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  • Why are controls within custom panel (C# winforms) disappearing in designer?

    - by Brandon
    I have been able to create a custom C# winforms control that is basically a panel with a fixed banner (header/footer). I want to base other user controls on this "banner panel". I've gotten past the problem with the designer here. I can successfully add controls to the inner content panel. Everything looks fine while designing. However, when I recompile, the controls I added to the content panel disappear. They are still there (in code) but aren't displayed in the designer. Is there any thing that I need to do to set the drawing order of the controls?

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  • Best datastructure for this relationship...

    - by Travis
    I have a question about database 'style'. I need a method of storing user accounts. Some users "own" other user accounts (sub-accounts). However not all user accounts are owned, just some. Is it best to represent this using a table structure like so... TABLE accounts ( ID ownerID -> ID name ) ...even though there will be some NULL values in the ownerID column for accounts that do not have an owner. Or would it be stylistically preferable to have two tables, like so. TABLE accounts ( ID name ) TABLE ownedAccounts ( accountID -> accounts(ID) ownerID -> accounts(ID) ) Thanks for the advice.

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  • Bad idea to have the same object, have a different side effect after method call.

    - by Nathan W
    Hi all, I'm having a bit of a gesign issue(again). Say I have this Buttonpad object: now this object is a wrapper object over one in a com object. At the moment it has a method on it called CreateInto(IComObject). Now to make a new button pad in the Com Object. You do: ButtonPad pad = new ButtonPad(); pad.Title = "Hello"; // Set some more properties. pad.CreateInto(Cominstance); The createinfo method will excute the right commands to buid the button pad in the com object. After it has been created it any calls against it are foward to the underlying object for change so: pad.Title = "New title"; will call the com object to set the title and also set the internal title variable. Basically any calls before the CreateInfo method only affect the .NET object anything after has the side effect of calling the com object also. I'm not very good at sequence diagrams but here is my attempt to explain whats going on: This doesn't feel good to me, it feels like I'm lying to the user about what the button pad does. I was going to have a object called WrappedButtonPad, which is returned from CreateInto and the user could make calls against that to make changes to the Com Object, but I feel having two objects that almost do the same thing but only differ by names might be even worse. Are these valid designs, or am I right to be worried? How else would you handle a object the can create and query a com object?

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  • How to update SQL Server database from multiple data sources for ASP.Net MVC 4 application

    - by shaz
    I have 10+ SQL Server databases, from where I would use one table from each database to display information using the application that I am creating. For instance, DB1, DB2....DB10. NewDB (Account, Country, Costcenter....etc.). I have started with creating a new database which would contain all the information from all those 10+ databases. However, I am confused in many cases. First of all what process should I follow? Shall I create a table (in new database) with the same structure as the actual data source and insert data from actual data source to new database? Should I be doing this on the DBMS? If so, is it some scripting? (hint expected since very new to this) I am creating a report generation application which has 10+ data sources. I need some hint which way should I proceed? Thanks for advice/help in advance.

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  • What would be the best schema to store the 'address' for different entities?

    - by Cesar
    Suppose we're making a system where we have to store the addrees for buildings, persons, cars, etc. The address 'format' should be something like: State (From a State list) County (From a County List) Street (free text, like '5th Avenue') Number (free text, like 'Chrysler Building, Floor 10, Office No. 10') (Yes I don't live in U.S.A) What would be the best way to store that info: Should I have a Person_Address, Car_Address, ... Or the address info should be in columns on each entity, Could we have just one address table and try to link each row to a different entity? Or are there another 'better' way to handle this type of scenario? How would yo do it?

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  • Find a regular expression that matches a string?

    - by Mirai
    I need a model for finding all of the regular expressions that would match a particular string. Basically, I need an algorithm for doing what I do to generate a regex search string from some pattern. My purpose for this to create a list of potential regular expressions from a selection of text and order that list from least specific (i.e. string of characters with abitrary length) to most specific (i.e. the string itself) to be used in text editor.

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  • database modeling for google app engine for multiple revison of entity.

    - by iamgopal
    hi, in my application ( kind of wiki clone ) - an article is frequently changing. and i need to track all changes that are done on that article. { text only. } one crude way i have done it, is to add a datetime property and create a new entity everytime something change. which is too much database wasting. { and also un-necessary index waste too. } and also need to re-create parent-child and entity relationships. i also have log which can show changes -- but i want some thing easier , so that jumping from one version to another version could be easier. ideas ? thanks.

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  • How would you structure your entity model for storing arbitrary key/value data with different data t

    - by Nathan Ridley
    I keep coming across scenarios where it will be useful to store a set of arbitrary data in a table using a per-row key/value model, rather than a rigid column/field model. The problem is, I want to store the values with their correct data type rather than converting everything to a string. This means I have to choose either a single table with multiple nullable columns, one for each data type, or a set of value tables, one for each data type. I'm also unsure as to whether I should use full third normal form and separate the keys into a separate table, referencing them via a foreign key from the value table(s), or if it would be better to keep things simple and store the string keys in the value table(s) and accept the duplication of strings. Old/bad: This solution makes adding additional values a pain in a fluid environment because the table needs to be modified regularly. MyTable ============================ ID Key1 Key2 Key3 int int string date ---------------------------- 1 Value1 Value2 Value3 2 Value4 Value5 Value6 Single Table Solution This solution allows simplicity via a single table. The querying code still needs to check for nulls to determine which data type the field is storing. A check constraint is probably also required to ensure only one of the value fields contains non-nulll data. DataValues ============================================================= ID RecordID Key IntValue StringValue DateValue int int string int string date ------------------------------------------------------------- 1 1 Key1 Value1 NULL NULL 2 1 Key2 NULL Value2 NULL 3 1 Key3 NULL NULL Value3 4 2 Key1 Value4 NULL NULL 5 2 Key2 NULL Value5 NULL 6 2 Key3 NULL NULL Value6 Multiple-Table Solution This solution allows for more concise purposing of each table, though the code needs to know the data type in advance as it needs to query a different table for each data type. Indexing is probably simpler and more efficient because there are less columns that need indexing. IntegerValues =============================== ID RecordID Key Value int int string int ------------------------------- 1 1 Key1 Value1 2 2 Key1 Value4 StringValues =============================== ID RecordID Key Value int int string string ------------------------------- 1 1 Key2 Value2 2 2 Key2 Value5 DateValues =============================== ID RecordID Key Value int int string date ------------------------------- 1 1 Key3 Value3 2 2 Key3 Value6 How do you approach this problem? Which solution is better? Also, should the key column be separated into a separate table and referenced via a foreign key or be should it be kept in the value table and bulk updated if for some reason the key name changes?

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  • 0/1 Knapsack with irrational weights

    - by user356106
    Consider the 0/1 knapsack problem. The standard Dynamic Programming algorithm applies only when the capacity as well as the weights to fill the knapsack with are integers/ rational numbers. What do you do when the capacity/weights are irrational? The issue is that we can't memoize like we do for integer weights because we may need potentially infinite decimal places for irrational weights - leading to an infinitely large number of columns for the Dynamic Programming Table . Is there any standard method for solving this? Any comments on the complexity of this problem? Any heuristics? What about associated recurrences like (for example): f(x)=1, for x< sqrt(2) f(x)=f(x-sqrt(2))+sqrt(3)

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  • Re-usable Obj-C classes with custom values: The right way

    - by Prairiedogg
    I'm trying to reuse a group of Obj-C clases between iPhone applications. The values that differ from app to app have been isolated and I'm trying to figure out the best way to apply these custom values to the classes on an app-to-app basis. Should I hold them in code? // I might have 10 customizable values for each class, that's a long signature! CarController *controller = [[CarController alloc] initWithFontName:@"Vroom" engine:@"Diesel" color:@"Red" number:11]; Should I store them in a big settings.plist? // Wasteful! I sometimes only use 2-3 of 50 settings! AllMyAppSettings *settings = [[AllMyAppSettings alloc] initFromDisk:@"settings.plist"]; MyCustomController *controller = [[MyCustomController alloc] initWithSettings:settings]; [settings release]; Should I have little, optional n_settings.plists for each class? // Sometimes I customize CarControllerSettings *carSettings = [[CarControllerSettings alloc] initFromDisk:@"car_settings.plist"]; CarController *controller = [[CarController alloc] initWithSettings:carSettings]; [carSettings release]; // Sometimes I don't, and CarController falls back to internally stored, reasonable defaults. CarController *controller = [[CarController alloc] initWithSettings:nil]; Or is there an OO solution that I'm not thinking of at all that would be better?

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  • How to choose between UUIDs, autoincrement/sequence keys and sequence tables for database primary keys?

    - by Tim
    I'm looking at the pros and cons of these three primary methods of coming up with primary keys for database rows. So assuming I am using a database that supports more than one of these methods, is there a simple heuristic to determine what the best option would be for me? How do considerations such a distributed/multiple masters, performance requirements, ORM use, security and testing have on the choice? Any unexpected drawbacks that one might run into?

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  • Better alternative to autonumber primary keys

    - by Comrad_Durandal
    I am looking for a better primary key than the autonumber data type, namely for the reason that it's limited to a long integer, when I really just need the field to reflect a number or text string that will never ever repeat, no matter HOW many records are added or deleted from the table. The problem is I am not sure how to implement something like turning the current date and time into a hexadecimal string and using that as a unique field I can use as a primary key. Am I just being too paranoid about running out of space?

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  • How can several different datatypes be saved in one table

    - by poseidon
    This is my situation: I am constructing an ad-like application in Django and Mysql. I am using a flexible-ad approach where we have: a table with ad categories (several categories such as home, furniture, cars, etc.) id_category name a table with details for the ad categories (home: area, squared meters. car: seats, color.) id_detail id_category (the categ the detail describes) name type (boolean, char, int, long, etc.) the ad table (i am selling a house. i am selling a car.) id_ad id_category text date a table where i plan to consolidate the details of the ads (home: A-area, 500 sq-meters. car: 5 seats, red.) id_detail_ad id_ad id_detail value Is this possible? Can I have a table of details for all the ads, even if details include numbers, texts, booleans, etc? Or would I have to save them all as text and then interpret them via code accordingly? Please express your opinions. Thank you.

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  • Determining Best Table Structure for MySQL Performance

    - by Joe Majewski
    I'm working on a browser-based RPG for one of my websites, and right now I'm trying to determine the best way to organize my SQL tables for performance and maintenance. Here's my question: Does the number of columns in an SQL table affect the speed in which it can be queried? I am not a newbie when it comes to PHP or MySQL. I used to develop things with the common goal of getting them to work, but I've recently advanced to the stage where a functional program is not good enough unless it's fast and reliable. Anyways, right now I have a members table that has around 15 columns. It contains information such as the player's username, password, email, logins, page views, etcetera. It doesn't contain any information on the player's progress in the game, however. If I added columns for things such as army size, gold, turns, and whatnot, then it could easily rise to around 40 or 50 total columns. Oh, and my database structure IS normalized. Will a table with 50 columns that gets constantly queried be a bad idea? Should I split it into two tables; one for the user's general information and one for the user's game statistics? I know I could check the query time myself, but I haven't actually created the tables yet and I think I'd be better off with some professional advice on this important decision for my game. Thank you for your time! :)

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  • PHP string to object name.

    - by Smickie
    Ok I have a string... $a_string = "Product"; and I want to use this string in a call to a object like this: $this->$a_string->some_function(); How the dickens do I dynamically call that object? (don't think Im on php 5 mind)

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  • Why does std::map operator[] create an object if the key doesn't exist?

    - by n1ck
    Hi, I'm pretty sure I already saw this question somewhere (comp.lang.c++? Google doesn't seem to find it there either) but a quick search here doesn't seem to find it so here it is: Why does the std::map operator[] create an object if the key doesn't exist? I don't know but for me this seems counter-intuitive if you compare to most other operator[] (like std::vector) where if you use it you must be sure that the index exists. I'm wondering what's the rationale for implementing this behavior in std::map. Like I said wouldn't it be more intuitive to act more like an index in a vector and crash (well undefined behavior I guess) when accessed with an invalid key? Refining my question after seeing the answers: Ok so far I got a lot of answers saying basically it's cheap so why not or things similar. I totally agree with that but why not use a dedicated function for that (I think one of the comment said that in java there is no operator[] and the function is called put)? My point is why doesn't map operator[] work like a vector? If I use operator[] on an out of range index on a vector I wouldn't like it to insert an element even if it was cheap because that probably mean an error in my code. My point is why isn't it the same thing with map. I mean, for me, using operator[] on a map would mean: i know this key already exist (for whatever reason, i just inserted it, I have redundancy somewhere, whatever). I think it would be more intuitive that way. That said what are the advantage of doing the current behavior with operator[] (and only for that, I agree that a function with the current behavior should be there, just not operator[])? Maybe it give clearer code that way? I don't know. Another answer was that it already existed that way so why not keep it but then, probably when they (the ones before stl) choose to implement it that way they found it provided an advantage or something? So my question is basically: why choose to implement it that way, meaning a somewhat lack of consistency with other operator[]. What benefit do it give? Thanks

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  • How to create a generic method in C# that's all applicable to many types - ints, strings, doubles et

    - by satyajit
    Let's I have a method to remove duplicates in an integer Array public int[] RemoveDuplicates(int[] elems) { HashSet<int> uniques = new HashSet<int>(); foreach (int item in elems) uniques.Add(item); elems = new int[uniques.Count]; int cnt = 0; foreach (var item in uniques) elems[cnt++] = item; return elems; } How can I make this generic such that now it accepts a string array and remove duplicates in it? How about a double array? I know I am probably mixing things here in between primitive and value types. For your reference the following code won't compile public List<T> RemoveDuplicates(List<T> elems) { HashSet<T> uniques = new HashSet<T>(); foreach (var item in elems) uniques.Add(item); elems = new List<T>(); int cnt = 0; foreach (var item in uniques) elems[cnt++] = item; return elems; } The reason is that all generic types should be closed at run time. Thanks for you comments

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  • Does OOP make sense for small scripts?

    - by Fabian
    I mostly write small scripts in python, about 50 - 250 lines of code. I usually don't use any objects, just straightforward procedural programming. I know OOP basics and I have used object in other programming languages before, but for small scripts I don't see how objects would improve them. But maybe that is just my limited experience with OOP. Am I missing something by not trying harder to use objects, or does OOP just not make a lot of sense for small scripts?

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  • How many databases to support eCommerce?

    - by Terry Lorber
    I have a system with two databases, one that the customer-facing website uses, the second that is used by the "backroom" order-fulfillment system. I've been asked to run queries from the website to the backroom system. I'd rather not, it seems risky to allow web-based request to run unheeded on the internal system. Additionally, this means opening up routing in the firewall to allow external connections to the internal server. What's the best practice for eCommerce? Run the entire company off of one database? Or individual databases for each system, and middleware to connect them? Sometimes it might be necessary for the web application to pull date from the internal system, but not based on an HTTP request from the internet. I'm sure the best answer is "it depends!" So, if people have a rule of thumb for when to use middleware and when not to, I'd like to here it.

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  • Unable to find the cause of an annoying content gap in my HTML/CSS?

    - by user1472747
    I'm quite new to CSS / HTML, and can't find the cause of this little bugger. I want it gone, so that the banner and the nav bar touch each other. Any help is greatly appreciated!! Here is the code for the site. I took out some of the irrelevant code. <!DOCTYPE html> <html> <!-- *****CSS CODE START*****--> <style type="text/css"> #container { margin: 0 auto; width: 900px; background: #fff; } #header { margin-top: 0px; } #header h1 { margin: 0; } #navigation { float: left; width: 900px; background: #333; } #navigation ul { margin: 0; padding: 0; } #navigation ul li { list-style-type: none; display: inline; } #navigation li a { display: block; float: left; padding: 5px 10px; color: #fff; text-decoration: none; border-right: 1px solid #fff; } #navigation li a:hover { background: #383; } #content-container { float: left; width: 900px; background: #fff url(/wp-content/uploads/layout-two-fixed-background.gif) repeat-y 100% 0; } #content { clear: left; float: left; width: 619px; height: 720px; padding: 10px 0; margin: 0 0 0 0px; display: inline; overflow: auto; } #content h2 { margin: 0; color: #003D5D; padding:10px; } #contentBody { padding:10px; font-size:22px; } #aside { float: right; width: 280px; padding: 20px 0; margin: 0 0px 0 0; display: inline; background: #cccccc; height: 700px; border-left: 1px solid #333 ; } #aside h3 { margin: 0 20px; color: #003D5D; font-family: Times New Roman; } #asideText { margin: 0 20px; font-family: Times New Roman;} #footer { clear: both; background: #ccc; text-align: right; padding: 5px; height: 1%; border-top: 1px solid #333 ; } </style> <!-- *****CSS CODE END***** --> <!-- *****HTML CODE START***** --> <body> <div id="container"> <div id="header"> <img src = file:///Users/jduffy/Desktop/projectSite/banner1.jpg> </img> </div> <div id="navigation"> <ul> <li><a href="file:///Users/jduffy/Desktop/projectSite/home">Home</a></li> <li><a href="file:///Users/jduffy/Desktop/projectSite/theProject">The Project</a></li> <li><a href="file:///Users/jduffy/Desktop/projectSite/Pictures">Pictures</a></li> <li><a href="file:///Users/jduffy/Desktop/projectSite/Contact">Contact us</a></li> </ul> </div> <div id="content-container"> <div id="content"> <h2> Page heading </h2> <div id="contentBody"> <p> home pagehome pagehome pagehome pagehome pagehome pagehome pagehome pagehome pagehome pagehome pagehome page home pagehome pagehome pagehome pagehome pagehome pagehome pagehome pagehome pagehome pagehome pagehome page home pagehome pagehome pagehome pagehome pagehome pagehome pagehome pagehome pagehome pagehome pagehome page </p> <p> test2 </p> <p> test3 </p> </div> </div> <div id="aside"> <div id="asideHeading"> <h3> Aside Heading </h3> </div> <div id="asideText"> <p> test5 </p> </div> </div> <div id="footer"> <text id="footerDate">0</text> </div> </div> </div> </body> <!-- *****HTML CODE END***** --> </html> <!-- *****JavaScript CODE START***** --> <script type="text/javascript"> /*date*/ var today = new Date(); document.getElementById("footerDate").innerHTML = today; </script> <!-- *****JavaScript CODE END***** -->

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