Search Results

Search found 17921 results on 717 pages for 'cocoa design patterns'.

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 379/717 | < Previous Page | 375 376 377 378 379 380 381 382 383 384 385 386  | Next Page >

  • NHibernate Queries with Values Produced by Business Logic

    - by Lewis
    I have an NH query which returns a Product with a BasePrice. Depending on various other factors, such as Manufacturer price markup, I use a PricingService on the C# side of things to produce a "final" price. The issue is that I now need to query against this final value - i.e., I need to run a query that selects Products within a particular "final" price range. I'm thinking that my approach to this is all wrong, but I really didn't want to put the logic of the final price calculation in a SQL function or something like that, so any suggestions would be appreciated.

    Read the article

  • Why did the C# designers attach three different meanings to the 'using' keyword?

    - by gWiz
    The using keyword has three disparate meanings: type/namespace aliasing namespace import syntactic sugar for ensuring Dispose is called The documentation calls the first two definitions directives (which I'm guessing means they are preprocessing in nature), while the last is a statement. Regardless of the fact that they are distinguished by their syntaxes, why would the language developers complicate the semantics of the keyword by attaching three different meanings to it? For example, (disclaimer: off the top of my head, there may certainly be better examples) why not add keywords like alias and import? Technical, theoretical, or historical reasons? Keyword quota? ;-) Contrived sample: import System.Timers; alias LiteTimer=System.Threading.Timer; alias WinForms=System.Windows.Forms; public class Sample { public void Action { var elapsed = false; using(var t = new LiteTimer.Timer(_ => elapsed = true) { while (!elapsed) CallSomeFinickyApi(); } } } "Using" is such a vague word.

    Read the article

  • Is there anything wrong with a class with all static methods?

    - by MatthewMartin
    I'm doing code review and came across a class that uses all static methods. The entrance method takes several arguments and then starts calling the other static methods passing along all or some of the arguments the entrance method received. It isn't like a Math class with largely unrelated utility functions. In my own normal programming, I rarely write methods where Resharper pops and says "this could be a static method", when I do, they tend to be mindless utility methods. Is there anything wrong with this pattern? Is this just a matter of personal choice if the state of a class is held in fields and properties or passed around amongst static methods using arguments?

    Read the article

  • Locking DB w/ Large Reads (Ruby-on-Rails/Heroku)

    - by Splashlin
    Currently I have a Web API running on Heroku that is constantly writing information we're collecting from other data sources (currently theres about half a GB of data and it's growing very quickly). We're looking to add a reporting system on top of the current database that we can use to extract useful information out of the DB. The problem is that when we're running reports we're locking the DB and any other sites communicating with the DB are timing out. Does anyone have any solutions on how to solve this type of issue? Amazon RDS seems to have some interesting stuff with database replication but I don't know if that will solve my problems. Any advice would be greatly appreciated. Thanks

    Read the article

  • Tags php improving database speed and user experience

    - by Doodle
    How did stackOverFlow, excuse me if it wasn't the first implementation of this system. Decide what its initial tags where? I want to provide users with the best experience on my site and am implementing a tags system. I don't care about search engines or any of that. I just care about my users. Does any one have any advice about things that have failed or succeeded when they allowed users to tag things? Does any one know some good resources about the methodologies of user tagging? Does any one know some good resources about implementing a tags system from a programming perspective, database structures, theories, etc ? I'll give my check to who ever I feel points me in the best direction on the subject.

    Read the article

  • Storing information for drop-down menus

    - by Mark
    Suppose you're building an HTML form and you want to have 2 or more drop-down menus, where after picking an option from the first, the 2nd menu is populated, and so forth. For example, choosing a country would bring up a list of provinces for that country, which would in turn list the cities. How would you store that sort of information in a database? Would you have a table Countries(id, name), Provinces(id, country_id, name), Cities(id, province_id, name) or would you have just one big denormalized table Entries(country, province, city)? (Why?)

    Read the article

  • Do null SQLite Data fields take up extra memory?

    - by CSharperWithJava
    I'm using the built in sqlite library on the Android platform. I'm considering adding several general purpose fields that users will be able to use for their own custom applications, but these fields will be blank most of the time. My question is, how much overhead will these blank fields add to my database? Do null fields even take up per record memory in sqlite? If so, how much? I don't quite understand the inner workings of a sqlite database.

    Read the article

  • Too many columns to index - use mySQL Partitions?

    - by Christopher Padfield
    We have an application with a table with 20+ columns that are all searchable. Building indexes for all these columns would make write queries very slow; and any really useful index would often have to be across multiple columns increasing the number of indexes needed. However, for 95% of these searches, only a small subset of those rows need to be searched upon, and quite a small number - say 50,000 rows. So, we have considered using mySQL Partition tables - having a column that is basically isActive which is what we divide the two partitions by. Most search queries would be run with isActive=1. Most queries would then be run against the small 50,000 row partition and be quick without other indexes. Only issue is the rows where isActive=1 is not fixed; i.e. it's not based on the date of the row or anything fixed like that; we will need to update isActive based on use of the data in that row. As I understand it that is no problem though; the data would just be moved from one partition to another during the UPDATE query. We do have a PK on id for the row though; and I am not sure if this is a problem; the manual seemed to suggest the partition had to be based on any primary keys. This would be a huge problem for us because the primary key ID has no basis on whether the row isActive.

    Read the article

  • When/Why to use Cascading in SQL Server?

    - by Joel Coehoorn
    When setting up foreign keys in SQL Server, under what circumstances should you have it cascade on delete or update, and what is the reasoning behind it? This probably applies to other databases as well. I'm looking most of all for concrete examples of each scenario, preferably from someone who has used them successfully.

    Read the article

  • Should I use a huge composite primary key or just a unique id?

    - by Jack
    I have been trying to do web scraping of a particular site and storing the results in a database. My original assumptions about the data allowed a schema where I could use fairly reasonable composite primary keys (usually containing only 2 or 3 fields) but as time went on, I realized that my original assumptions about the data were wrong and my primary keys were not as unique as I thought they were, so I have slowly been expanding them to contain more and more fields. In fact, I have recently come to believe that their database has no constraints whatsoever. Just today, I have finally expanded my a primary key for one of my tables to contain every field in that table and I thought now would be a good time to ask: is it better to add an auto-incrementing column that is just a unique id or just leave a composite primary key on the entire table?

    Read the article

  • Unique visitor counting in ASP.NET MVC

    - by Max
    I'd like to do visitor tracking similar to how stackoverflow does it.. By reading through numerous posts, I've figured out some details already: Count only 1 IP hit per 15 minutes (if anonymous) Count only 1 unique user-Login (per day?) Now that leaves the question of the real implementation.. Should I log the two factors live into a table (and increase count) | IP | timestamp | pageurl | Or do the counting AFTERWARDS (e.g. using IIS log files - which don't include the user, right? I know there're some similar posts outside, but NONE really has a great solution in my opinion yet..

    Read the article

  • What is the fastest language? [closed]

    - by Murtez
    I'm looking to make a site with a database, user accounts, and possibly more later on (subscriptions, bidding, payment, any any possible # of upgrades). Website speed is VERY important, what is the fastest secure language / method to make it in?

    Read the article

  • C#. Where struct methods code kept in memory?

    - by maxima120
    It is somewhat known where .NET keeps value types in memory (mostly in stack but could be in heap in certain circumstances etc)... My question is - where is the code of the struct? If I have say 16 byte of data fields in the struct and a massive computation method in it - I am presuming that 16 byte will be copied in stack and the method code is stored somewhere else and is shared for all instances of the struct. Are these presumptions correct?

    Read the article

  • When to use basic types (Integer, String), and when to write a new class?

    - by belgarat
    Stackoverflow users: A lot of things can be represented in programs by using the basic types, or we can create a new class for it. Example: A social security number can be a number, string or its own object. (Other common examples: Phone numbers, names, zip codes, user id, order id and other id's.) My question is: When should the basic types be used, and when should we write ourselves a new class? I see that when you need to add behavior, you'll want to create a class (example, social security number parsing, validation, formatting, etc). But is this the only criteria? I have come across cases where many of these things are represented as java Integers and/or Strings. We loose the benefit of type-checking, and I have often seen bugs caused by parameters being mixed in calls to function(Intever, Integer, Integer, Integer). On the other hand, some programmers are opposed to over-designing by creating classes for "eveything". Obviously, the answer is "it depends". But, what do you think, and what do you normally do?

    Read the article

  • Explaining your system to a client

    - by Sir Graystar
    I'm currently developing a small Database Management System for a local company. How would you go about explaining how the system you have designed to a client? If they are non-technical and have no understanding of programming, how would you go about showing what the system will do and how it will do it? I guess some sort of visual representation of the system but this seems very patronising to me.

    Read the article

  • What to do when using Contract.Assert(true) and the method must return something?

    - by devoured elysium
    I have a bit of code with the following logic: //pseudo-code foreach (element in elementList) { if (element is whatever) return element; } } In theory, there is always one element that is whatever, so this method should pose no problems. In any case, I've put an assertion on the end of the method just to be sure: //pseudo-code foreach (element in elementList) { if (element is whatever) return element; } } Contract.Assert(true, "Invalid state!"); The problem is that as this method has to return something, and the compiler doesn't understand that the assertion will break the program execution. Before using Contracts, in these kind of situations, I used to throw an Exception, which solved the problem. How would you handle this with Contract.Assert()? Returning null or default(element_type) after the Contract.Assert() call knowing it will never be called and shutting up the compiler? Or is there any other more elegant way of doing this? Thanks

    Read the article

  • db optimization - have a total field or query table?

    - by Dorian Fife
    I have an app where users get points for actions they perform - either 1 point for an easy action or 2 for a difficult one. I wish to display to the user the total number of points he got in my app and the points obtained this week (since Monday at midnight). I have a table that records all actions, along with their time and number of points. I have two alternatives and I'm not sure which is better: Every time the user sees the report perform a query and sum the points the user got Add two fields to each user that records the number of points obtained so far (total and weekly). The weekly points value will be set to 0 every Monday at midnight. The first option is easier, but I'm afraid that as I'll get many users and actions queries will take a long time. The second option bares the risk of inconsistency between the table of actions and the summary values. I'm very interested in what you think is the best alternative here. Thanks, Dorian

    Read the article

  • Tool to maintain a Data Mapping between two systems

    - by ktaylorjohn
    We have XML interfaces between multiple systems. An Enterprise Domain Model is missing in the overall architecture, hence the terms Product/Customer/User means different things to different systems. We currently use excel sheets to map the elements in incoming XML to what the actual Field means within our system. Additionally, it contains the values of Mandatory/Optional and length of each field. We call this the Data Dictionary. Any changes to the XML go through rounds of deliberation and updates to Word and Excel documents. Is there a better way to do this? Any tool/GUI based approach which all systems and owners can view?

    Read the article

  • How value objects are saving and loading?

    - by yeraycaballero
    Since there isn't respositories for value objects. How can I load all value objects? Suppose we are modeling a blog application and we have this classes: Post (Entity) Comment (Value object) Tag (Value object) PostsRespository (Respository) I Know that when I save a new post, its tags are saving with it in the same table. But how could I load all tags of all posts. Has PostsRespository got a method to load all tags? I usually do it, but I want to know others opinions

    Read the article

  • Mocking a namespace in a partial class.

    - by Nix
    I am messing around with Entity Framework 3.5 SP1 and I am trying to find a cleaner way to do the below. Basically I have an EF model and I am adding some Eager Loaded entities and i want to put them in the partial class context Eager namespace. Currently I am using composition but I feel like there is an easier way to do what I want. namespace Entities{ public partial class TestObjectContext { EagerExtensions Eager { get;set;} public TestObjectContext(){ Eager = new EagerExtensions (this); } } public partial class EagerExtensions { TestObjectContext context; public EagerExtensions(TestObjectContext _context){ context = _context; } public IQueryable<TestEntity> TestEntity { get { return context.TestEntity .Include("TestEntityType") .Include("Test.Attached.AttachedType") .AsQueryable(); } } } } public class Tester{ public void ShowHowIWantIt(){ TestObjectContext context= new TestObjectContext(); var query = from a in context.Eager.TestEntity select a; } }

    Read the article

  • how to store data with many categories and many properties efficiently?

    - by Mickey Shine
    We have a large number of data in many categories with many properties, e.g. category 1: Book properties: BookID, BookName, BookType, BookAuthor, BookPrice category 2: Fruit properties: FruitID, FruitName, FruitShape, FruitColor, FruitPrice We have many categories like book and fruit. Obviously we can create many tables for them (MySQL e.g.), and each category a table. But this will have to create too many tables and we have to write many "adapters" to unify manipulating data. The difficulties are: 1) Every category has different properties and this results in a different data structure. 2) The properties of every categoriy may have to be changed at anytime. 3) Hard to manipulate data if each category a table (too many tables) How do you store such kind of data?

    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 | 375 376 377 378 379 380 381 382 383 384 385 386  | Next Page >