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  • SQLiteException and SQLite error near "(": syntax error with Subsonic ActiveRecord

    - by nvuono
    I ran into an interesting error with the following LiNQ query using LiNQPad and when using Subsonic 3.0.x w/ActiveRecord within my project and wanted to share the error and resolution for anyone else who runs into it. The linq statement below is meant to group entries in the tblSystemsValues collection into their appropriate system and then extract the system with the highest ID. from ksf in KeySafetyFunction where ksf.Unit == 2 && ksf.Condition_ID == 1 join sys in tblSystems on ksf.ID equals sys.KeySafetyFunction join xval in (from t in tblSystemsValues group t by t.tblSystems_ID into groupedT select new { sysId = groupedT.Key, MaxID = groupedT.Max(g=>g.ID), MaxText = groupedT.First(gt2 => gt2.ID == groupedT.Max(g=>g.ID)).TextValue, MaxChecked = groupedT.First(gt2 => gt2.ID == groupedT.Max(g=>g.ID)).Checked }) on sys.ID equals xval.sysId select new {KSFDesc=ksf.Description, sys.Description, xval.MaxText, xval.MaxChecked} On its own, the subquery for grouping into groupedT works perfectly and the query to match up KeySafetyFunctions with their System in tblSystems also works perfectly on its own. However, when trying to run the completed query in linqpad or within my project I kept running into a SQLiteException SQLite Error Near "(" First I tried splitting the queries up within my project because I knew that I could just run a foreach loop over the results if necessary. However, I continued to receive the same exception! I eventually separated the query into three separate parts before I realized that it was the lazy execution of the queries that was killing me. It then became clear that adding the .ToList() specifier after the myProtectedSystem query below was the key to avoiding the lazy execution after combining and optimizing the query and being able to get my results despite the problems I encountered with the SQLite driver. // determine the max Text/Checked values for each system in tblSystemsValue var myProtectedValue = from t in tblSystemsValue.All() group t by t.tblSystems_ID into groupedT select new { sysId = groupedT.Key, MaxID = groupedT.Max(g => g.ID), MaxText = groupedT.First(gt2 => gt2.ID ==groupedT.Max(g => g.ID)).TextValue, MaxChecked = groupedT.First(gt2 => gt2.ID ==groupedT.Max(g => g.ID)).Checked}; // get the system description information and filter by Unit/Condition ID var myProtectedSystem = (from ksf in KeySafetyFunction.All() where ksf.Unit == 2 && ksf.Condition_ID == 1 join sys in tblSystem.All() on ksf.ID equals sys.KeySafetyFunction select new {KSFDesc = ksf.Description, sys.Description, sys.ID}).ToList(); // finally join everything together AFTER forcing execution with .ToList() var joined = from protectedSys in myProtectedSystem join protectedVal in myProtectedValue on protectedSys.ID equals protectedVal.sysId select new {protectedSys.KSFDesc, protectedSys.Description, protectedVal.MaxChecked, protectedVal.MaxText}; // print the gratifying debug results foreach(var protectedItem in joined) { System.Diagnostics.Debug.WriteLine(protectedItem.Description + ", " + protectedItem.KSFDesc + ", " + protectedItem.MaxText + ", " + protectedItem.MaxChecked); }

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  • How can I load a property lazily in JDO (on Google App Engine)?

    - by luciano
    I have this code in one of my @PersistenceCapable classes: @Persistent private Blob data; The Blob can be quite big, so I'd like to load it lazily since most of the times I don't need it. How can I annotate that property to avoid immediate loading? I could create another class that contains the Blob alone and then use a lazy one-to-one, but I'd like to solve this with annotations.

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  • Pros/Cons of switching from Exchange to GMail

    - by Brent
    We are a medium-large non-profit company, with around 1000 staff and volunteers, and have been using MS Exchange (currently 2003) for our mail system for years. I recently attended a Google conference where they were positing that "Cloud computing is the way of the future", and encouraging us to switch from doing our own email with Exchange, to using GMail and Google Apps for everything. Additionally, one of our departments has been pushing from inside to do this transition within their own department, if not throughout the entire organization. I can definitely see some benefits - such as: Archive space - we never seem to have the space our users want, and of course, the more we get, the more we have to back up OS Agnostic - Exchange is definitely built for windows, and with mac and linux users on the rise, these users increasingly demand better tools / support. Google offers this. Better archiving - potential of e-discovery, that doesn't exist in a practical way with our current setup. Switching would relieve us of a fair bit of server administration, give more options to our end users, and free up the server resources we are now using for Exchange. Our IT department wants to be perceived as providing up-to-date solutions to technical problems, and this change would definitely provide such an image. Google's infrastructure is obviously much more robust than ours, and they employ some of the world's best security and network experts. However, there are also some serious drawbacks: We would be essentially outsourcing one of our mission-critical systems to a 3rd party The switch would inevitably involve Google Apps and perhaps more as well. That means we would have a-lot more at the mercy of a single (potentially weak) password. (is there a way to make this more secure using a password plus physical key of some sort??) Our data would not remain under our roof - or even in our country (Canada). This obviously has plusses on the Disaster Recovery side, but I think there are potential negatives on the legal side. I can't imagine that somebody as large as Google would be as responsive as we would want with regard to non-critical issues such as tracing missing emails, etc. (not sure how much access we would have to basic mail logs - for instance) Can anyone help me evaluate this decision? What issues am I overlooking? What experiences have you had with this transition (or the opposite - gmail to Exchange) Can you add to the points I have already outlined?

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  • Flexible/variable/wildcard vhosts/hosts

    - by Moak
    I am using wamp, have all my projects in E:\webs\*projectname*\htdocs I want to access all of them in my browser with http://*projectname*.loc is there a way i can set up hosts and vhosts files so i never have to open them again? note this is for my own personal use, and I can change from .loc to .whatever if ICANN decides to start selling .loc domains.

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  • Flexible/variable vhosts/hosts

    - by Moak
    I am using wamp, have all my projects in E:\webs\*projectname*\htdocs I want to access all of them in my browser with http://*projectname*.loc is there a way i can set up hosts and vhosts files so i never have to open them again? note this is for my own personal use, and I can change from .loc to .whatever if ICANN decides to start selling .loc domains.

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  • A good file management/hosting/storage web service with embed-function?

    - by Andreas
    I am looking for a file management web service that lets me integrate the directory-view into a commercial website. Another requirement: User can register themselves, but need to be approved, before being able to download files. So something like box.net, but with more than just a a flash-widget. I would prefer some javascript, that can be embedded. Thanks for any recommendations.

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  • How does the ? make a quantifier lazy in regex

    - by Uriel Katz
    I've been looking into regex lately and figured that the ? operator makes the *,+, or ? lazy. My question is how does it do that? Is it that *? for example is a special operator, or does the ? have an effect on the *? In other words, does regex recognize *? as one operator in itself, or does regex recognize *? as the two separate operators * and ?? If it is the case that *? is being recognized as two separate operators, how does the ? affect the * to make it lazy. If ? means that the * is optional, shouldn't this mean that the * doesn't have to exists at all. If so, then in a statement .*? wouldn't regex just match separate letters and the whole string instead of the shorter string? Please explain, I'm desperate to understand.

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  • Perl, evaluate string lazily

    - by Mike
    Consider the following Perl code. #!/usr/bin/perl use strict; use warnings; $b="1"; my $a="${b}"; $b="2"; print $a; The script obviously outputs 1. I would like it to be whatever the current value of $b is. What would be the smartest way in Perl to achieve lazy evaluation like this? I would like the ${b} to remain "unreplaced" until $a is needed.

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  • SkyDrive : Microsoft fait une auto-évaluation de son service de stockage Cloud et souhaite renforcer celui-ci

    Skydrive : Microsoft fait une évaluation de son service de stockage Cloud et souhaite renforcer celui-ci SkyDrive, la solution de stockage des données en mode Cloud de Microsoft, bien qu'ayant subir plusieurs mises à jour et adopter le HTML5 pour son interface utilisateur, afin d'améliorer l'expérience d'accès et de partage des documents, présente encore des limites. Omar Shahine et Mike Torres, tous deux gestionnaires de programme pour Skydrive analysent dans un billet de blog l'univers des services Cloud en général, et Skydrive en particulier avec ses manquements et les futures améliorations qui seront apportées au service. Microsoft distingue tout d'abord trois types de...

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  • Implicit casting in VB.NET

    - by Shimmy
    The question is intended for lazy VB programmers. Please. In vb I can do and I won't get any errors. Example 1 Dim x As String = 5 Dim y As Integer = "5" Dim b As Boolean = "True" Example 2 Dim a As EnumType = 4 Dim v As Integer = EnumType.EnumValue Example 3 Private Sub ButtonClick(sender As Object, e As EventArgs) Dim btn As Button = sender End Sub Example 4 Private Sub ButtonClick(sender As Button, e As EventArgs) Dim data As Contact = sender.Tag End Sub If I surely know the expected runtime type, is this 'forbidden' to rely on the vb-language built-in casting? When can I rely? Thanks

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  • How to keep an Hibernate's Session open until the page is rendered

    - by Neuquino
    I'm having the following problem: I'm using Oracle ADF for the view and controller of my app. With OpenSessionInViewFilter, I intercept the request and open an Hibernate's Session, and it is closed as soon as the bean's method finishes. What I need is to keep the Session opened until the page is rendered, because in my JSP y use the lazy attributes of the object i load from the DB. For example: When I enter index.jspx the IndexBean#main() is executed: public class IndexBean{ private DBObject myDBObject; public String main(){ this.myDBObject = this.myDAO.loadObjectFromDB(); return null; } } in index.jspx I have: ... <af:inputText value="#{myDBObject.lazyAttribute}" /> ... I'd like that the Hibernate's Session keeps open until the af:inputText is processed. Is this possible? How? Thanks in advance

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  • Is it possible to match with decomposed sequences in F#?

    - by Ball
    I seem to remember an older version of F# allowing structural decomposition when matching sequences just like lists. Is there a way to use the list syntax while keeping the sequence lazy? I'm hoping to avoid a lot of calls to Seq.head and Seq.skip 1. I'm hoping for something like: let decomposable (xs:seq<'a>) = match xs with | h :: t -> true | _ -> false seq{ 1..100 } |> decomposable But this only handles lists and gives a type error when using sequences. When using List.of_seq, it seems to evaluate all the elements in the sequence, even if it is infinite.

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  • printing menu in terminal and choosing an option, how to?

    - by carlos
    I'm a haskell beginner. I'm trying to make a program that shows a menu through terminal and ask user to introduce an option. Here is the code: main :: IO () main = do putStrLn "0 <- quit" putStrLn "1 <- Hello" putStr "Choose an option: " c <- getChar case c of '0' -> return () '1' -> putChar '\n' >> putStrLn "Hello World" >> main When I use this module in the ghci interpreter everything works like it's suposed to do. But if i compile this with: ghc hello.hs and run it in the terminal, it doesn't display the line "Choose an option:" before ask for a char to be introduced. I think this may be caused because of haskell lazy nature and I don't know how to fix it. Any ideas?

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  • Haskell, list of natural number

    - by Hellnar
    Hello, I am an absolute newbie in Haskell yet trying to understand how it works. I want to write my own lazy list of integers such as [1,2,3,4,5...]. For list of ones I have written ones = 1 : ones and when tried, works fine: *Main> take 10 ones [1,1,1,1,1,1,1,1,1,1] How can I do the same for increasing integers ? I have tried this but it indeed fails: int = 1 : head[ int + 1] And after that how can I make a method that multiplies two streams? such as: mulstream s1 s2 = head[s1] * head[s2] : mulstream [tail s1] [tail s2]

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  • Hibernate/Spring: failed to lazily initialize - no session or session was closed

    - by Niko
    I know something similar has been asked already, but unfortunately I wasn't able to find a reliable answer - even with searching for over 2 days. The basic problem is the same as asked multiple time. I have a simple program with two POJOs Event and User - where a user can have multiple events. @Entity @Table public class Event { private Long id; private String name; private User user; @Column @Id @GeneratedValue public Long getId() {return id;} public void setId(Long id) { this.id = id; } @Column public String getName() {return name;} public void setName(String name) {this.name = name;} @ManyToOne @JoinColumn(name="user_id") public User getUser() {return user;} public void setUser(User user) {this.user = user;} } @Entity @Table public class User { private Long id; private String name; private List events; @Column @Id @GeneratedValue public Long getId() { return id; } public void setId(Long id) { this.id = id; } @Column public String getName() { return name; } public void setName(String name) { this.name = name; } @OneToMany(mappedBy="user", fetch=FetchType.LAZY) public List getEvents() { return events; } public void setEvents(List events) { this.events = events; } } Note: This is a sample project. I really want to use Lazy fetching here. I use spring and hibernate and have a simple basic-db.xml for loading: <?xml version="1.0" encoding="UTF-8"? <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd" <bean id="myDataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close" scope="thread" <property name="driverClassName" value="com.mysql.jdbc.Driver" / <property name="url" value="jdbc:mysql://192.168.1.34:3306/hibernateTest" / <property name="username" value="root" / <property name="password" value="" / <aop:scoped-proxy/ </bean <bean class="org.springframework.beans.factory.config.CustomScopeConfigurer" <property name="scopes" <map <entry key="thread" <bean class="org.springframework.context.support.SimpleThreadScope" / </entry </map </property </bean <bean id="mySessionFactory" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean" scope="thread" <property name="dataSource" ref="myDataSource" / <property name="annotatedClasses" <list <valuedata.model.User</value <valuedata.model.Event</value </list </property <property name="hibernateProperties" <props <prop key="hibernate.dialect"org.hibernate.dialect.MySQLDialect</prop <prop key="hibernate.show_sql"true</prop <prop key="hibernate.hbm2ddl.auto"create</prop </props </property <aop:scoped-proxy/ </bean <bean id="myUserDAO" class="data.dao.impl.UserDaoImpl" <property name="sessionFactory" ref="mySessionFactory" / </bean <bean id="myEventDAO" class="data.dao.impl.EventDaoImpl" <property name="sessionFactory" ref="mySessionFactory" / </bean </beans Note: I played around with the CustomScopeConfigurer and SimpleThreadScope, but that didnt change anything. I have a simple dao-impl (only pasting the userDao - the EventDao is pretty much the same - except with out the "listWith" function: public class UserDaoImpl implements UserDao{ private HibernateTemplate hibernateTemplate; public void setSessionFactory(SessionFactory sessionFactory) { this.hibernateTemplate = new HibernateTemplate(sessionFactory); } @SuppressWarnings("unchecked") @Override public List listUser() { return hibernateTemplate.find("from User"); } @Override public void saveUser(User user) { hibernateTemplate.saveOrUpdate(user); } @Override public List listUserWithEvent() { List users = hibernateTemplate.find("from User"); for (User user : users) { System.out.println("LIST : " + user.getName() + ":"); user.getEvents().size(); } return users; } } I am getting the org.hibernate.LazyInitializationException - failed to lazily initialize a collection of role: data.model.User.events, no session or session was closed at the line with user.getEvents().size(); And last but not least here is the Test class I use: public class HibernateTest { public static void main(String[] args) { ClassPathXmlApplicationContext ac = new ClassPathXmlApplicationContext("basic-db.xml"); UserDao udao = (UserDao) ac.getBean("myUserDAO"); EventDao edao = (EventDao) ac.getBean("myEventDAO"); System.out.println("New user..."); User user = new User(); user.setName("test"); Event event1 = new Event(); event1.setName("Birthday1"); event1.setUser(user); Event event2 = new Event(); event2.setName("Birthday2"); event2.setUser(user); udao.saveUser(user); edao.saveEvent(event1); edao.saveEvent(event2); List users = udao.listUserWithEvent(); System.out.println("Events for users"); for (User u : users) { System.out.println(u.getId() + ":" + u.getName() + " --"); for (Event e : u.getEvents()) { System.out.println("\t" + e.getId() + ":" + e.getName()); } } ((ConfigurableApplicationContext)ac).close(); } } and here is the Exception I get: 1621 [main] ERROR org.hibernate.LazyInitializationException - failed to lazily initialize a collection of role: data.model.User.events, no session or session was closed org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: data.model.User.events, no session or session was closed at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:380) at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationExceptionIfNotConnected(AbstractPersistentCollection.java:372) at org.hibernate.collection.AbstractPersistentCollection.readSize(AbstractPersistentCollection.java:119) at org.hibernate.collection.PersistentBag.size(PersistentBag.java:248) at data.dao.impl.UserDaoImpl.listUserWithEvent(UserDaoImpl.java:38) at HibernateTest.main(HibernateTest.java:44) Exception in thread "main" org.hibernate.LazyInitializationException: failed to lazily initialize a collection of role: data.model.User.events, no session or session was closed at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationException(AbstractPersistentCollection.java:380) at org.hibernate.collection.AbstractPersistentCollection.throwLazyInitializationExceptionIfNotConnected(AbstractPersistentCollection.java:372) at org.hibernate.collection.AbstractPersistentCollection.readSize(AbstractPersistentCollection.java:119) at org.hibernate.collection.PersistentBag.size(PersistentBag.java:248) at data.dao.impl.UserDaoImpl.listUserWithEvent(UserDaoImpl.java:38) at HibernateTest.main(HibernateTest.java:44) Things I tried but did not work: assign a threadScope and using beanfactory (I used "request" or "thread" - no difference noticed): // scope stuff Scope threadScope = new SimpleThreadScope(); ConfigurableListableBeanFactory beanFactory = ac.getBeanFactory(); beanFactory.registerScope("request", threadScope); ac.refresh(); ... Setting up a transaction by getting the session object from the deo: ... Transaction tx = ((UserDaoImpl)udao).getSession().beginTransaction(); tx.begin(); users = udao.listUserWithEvent(); ... getting a transaction within the listUserWithEvent() public List listUserWithEvent() { SessionFactory sf = hibernateTemplate.getSessionFactory(); Session s = sf.openSession(); Transaction tx = s.beginTransaction(); tx.begin(); List users = hibernateTemplate.find("from User"); for (User user : users) { System.out.println("LIST : " + user.getName() + ":"); user.getEvents().size(); } tx.commit(); return users; } I am really out of ideas by now. Also, using the listUser or listEvent just work fine.

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  • Groovy as a substitute for Java when using BigDecimal?

    - by geejay
    I have just completed an evaluation of Java, Groovy and Scala. The factors I considered were: readability, precision The factors I would like to know: performance, ease of integration I needed a BigDecimal level of precision. Here are my results: Java void someOp() { BigDecimal del_theta_1 = toDec(6); BigDecimal del_theta_2 = toDec(2); BigDecimal del_theta_m = toDec(0); del_theta_m = abs(del_theta_1.subtract(del_theta_2)) .divide(log(del_theta_1.divide(del_theta_2))); } Groovy void someOp() { def del_theta_1 = 6.0 def del_theta_2 = 2.0 def del_theta_m = 0.0 del_theta_m = Math.abs(del_theta_1 - del_theta_2) / Math.log(del_theta_1 / del_theta_2); } Scala def other(){ var del_theta_1 = toDec(6); var del_theta_2 = toDec(2); var del_theta_m = toDec(0); del_theta_m = ( abs(del_theta_1 - del_theta_2) / log(del_theta_1 / del_theta_2) ) } Note that in Java and Scala I used static imports. Java: Pros: it is Java Cons: no operator overloading (lots o methods), barely readable/codeable Groovy: Pros: default BigDecimal means no visible typing, least surprising BigDecimal support for all operations (division included) Cons: another language to learn Scala: Pros: has operator overloading for BigDecimal Cons: some surprising behaviour with division (fixed with Decimal128), another language to learn

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  • Consecutive calls/evaulations in a form?

    - by Dave
    Hey guys, simple question... Working with XLISP to write a program, but I've seemed to run into a simple fundamental problem that I can't seem to work around: perhaps someone has a quick fix. I'm trying to write an if statement who's then-clause evaluates multiple forms and returns the value of the last. In example: (setq POSITION 'DINING-ROOM) (defun LOOK (DIRECTION ROOM) ... ) (defun SETPOS (ROOM) ... ) (defun WHERE () ... ) (defun MOVE (DIRECTION) (if (not(equal nil (LOOK DIRECTION POSITION))) ; If there is a room in that direction ( ; Then-block: Go to that room. Return where you are. (SETPOS (LOOK DIRECTION ROOM)) (WHERE) ) ( ; Else-block: Return error (list 'CANT 'GO 'THERE) ) ) The logical equivalent intended is: function Move (Direction) { if(Look(Direction, Room) != null) { SetPos(Look(Direction,Room)); return Where(); } else { return "Can't go there"; } } (Apologies for the poor web-formatting.) The problem I have is with: ( (SETPOS (LOOK DIRECTION ROOM)) (WHERE) ) I simply want to return the evaluation of WHERE, but I need to execute the SETPOS function first. XLISP doesn't like the extra parentheses: if I remove the outer set, my WHERE list becomes my else (I don't want that). If I remove the sets around SETPOS and WHERE, it treats WHERE like an argument for SETPOS; I also don't want that. So, how do I simply evaluate the first, then the second and then return the values of the last evaluated?

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  • Javascript Regex: Testing string for intelligent query

    - by Shyam
    Hi, I have a string that holds user input. This string can contain various types of data, like: a six digit id a zipcode that contains out of 4 digits and two alphanumeric characters a name (characters only) As I am using this string to search through a database, the query type is determined on the type of search, which i want to handle serverside using JavaScript (yes, I am using JavaScript serverside). Searching on StackOverflow, brought me some interesting information, like the .test-method, which seems perfect for my needs. The test-method returns either true or false based on the evaluation on the string using a regex object. I am using this page as a reference: http://www.javascriptkit.com/jsref/regexp.shtml So I am trying to determine the zipcode, by using the following very noobish regex. var r = /[A-Za-z]{2,2}/ As far I can understand, this should limit the amount of occurrences of alphanumeric characters to a maximum of two. See beneath the output of my JavaScript console. > var r = /[A-Za-z]{2,2}/ > var x = "2233AL" > r.test(x) true > var x = "2233A" > r.test(x) false > var x = "2233ALL" > r.test(x) true /* i want this to be false */ > A little help would be really appreciated!

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  • ASP.NET Lazy content loading thought WCF REST service.

    Using WCF REST services to implement dynatree plug-in of jQuery for Lazy loading of child nodes....Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • NHibernate correct way to reattach cached entity to different session

    - by Chris Marisic
    I'm using NHibernate to query a list of objects from my database. After I get the list of objects over them I iterate over the list of objects and apply a distance approximation algorithm to find the nearest object. I consider this function of getting the list of objects and apply the algorithm over them to be a heavy operation so I cache the object which I find from the algorithm in HttpRuntime.Cache. After this point whenever I'm given the supplied input again I can just directly pull the object from Cache instead of having to hit the database and traverse the list. My object is a complex object that has collections attached to it, inside the query where I return the full list of objects I don't bring back any of the sub collections eagerly so when I read my cached object I need lazy loading to work correctly to be able to display the object fully. Originally I tried using this to re-associate my cached object back to a new session _session.Lock(obj, LockMode.None); However when accessing the page concurrently from another instance I get the error Illegal attempt to associate a collection with two open sessions I then tried something different with _session.Merge(obj); However watching the output of this in NHProf shows that it is deleting and re-associating my object's contained collections with my object, which is not what I want although it seems to work fine. What is the correct way to do this? Neither of these seem to be right.

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  • Protecting sensitive entity data

    - by Andreas
    Hi, I'm looking for some advice on architecture for a client/server solution with some peculiarities. The client is a fairly thick one, leaving the server mostly to peristence, concurrency and infrastructure concerns. The server contains a number of entities which contain both sensitive and public information. Think for example that the entities are persons, assume that social security number and name are sensitive and age is publicly viewable. When starting the client, the user is presented with a number of entities, not disclosing any sensitive information. At any time the user can choose to log in and authenticate against the server, given the authentication is successful the user is granted access to the sensitive information. The client is hosting a domain model and I was thinking of implementing this as some kind of "lazy loading", making the first request instantiating the entities and later refreshing them with sensitive data. The entity getters would throw exceptions on sensitive information when they've not been disclosed, f.e.: class PersonImpl : PersonEntity { private bool undisclosed; public override string SocialSecurityNumber { get { if (undisclosed) throw new UndisclosedDataException(); return base.SocialSecurityNumber; } } } Another more friendly approach could be to have a value object indicating that the value is undisclosed. get { if (undisclosed) return undisclosedValue; return base.SocialSecurityNumber; } Some concerns: What if the user logs in and then out, the sensitive data has been loaded but must be disclosed once again. One could argue that this type of functionality belongs within the domain and not some infrastructural implementation(i.e. repository implementations). As always when dealing with a larger number of properties there's a risk that this type of functionality clutters the code Any insights or discussion is appreciated!

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  • NHibernate. Initiate save collection at saving parent

    - by Andrew Kalashnikov
    Hello, colleagues. I've got a problem at saving my entity. MApping: ?xml version="1.0" encoding="utf-8" ?> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" assembly="Clients.Core" namespace="Clients.Core.Domains"> <class name="Sales, Clients.Core" table='sales'> <id name="Id" unsaved-value="0"> <column name="id" not-null="true"/> <generator class="native"/> </id> <property name="Guid"> <column name="guid"/> </property> <set name="Accounts" table="sales_users" lazy="false"> <key column="sales_id" /> <element column="user_id" type="Int32" /> </set> Domain: public class Sales : BaseDomain { ICollection<int> accounts = new List<int>(); public virtual ICollection<int> Accounts { get { return accounts; } set { accounts = value; } } public Sales() { } } When I save Sales object Account collection don't save at sales_users table. What should I do for saving it? Please don't advice me use classes inside List Thanks a lot.

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  • Best Functional Approach

    - by dbyrne
    I have some mutable scala code that I am trying to rewrite in a more functional style. It is a fairly intricate piece of code, so I am trying to refactor it in pieces. My first thought was this: def iterate(count:Int,d:MyComplexType) = { //Generate next value n //Process n causing some side effects return iterate(count - 1, n) } This didn't seem functional at all to me, since I still have side effects mixed throughout my code. My second thought was this: def generateStream(d:MyComplexType):Stream[MyComplexType] = { //Generate next value n return Stream.cons(n, generateStream(n)) } for (n <- generateStream(initialValue).take(2000000)) { //process n causing some side effects } This seemed like a better solution to me, because at least I've isolated my functional value-generation code from the mutable value-processing code. However, this is much less memory efficient because I am generating a large list that I don't really need to store. This leaves me with 3 choices: Write a tail-recursive function, bite the bullet and refactor the value-processing code Use a lazy list. This is not a memory sensitive app (although it is performance sensitive) Come up with a new approach. I guess what I really want is a lazily evaluated sequence where I can discard the values after I've processed them. Any suggestions?

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