Search Results

Search found 8692 results on 348 pages for 'patterns and practices'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 154/348 | < Previous Page | 150 151 152 153 154 155 156 157 158 159 160 161  | Next Page >

  • [MySQL] Efficiently store last X records per item

    - by Saif Bechan
    I want to store the last X records in an MySQL database in an efficient way. So when the 4th record is stored the first should be deleted. The way I do this not is first run a query getting the items. Than check what I should do then insert/delete. There has to be a better way to do this. Any suggestions? Edit I think I should add that the records stored do not have a unique number. They have a mixed par. For example article_id and user_id. Then I want to make a table with the last X items for user_x. Just selecting the article from the table grouped by user and sorted by time is not an option for me. The table where I do the sort and group on has millions of records and gets hit a lot for no reason. So making a table in between with the last X records is way more effient. PS. I am not using this for articles and users.

    Read the article

  • Best Practice: Software Versioning

    - by Sebi
    I couldn't find a similar question here on SO, but if you find one please link. Is there any guideline or standard best practice how to version a software you develop in your spare time for fun, but nevertheless will be used by some people? I think it's necessary to version such software so that you know about with version one is talking about (e.g. for bug fixing, support, and so on). But where do I start the versioning? 0.0.0? or 0.0? And then how to I increment the numbers? major release.minor change? and should'nt any commit to a version control system be another version? or is this only for versions which are used in a productive manner?

    Read the article

  • Tips for Using Multiple Development Systems

    - by Tim Lytle
    When I travel, I don't pack up the desktop I use in the office and take it with me. Maybe I should, but I don't. However, since I'm a contract programmer I like to be able to work wherever I am: I'm mostly thinking of web development here. Version Control goes a long way in keeping sane and working on multiple projects on multiple systems (two or three computers); however, there are the issues of: IDE settings - different display sizes mean the IDE settings can't be completely synced, if at all. Database - if the database is 'external' (even if it's running on the same system, it's not in version control), how do you maintain the needed syncs of structure. Development Stack - Some projects need non-standard extensions, libraries, etc installed. Just an overview of some of the hassle involved with developing on multiple systems. I'll probably end up asking some specific questions, but I thought a CW style tips might reveal some things I would even think to ask about. Update: I guess this would also address tips to make upgrading/replacing your development system easier (something I've just done). So, one tip per answer please, so the 'top' tips are easy to find. How do you make it easier to develop on multiple systems, or to transfer work after upgrading/replaceing a development system?

    Read the article

  • Converting ASP.NET MVC to n-Tiered Architecture

    - by Jeff
    I just built an application using ASP.NET MVC. The programmers at my company want to build all future modules using n-Tiered (Presentation Layer, Business Logic Layer, Data Access Layer) architecture. I am not the programmer and need to know why this makes sense? Do I have to completely rewrite the entire code or can it be converted? We are building an HRIS system with Business Intelligence. Somebody please explain why or why not this approach does or does not make sense.

    Read the article

  • What Getters and Setters should and shouldn't do.

    - by cyclotis04
    I've run into a lot of differing opinions on Getters and Setters lately, so I figured I should make it into it's own question. A previous question of mine received an immediate comment (later deleted) that stated setters shouldn't have any side effects, and a SetProperty method would be a better choice. Indeed, this seems to be Microsoft's opinion as well. However, their properties often raise events, such as Resized when a form's Width or Height property is set. OwenP also states "you shouldn't let a property throw exceptions, properties shouldn't have side effects, order shouldn't matter, and properties should return relatively quickly." Yet Michael Stum states that exceptions should be thrown while validating data within a setter. If your setter doesn't throw an exception, how could you effectively validate data, as so many of the answers to this question suggest? What about when you need to raise an event, like nearly all of Microsoft's Control's do? Aren't you then at the mercy of whomever subscribed to your event? If their handler performs a massive amount of information, or throws an error itself, what happens to your setter? Finally, what about lazy loading within the getter? This too could violate the previous guidelines. What is acceptable to place in a getter or setter, and what should be kept in only accessor methods?

    Read the article

  • Is it good practice to put private API in the .m files and public API in .h files in Cocoa?

    - by Paperflyer
    Many of my classes in my current project have several properties and methods that are only ever called from within the class itself. Also, they might mess with the working of the class depending on the current state of the class. Currently, all these interfaces are defined in the main interface declaration in the .h files. Is it considered good practice to put the “private” methods and properties at the top of the .m files? This won't ever affect anything since I am very likely the only person ever to look at this source code, but of course it would be interesting to know for future projects.

    Read the article

  • Best way to unit test Collection?

    - by limc
    I'm just wondering how folks unit test and assert that the "expected" collection is the same/similar as the "actual" collection (order is not important). To perform this assertion, I wrote my simple assert API:- public void assertCollection(Collection<?> expectedCollection, Collection<?> actualCollection) { assertNotNull(expectedCollection); assertNotNull(actualCollection); assertEquals(expectedCollection.size(), actualCollection.size()); assertTrue(expectedCollection.containsAll(actualCollection)); assertTrue(actualCollection.containsAll(expectedCollection)); } Well, it works. It's pretty simple if I'm asserting just bunch of Integers or Strings. It can also be pretty painful if I'm trying to assert a collection of Hibernate domains, say for example. The collection.containsAll(..) relies on the equals(..) to perform the check, but I always override the equals(..) in my Hibernate domains to check only the business keys (which is the best practice stated in the Hibernate website) and not all the fields of that domain. Sure, it makes sense to check just against the business keys, but there are times I really want to make sure all the fields are correct, not just the business keys (for example, new data entry record). So, in this case, I can't mess around with the domain.equals(..) and it almost seems like I need to implement some comparators for just unit testing purposes instead of relying on collection.containsAll(..). Are there some testing libraries I could leverage here? How do you test your collection? Thanks.

    Read the article

  • .net design pattern question

    - by user359562
    Hi. I am trying to understand design pattern problems. I am trying to modify the code like this in winforms and trying to see if any design pattern suits my requirement. Please suggest which is the best design pattern in this scenario. This is very basic code containing 2 tab pages which might have different controls can be added dynamically and read out different files on click of particular tab. To elaborate more... I have written this code to learn and understand design pattern. This is just a scenario where user click on a particular tab which will show dynamic controls generated. public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void tabControl1_SelectedIndexChanged(object sender, EventArgs e) { if (tabControl1.SelectedTab.Name.Equals("tabPage1")) { GeneratedynamicControlsForTab1(); } else if (tabControl1.SelectedTab.Name.Equals("tabPage2")) { GeneratedynamicControlsForTab2(); } } private void GeneratedynamicControlsForTab1() { Label label1 = new Label(); label1.Text = "Label1"; tabPage1.Controls.Add(label1); ReadCSVFile(); } private void GeneratedynamicControlsForTab2() { tabPage1.Controls.Clear(); Label label2 = new Label(); label2.Text = "Label2"; tabPage2.Controls.Add(label2); ReadTextFile(); } private void ReadCSVFile() { } private void ReadTextFile() { } }

    Read the article

  • Preprocessor "macro function" vs. function pointer - best practice?

    - by Dustin
    I recently started a small personal project (RGB value to BGR value conversion program) in C, and I realised that a function that converts from RGB to BGR can not only perform the conversion but also the inversion. Obviously that means I don't really need two functions rgb2bgr and bgr2rgb. However, does it matter whether I use a function pointer instead of a macro? For example: int rgb2bgr (const int rgb); /* * Should I do this because it allows the compiler to issue * appropriate error messages using the proper function name, * not to mention possible debugging benefits? */ int (*bgr2rgb) (const int bgr) = rgb2bgr; /* * Or should I do this since it is merely a convenience * and they're really the same function anyway? */ #define bgr2rgb(bgr) (rgb2bgr (bgr)) I'm not necessarily looking for a change in execution efficiency as it's more of a subjective question out of curiosity. I am well aware of the fact that type safety is neither lost nor gained using either method. Would the function pointer merely be a convenience or are there more practical benefits to be gained of which I am unaware?

    Read the article

  • objectWithFieldNAme Best Practice for CoreData

    - by Rafael
    Hello, I'm trying to implements some methods for my CoreData models and I'm wonndering if the way I'm doing it is a good practice. I want to implement methods of the type getObjectsWithFieldName. This methods could be used by severals views. So the way I'm doing it is implementing a Class method in the model in the following way: +(NSArray *)getObjectWithFieldName:(NSString *)fieldName andContext:(NSManagedObjectContext *) context; Is this a good practice? Or there is another way to do it for iPhone Development? Thanks in advanced.

    Read the article

  • How to Communicate between minifb and a GAE-Hosted Silverlight Client

    - by Nick Gotch
    I have a minifb app (technically gminifb) running on Google App Engine with a bunch of handlers for processing all kinds of requests from a Silverlight client. What's the recommended approach for adding the FB GET variables, such as fb_sig, to the HTTP requests? I believe I can technically pass the session key and uid directly and get things to work but it seems there's probably a much better way to do this. I was reading about FBJS AJAX and I'm trying to figure out how I can use it to proxy the HTTP requests from the Silverlight client through it. Is this a good way to do it? And if so, how would I go about doing so? Any other recommendations would be appreciated too. Thanks,

    Read the article

  • SQL Server error handling: exceptions and the database-client contract

    - by gbn
    We’re a team of SQL Servers database developers. Our clients are a mixed bag of C#/ASP.NET, C# and Java web services, Java/Unix services and some Excel. Our client developers only use stored procedures that we provide and we expect that (where sensible, of course) they treat them like web service methods. Some our client developers don’t like SQL exceptions. They understand them in their languages but they don’t appreciate that the SQL is limited in how we can communicate issues. I don’t just mean SQL errors, such as trying to insert “bob” into a int column. I also mean exceptions such as telling them that a reference value is wrong, or that data has already changed, or they can’t do this because his aggregate is not zero. They’d don’t really have any concrete alternatives: they’ve mentioned that we should output parameters, but we assume an exception means “processing stopped/rolled back. How do folks here handle the database-client contract? Either generally or where there is separation between the DB and client code monkeys. Edits: we use SQL Server 2005 TRY/CATCH exclusively we log all errors after the rollback to an exception table already we're concerned that some of our clients won't check output paramaters and assume everything is OK. We need errors flagged up for support to look at. everything is an exception... the clients are expected to do some message parsing to separate information vs errors. To separate our exceptions from DB engine and calling errors, they should use the error number (ours are all 50,000 of course)

    Read the article

  • Why is using a common-lookup table to restrict the status of entity wrong?

    - by FreshCode
    According to Five Simple Database Design Errors You Should Avoid by Anith Sen, using a common-lookup table to store the possible statuses for an entity is a common mistake. Why is this wrong? I disagree that it's wrong, citing the example of jobs at a repair service with many possible statuses that generally have a natural flow, eg.: Booked In Assigned to Technician Diagnosing problem Waiting for Client Confirmation Repaired & Ready for Pickup Repaired & Couriered Irreparable & Ready for Pickup Quote Rejected Arguably, some of these statuses can be normalised to tables like Couriered Items, Completed Jobs and Quotes (with Pending/Accepted/Rejected statuses), but that feels like unnecessary schema complication. Another common example would be order statuses that restrict the status of an order, eg: Pending Completed Shipped Cancelled Refunded The status titles and descriptions are in one place for editing and are easy to scaffold as a drop-down with a foreign key for dynamic data applications. This has worked well for me in the past. If the business rules dictate the creation of a new order status, I can just add it to OrderStatus table, without rebuilding my code.

    Read the article

  • What is the recommended way of parsing an XML feed with multiple namespaces with ActionScript 3.0?

    - by dafko
    I have seen the following methods to be used in several online examples, but haven't found any documentation on the recommended way of parsing an XML feed. Method 1: protected function xmlResponseHandler(event:ResultEvent):void { var atom:Namespace = new Namespace("http://www.w3.org/2005/Atom"); var microsoftData:Namespace = new Namespace("http://schemas.microsoft.com/ado/2007/08/dataservices"); var microsoftMetadata:Namespace = new Namespace("http://schemas.microsoft.com/ado/2007/08/dataservices/metadata"); var ac:ArrayCollection = new ArrayCollection(); var keyValuePairs:KeyValuePair; var propertyList:XMLList = (event.result as XML)..atom::entry.atom::content.microsoftMetadata::properties; for each (var properties:XML in propertyList) { keyValuePairs = new KeyValuePair(properties.microsoftData::FieldLocation, properties.microsoftData::Locationid); ac.addItem(keyValuePairs); } cb.dataProvider = ac; } Method 2: protected function xmlResponseHandler(event:ResultEvent):void { namespace atom = "http://www.w3.org/2005/Atom"; namespace d = "http://schemas.microsoft.com/ado/2007/08/dataservices"; namespace m = "http://schemas.microsoft.com/ado/2007/08/dataservices/metadata"; use namespace d; use namespace m; use namespace atom; var ac:ArrayCollection = new ArrayCollection(); var keyValuePairs:KeyValuePair; var propertyList:XMLList = (event.result as XML)..entry.content.properties; for each (var properties:XML in propertyList) { keyValuePairs = new KeyValuePair(properties.FieldLocation, properties.Locationid); ac.addItem(keyValuePairs); } cb.dataProvider = ac; } Sample XML feed: <?xml version="1.0" encoding="iso-8859-1" standalone="yes"?> <feed xml:base="http://www.test.com/Test/my.svc/" xmlns:d="http://schemas.microsoft.com/ado/2007/08/dataservices" xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata" xmlns="http://www.w3.org/2005/Atom"> <title type="text">Test_Locations</title> <id>http://www.test.com/test/my.svc/Test_Locations</id> <updated>2010-04-27T20:41:23Z</updated> <link rel="self" title="Test_Locations" href="Test_Locations" /> <entry> <id>1</id> <title type="text"></title> <updated>2010-04-27T20:41:23Z</updated> <author> <name /> </author> <link rel="edit" title="Test_Locations" href="http://www.test.com/id=1" /> <category term="MySQLModel.Test_Locations" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme" /> <content type="application/xml"> <m:properties> <d:FieldLocation>Test Location</d:FieldLocation> <d:Locationid>test0129</d:Locationid> </m:properties> </content> </entry> <entry> <id>2</id> <title type="text"></title> <updated>2010-04-27T20:41:23Z</updated> <author> <name /> </author> <link rel="edit" title="Test_Locations" href="http://www.test.com/id=2" /> <category term="MySQLModel.Test_Locations" scheme="http://schemas.microsoft.com/ado/2007/08/dataservices/scheme" /> <content type="application/xml"> <m:properties> <d:FieldLocation>Yet Another Test Location</d:FieldLocation> <d:Locationid>test25</d:Locationid> </m:properties> </content> </entry> </feed>

    Read the article

  • Looking for design help

    - by jess
    I have this scenario in most of the WindowsForms having grids I have a sequence of code which is similar - AddNewRow(in grid),CreateNewEntity,notifyUser,few other steps Now, I want to use a template kind of pattern.But,my issue is with CreateEntity method since sometimes it is passed a parameter which is different depending on the type of object being created.Should I make createentity accept an "object" type,and cast when the parameter is to be used.What other way can I tackle this design issue? Also,CreateEntity returns the object being created.

    Read the article

  • Java: Make a method abstract for each extending class

    - by Martijn Courteaux
    Hi, Is there any keyword or design pattern for doing this? public abstract class Root { public abstract void foo(); } public abstract class SubClass extends Root { public void foo() { // Do something } } public class SubberClass extends SubClass { // Here is it not necessary to override foo() // So is there a way to make this necessary? // A way to obligate the developer make again the override } Thanks

    Read the article

  • What is the best Design/Way to keep user connected ?

    - by Fasih Hansmukh
    Am working on a POC for self learning in which I want to keep my user connected in LIVE pattern. For example, A game in which 4 user can play at a time , here I need to keep this user connected to my game . M not good at Socket type of programming and love to do that in Services way.What i wana know is 'What is the best way of doing this'. According to my initial Brain Storming, I have decided that I will use SilverLight(In Browser Or Out of Browser) as Front end [I have no issue in that]. I m more concern in back end. Either I make an handler or make a WCF service or use full duplex service and use pooling mechanism for that. As a random thought I come up with a Timer type logic that will fire every after 10 seconds at clients end and get status like Is it now Its turn to roll a dice Home many user left (in case if some of them left) What are connected user status in game like there score/points ect and update game view according to this at his end Kindly place your best answers here that will help me to learn this. Regards and thanks in Advance EDIT: Starting Bounty as i need more feedback. FH

    Read the article

  • How can I handle multiple views of a data object? Which design pattern is acceptable?

    - by tranquil.byte
    I have a person object. class Person { private $name; ... } I need to be able to change how they are displayed on the front-end ( visitors have control ). They can choose list view, grid view, photo view for example. class PersonDisplay { public function displayList() { // Query database // Output html to display in list mode } public function displayPhoto() { // Query database // Output html to display in photo mode } } Is this an acceptable way to handle the presentation of the items on the front-end or is there a specific design pattern I should be researching to help me with this task? Does anyone have any suggestions or ideas where this could go wrong or if this could potentially make maintenance a nightmare? The Person object was just an example very similiar to what I am using.

    Read the article

  • how to share a variable between two threads

    - by prmatta
    I just inherited some code, two threads within this code need to perform a system task. One thread should do the system task before the other thread. They should not be performing the system task together. The two threads do not have references to each other. Now, I know I can use some sort of a semaphore to achieve this. But my question is what is the right way to get both threads to access this semaphore. I could create a static variable/method a new class : public class SharedSemaphore { private static Semaphore s = new Semaphore (1, true); public static void performSystemTask () { s.acquire(); } public static void donePerformingSystemTask() { s.release(); } } This would work (right?) but this doesn't seem like the right thing to do. Because, the threads now have access to a semaphore, without ever having a reference to it. This sort of thing doesn't seem like a good programming practice. Am I wrong?

    Read the article

  • Is this physical collection class that contains only static methods an Anti-Pattern?

    - by Tj Kellie
    I'm trying to figure out if I should continue on with a current pattern in an application I'm working in, or refactor this into something else. I have a set of collection classes off a generic base of List. These classes have public constructors but contain only static methods that return collections. They look like this: public class UserObjCollection : BaseCollection<UserObj> { public static UserObjCollection GetAllUserObj() { UserObjCollection obj = new UserObjCollection(); obj.MapObjects(new UserObjDataService().GetAllUserObj()); return obj; } } Is this a Pattern or Anti-Pattern and what are the merits of this over a straight factory pattern?

    Read the article

  • "requiresuniqueemail=true" implementation in asp.net site

    - by domineer
    Hi people I got a social networking site that is running live right now.The first time I launched my site I let requiresuniqueemail=false set-up on my web.config inorder for me to create dummy accounts for testing purposes and to start up the site you know.However the site is kind of stable right now w/ almost 5k members.So I would like to set-up the requiresuniqueemail to true so that users cannot reuse their existing email address and for me to make it sure that there will be unique email ad for each site user.I know the site got like 100 users with the same email address.My question is what could be the problem I'm going to face if I do this right now(requiresuniqueemail="true") and how to do this efficiently(without errors and if possible sitewide say in the global assax)?I tested and I already got an error if I logout an account.Like say a user try to click log-out this code runs: Dim d As DateTime = DateTime.Now.AddMinutes(-1 * Membership.UserIsOnlineTimeWindow) Dim theuser As MembershipUser = Membership.GetUser() theuser.LastActivityDate = d Membership.UpdateUser(theuser) If Not Cache(Page.User.Identity.Name.ToLower() + "currentstatus") Is Nothing Then Cache.Remove(Page.User.Identity.Name.ToLower() + "currentstatus") End If Then an exception occured on updateuser() function saying System.Configuration.Provider.ProviderException: The E-mail supplied is invalid. This is just one instance I know that I encountered a problem. Hoping to hear your ideas guys.....

    Read the article

  • Code promotion: Enforcing the rules

    - by jbarker7
    So here is our problem: We have a small team of developers with their own ways of doing things-- I am trying to formalize a process in which we are required to promote our code in the following order: Local sandbox Dev UAT Staging Live Developers develop/test as they go on their own sandbox, Dev is its own box that we would use for continuous integration, UAT is another site in IIS on the dev box, which uses our dev database. We then promote to staging, which is a site in IIS on the Live box and using live data (just like the live, hence staging). Then, finally, we promote to live. Here are a few of my questions: 1.) Does this seem to be best practice? If not, what needs to be done differently? 2.) How do I enforce the rules to the developers? Often developers skip steps in order to save time... this should not be tolerated and would be great if it could be physically enforced. 3.) How do I enforce these rules to the business group? The business group just wants to get features out FAST. Do we promote only on certain days? Thanks! Josh

    Read the article

  • standard debugging way for javascript/jquery

    - by ZX12R
    This is my usual way to debug javascript. Include alert(0); to break the flow and find out what is happening. sometimes when i need multiple check points i do alert('the flow is now in function 1'); alert('the flow is now in function 2'); or sometimes just alert('success'); i would like to know if there is any standard way for debugging adopted as i am finding my current method very intrusive. thanks in advance..:)

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 150 151 152 153 154 155 156 157 158 159 160 161  | Next Page >