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• ASP.NET MVC RememberMe(It's large, please don't quit reading. Have explained the problem in detail a

  - by nccsbim071

  After searching a lot i did not get any answers and finally i had to get back to you. Below i am explaining my problem in detail. It's too long, so please don't quit reading. I have explained my problem in simple language. I have been developing an asp.net mvc project. I am using standard ASP.NET roles and membership. Everything is working fine but the remember me functionality doesn't work at all. I am listing all the details of work. Hope you guys can help me out solve this problem. I simply need this: I need user to login to web application. During login they can either login with remember me or without it. If user logs in with remember me, i want browser to remember them for long time, let's say atleast one year or considerably long time. The way they do it in www.dotnetspider.com,www.codeproject.com,www.daniweb.com and many other sites. If user logs in without remember me, then browser should allow access to website for some 20 -30 minutes and after that their session should expire. Their session should also expire when user logs in and shuts down the browser without logging out. Note: I have succesfully implemented above functionality without using standard asp.net roles and membership by creating my own talbes for user and authenticating against my database table, setting cookie and sessions in my other projects. But for this project we starting from the beginning used standard asp.net roles and membership. We thought it will work and after everything was build at the time of testing it just didn't work. and now we cannot replace the existing functionality with standard asp.net roles and membership with my own custom user tables and all the stuff, you understand what i am taling about. Either there is some kind of bug with standard asp.net roles and membership functionality or i have the whole concept of standard asp.net roles and membership wrong. i have stated what i want above. I think it's very simple and reasonable. What i did Login form with username,password and remember me field. My setting in web.config: <authentication mode="Forms"> <forms loginUrl="~/Account/LogOn" timeout="2880"/> </authentication> in My controller action, i have this: FormsAuth.SignIn(userName, rememberMe); public void SignIn(string userName, bool createPersistentCookie) { FormsAuthentication.SetAuthCookie(userName, createPersistentCookie); } Now the problems are following: I have already stated in above section "I simply need this". user can successfully log in to the system. Their session exists for as much minutes as specified in timeout value in web.config. I have also given a sample of my web.config. In my samplem if i set the timeout to 5 minutes,then user session expires after 5 minutes, that's ok. But if user closes the browser and reopen the browser, user can still enter the website without loggin in untill time specified in "timeout" has not passed out. The sliding expiration for timeout value is also working fine. Now if user logs in to the system with remember me checked, user session still expires after 5 minutes. This is not good behaviour, is it?. I mean to say that if user logs in to the system with remember me checked he should be remembered for a long time untill he doesn't logs out of the system or user doesn't manually deletes all the cookies from the browser. If user logs in to the system without remember me checked his session should expire after the timeout period values specified in web.config and also if users closes the browser. The problem is that if user closes the browser and reopens it he can still enter the website without logging in. I search internet a lot on this topic, but i could not get the solution. In the blog post(http://weblogs.asp.net/scottgu/archive/2005/11/08/430011.aspx) made by Scott Gu on exactly the same topic. The users are complaining about the same thing in their comments ut there is no easy solution given in by Mr. Scott. I read it at following places: http://weblogs.asp.net/scottgu/archive/2005/11/08/430011.aspx http://geekswithblogs.net/vivek/archive/2006/09/14/91191.aspx I guess this is a problem of lot's of users. As seem from blog post made by Mr. Scott Gu. Your help will be really appreciated. Thanks in advance.

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• Are Large iPhone Ping Times Indicative of Application Latency?

  - by yar

  I am contemplating creating a realtime app where an iPod Touch/iPhone/iPad talks to a server-side component (which produces MIDI, and sends it onward within the host). When I ping my iPod Touch on Wifi I get huge latency (and a enormous variance, too): 64 bytes from 192.168.1.3: icmp_seq=9 ttl=64 time=38.616 ms 64 bytes from 192.168.1.3: icmp_seq=10 ttl=64 time=61.795 ms 64 bytes from 192.168.1.3: icmp_seq=11 ttl=64 time=85.162 ms 64 bytes from 192.168.1.3: icmp_seq=12 ttl=64 time=109.956 ms 64 bytes from 192.168.1.3: icmp_seq=13 ttl=64 time=31.452 ms 64 bytes from 192.168.1.3: icmp_seq=14 ttl=64 time=55.187 ms 64 bytes from 192.168.1.3: icmp_seq=15 ttl=64 time=78.531 ms 64 bytes from 192.168.1.3: icmp_seq=16 ttl=64 time=102.342 ms 64 bytes from 192.168.1.3: icmp_seq=17 ttl=64 time=25.249 ms Even if this is double what the iPhone-Host or Host-iPhone time would be, 15ms+ is too long for the app I'm considering. Is there any faster way around this (e.g., USB cable)? If not, would building the app on Android offer any other options? Traceroute reports more workable times: traceroute to 192.168.1.3 (192.168.1.3), 64 hops max, 52 byte packets 1 192.168.1.3 (192.168.1.3) 4.662 ms 3.182 ms 3.034 ms can anyone decipher this difference between ping and traceroute for me, and what they might mean for an application that needs to talk to (and from) a host?

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• How can the DataView object reference not be set?

  - by dboarman-FissureStudios

  I have the following sample where the SourceData class would represent a DataView resulting from an Sql query: class MainClass { private static SourceData Source; private static DataView View; private static DataView Destination; public static void Main (string[] args) { Source = new SourceData(); View = new DataView(Source.Table); Destination = new DataView(); Source.AddRowData("Table1", 100); Source.AddRowData("Table2", 1500); Source.AddRowData("Table3", 1300324); Source.AddRowData("Table4", 1122494); Source.AddRowData("Table5", 132545); Console.WriteLine(String.Format("Data View Records: {0}", View.Count)); foreach(DataRowView drvRow in View) { Console.WriteLine(String.Format("Source {0} has {1} records.", drvRow["table"], drvRow["records"])); DataRowView newRow = Destination.AddNew(); newRow["table"] = drvRow["table"]; newRow["records"] = drvRow["records"]; } Console.WriteLine(); Console.WriteLine(String.Format("Destination View Records: {0}", Destination.Count)); foreach(DataRowView drvRow in Destination) { Console.WriteLine(String.Format("Destination {0} has {1} records.", drvRow["table"], drvRow["records"])); } } } class SourceData { public DataTable Table { get{return dataTable;} } private DataTable dataTable; public SourceData() { dataTable = new DataTable("TestTable"); dataTable.Columns.Add("table", typeof(string)); dataTable.Columns.Add("records", typeof(int)); } public void AddRowData(string tableName, int tableRows) { dataTable.Rows.Add(tableName, tableRows); } } My output is: Data View Records: 5 Source Table1 has 100 records. Unhandled Exception: System.NullReferenceException: Object reference not set to an instance of an object at System.Data.DataView.AddNew () [0x0003e] in /usr/src/packages/BUILD/mono-2.4.2.3 /mcs/class/System.Data/System.Data/DataView.cs:344 at DataViewTest.MainClass.Main (System.String[] args) [0x000e8] in /home/david/Projects/DataViewTest/SourceData.cs:29 I did some reading here: DataView:AddNew Method... ...and it would appear that I am doing this the right way. How come I am getting the Object reference not set?

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• Why eGet() in EMF returns Object rather than EObject?

  - by Gabriel Šcerbák

  I am working on some code using the EMF framework in Java, but it is really hard to use, e.g. I cannot implement OCL-like query API on top of EMF which would be type-safe. One of the reasons is that eGet() for a EStructuralFeature return just an Object, not EObject. So anything I would write must use much of null checking, type checking and type casting which is unsafe, not performant and cannot be generalized in a reusable way. Why doesn't EMF generate dummy implementations with EObject wrappers for arbitrary Object value? Implementing the EObject and hence the EClass interfaces even with simple throw UnsupportedOperationException is really a pain (the APIs are too big). The same holds for the eContainer() method which makes navigatinng the model upwards painful.

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• Can you find a pattern to sync files knowing only dates and filenames?

  - by Robert MacLean

  Imagine if you will a operating system that had the following methods for files Create File: Creates (writes) a new file to disk. Calling this if a file exists causes a fault. Update File: Updates an existing file. Call this if a file doesn't exist causes a fault. Read File: Reads data from a file. Enumerate files: Gets all files in a folder. Files themselves in this operating system only have the following meta data: Created Time: The original date and time the file was created, by the Create File method. Modified Time: The date and time the file was last modified by the Update File method. If the file has never been modified, this will equal the Create Time. You have been given the task of writing an application which will sync the files between two directories (lets call them bill and ted) on a machine. However it is not that simple, the client has required that The application never faults (see methods above). That while the application is running the users can add and update files and those will be sync'd next time the application runs. Files can be added to either the ted or bill directories. File names cannot be altered. The application will perform one sync per time it is run. The application must be almost entirely in memory, in other words you cannot create a log of filenames and write that to disk and then check that the next time. The exception to point 6 is that you can store date and times between runs. Each date/time is associated with a key labeled A through J (so you have 10 to use) so you can compare keys between runs. There is no way to catch exceptions in the application. Answer will be accepted based on the following conditions: First answer to meet all requirements will be accepted. If there is no way to meet all requirements, the answer which ensures the smallest amount of missed changes per sync will be accepted. A bounty will be created (100 points) as soon as possible for the prize. The winner will be selected one day before the bounty ends. Please ask questions in the comments and I will gladly update and refine the question on those.

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• Dynamic Linq help, different errors depending on object passed as parameter?

  - by sah302

  I have an entityDao that is inherbited by everyone of my objectDaos. I am using Dynamic Linq and trying to get some generic queries to work. I have the following code in my generic method in my EntityDao : public abstract class EntityDao<ImplementationType> where ImplementationType : Entity { public ImplementationType getOneByValueOfProperty(string getProperty, object getValue){ ImplementationType entity = null; if (getProperty != null && getValue != null) { LCFDataContext lcfdatacontext = new LCFDataContext(); //Generic LINQ Query Here entity = lcfdatacontext.GetTable<ImplementationType>().Where(getProperty + " =@0", getValue).FirstOrDefault(); //.Where(getProperty & "==" & CStr(getValue)) } //lcfdatacontext.SubmitChanges() //lcfdatacontext.Dispose() return entity; } }         Then I do the following method call in a unit test (all my objectDaos inherit entityDao): [Test] public void getOneByValueOfProperty() { Accomplishment result = accomplishmentDao.getOneByValueOfProperty("AccomplishmentType.Name", "Publication"); Assert.IsNotNull(result); } The above passes (AccomplishmentType has a relationship to accomplishment) Accomplishment result = accomplishmentDao.getOneByValueOfProperty("Description", "Can you hear me now?"); Accomplishment result = accomplishmentDao.getOneByValueOfProperty("LocalId", 4); Both of the above work Accomplishment result = accomplishmentDao.getOneByValueOfProperty("Id", New Guid("95457751-97d9-44b5-8f80-59fc2d170a4c"))       Does not work and says the following: Operator '=' incompatible with operand types 'Guid' and 'Guid Why is this happening? Guid's can't be compared? I tried == as well but same error. What's even moreso confusing is that every example of Dynamic Linq I have seen simply usings strings whether using the parameterized where predicate or this one I have commented out: //.Where(getProperty & "==" & CStr(getValue)) With or without the Cstr, many datatypes don't work with this format. I tried setting the getValue to a string instead of an object as well, but then I just get different errors (such as a multiword string would stop comparison after the first word). What am I missing to make this work with GUIDs and/or any data type? Ideally I would like to be able to just pass in a string for getValue (as I have seen for every other dynamic LINQ example) instead of the object and have it work regardless of the data Type of the column.

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• ASP.NET RememberMe(It's large, please don't quit reading. Have explained the problem in detail and s

  - by nccsbim071

  After searching a lot i did not get any answers and finally i had to get back to you. Below i am explaining my problem in detail. It's too long, so please don't quit reading. I have explained my problem in simple language. I have been developing an asp.net mvc project. I am using standard ASP.NET roles and membership. Everything is working fine but the remember me functionality doesn't work at all. I am listing all the details of work. Hope you guys can help me out solve this problem. I simply need this: I need user to login to web application. During login they can either login with remember me or without it. If user logs in with remember me, i want browser to remember them for long time, let's say atleast one year or considerably long time. The way they do it in www.dotnetspider.com,www.codeproject.com,www.daniweb.com and many other sites. If user logs in without remember me, then browser should allow access to website for some 20 -30 minutes and after that their session should expire. Their session should also expire when user logs in and shuts down the browser without logging out. Note: I have succesfully implemented above functionality without using standard asp.net roles and membership by creating my own talbes for user and authenticating against my database table, setting cookie and sessions in my other projects. But for this project we starting from the beginning used standard asp.net roles and membership. We thought it will work and after everything was build at the time of testing it just didn't work. and now we cannot replace the existing functionality with standard asp.net roles and membership with my own custom user tables and all the stuff, you understand what i am taling about. Either there is some kind of bug with standard asp.net roles and membership functionality or i have the whole concept of standard asp.net roles and membership wrong. i have stated what i want above. I think it's very simple and reasonable. What i did Login form with username,password and remember me field. My setting in web.config: in My controller action, i have this: FormsAuth.SignIn(userName, rememberMe); public void SignIn(string userName, bool createPersistentCookie) { FormsAuthentication.SetAuthCookie(userName, createPersistentCookie); } Now the problems are following: I have already stated in above section "I simply need this". user can successfully log in to the system. Their session exists for as much minutes as specified in timeout value in web.config. I have also given a sample of my web.config. In my samplem if i set the timeout to 5 minutes,then user session expires after 5 minutes, that's ok. But if user closes the browser and reopen the browser, user can still enter the website without loggin in untill time specified in "timeout" has not passed out. The sliding expiration for timeout value is also working fine. Now if user logs in to the system with remember me checked, user session still expires after 5 minutes. This is not good behaviour, is it?. I mean to say that if user logs in to the system with remember me checked he should be remembered for a long time untill he doesn't logs out of the system or user doesn't manually deletes all the cookies from the browser. If user logs in to the system without remember me checked his session should expire after the timeout period values specified in web.config and also if users closes the browser. The problem is that if user closes the browser and reopens it he can still enter the website without logging in. I search internet a lot on this topic, but i could not get the solution. In the blog post(http://weblogs.asp.net/scottgu/archive/2005/11/08/430011.aspx) made by Scott Gu on exactly the same topic. The users are complaining about the same thing in their comments ut there is no easy solution given in by Mr. Scott. I read it at following places: http://weblogs.asp.net/scottgu/archive/2005/11/08/430011.aspx http://geekswithblogs.net/vivek/archive/2006/09/14/91191.aspx I guess this is a problem of lot's of users. As seem from blog post made by Mr. Scott Gu. Your help will be really appreciated. Thanks in advance.

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• Is it possible to connect slots of a model object to the GUI in QT4 -Designer?

  - by Robert0

  So I try to build a Model-View window using QTDesigner and C++. For that reason I created a QOBject derived class as my model. It provides slots and signals to access it like: setFileName(QString) or fileNameChanged(QString). I got a little into using signal drag and drop in QTDesigner and found it quite VA-Smalltalk-Like nice. After a while I was wondering if I could also connect my model to this. So is it possible to somehow introduce my model object into the Window/GUI and let QTDesigner connect signals and slots from the model object to the GUI. In essence: Write for me: connect( model, SIGNAL(fileNameChanged(QString)), ui->labelFn, SLOT(setText(QString))) connect( ui-textEdit2, SIGNAL(textChanged(QString)), model, SLOT(setFileName(QString))) Thanks for explaining

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• iPhone plist data, large amounts of text and return key?

  - by user278342

  Basicly iv built my app using a plist. But with the data there is a few times when I need to press return and start a new line. The return key doesn't work in the plist. If I did it the older way it would be \n\n but that doesn't work either. Is there a obvious way I'm overlooking? Or will it be a case off just pressing the space bar allot? Thanks

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• Can Automapper populate a strongly typed object from the data in a NameValueCollection?

  - by Seth Petry-Johnson

  Can Automapper map values from a NameValueCollection onto an object, where target.Foo receives the value stored in the collection under the "Foo" key? I have a business object that stores some data in named properties and other data in a property bag. Different views make different assumptions about the data in the property bag, which I capture in page-specific view models. I want to use AutoMapper to map both the "inherent" attributes (the ones that always exist) as well as the "dynamic" attributes (the ones that vary per view and may or may not exist).

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• Why would this div have an unnecessarily large computed height?

  - by Mike Crittenden

  Link: http://www.fraynepainting.com/services The problem is that div#dditem_2 (the div with the "Take a look..." text) is getting a computed height of around 500px for no reason that I can find in the CSS, which is pushing the UL below it down really really far. I discovered that if you set display: none or position: absolute (or anything else that removes it from the flow of elements) on the sidebar, then the bottom UL moves up like it should, so it looks like maybe the UL is trying to clear the sidebar, but I can't figure out why that would be either. I've reproduced the problem in Firefox and Chrome so far. Any ideas?

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• Why is there a large difference in quality between the C# and JavaScript specifications?

  - by ChaosPandion

  I have been studying the JavaScript standard and have found that it is extremely hard to read and understand. I constantly have to backtrack to keep concepts in my head. When reading the C# standard I am able to study components of the language without constantly moving around the document. JavaScript Specification C# Specification

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• How can I efficiently group a large list of URLs by their host name in Perl?

  - by jesper

  I have text file that contains over one million URLs. I have to process this file in order to assign URLs to groups, based on host address: { 'http://www.ex1.com' = ['http://www.ex1.com/...', 'http://www.ex1.com/...', ...], 'http://www.ex2.com' = ['http://www.ex2.com/...', 'http://www.ex2.com/...', ...] } My current basic solution takes about 600 MB of RAM to do this (size of file is about 300 MB). Could you provide some more efficient ways? My current solution simply reads line by line, extracts host address by regex and puts the url into a hash. EDIT Here is my implementation (I've cut off irrelevant things): while($line = <STDIN>) { chomp($line); $line =~ /(http:\/\/.+?)(\/|$)/i; $host = "$1"; push @{$urls{$host}}, $line; } store \%urls, 'out.hash';

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• what is Regex pattern for html tag in java or android ?

  - by androidbase

  i have this tag as input tag: <a href="controller.jsp?sid=127490C88DB5&R=35144" class="11-link-dkred-bold"><b>Mr. John Q. Anderson&nbsp;&nbsp;&nbsp;MBA 1977 E</a> in this i want get the value Mr. John Q. Anderson   MBA 1977 E wat is patten value for this in regex?

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• What is the equivalent to Java's canvas object in C#?

  - by Winston

  I'm working on creating a basic application that will let a user draw (using a series of points) and I plan to do something with these points. If this were Java, I think I would probably use a canvas object and some Java2D calls to draw what I want. All the tutorials I've read on C#/Drawing involve writing your own paint method and adding it to the paint event for the form. However, I'm interested in having some traditional Form controls as well and I don't want to be drawing over them. So, is there a "Canvas" object where I can constrain what I'm drawing on? Also, is WinForms a poor choice given this use case? Would WPF have more features that would help enable me to do what I want? Or Silverlight?

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• Can you drag and drop a URL with a large icon/graphic from a web page to you desktop?

  - by Peter Mahnke

  Is there anyway to create a desktop icon (cross platform/browser) from a linked image on a page without some kind of executable? <a href="http://www.example.com"><img src="nice_icon.png" /></a>

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• How to handle optional variables of an object in Java?

  - by Arvanem

  Hi folks, For my trading program, I have a Merchant class. A given Merchant object may or may not have a particular special quality or bundle of special qualities. For example, one Merchant object may have the Stockbroker quality, another Merchant may have the Financial Services and Stockbroker qualities, and another Merchant may have no special qualities at all. My initial thought was to create a HashMap and a Qualities class as follows: Map<Qualities, Boolean> merchantQualities = new HashMap<Qualities, Boolean>(); The only problem is, there are at least 50 possible special qualities for Merchants, such that it would be extremely tiresome to subclass all the qualities from the Quality class. Is there a better way of coding for these optional special qualities and representing them in the Merchants class than a HashMap and subclassing a Qualities class?

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• Optimal method to create a large string containing several variables?

  - by Runcible

  I want to create a string that contains many variables: std::string name1 = "Frank"; std::string name2 = "Joe"; std::string name3 = "Nancy"; std::string name4 = "Sherlock"; std::string sentence; sentence = name1 + " and " + name2 + " sat down with " + name3; sentence += " to play cards, while " + name4 + " played the violin."; This should produce a sentence that reads Frank and Joe sat down with Nancy to play cards, while Sherlock played the violin. My question is: What is the optimal way to accomplish this? I am concerned that constantly using the + operator is ineffecient. Is there a better way?

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• Why doesn't DomainContext from WCF RIA Services implement the IDisposable pattern ?

  - by Scott Davies

  Hi, Just doing some work with RIA services and I see in the MSDN documentation that neither it or any parents up its' hierarchy implement IDisposable. I'm wondering what the design decision was for this...as DomainContext is a stateful resource, wouldn't it be nice to have a Dispose() to release it when done ? Thanks, Scott

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• Is there a better way to create an object-oriented class with jquery?

  - by Devon

  I use the jquery extend function to extend a class prototype. For example: MyWidget = function(name_var) { this.init(name_var); } $.extend(MyWidget.prototype, { // object variables widget_name: '', init: function(widget_name) { // do initialization here this.widget_name = widget_name; }, doSomething: function() { // an example object method alert('my name is '+this.widget_name); } }); // example of using the class built above var widget1 = new MyWidget('widget one'); widget1.doSomething(); Is there a better way to do this? Is there a cleaner way to create the class above with only one statement instead of two?

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• How to convert an arbitrary object to String with JSTL? (calling toString())

  - by hstoerr

  Is there any way to call toString() on an object with the JSTL? (I need the String representation of an enum as index in a map in a JSP EL expression.) I hoped something like ${''+object} would work like in java, but JSTL isn't that nice, and there does not seem to be any function that does it. Clarification: I have a variable somemap that maps Strings to Strings, and I have a variable someenum that is an enumeration. I'd like to do something like ${somemap[someenum.toString()]}. (Of course .toString() does not work, but what does?)

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• How could I read a very large text file using StreamReader?

  - by Sergio Tapia

  I want to read a huge .txt file and I'm getting a memory overflow because of its sheer size. Any help?

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• Why is there a large difference in readability between the C# and JavaScript specifications?

  - by ChaosPandion

  I have been studying the JavaScript standard and have found that it is extremely hard to read and understand. I constantly have to backtrack to keep concepts in my head. When reading the C# standard I am able to study components of the language without constantly moving around the document. JavaScript Specification C# Specification

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• Changing property type in class that implements interface with object type property.

  - by used2could

  I know the title is a bit confusing but bare with me. (I'm up for suggestions on a new title lol) I'm writing a TemplateEngine that will allow me to use my own markup in text based files. I'm wanting to add controls as plugins as the application matures. Currently i've got a structure like the following: interface IControl string Id object Value class Label : IControl string Id string Value class Repeater : IControl string Id List<IControl> Value Now you'll see the strange part right away in the Repeater class with the Value property. I was hoping that having the Value type as object in the interface would allow me the flexibility to expand the controls as i go along. The compiler doesn't like this and for good reason i guess. Does anyone have any suggestions how to accomplish this? Note: Please don't go into suggesting things like use Spark View Engine for templating. There is a reason i'm creating extra work for myself.

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• Optimize date query for large child tables: GiST or GIN?

  - by Dave Jarvis

  Problem 72 child tables, each having a year index and a station index, are defined as follows: CREATE TABLE climate.measurement_12_013 ( -- Inherited from table climate.measurement_12_013: id bigint NOT NULL DEFAULT nextval('climate.measurement_id_seq'::regclass), -- Inherited from table climate.measurement_12_013: station_id integer NOT NULL, -- Inherited from table climate.measurement_12_013: taken date NOT NULL, -- Inherited from table climate.measurement_12_013: amount numeric(8,2) NOT NULL, -- Inherited from table climate.measurement_12_013: category_id smallint NOT NULL, -- Inherited from table climate.measurement_12_013: flag character varying(1) NOT NULL DEFAULT ' '::character varying, CONSTRAINT measurement_12_013_category_id_check CHECK (category_id = 7), CONSTRAINT measurement_12_013_taken_check CHECK (date_part('month'::text, taken)::integer = 12) ) INHERITS (climate.measurement) CREATE INDEX measurement_12_013_s_idx ON climate.measurement_12_013 USING btree (station_id); CREATE INDEX measurement_12_013_y_idx ON climate.measurement_12_013 USING btree (date_part('year'::text, taken)); (Foreign key constraints to be added later.) The following query runs abysmally slow due to a full table scan: SELECT count(1) AS measurements, avg(m.amount) AS amount FROM climate.measurement m WHERE m.station_id IN ( SELECT s.id FROM climate.station s, climate.city c WHERE -- For one city ... -- c.id = 5182 AND -- Where stations are within an elevation range ... -- s.elevation BETWEEN 0 AND 3000 AND 6371.009 * SQRT( POW(RADIANS(c.latitude_decimal - s.latitude_decimal), 2) + (COS(RADIANS(c.latitude_decimal + s.latitude_decimal) / 2) * POW(RADIANS(c.longitude_decimal - s.longitude_decimal), 2)) ) <= 50 ) AND -- -- Begin extracting the data from the database. -- -- The data before 1900 is shaky; insufficient after 2009. -- extract( YEAR FROM m.taken ) BETWEEN 1900 AND 2009 AND -- Whittled down by category ... -- m.category_id = 1 AND m.taken BETWEEN -- Start date. (extract( YEAR FROM m.taken )||'-01-01')::date AND -- End date. Calculated by checking to see if the end date wraps -- into the next year. If it does, then add 1 to the current year. -- (cast(extract( YEAR FROM m.taken ) + greatest( -1 * sign( (extract( YEAR FROM m.taken )||'-12-31')::date - (extract( YEAR FROM m.taken )||'-01-01')::date ), 0 ) AS text)||'-12-31')::date GROUP BY extract( YEAR FROM m.taken ) The sluggishness comes from this part of the query: m.taken BETWEEN /* Start date. */ (extract( YEAR FROM m.taken )||'-01-01')::date AND /* End date. Calculated by checking to see if the end date wraps into the next year. If it does, then add 1 to the current year. */ (cast(extract( YEAR FROM m.taken ) + greatest( -1 * sign( (extract( YEAR FROM m.taken )||'-12-31')::date - (extract( YEAR FROM m.taken )||'-01-01')::date ), 0 ) AS text)||'-12-31')::date The HashAggregate from the plan shows a cost of 10006220141.11, which is, I suspect, on the astronomically huge side. There is a full table scan on the measurement table (itself having neither data nor indexes) being performed. The table aggregates 237 million rows from its child tables. Question What is the proper way to index the dates to avoid full table scans? Options I have considered: GIN GiST Rewrite the WHERE clause Separate year_taken, month_taken, and day_taken columns to the tables What are your thoughts? Thank you!

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