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• Database Design and Performance : mySQL and PHP

  - by jasmine

  I have made an image for this question: What is the right design? All site's block inserting in only one table or separate tables? Thanks in advance

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• AJAX driven "page complete" function? Am I doing it right?

  - by Julian H. Lam

  This one might get me slaughtered, since I'm pretty sure it's bad coding practice, so here goes: I have an AJAX driven site which loads both content and javascript in one go using Mootools' Request.HTML. Since I have initialization scripts that need to be run to finish "setting up" the template, I include those in a function called pageComplete(), on every page Visiting one page to another causes the previous pageComplete() function to no longer apply, since a new one is defined. The javascript function that loads pages dynamically calls pageComplete() blindly when the AJAX call is completed and is loaded onto the page: function loadPage(page, params) { // page is a string, params is a javascript object if (pageRequest && pageRequest.isRunning) pageRequest.cancel(); pageRequest = new Request.HTML({ url: '<?=APPLICATION_LINK?>' + page, evalScripts: true, onSuccess: function(tree, elements, html) { // Empty previous content and insert new content $('content').empty(); $('content').innerHTML = html; pageComplete(); pageRequest = null; } }).send('params='+JSON.encode(params)); } So yes, if pageComplete() is not defined in one the pages, the old pageComplete() is called, which could potentially be disastrous, but as of now, every single page has pageComplete() defined, even if it is empty. Good idea, bad idea?

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• How do I develop database-utilizing application in an agile/test-driven-development way?

  - by user39019

  I want to add databases (traditional client/server RDBMS's like Mysql/Postgresql as opposed to NoSQL, or embedded databases) to my toolbox as a developer. I've been using SQLite for simpler projects with only 1 client, but now I want to do more complicated things (ie, db-backed web development). I usually like following agile and/or test-driven-development principles. I generally code in Perl or Python. Questions: How do I test my code such that each run of the test suite starts with a 'pristine' state? Do I run a separate instance of the database server every test? Do I use a temporary database? How do I design my tables/schema so that it is flexible with respect to changing requirements? Do I start with an ORM for my language? Or do I stick to manually coding SQL? One thing I don't find appealing is having to change more than one thing (say, the CREATE TABLE statement and associated crud statements) for one change, b/c that's error prone. On the other hand, I expect ORM's to be a low slower and harder to debug than raw SQL. What is the general strategy for migrating data between one version of the program and a newer one? Do I carefully write ALTER TABLE statements between each version, or do I dump the data and import fresh in the new version?

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• What is the right approach to use adsense with responsive web design?

  - by Sisir

  Recently I was studying responsive design a lot and designed couple of sites. But i was wondering how would I use google adsense (which is pixel based) ads on my responsive design? Very typical example is suppose I have a 728x90 ads on header. Or if i do a mobile first approach i would need different versions of ad sizes for different view posts but google doesn't allow more than three ad unit per page (as far as i know). So, Question: What is the right approach/best practice of using google adsense on a responsive site design?

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• Peut-on réaliser un bon design Web sans Web-designer ? Quelques pistes de réflexions pour tenter d'y arriver

  Le design des sites aujourd'hui est un point "critique". Et bien souvent les utilisateurs préfèreront un "beau" site à son concurrent moins "évolué" graphiquement. Malheureusement, il n'est pas toujours possible d'avoir à ses côtés un web designer. Dans ce cas, il faut se retrousser les manches et tenter de faire du mieux que l'on peut. Savoir créer un design attrayant ne s'apprend pas en quelques lignes. Cependant voici un petit guide pour débutant qui vous aidera dans la création de votre graphisme. Les contraintes sont nécessaires Même si ça peut sembler contre-intuitif, un bon design part toujours de contraintes bien établies. Si vous pensez que votre projet n'...

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• Most regrettable design or programming decision you made? [closed]

  - by VNarasimhaM

  I would like to hear what kind of design decisions you took and how did they backfire. Because of a bad design decision, I ended up having to support that bad decision forever (I also had a part in it). This made me realize that one single design mistake can haunt you forever. I want to learn from the more experienced people what kind of blunders have they experienced and what did they learn from them. I'm sure this will be a lot of help to other programmers by helping them to not repeat those decisions. Thanks for sharing your experience.

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• translating specifications into query predicates

  - by Jeroen

  I'm trying to find a nice and elegant way to query database content based on DDD "specifications". In domain driven design, a specification is used to check if some object, also known as the candidate, is compliant to a (domain specific) requirement. For example, the specification 'IsTaskDone' goes like: class IsTaskDone extends Specification<Task> { boolean isSatisfiedBy(Task candidate) { return candidate.isDone(); } } The above specification can be used for many purposes, e.g. it can be used to validate if a task has been completed, or to filter all completed tasks from a collection. However, I want to re-use this, nice, domain related specification to query on the database. Of course, the easiest solution would be to retrieve all entities of our desired type from the database, and filter that list in-memory by looping and removing non-matching entities. But clearly that would not be optimal for performance, especially when the entity count in our db increases. Proposal So my idea is to create a 'ConversionManager' that translates my specification into a persistence technique specific criteria, think of the JPA predicate class. The services looks as follows: public interface JpaSpecificationConversionManager { <T> Predicate getPredicateFor(Specification<T> specification, Root<T> root, CriteriaQuery<?> cq, CriteriaBuilder cb); JpaSpecificationConversionManager registerConverter(JpaSpecificationConverter<?, ?> converter); } By using our manager, the users can register their own conversion logic, isolating the domain related specification from persistence specific logic. To minimize the configuration of our manager, I want to use annotations on my converter classes, allowing the manager to automatically register those converters. JPA repository implementations could then use my manager, via dependency injection, to offer a find by specification method. Providing a find by specification should drastically reduce the number of methods on our repository interface. In theory, this all sounds decent, but I feel like I'm missing something critical. What do you guys think of my proposal, does it comply to the DDD way of thinking? Or is there already a framework that does something identical to what I just described?

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• When does logic belong in the Business Object/Entity, and when does it belong in a Service?

  - by Casey

  In trying to understand Domain Driven Design I keep returning to a question that I can't seem to definitively answer. How do you determine what logic belongs to a Domain entity, and what logic belongs to a Domain Service? Example: We have an Order class for an online store. This class is an entity and an aggregate root (it contains OrderItems). Public Class Order:IOrder { Private List<IOrderItem> OrderItems Public Order(List<IOrderItem>) { OrderItems = List<IOrderItem> } Public Decimal CalculateTotalItemWeight() //This logic seems to belong in the entity. { Decimal TotalWeight = 0 foreach(IOrderItem OrderItem in OrderItems) { TotalWeight += OrderItem.Weight } return TotalWeight } } I think most people would agree that CalculateTotalItemWeight belongs on the entity. However, at some point we have to ship this order to the customer. To accomplish this we need to do two things: 1) Determine the postage rate necessary to ship this order. 2) Print a shipping label after determining the postage rate. Both of these actions will require dependencies that are outside the Order entity, such as an external webservice to retrieve postage rates. How should we accomplish these two things? I see a few options: 1) Code the logic directly in the domain entity, like CalculateTotalItemWeight. We then call: Order.GetPostageRate Order.PrintLabel 2) Put the logic in a service that accepts IOrder. We then call: PostageService.GetPostageRate(Order) PrintService.PrintLabel(Order) 3) Create a class for each action that operates on an Order, and pass an instance of that class to the Order through Constructor Injection (this is a variation of option 1 but allows reuse of the RateRetriever and LabelPrinter classes): Public Class Order:IOrder { Private List<IOrderItem> OrderItems Private RateRetriever _Retriever Private LabelPrinter _Printer Public Order(List<IOrderItem>, RateRetriever Retriever, LabelPrinter Printer) { OrderItems = List<IOrderItem> _Retriever = Retriever _Printer = Printer } Public Decimal GetPostageRate { _Retriever.GetPostageRate(this) } Public void PrintLabel { _Printer.PrintLabel(this) } } Which one of these methods do you choose for this logic, if any? What is the reasoning behind your choice? Most importantly, is there a set of guidelines that led you to your choice?

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• Is it possible to build a webpage in Fireworks

  - by Lee Carlton

  I've been building a simple webpage in Fireworks that is very similar to one that we have on our website currently. I just want to make sure that before I go to far I will actually be able to upload this page online through an FTP client. I'm worried because it saves it as a .png file and I don't have a ton of experience with web design.

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• Is there a real code-free webpage design tool ?

  - by Sefler

  Recently I was doing web design. I found that the current web design tool (like Expression Web, Dreamweaver) is terribly coupled with code. Though I managed to use HTML, CSS and many others, I found those tool not free enough when came to design. What I want is a totaly code-free design tool with which I can use to draw the layout, paste pictures, add texts and so on. It doesn't need to have functionality to covert the design into code because I can do it myself. That is to say, I need the software to create a blueprint for me. I'm currently using Photoshop to do this. However it is too stupid in displying the layout (It can't show the width and many other attributes, I had to draw them by myself). Can you find one for me? Thanks in advance.

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• is there a tool that will let me take 'functional screenshots'?

  - by subpixel

  It's one thing to grab screenshots of web sites and return to them for design and interface ideas and inspiration. But increasingly I've found that when I want to examine something that previously caught my eye, the actual web site has since been altered, so I can no longer learn from the code. I wonder: is there a tool available that would allow me to save interfaces in a format that would retain the html/css? Thanks

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• DDD: Aggregate Roots

  - by Mosh

  Hello, I need help with finding my aggregate root and boundary. I have 3 Entities: Plan, PlannedRole and PlannedTraining. Each Plan can include many PlannedRoles and PlannedTrainings. Solution 1: At first I thought Plan is the aggregate root because PlannedRole and PlannedTraining do not make sense out of the context of a Plan. They are always within a plan. Also, we have a business rule that says each Plan can have a maximum of 3 PlannedRoles and 5 PlannedTrainings. So I thought by nominating the Plan as the aggregate root, I can enforce this invariant. However, we have a Search page where the user searches for Plans. The results shows a few properties of the Plan itself (and none of its PlannedRoles or PlannedTrainings). I thought if I have to load the entire aggregate, it would have a lot of overhead. There are nearly 3000 plans and each may have a few children. Loading all these objects together and then ignoring PlannedRoles and PlannedTrainings in the search page doesn't make sense to me. Solution 2: I just realized the user wants 2 more search pages where they can search for Planned Roles or Planned Trainings. That made me realize they are trying to access these objects independently and "out of" the context of Plan. So I thought I was wrong about my initial design and that is how I came up with this solution. So, I thought to have 3 aggregates here, 1 for each Entity. This approach enables me to search for each Entity independently and also resolves the performance issue in solution 1. However, using this approach I cannot enforce the invariant I mentioned earlier. There is also another invariant that states a Plan can be changed only if it is of a certain status. So, I shouldn't be able to add any PlannedRoles or PlannedTrainings to a Plan that is not in that status. Again, I can't enforce this invariant with the second approach. Any advice would be greatly appreciated. Cheers, Mosh

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• .NET Membership with Repository Pattern

  - by Zac

  My team is in the process of designing a domain model which will hide various different data sources behind a unified repository abstraction. One of the main drivers for this approach is the very high probability that these data sources will undergo significant change in the near future and we don't want to be re-writing business logic when this happens. One data source will be our membership database which was originally implemented using the default ASP.Net Membership Provider. The membership provider is tied to the System.Web.Security namespace but we have a design guideline requiring that our domain model layer is not dependent upon System.Web (or any other implementation/environment dependency) as it will be consumed in different environments - nor do we want our websites directly communicating with databases. I am considering what would be a good approach to reconciling the MembershipProvider approach with our abstracted n-tier architecture. My initial feeling is that we could create a "DomainMembershipProvider" which interacts with the domain model and then implement objects in the model which deal with the repository and handle validation/business logic. The repository would then implement data access using our (as-yet undecided) ORM/data access tool. Are there are any glaring holes in this approach - I haven't worked closely with the MembershipProvider class so may well be missing something. Alternatively, is there an approach that you think will better serve the requirements I described above? Thanks in advance for your thoughts and advice. Regards, Zac

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• Php template caching design

  - by Thomas

  Hello to all, I want to include caching in my app design. Caching templates for starters. The design I have used so far is very modular. I have created an ORM implementation for all my tables and each table is represented by the corresponding class. All the requests are handled by one controller which routes them to the appropriate webmethod functions. I am using a template class for handling UI parts. What I have in mind for caching includes the implementation of a separate Cache class for handling caching with the flexibility to either store in files, apc or memcache. Right now I am testing with file caching. Some thoughts Should I include the logic of checking for cached versions in the Template class or in the webmethods which handle the incoming requests and which eventually call the Template class. In the first case, things are pretty simple as I will not have to change anything more than pass the template class an extra argument (whether to load from cache or not). In the second case however, I am thinking of checking for a cached version immediately in the webmethod and if found return it. This will save all the processing done until the logic reaches the template (first case senario). Both senarios however, rely on an accurate mechanism of invalidating caches, which brings as to Invalidating caches As I see it (and you can add your input freely) a template cached file, becomes invalidate if: a. the expiration set, is reached. b. the template file itself is updated (ie by the developer when adding a new line) c. the webmethod that handles the request changes (ie the developer adds/deletes something in the code) d. content coming from the db and ending in the template file is modified I am thinking of storing a json encoded array inside the cached file. The first value will be the expiration timestamp of the cache. The second value will be the modification time of the php file with the code handling the request (to cope with option c above) The third will be the content itself The validation process I am considering, according to the above senarios, is: a. If the expiration of the cached file (stored in the array) is reached, delete the cache file b. if the cached file's mod time is smaller than the template's skeleton file mod time, delete the cached file c. if the mod time of the php file is greated than the one stored in the cache, delete the cached file. d. This is tricky. In the ORM implementation I ahve added event handlers (which fire when adding, updating, deleting objects). I could delete the cache file every time an object thatprovides content to the template, is modified. The problem is how to keep track which cached files correpond to each schema object. Take this example, a user has his shortprofile page and a full profile page (2 templates) These templates can be cached. Now, every time the user modifies his profile, the event handler would need to know which templates or cached files correspond to the User, so that these files can be deleted. I could store them in the db but I am looking for a beter approach

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• Do I must expose the aggregate children as public properties to implement the Persistence ignorance?

  - by xuehua

  Hi all, I'm very glad that i found this website recently, I've learned a lot from here. I'm from China, and my English is not so good. But i will try to express myself what i want to say. Recently, I've started learning about Domain Driven Design, and I'm very interested about it. And I plan to develop a Forum website using DDD. After reading lots of threads from here, I understood that persistence ignorance is a good practice. Currently, I have two questions about what I'm thinking for a long time. Should the domain object interact with repository to get/save data? If the domain object doesn't use repository, then how does the Infrastructure layer (like unit of work) know which domain object is new/modified/removed? For the second question. There's an example code: Suppose i have a user class: public class User { public Guid Id { get; set; } public string UserName { get; set; } public string NickName { get; set; } /// <summary> /// A Roles collection which represents the current user's owned roles. /// But here i don't want to use the public property to expose it. /// Instead, i use the below methods to implement. /// </summary> //public IList<Role> Roles { get; set; } private List<Role> roles = new List<Role>(); public IList<Role> GetRoles() { return roles; } public void AddRole(Role role) { roles.Add(role); } public void RemoveRole(Role role) { roles.Remove(role); } } Based on the above User class, suppose i get an user from the IUserRepository, and add an Role for it. IUserRepository userRepository; User user = userRepository.Get(Guid.NewGuid()); user.AddRole(new Role() { Name = "Administrator" }); In this case, i don't know how does the repository or unit of work can know that user has a new role? I think, a real persistence ignorance ORM framework should support POCO, and any changes occurs on the POCO itself, the persistence framework should know automatically. Even if change the object status through the method(AddRole, RemoveRole) like the above example. I know a lot of ORM can automatically persistent the changes if i use the Roles property, but sometimes i don't like this way because of the performance reason. Could anyone give me some ideas for this? Thanks. This is my first question on this site. I hope my English can be understood. Any answers will be very appreciated.

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• Has test driven development (TDD) actually benefited a real world project?

  - by James

  I am not new to coding. I have been coding (seriously) for over 15 years now. I have always had some testing for my code. However, over the last few months I have been learning test driven design/development (TDD) using Ruby on Rails. So far, I'm not seeing the benefit. I see some benefit to writing tests for some things, but very few. And while I like the idea of writing the test first, I find I spend substantially more time trying to debug my tests to get them to say what I really mean than I do debugging actual code. This is probably because the test code is often substantially more complicated than the code it tests. I hope this is just inexperience with the available tools (RSpec in this case). I must say though, at this point, the level of frustration mixed with the disappointing lack of performance is beyond unacceptable. So far, the only value I'm seeing from TDD is a growing library of RSpec files that serve as templates for other projects/files. Which is not much more useful, maybe less useful, than the actual project code files. In reading the available literature, I notice that TDD seems to be a massive time sink up front, but pays off in the end. I'm just wondering, are there any real world examples? Does this massive frustration ever pay off in the real world? I really hope I did not miss this question somewhere else on here. I searched, but all the questions/answers are several years old at this point. It was a rare occasion when I found a developer who would say anything bad about TDD, which is why I have spent as much time on this as I have. However, I noticed that nobody seems to point to specific real-world examples. I did read one answer that said the guy debugging the code in 2011 would thank you for have a complete unit testing suite (I think that comment was made in 2008). So, I'm just wondering, after all these years, do we finally have any examples showing the payoff is real? Has anybody actually inherited or gone back to code that was designed/developed with TDD and has a complete set of unit tests and actually felt a payoff? Or did you find that you were spending so much time trying to figure out what the test was testing (and why it was important) that you just tossed out the whole mess and dug into the code?

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• Delphi 2010 Datasnap - Design Query

  - by Matt

  I am investigating moving a thick client SQL based Delphi application to Multi Tier thin clients, and have been looking at using Datasnap in Delphi 2010. I have worked through the White Paper written by Bob Swart and extended this further. My main question really is that I want to make the server side efficient in terms of connections and SQL Queries due to multiple queries being run and remaining open at the same time to interrogate data, can anyone point me in a direction for guidance on how to design a real world Datasnap Server application, as the demo's don't go into enough detail. Thanks Matt

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• Designing a game database

  - by Ronald

  I'm trying to design a database to record game histories for a game I'm working on. I have 3 different tables: users, gamehistories, and gamescores. Columns for tables: users: uid, displayname, email gamehistories: gid, pubID, start (datetime), end (datetime) gamescores: gid, uid, score I am trying to produce the following result set given a userID (uid): Opponent's displayname, my score, opponent's score, duration Any ideas? Is my design ok? How can I query these tables to get game histories for a given uid?

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• Git & Web-design: handling multiple customized templates

  - by o_O Tync

  I'm developing a CMS (with Django, but that doesn't matter) and have chosen GIT. Installations will vary in: Configs Database contents Media Templates First 3 are not a problem with git: we simply don't need these :) While developing, I have 1 default template with related media. Later, each customer will receive his own design based on default templates (some slight customization). I'm not going to support each of the custom templates as I introduce new features. Modularity helps with this but is not a 100% solution. Do you have any experience to share?

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• What's the best Communication Pattern for EJB3-based applications?

  - by Hank

  I'm starting a JEE project that needs to be strongly scalable. So far, the concept was: several Message Driven Beans, responsible for different parts of the architecture each MDB has a Session Bean injected, handling the business logic a couple of Entity Beans, providing access to the persistence layer communication between the different parts of the architecture via Request/Reply concept via JMS messages: MDB receives msg containing activity request uses its session bean to execute necessary business logic returns response object in msg to original requester The idea was that by de-coupling parts of the architecture from each other via the message bus, there is no limit to the scalability. Simply start more components - as long as they are connected to the same bus, we can grow and grow. Unfortunately, we're having massive problems with the request-reply concept. Transaction Mgmt seems to be in our way plenty. It seams that session beans are not supposed to consume messages?! Reading http://blogs.sun.com/fkieviet/entry/request_reply_from_an_ejb and http://forums.sun.com/message.jspa?messageID=10338789, I get the feeling that people actually recommend against the request/reply concept for EJBs. If that is the case, how do you communicate between your EJBs? (Remember, scalability is what I'm after) Details of my current setup: MDB 1 'TestController', uses (local) SLSB 1 'TestService' for business logic TestController.onMessage() makes TestService send a message to queue XYZ and requests a reply TestService uses Bean Managed Transactions TestService establishes a connection & session to the JMS broker via a joint connection factory upon initialization (@PostConstruct) TestService commits the transaction after sending, then begins another transaction and waits 10 sec for the response Message gets to MDB 2 'LocationController', which uses (local) SLSB 2 'LocationService' for business logic LocationController.onMessage() makes LocationService send a message back to the requested JMSReplyTo queue Same BMT concept, same @PostConstruct concept all use the same connection factory to access the broker Problem: The first message gets send (by SLSB 1) and received (by MDB 2) ok. The sending of the returning message (by SLSB 2) is fine as well. However, SLSB 1 never receives anything - it just times out. I tried without the messageSelector, no change, still no receiving message. Is it not ok to consume message by a session bean? SLSB 1 - TestService.java @Resource(name = "jms/mvs.MVSControllerFactory") private javax.jms.ConnectionFactory connectionFactory; @PostConstruct public void initialize() { try { jmsConnection = connectionFactory.createConnection(); session = jmsConnection.createSession(false, Session.AUTO_ACKNOWLEDGE); System.out.println("Connection to JMS Provider established"); } catch (Exception e) { } } public Serializable sendMessageWithResponse(Destination reqDest, Destination respDest, Serializable request) { Serializable response = null; try { utx.begin(); Random rand = new Random(); String correlationId = rand.nextLong() + "-" + (new Date()).getTime(); // prepare the sending message object ObjectMessage reqMsg = session.createObjectMessage(); reqMsg.setObject(request); reqMsg.setJMSReplyTo(respDest); reqMsg.setJMSCorrelationID(correlationId); // prepare the publishers and subscribers MessageProducer producer = session.createProducer(reqDest); // send the message producer.send(reqMsg); System.out.println("Request Message has been sent!"); utx.commit(); // need to start second transaction, otherwise the first msg never gets sent utx.begin(); MessageConsumer consumer = session.createConsumer(respDest, "JMSCorrelationID = '" + correlationId + "'"); jmsConnection.start(); ObjectMessage respMsg = (ObjectMessage) consumer.receive(10000L); utx.commit(); if (respMsg != null) { response = respMsg.getObject(); System.out.println("Response Message has been received!"); } else { // timeout waiting for response System.out.println("Timeout waiting for response!"); } } catch (Exception e) { } return response; } SLSB 2 - LocationService.Java (only the reply method, rest is same as above) public boolean reply(Message origMsg, Serializable o) { boolean rc = false; try { // check if we have necessary correlationID and replyTo destination if (!origMsg.getJMSCorrelationID().equals("") && (origMsg.getJMSReplyTo() != null)) { // prepare the payload utx.begin(); ObjectMessage msg = session.createObjectMessage(); msg.setObject(o); // make it a response msg.setJMSCorrelationID(origMsg.getJMSCorrelationID()); Destination dest = origMsg.getJMSReplyTo(); // send it MessageProducer producer = session.createProducer(dest); producer.send(msg); producer.close(); System.out.println("Reply Message has been sent"); utx.commit(); rc = true; } } catch (Exception e) {} return rc; } sun-resources.xml <admin-object-resource enabled="true" jndi-name="jms/mvs.LocationControllerRequest" res-type="javax.jms.Queue" res-adapter="jmsra"> <property name="Name" value="mvs.LocationControllerRequestQueue"/> </admin-object-resource> <admin-object-resource enabled="true" jndi-name="jms/mvs.LocationControllerResponse" res-type="javax.jms.Queue" res-adapter="jmsra"> <property name="Name" value="mvs.LocationControllerResponseQueue"/> </admin-object-resource> <connector-connection-pool name="jms/mvs.MVSControllerFactoryPool" connection-definition-name="javax.jms.QueueConnectionFactory" resource-adapter-name="jmsra"/> <connector-resource enabled="true" jndi-name="jms/mvs.MVSControllerFactory" pool-name="jms/mvs.MVSControllerFactoryPool" />

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• 'schema' design for a social network

  - by Alan B

  I'm working on a proof of concept app for a twitter style social network with about 500k users. I'm unsure of how best to design the 'schema' should I embed a user's subscriptions or have a separate 'subscriptions' collection and use db references? If I embed, I still have to perform a query to get all of a user's followers. e.g. Given the following user: { "username" : "alan", "photo": "123.jpg", "subscriptions" : [ {"username" : "john", "status" : "accepted"}, {"username" : "paul", "status" : "pending"} ] } to find all of alan's subscribers, I'd have to run something like this: db.users.find({'subscriptions.username' : 'alan'}); from a performance point of view, is that any worse or better than having a separate subscriptions collection? also, when displaying a list of subscriptions/subscribers, I am currently having problems with n+1 because the subscription document tells me the username of the target user but not other attributes I may need such as the profile photo. Are there any recommended practices for such situations? thanks Alan

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• OOP vs PP for algorithms

  - by Ilian

  Which paradigm is better for design and analysis of algorithms? Which is faster? Because I have a subject called Design and Analysis of Algorithms in university and have a time limit for programs. Is OOP slower than Procedure programming? Or the time difference is not big?

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• How do I design the file storage issue?

  - by user102533

  I am working on an application that creates video files and stores them in a folder in the C:\ drive. I speculate that there will be a large number of these files in the future and we would run out of disk space at some point of time (on our VPS). When the time comes that we have to upgrade, we either plan to use one of the Cloud providers to store files or our existing provider can add another disk (say D:\ drive). Either way, I would want to design the app now in a way that in future, moving to different locations would not be an issue and would be transparent to the end user. The code that creates these files supports 2 ways: myObj.SetOutputToDisk(<path to store>); or myObj.SetOutputToMemoryStream(ms); If we go with the Cloud architecture, I assume we might have the following combination: Cloud Files + Existing VPS or Cloud Files + Cloud Windows Server Given the unknowns at this time, how would I go about designing this?

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• Design Time Attribute For CSS Class in ASP.net Custom Server Control

  - by Jon P

  Hopefully some Custom Control Designers/Builders can help I'm attempting to build my first custom control that is essential a client detail collection form. There are to be a series of elements to this form that require various styles applied to them. Ideally I'd like the VS 2005/2008 properties interface to be able to apply the CSSClass as it does at the control level, i.e. with a dropdown list of available CSS Clases. Take for example the Class to be applied to the legend tag /// <summary>Css Class for Legend</summary> [Category("Appearance")] [Browsable(true)] [DefaultValue("")] //I am at a loss as to what goes in [Editor] [Editor(System.Web.UI.CssStyleCollection), typeof(System.Drawing.Design.UITypeEditor))] public string LegendCSSClass { get { return _LegendCSSClass; } set { _LegendCSSClass = value; } } I have tried a couple of options, as you can see from above, without much luck. Hopefully there is something simple I am missing. I'd also be happy for references pertaining to the [Editor] attribute

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• EJB 3 Session Bean Design for Simple CRUD

  - by sdoca

  I am writing an application that's sole purpose in life is to do CRUD operations for maintaining records in database. There are relationships between some of the tables/entities. Most examples I've seen for creating session beans deals with complex business logic/operations that interact with many entities which I don't have. Since my application is so very basic, what would be the best design for the session bean(s)? I was thinking of having one session bean per entity which had CRUD the methods defined. Then I thought of combining all of those session beans into a single session bean. And then I found this blog entry which is intriguing, but I must admit I don't understand all of it (what is a ServiceFacade?). I'm leaning towards session bean/entity class, but would like to hear more experienced opinions. Thanks.

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