservice/calc.svc)." and "Now, consider the endpoint configuration found in the virtual directory’s web.config file (in Figure 3). In this case, the address of the first endpoint becomes the same as the base address (http://localhost:8080/calcservice/calc.svc) since I left the endpoint address empty. The address of the second endpoint becomes the combination of the base address appended with "secure", like this: (http://localhost:8080/calcservice/calc.svc/secure)." Now in my application I'm trying to create two endpoints for the same service (shown below). The service name is MainService.svc. For endpoint one I have address="" and endpoint two has address="Soap11". Bringing the site up in IIS I can successfully hit this URL: (https://localhost:444/MainService.svc). This is the base address for the service according to all the documentation I can find. According to this article and others I have seen that confirm its information I should have the second endpoint at (https://localhost:444/MainService.svc/Soap11) but if I navigate to that URL I get a .Net exception indicating the resource is not found. Is there a tool I can use to see where my different endpoints will be available? Maybe some IIS or aspnet_isapi.dll logging I can turn on? My web.config section defining my endpoints follows. Thanks in advance for your help <service behaviorConfiguration="MyService.MainServiceBehavior" name="MyService.MainService"> <endpoint address="" binding="wsHttpBinding" bindingConfiguration="WSBindingConfig" contract="MyService.IMainService"> <identity> <dns value="localhost" /> </identity> </endpoint> <endpoint address="Soap11" binding="basicHttpBinding" bindingConfiguration="BasicBindingWithCredentials" contract="MyService.IMainService"> <identity> <dns value="localhost" /> </identity> </endpoint> <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange" /> </service>

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• :contains for multiple words

  - by Emin

  I am using the following jQuery var etag='kate' if (etag.length > 0) { $('div').each(function () { $(this).find('ul:not(:contains(' + etag + '))').hide(); $(this).find('ul:contains(' + etag + ')').show(); }); }? towards the following HTML <div id="2"> <ul> <li>john</li> <li>jack</li> </ul> <ul> <li>kate</li> <li>clair</li> </ul> <ul> <li>hugo</li> <li>desmond</li> </ul> <ul> <li>said</li> <li>jacob</li> </ul> </div> <div id="3"> <ul> <li>jacob</li> <li>me</li> </ul> <ul> <li>desmond</li> <li>george</li> </ul> <ul> <li>allen</li> <li>kate</li> </ul> <ul> <li>salkldf</li> <li>3kl44</li> </ul> </div> basically, as long as etag has one word, the code works perfectly and hides those elements who do not contain etag. My problem is, when etag is multiple words (and I don't have control over it. Its coming from a database and could be combination of multiple words seperated with space char) then the code does not work.. is there any way to achieve this?

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• C# Extend array type to overload operators

  - by Episodex

  I'd like to create my own class extending array of ints. Is that possible? What I need is array of ints that can be added by "+" operator to another array (each element added to each), and compared by "==", so it could (hopefully) be used as a key in dictionary. The thing is I don't want to implement whole IList interface to my new class, but only add those two operators to existing array class. I'm trying to do something like this: class MyArray : Array<int> But it's not working that way obviously ;). Sorry if I'm unclear but I'm searching solution for hours now... UPDATE: I tried something like this: class Zmienne : IEquatable<Zmienne> { public int[] x; public Zmienne(int ilosc) { x = new int[ilosc]; } public override bool Equals(object obj) { if (obj == null || GetType() != obj.GetType()) { return false; } return base.Equals((Zmienne)obj); } public bool Equals(Zmienne drugie) { if (x.Length != drugie.x.Length) return false; else { for (int i = 0; i < x.Length; i++) { if (x[i] != drugie.x[i]) return false; } } return true; } public override int GetHashCode() { int hash = x[0].GetHashCode(); for (int i = 1; i < x.Length; i++) hash = hash ^ x[i].GetHashCode(); return hash; } } Then use it like this: Zmienne tab1 = new Zmienne(2); Zmienne tab2 = new Zmienne(2); tab1.x[0] = 1; tab1.x[1] = 1; tab2.x[0] = 1; tab2.x[1] = 1; if (tab1 == tab2) Console.WriteLine("Works!"); And no effect. I'm not good with interfaces and overriding methods unfortunately :(. As for reason I'm trying to do it. I have some equations like: x1 + x2 = 0.45 x1 + x4 = 0.2 x2 + x4 = 0.11 There are a lot more of them, and I need to for example add first equation to second and search all others to find out if there is any that matches the combination of x'es resulting in that adding. Maybe I'm going in totally wrong direction?

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• Executing a .NET Managed Assembly from SQL Server 2008 - Pro's, Con's & Recommendations

  - by RPM1984

  Hi guys, looking for opinions/recommendations/links for the following scenario im currently facing. The Platform: .NET 4.0 Web Application SQL Server 2008 The Task: Overhaul a component of the system that performs (fairly) complex mathematical operations based on a specific user activity, and updates numerous tables in the database. A common user activity might be "Bob" decides to post a forum topic. This results in (the end-solution) needing to look at various factors (about the post he did), then after doing some math based on lookup values/ratios as well as other data in the database, inserting some other data as a result of these operations. The Options: Ok - so here's what im thinking. Although it would be much easier to do this in C# (LINQ-SQL) it doesnt make much sense as the majority of the computations are based on values in the db, and it will get difficult to control/optimize/debug the LINQ over time. Hence, im leaning towards created a managed assembly (C# Class Library) that contains the lookup values (constants) as well as leveraging the math classes in the existing .NET BCL. Basically i'd expose a few methods that can be called by the T-SQL Stored Procedures. This to me has the following advantages: Simplicity of math. Do complex math in .NET vs complex math in T-SQL. No brainer. =) Abstraction of computatations, configurable "lookup" values and business logic from raw T-SQL. T-SQL only needs to care about the data, simplifying the stored procedures and making it easier to maintain. When it needs to do math it delegates off to the managed assembly. So, having said that - ive never done this before (call .NET assmembly from T-SQL), and after some googling the best site i could come up with is here, which is useful but outdated. So - what am i asking? Well, firstly - i need some better references on how to actually do this. "This" being how to call a C# .NET 4 Assembly from within T-SQL Stored Procedures in SQL Server 2008. Secondly, who out there has done this, what problems (if any) did you face? Realize this may be difficult to provide a "correct answer", so ill try to give it to whoever gives me the answer with a combination of good links and a list of pro's/con's/problems with this implementation. Cheers!

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• Need help iteratating over an array, retrieve two possibilites, no repeats, for Poker AI

  - by elguapo-85

  Can't really think of a good way to word this question, nor a good title, and maybe the answer is so ridiculously simple that I am missing it. I am working on a poker AI, and I want to calculate the number of hands that exist which are better then mine, I understand how to that, but want I can't figure out is the best way to iterate over a group of cards. So I am at the flop, I know what my two cards are and there are 3 cards on the board. So there are 47 unknown cards and I want to iterate over all possible combination of those 47 cards assuming that two are passed out, so you can't have two cards of the same rank and suit, and you if you have previously calculated a set you don't want to do it over again, because I will being wasting time, and this will be called many times. If you don't understand want I am asking please tell me and I will clarify more. So I can set something up like this, if that element equals one, it means it is not in my hand and not on the board, 4 for each suit, and 13 for each rank. setOfCards[4][13] If I do a simple set of for loops like this: (pseudocode) //remove cards I know are in play from setOfCards by setting values to zero for(int i = 0; i < 4; i++) for(int j = 0; j < 13; j++) for(int k = 0; k < 4; k++) for(int l = 0; l < 4; l++) //skip if values equal zero card1 = setOfCards[i][j] card2 = setOfCards[k][l] //now compare card1, card2 and set of board cards So this is actually going to repeat many values, for example: card1 = AceOfHearts, card2 = KingOfHearts is the same as card1 = KingOfHearts, card2 = AceOfHearts. It will also alter my calculations. How should I go about avoiding this? Also is there a name for this technique? Thank you.

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• SQLite bulk insert on iPhone not working

  - by App_beginner

  Hi. I have been struggling with this seeminly easy problem for 48 hours, and I am no closer to a solution. So I was hoping that someone might be able to help me. I am building a app, that use a combination of a local (SQLite) database and an online database (PHP/MYSQL). The app is nearly finished. Checked for leaks and work like a charm. However the very last part is the part I have struggled with. On launch, I want the app to check for changes to the online databse, and if there is. I want it to download and parse a xml file containing the changes. Everything is working fine this far. But when I try to bulk insert my parsed data to my database, the app crashes, giving a NSInternalInconsistency error. Due to the database returning SQLITE_MISUSE. I have done a lot of googling, but am still unable to solve my problem. So I am putting the code here, hoping that someone can help me fix this. And I know that I should have used core data for this. But this is the very last part I am struggling with, and I am very reluctant to changing my entire code now. Core data will have to come in the update. Here is the error I recieve: Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Error while inserting data. 'library routine called out of sequence'' Here is my code: -(void)UpdateDatabase:(const char *)_query NewValues:(NSMutableArray *)_odb dbn:(NSString *)_dbn dbp:(NSString *)_dbp { sqlite3 *database; NSMutableArray *NewValues = _odb; int i; const char *query = _query; sqlite3_stmt *addStmt; for (i = 1; i < [NewValues count]; i++) { if(sqlite3_prepare_v2(database, query, -1, &addStmt, NULL) == SQLITE_OK) { sqlite3_bind_text(addStmt, 1, [[[NewValues objectAtIndex:i] name] UTF8String], -1, SQLITE_TRANSIENT); sqlite3_bind_text(addStmt, 2, [[[NewValues objectAtIndex:i] city]UTF8String], -1, SQLITE_TRANSIENT); sqlite3_bind_double(addStmt, 3, [[[NewValues objectAtIndex:i] lat] doubleValue]); sqlite3_bind_int(addStmt, 4, [[[NewValues objectAtIndex:i] long] doubleValue]); sqlite3_bind_int(addStmt, 5, [[[NewValues objectAtIndex:i] code] intValue]); } if(SQLITE_DONE != sqlite3_step(addStmt)) { NSAssert1(0, @"Error while inserting data. '%s'", sqlite3_errmsg(database)); } //Reset the add statement. sqlite3_reset(addStmt); } }

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• Deterministic key serialization

  - by Mike Boers

  I'm writing a mapping class which uses SQLite as the storage backend. I am currently allowing only basestring keys but it would be nice if I could use a couple more types hopefully up to anything that is hashable (ie. same requirements as the builtin dict). To that end I would like to derive a deterministic serialization scheme. Ideally, I would like to know if any implementation/protocol combination of pickle is deterministic for hashable objects (e.g. can only use cPickle with protocol 0). I noticed that pickle and cPickle do not match: >>> import pickle >>> import cPickle >>> def dumps(x): ... print repr(pickle.dumps(x)) ... print repr(cPickle.dumps(x)) ... >>> dumps(1) 'I1\n.' 'I1\n.' >>> dumps('hello') "S'hello'\np0\n." "S'hello'\np1\n." >>> dumps((1, 2, 'hello')) "(I1\nI2\nS'hello'\np0\ntp1\n." "(I1\nI2\nS'hello'\np1\ntp2\n." Another option is to use repr to dump and ast.literal_eval to load. This would only be valid for builtin hashable types. I have written a function to determine if a given key would survive this process (it is rather conservative on the types it allows): def is_reprable_key(key): return type(key) in (int, str, unicode) or (type(key) == tuple and all( is_reprable_key(x) for x in key)) The question for this method is if repr itself is deterministic for the types that I have allowed here. I believe this would not survive the 2/3 version barrier due to the change in str/unicode literals. This also would not work for integers where 2**32 - 1 < x < 2**64 jumping between 32 and 64 bit platforms. Are there any other conditions (ie. do strings serialize differently under different conditions)? (If this all fails miserably then I can store the hash of the key along with the pickle of both the key and value, then iterate across rows that have a matching hash looking for one that unpickles to the expected key, but that really does complicate a few other things and I would rather not do it.) Any insights?

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• Mocking HtmlHelper throws NullReferenceException

  - by Matt Austin

  I know that there are a few questions on StackOverflow on this topic but I haven't been able to get any of the suggestions to work for me. I've been banging my head against this for two days now so its time to ask for help... The following code snippit is a simplified unit test to demonstrate what I'm trying to do, which is basically call RadioButtonFor in the Microsoft.Web.Mvc assembly in a unit test. var model = new SendMessageModel { SendMessageType = SendMessageType.Member }; var vd = new ViewDataDictionary(model); vd.TemplateInfo = new TemplateInfo { HtmlFieldPrefix = string.Empty }; var controllerContext = new ControllerContext(new Mock<HttpContextBase>().Object, new RouteData(), new Mock<ControllerBase>().Object); var viewContext = new Mock<ViewContext>(new object[] { controllerContext, new Mock<IView>().Object, vd, new TempDataDictionary(), new Mock<TextWriter>().Object }); viewContext.Setup(v => v.View).Returns(new Mock<IView>().Object); viewContext.Setup(v => v.ViewData).Returns(vd).Callback(() => {throw new Exception("ViewData extracted");}); viewContext.Setup(v => v.TempData).Returns(new TempDataDictionary()); viewContext.Setup(v => v.Writer).Returns(new Mock<TextWriter>().Object); viewContext.Setup(v => v.RouteData).Returns(new RouteData()); viewContext.Setup(v => v.HttpContext).Returns(new Mock<HttpContextBase>().Object); viewContext.Setup(v => v.Controller).Returns(new Mock<ControllerBase>().Object); viewContext.Setup(v => v.FormContext).Returns(new FormContext()); var mockContainer = new Mock<IViewDataContainer>(); mockContainer.Setup(x => x.ViewData).Returns(vd); var helper = new HtmlHelper<ISendMessageModel>(viewContext.Object, mockContainer.Object, new RouteCollection()); helper.RadioButtonFor(m => m.SendMessageType, "Member", cssClass: "selector"); If I remove the cssClass parameter then the code works ok but fails consistently when adding additional parameters. I've tried every combination of mocking, instantiating concrete types and using fakes that I can think off but I always get a NullReferenceException when I call RadioButtonFor. Any help hugely appreciated!!

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• Smoke testing a .NET web application

  - by pdr

  I cannot believe I'm the first person to go through this thought process, so I'm wondering if anyone can help me out with it. Current situation: developers write a web site, operations deploy it. Once deployed, a developer Smoke Tests it, to make sure the deployment went smoothly. To me this feels wrong, it essentially means it takes two people to deploy an application; in our case those two people are on opposite sides of the planet and timezones come into play, causing havoc. But the fact remains that developers know what the minimum set of tests is and that may change over time (particularly for the web service portion of our app). Operations, with all due respect to them (and they would say this themselves), are button-pushers who need a set of instructions to follow. The manual solution is that we document the test cases and operations follow that document each time they deploy. That sounds painful, plus they may be deploying different versions to different environments (specifically UAT and Production) and may need a different set of instructions for each. On top of this, one of our near-future plans is to have an automated daily deploy environment, so then we'll have to instruct a computer as to how to deploy a given version of our app. I would dearly like to add to that instructions for how to smoke test the app. Now developers are better at documenting instructions for computers than they are for people, so the obvious solution seems to be to use a combination of nUnit (I know these aren't unit tests per se, but it is a built-for-purpose test runner) and either the Watin or Selenium APIs to run through the obvious browser steps and call to the web service and explain to the Operations guys how to run those unit tests. I can do that; I have mostly done it already. But wouldn't it be nice if I could make that process simpler still? At this point, the Operations guys and the computer are going to have to know which set of tests relate to which version of the app and tell the nUnit runner which base URL it should point to (say, www.example.com = v3.2 or test.example.com = v3.3). Wouldn't it be nicer if the test runner itself had a way of giving it a base URL and letting it download say a zip file, unpack it and edit a configuration file automatically before running any test fixtures it found in there? Is there an open source app that would do that? Is there a need for one? Is there a solution using something other than nUnit, maybe Fitnesse? For the record, I'm looking at .NET-based tools first because most of the developers are primarily .NET developers, but we're not married to it. If such a tool exists using other languages to write the tests, we'll happily adapt, as long as there is a test runner that works on Windows.

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• Question about Architecture for Viewing Images in ASP.NET MVC App

  - by Charlie Flowers

  I have an approach in mind for an image viewer in a web app, and want to get a sanity check and any thoughts you stackoverflowers might have. Here's the whirlwind nutshell summary: I'm working on an ASP.NET MVC application that will run in my company's retail stores. Even though it is a web application, we own the store machines and have control over them. We have a "windows agent" running on the store machine which we can talk to from the browser via javascript (it is a WCF service, and our web app has permission to talk to it from the browser). One of the web pages needs to be an "image viewer" page with some common things like Rotate & Zoom. Now, there are some WebForms controls that offer Rotate and Zoom. However, they take up server resources and generate a good bit of traffic between the server and the browser. For example, the Rotate function would cause an ajax call to the server, which would then generate a new image written to a .NET Canvas object, which would then be written to a file on the server, which would then be returned from the ajax call and refreshed inside the browser. Normally, that's a pretty good way of doing things. But in our case, we have code running on the store machine that we can communicate with. This leads me to consider the following approach: When the user asks to view an image, we tell our "windows agent" to download it from our image server to the store machine. We then redirect our browser to our image viewer page, which will pull the image from the local file we just wrote to the store machine. When the user clicks "Rotate", we cause JavaScript code in the browser to call our "windows agent" software, asking it to perform the "Rotate" function. The "windows agent" does the rotation using the same kind of imaging control that would formerly have been used on the server, but it does so now on the store machine. Javascript in the browser then refreshes the image on the page to show the newly rotated image. Zoom and similar features would be implemented the same way. This seems to be much more efficient, scalable, and responsive for the end-users. However, I've never heard of anything like it being done, mostly because it's rare to have this combination of a web app plus a "windows agent" on the client machine. What do you think? Feasible? Reasonable? Any pitfalls I overlooked or improvements / suggestions you can see? Has anyone done anything like this who would like to offer the wisdom of experience? Thanks!

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• What are the Options for Storing Hierarchical Data in a Relational Database?

  - by orangepips

  Good Overviews One more Nested Intervals vs. Adjacency List comparison: the best comparison of Adjacency List, Materialized Path, Nested Set and Nested Interval I've found. Models for hierarchical data: slides with good explanations of tradeoffs and example usage Representing hierarchies in MySQL: very good overview of Nested Set in particular Hierarchical data in RDBMSs: most comprehensive and well organized set of links I've seen, but not much in the way on explanation Options Ones I am aware of and general features: Adjacency List: Columns: ID, ParentID Easy to implement. Cheap node moves, inserts, and deletes. Expensive to find level (can store as a computed column), ancestry & descendants (Bridge Hierarchy combined with level column can solve), path (Lineage Column can solve). Use Common Table Expressions in those databases that support them to traverse. Nested Set (a.k.a Modified Preorder Tree Traversal) First described by Joe Celko - covered in depth in his book Trees and Hierarchies in SQL for Smarties Columns: Left, Right Cheap level, ancestry, descendants Compared to Adjacency List, moves, inserts, deletes more expensive. Requires a specific sort order (e.g. created). So sorting all descendants in a different order requires additional work. Nested Intervals Combination of Nested Sets and Materialized Path where left/right columns are floating point decimals instead of integers and encode the path information. Bridge Table (a.k.a. Closure Table: some good ideas about how to use triggers for maintaining this approach) Columns: ancestor, descendant Stands apart from table it describes. Can include some nodes in more than one hierarchy. Cheap ancestry and descendants (albeit not in what order) For complete knowledge of a hierarchy needs to be combined with another option. Flat Table A modification of the Adjacency List that adds a Level and Rank (e.g. ordering) column to each record. Expensive move and delete Cheap ancestry and descendants Good Use: threaded discussion - forums / blog comments Lineage Column (a.k.a. Materialized Path, Path Enumeration) Column: lineage (e.g. /parent/child/grandchild/etc...) Limit to how deep the hierarchy can be. Descendants cheap (e.g. LEFT(lineage, #) = '/enumerated/path') Ancestry tricky (database specific queries) Database Specific Notes MySQL Use session variables for Adjacency List Oracle Use CONNECT BY to traverse Adjacency Lists PostgreSQL ltree datatype for Materialized Path SQL Server General summary 2008 offers HierarchyId data type appears to help with Lineage Column approach and expand the depth that can be represented.

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• Normalizing Item Names & Synonyms

  - by RabidFire

  Consider an e-commerce application with multiple stores. Each store owner can edit the item catalog of his store. My current database schema is as follows: item_names: id | name | description | picture | common(BOOL) items: id | item_name_id | picture | price | description | picture item_synonyms: id | item_name_id | name | error(BOOL) Notes: error indicates a wrong spelling (eg. "Ericson"). description and picture of the item_names table are "globals" that can optionally be overridden by "local" description and picture fields of the items table (in case the store owner wants to supply a different picture for an item). common helps separate unique item names ("Jimmy Joe's Cheese Pizza" from "Cheese Pizza") I think the bright side of this schema is: Optimized searching & Handling Synonyms: I can query the item_names & item_synonyms tables using name LIKE %QUERY% and obtain the list of item_name_ids that need to be joined with the items table. (Examples of synonyms: "Sony Ericsson", "Sony Ericson", "X10", "X 10") Autocompletion: Again, a simple query to the item_names table. I can avoid the usage of DISTINCT and it minimizes number of variations ("Sony Ericsson Xperia™ X10", "Sony Ericsson - Xperia X10", "Xperia X10, Sony Ericsson") The down side would be: Overhead: When inserting an item, I query item_names to see if this name already exists. If not, I create a new entry. When deleting an item, I count the number of entries with the same name. If this is the only item with that name, I delete the entry from the item_names table (just to keep things clean; accounts for possible erroneous submissions). And updating is the combination of both. Weird Item Names: Store owners sometimes use sentences like "Harry Potter 1, 2 Books + CDs + Magic Hat". There's something off about having so much overhead to accommodate cases like this. This would perhaps be the prime reason I'm tempted to go for a schema like this: items: id | name | picture | price | description | picture (... with item_names and item_synonyms as utility tables that I could query) Is there a better schema you would suggested? Should item names be normalized for autocomplete? Is this probably what Facebook does for "School", "City" entries? Is the first schema or the second better/optimal for search? Thanks in advance! References: (1) Is normalizing a person's name going too far?, (2) Avoiding DISTINCT

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