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  • R concentrating data frame

    - by user1631503
    I have a data frame like this >X_com Day_1 Day_2 Day_3 Day_4 Day_5 Day_6 Day_7 Day_8 Day_9 Day_10 1 0 0 0 0 0 0 0 0 0 1 2 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 5 0 0 0 0 0 0 0 0 0 0 6 0 0 0 0 0 0 0 0 0 0 7 0 0 0 0 0 0 0 0 0 0 8 0 0 0 0 0 0 0 0 0 0 I need to concentrate all the values into one column and add another column with "1;" So I did this > X_new=matrix(1,8,2) > X_new[1,]=paste(X_com[1,1], X_com[1,2],X_com[1,3],X_com [1,4],X_com[1,5],X_com[1,6],X_com[1,7],X_com[1,8],X_com [1,9],X_com[1,10], sep="") > X_new[2,]=paste(X_com[2,1], X_com[2,2],X_com[2,3],X_com [2,4],X_com[2,5],X_com[2,6],X_com[2,7],X_com[2,8],X_com [2,9],X_com[2,10], sep="") > X_new[3,]=paste(X_com[3,1], X_com[3,2],X_com[3,3],X_com [3,4],X_com[3,5],X_com[3,6],X_com[3,7],X_com[3,8],X_com [3,9],X_com[3,10], sep="") > X_new[4,]=paste(X_com[4,1], X_com[4,2],X_com[4,3],X_com [4,4],X_com[4,5],X_com[4,6],X_com[4,7],X_com[4,8],X_com [4,9],X_com[4,10], sep="") > X_new[5,]=paste(X_com[5,1], X_com[5,2],X_com[5,3],X_com [5,4],X_com[5,5],X_com[5,6],X_com[5,7],X_com[5,8],X_com [5,9],X_com[5,10], sep="") > X_new[6,]=paste(X_com[6,1], X_com[6,2],X_com[6,3],X_com [6,4],X_com[6,5],X_com[6,6],X_com[6,7],X_com[6,8],X_com [6,9],X_com[6,10], sep="") > X_new[7,]=paste(X_com[7,1], X_com[7,2],X_com[7,3],X_com [7,4],X_com[7,5],X_com[7,6],X_com[7,7],X_com[7,8],X_com [7,9],X_com[7,10], sep="") > X_new[8,]=paste(X_com[8,1], X_com[8,2],X_com[8,3],X_com [8,4],X_com[8,5],X_com[8,6],X_com[8,7],X_com[8,8],X_com [8,9],X_com[8,10], sep="") > X_new[1:8,2]="1;" > as.data.frame(X_new) V1 V2 1 0000000001 1; 2 0000000000 1; 3 0000000000 1; 4 0000000000 1; 5 0000000000 1; 6 0000000000 1; 7 0000000000 1; 8 0000000000 1; I believe there's definitely a faster way of achieving this but have no clue. The other problem is, I have over a thousand of data frame like this needs to be concentrated. I'm still learning how to loop these repetitive steps but is progressing quite slowly. If the original data frames were named uniquely, does that mean I have no choice but to work on each of them individually? Thank you in advance.

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  • Java: immutability, overuse of stack -- better data structure?

    - by HH
    I overused hashSets but it was slow, then changed to Stacks, speed boost-up. Poly's reply uses Collections.emptyList() as immutable list, cutting out excess null-checkers. No Collections.emptyStack(). Combining the words stack and immutability, from the last experiences, gets "immutable stack" (probably not related to functional prog). Java Api 5 for list interface shows that Stack is an implementing class for list and arraylist, here. The java.coccurrent pkg does not have any immutable Stack data structure. The first hinted of misusing stack. The lack of immutabily in the last and poly's book recommendation leads way to list. Something very primitive, fast, no extra layers, with methods like emptyThing(). Overuse of stack and where I use it DataFile.java: public Stack<DataFile> files; FileObject.java: public Stack<String> printViews = new Stack<String>(); FileObject.java:// private static Stack<Object> getFormat(File f){return (new Format(f)).getFormat();} Format.java: private Stack<Object> getLine(File[] fs,String s){return wF;} Format.java: private Stack<Object> getFormat(){return format;} Positions.java: public static Stack<Integer[]> getPrintPoss(String s,File f,Integer maxViewPerF) Positions.java: Stack<File> possPrint = new Stack<File>(); Positions.java: Stack<Integer> positions=new Stack<Integer>(); Record.java: private String getFormatLine(Stack<Object> st) Record.java: Stack<String> lines=new Stack<String>(); SearchToUser.java: public static final Stack<File> allFiles = findf.getFs(); SearchToUser.java: public static final Stack<File> allDirs = findf.getDs(); SearchToUser.java: private Stack<Integer[]> positionsPrint=new Stack<Integer[]>(); SearchToUser.java: public Stack<String> getSearchResults(String s, Integer countPerFile, Integer resCount) SearchToUser.java: Stack<File> filesToS=Fs2Word.getFs2W(s,50); SearchToUser.java: Stack<String> rs=new Stack<String>(); View.java: public Stack<Integer[]> poss = new Stack<Integer[4]>(); View.java: public static Stack<String> getPrintViewsFileWise(String s,Object[] df,Integer maxViewsPerF) View.java: Stack<String> substrings = new Stack<String>(); View.java: private Stack<String> printViews=new Stack<String>(); View.java: MatchView(Stack<Integer> pss,File f,Integer maxViews) View.java: Stack<String> formatFile; View.java: private Stack<Search> files; View.java: private Stack<File> matchingFiles; View.java: private Stack<String> matchViews; View.java: private Stack<String> searchMatches; View.java: private Stack<String> getSearchResults(Integer numbResults) Easier with List: AllDirs and AllFs, now looping with push, but list has more pow. methods such as addAll [OLD] From Stack to some immutable data structure How to get immutable Stack data structure? Can I box it with list? Should I switch my current implementatios from stacks to Lists to get immutable? Which immutable data structure is Very fast with about similar exec time as Stack? No immutability to Stack with Final import java.io.*; import java.util.*; public class TestStack{ public static void main(String[] args) { final Stack<Integer> test = new Stack<Integer>(); Stack<Integer> test2 = new Stack<Integer>(); test.push(37707); test2.push(80437707); //WHY is there not an error to remove an elment // from FINAL stack? System.out.println(test.pop()); System.out.println(test2.pop()); } }

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  • iPhone - Core Data crash on migration

    - by Sergey Zenchenko
    I have problems, when i install app from Xcode all works but if I build app and install it from iTunes I have an error with the database at launch. This happens only than i have changes in the core data model and need to migrate to a new version. At first launch at crashes with message: Thread 0: 0 libSystem.B.dylib 0x00034588 pwrite + 20 1 libsqlite3.dylib 0x000505ec _sqlite3_purgeEligiblePagerCacheMemory + 2808 2 libsqlite3.dylib 0x000243d8 sqlite3_backup_init + 7712 3 libsqlite3.dylib 0x000244ac sqlite3_backup_init + 7924 4 libsqlite3.dylib 0x0000d418 sqlite3_file_control + 4028 5 libsqlite3.dylib 0x000228b4 sqlite3_backup_init + 764 6 libsqlite3.dylib 0x00022dd0 sqlite3_backup_init + 2072 7 libsqlite3.dylib 0x000249a8 sqlite3_backup_init + 9200 8 libsqlite3.dylib 0x00029800 sqlite3_open16 + 11360 9 libsqlite3.dylib 0x0002a200 sqlite3_open16 + 13920 10 libsqlite3.dylib 0x0002ab84 sqlite3_open16 + 16356 11 libsqlite3.dylib 0x00049418 sqlite3_prepare16 + 54056 12 libsqlite3.dylib 0x00002940 sqlite3_step + 44 13 CoreData 0x00011958 _execute + 44 14 CoreData 0x000113e0 -[NSSQLiteConnection execute] + 696 15 CoreData 0x000994be -[NSSQLConnection prepareAndExecuteSQLStatement:] + 26 16 CoreData 0x000be14c -[_NSSQLiteStoreMigrator performMigration:] + 244 17 CoreData 0x000b6c60 -[NSSQLiteInPlaceMigrationManager migrateStoreFromURL:type:options:withMappingModel:toDestinationURL:destinationType:destinationOptions:error:] + 1040 18 CoreData 0x000aceb0 -[NSStoreMigrationPolicy(InternalMethods) migrateStoreAtURL:toURL:storeType:options:withManager:error:] + 92 19 CoreData 0x000ad6f0 -[NSStoreMigrationPolicy migrateStoreAtURL:withManager:metadata:options:error:] + 72 20 CoreData 0x000ac9ee -[NSStoreMigrationPolicy(InternalMethods) _gatherDataAndPerformMigration:] + 880 21 CoreData 0x0000965c -[NSPersistentStoreCoordinator addPersistentStoreWithType:configuration:URL:options:error:] + 1328 At next launches app doesn't loads data from database.

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  • WCF Data Service Exception

    - by Ravi
    Hi, I am working on C#.Net with ADO.NET Dataservice WCF Data Services. I try to update one record to relational table, when I reach context.SetLink() I am getting exception("The context is not currently tracking the entity"). I don't know how to solve this problem. My code is specified below. LogNote dbLogNote =logNote; LogSubSession dbLogSubSession = (from p in context.LogSubSession where p.UID == logNote.SubSessionId select p).First<LogSubSession>() as LogSubSession; context.AddToLogNote(dbLogNote); dbLogNote.LogSubSession = dbLogSubSession; context.SetLink(dbLogNote, "LogSubSession", dbLogSubSession); context.SaveChanges(); Here LogSubSession is a primary table and LogNote is a foreign table. I am updating data into foreign table based on primary key table. Thanks

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  • C# System.Data.SQLite Designer Code

    - by Nathan
    I've been messing around with the SQLite Designer in Visual Studio 2008 and I have noticed that when I use the generated Insert/Update statements they run extremely slow. Example: I have a data table with four columns and 5700 rows it took ~5 mins to insert the data into the database table However, I wrote my own database connection and insert methods using parameters and a single transaction and the same 5700 rows were inserted in under 1 second. Why is the generated code so slow and what is benefit to even using it? Thanks. Nathan

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  • Core Data Error "Fetch Request must have an entity"

    - by Graeme
    Hi, I've attempted to add the TopSongs parser and Core Data files into my application, and it now builds succesfully, with no errors or warning messages. However, as soon as the app loads, it crashes, giving the following reason: *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: 'executeFetchRequest:error: A fetch request must have an entity.' I have renamed all files, including the .xcdatamodel file. Could this be the problem (the renaming of the .xcdatamodel)? I'm assuming this error means that no data can be found. Thanks.

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  • WCF REST vs. ADO.NET Data Services

    - by ray247
    Hi there, Could someone compare and contrast on WCF Rest services vs. ADO.NET Data Services? What is the difference and when to use which? Thanks, Ray. Edit: thanks to the first answer, just to give a bit background on what I'm looking to do: I have a web app I plan to put in the cloud (someday), the DAL is built with ADO.NET Entity Framework. And, I need to figure which web service data access technology would best fit my case.

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  • Core Data NSPredicate for relationships.

    - by Mugunth Kumar
    My object graph is simple. I've a feedentry object that stores info about RSS feeds and a relationship called Tag that links to "TagValues" object. Both the relation (to and inverse) are to-many. i.e, a feed can have multiple tags and a tag can be associated to multiple feeds. I referred to http://stackoverflow.com/questions/844162/how-to-do-core-data-queries-through-a-relationship and created a NSFetchRequest. But when fetch data, I get an exception stating, NSInvalidArgumentException unimplemented SQL generation for predicate What should I do? I'm a newbie to core data :( I know I've done something terribly wrong... Please help... Thanks -- NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init]; // Edit the entity name as appropriate. NSEntityDescription *entity = [NSEntityDescription entityForName:@"FeedEntry" inManagedObjectContext:managedObjectContext]; [fetchRequest setEntity:entity]; // Edit the sort key as appropriate. NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"authorname" ascending:NO]; NSArray *sortDescriptors = [[NSArray alloc] initWithObjects:sortDescriptor, nil]; [fetchRequest setSortDescriptors:sortDescriptors]; NSEntityDescription *tagEntity = [NSEntityDescription entityForName:@"TagValues" inManagedObjectContext:self.managedObjectContext]; NSPredicate *tagPredicate = [NSPredicate predicateWithFormat:@"tagName LIKE[c] 'nyt'"]; NSFetchRequest *tagRequest = [[NSFetchRequest alloc] init]; [tagRequest setEntity:tagEntity]; [tagRequest setPredicate:tagPredicate]; NSError *error = nil; NSArray* predicates = [self.managedObjectContext executeFetchRequest:tagRequest error:&error]; TagValues *tv = (TagValues*) [predicates objectAtIndex:0]; NSLog(tv.tagName); // it is nyt here... NSPredicate *predicate = [NSPredicate predicateWithFormat:@"tag IN %@", predicates]; [fetchRequest setPredicate:predicate]; // Edit the section name key path and cache name if appropriate. // nil for section name key path means "no sections". NSFetchedResultsController *aFetchedResultsController = [[NSFetchedResultsController alloc] initWithFetchRequest:fetchRequest managedObjectContext:managedObjectContext sectionNameKeyPath:nil cacheName:@"Root"]; aFetchedResultsController.delegate = self; self.fetchedResultsController = aFetchedResultsController; --

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  • How to invalidate a single data item in the .net cache in VB

    - by Craig
    I have the following .NET VB code to set and read objects in cache on a per user basis (i.e. a bit like session) '' Public Shared Sub CacheSet(ByVal Key As String, ByVal Value As Object) Dim userID As String = HttpContext.Current.User.Identity.Name HttpContext.Current.Cache(Key & "_" & userID) = Value End Sub Public Shared Function CacheGet(ByVal Key As Object) Dim returnData As Object = Nothing Dim userID As String = HttpContext.Current.User.Identity.Name returnData = HttpContext.Current.Cache(Key & "_" & userID) Return returnData End Function I use these functions to hold user data that I don't want to access the DB for all the time. However, when the data is updated, I want the cached item to be removed so it get created again. How do I make an Item I set disappear or set it to NOTHING or NULL? Craig

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  • Request for the permission of type 'System.Data.SqlClient.SqlClientPermission, System.Data

    - by joebeazelman
    I created an assembly containing WCF service code and dropped into another web project. When I try to invoke a service method, I get the following inner exception: Request for the permission of type 'System.Data.SqlClient.SqlClientPermission, System.Data, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed. Why this is happening? My newly created assembly lives inside the ASP.NET /bin folder along with other assemblies. At this level, should the database not know or care whether it is being called from a web service or from a normal call? How would it know that my assembly is foreign? How do I resolve this issue?

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  • Returning to last viewed List page after insert/edit with ASP.NET Dynamic Data

    - by Pat James
    With a pretty standard Dynamic Data site, when the user edits or inserts a new item and saves, the page does a Response.Redirect(table.ListActionPath), which takes the user back to page 1 of the table. If they were editing an item on page 10 (or whatever) and want to edit the next item on that page, they have to remember the page number and navigate back to it. What's the best way to return the user to the list page they last viewed? I can conceive of some solutions using cookies, session state, or query string values to retain this state and making my own Page Template to incorporate it, but I can't help thinking this must be something that was considered when Dynamic Data was created, and there must be something simpler or built-in to the framework that I'm missing here.

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  • Adding rows to UItableview and passing data between Viewcontrollers

    - by Jonathan
    I have a list of websites in a plist, when the app loads this populates a tableview (which is inside a navigation controller) But I have added an add button to the navigation bar and then created another View Controller to deal with inputting of the new website (Like Title and URL). It is very similar to how the contacts app looks. There is a table view and when you tap add, the add UI slides up. I have got all this working great so far. My Problem is what happens when the user taps Done. I can add the website to the plist (each website is a dictionary in the plist with 2 keys, atm) But then how do I tell the tableView to update? The table view has not been removed from the main window, just the add view has been added on top of the "screen". Another way of asking is, when you tap Save on Add a Contact screen: (not my image) How does the new contact's data (Xyz's data) get shown on the tableview?

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  • ASP.NET MVC2 Data Access Layer

    - by Paul
    For a small/medium sized project I'm trying to figure out what is the 'ideal' way to have a domain layer and data access layer. My opinions on coupling tend to be more towards the view that the domain models should not be tightly coupled with the database layer, in other words the data access layer shouldn't actually know anything about the domain objects. I've been looking at Linq-to-sql and it wants to use its own models that it creates, and so it ends up VERY tightly coupled. Whilst I love the way you use linq-to-sql in code I really don't like the way it wants to make its own domain objects. What are some alternatives that I should consider? I tried use NHibernate but I did not like the way I had to use to query and get different objects. I honestly love the syntax and way you use linq, I just don't want it to be so tightly coupled to domain objects.

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  • Core data and special characters (UTF-8)

    - by MW
    I have an iPhone application using Core Data with an SQLite database in the bottom. I'm writing some text content from the database to a file, but special characters such as Å, Ä and Ö are corrupted in the file (they show up just fine in the application). When creating and inserting data, I am not using any special encoding. I'm just taking the NSString (entered by the user in a UITextField) and putting it in my persistent objects. When saving the file, I use the following code: [csvString writeToFile:filePath atomically:YES encoding:NSUTF8StringEncoding error:&error]; I tried adding a BOM to the beginning of the text ("\xef\xbb\xbf") but it is still corrupted. Anyone has any ideas where the problem might be? Examples of corrupted characters: å becomes ö, ä becomes ä

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  • Data structure for Settlers of Catan map?

    - by templatetypedef
    Hello all- A while back someone asked me if I knew of a nice way to encode the information for the game Settlers of Catan. This would require storing a hexagonal grid in a way where each hex can have data associated with it. More importantly, though, I would need some way of efficiently looking up vertices and edges on the sides of these hexagons, since that's where all the action is. My question is this: is there a good, simple data structure for storing a hexagonal grid while allowing for fast lookup of hexagons, edges between hexagons, and vertices at the intersections of hexagons? I know that general structures like a winged-edge or quad-edge could do this, but that seems like massive overkill. Thanks!

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  • Advanced SQL Data Compare throught multiple tables

    - by podosta
    Hello, Consider the situation below. Two tables (A & B), in two environments (DEV & TEST), with records in those tables. If you look the content of the tables, you understand that functionnal data are identical. I mean except the PK and FK values, the name Roger is sill connected to Fruit & Vegetable. In DEV environment : Table A 1 Roger 2 Kevin Table B (italic field is FK to table A) 1 1 Fruit 2 1 Vegetable 3 2 Meat In TEST environment : Table A 4 Roger 5 Kevin Table B (italic field is FK to table A) 7 4 Fruit 8 4 Vegetable 9 5 Meat I'm looking for a SQL Data Compare tool which will tell me there is no difference in the above case. Or if there is, it will generate insert & update scripts with the right order (insert first in A then B) Thanks a lot guys, Grégoire

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  • Modeling distribution of performance measurements

    - by peterchen
    How would you mathematically model the distribution of repeated real life performance measurements - "Real life" meaning you are not just looping over the code in question, but it is just a short snippet within a large application running in a typical user scenario? My experience shows that you usually have a peak around the average execution time that can be modeled adequately with a Gaussian distribution. In addition, there's a "long tail" containing outliers - often with a multiple of the average time. (The behavior is understandable considering the factors contributing to first execution penalty). My goal is to model aggregate values that reasonably reflect this, and can be calculated from aggregate values (like for the Gaussian, calculate mu and sigma from N, sum of values and sum of squares). In other terms, number of repetitions is unlimited, but memory and calculation requirements should be minimized. A normal Gaussian distribution can't model the long tail appropriately and will have the average biased strongly even by a very small percentage of outliers. I am looking for ideas, especially if this has been attempted/analysed before. I've checked various distributions models, and I think I could work out something, but my statistics is rusty and I might end up with an overblown solution. Oh, a complete shrink-wrapped solution would be fine, too ;) Other aspects / ideas: Sometimes you get "two humps" distributions, which would be acceptable in my scenario with a single mu/sigma covering both, but ideally would be identified separately. Extrapolating this, another approach would be a "floating probability density calculation" that uses only a limited buffer and adjusts automatically to the range (due to the long tail, bins may not be spaced evenly) - haven't found anything, but with some assumptions about the distribution it should be possible in principle. Why (since it was asked) - For a complex process we need to make guarantees such as "only 0.1% of runs exceed a limit of 3 seconds, and the average processing time is 2.8 seconds". The performance of an isolated piece of code can be very different from a normal run-time environment involving varying levels of disk and network access, background services, scheduled events that occur within a day, etc. This can be solved trivially by accumulating all data. However, to accumulate this data in production, the data produced needs to be limited. For analysis of isolated pieces of code, a gaussian deviation plus first run penalty is ok. That doesn't work anymore for the distributions found above. [edit] I've already got very good answers (and finally - maybe - some time to work on this). I'm starting a bounty to look for more input / ideas.

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  • How to find out memory layout of your data structure implementation on Linux 64bit machine

    - by ajay
    In this article, http://cacm.acm.org/magazines/2010/7/95061-youre-doing-it-wrong/fulltext the author talks about the memory layouts of 2 data structures - The Binary Heap and the B-Heap and compares how one has better memory layout than the other. http://deliveryimages.acm.org/10.1145/1790000/1785434/figs/f5.jpg http://deliveryimages.acm.org/10.1145/1790000/1785434/figs/f6.jpg I want to get hands on experience on this. I have an implementation of a N-Ary Tree and I want to find out the memory layout of my data structure. What is the best way to come up with a memory layout like the one in the article? Secondly, I think it is easier to identify the memory layout if it is an array based implementation. If the implementation of a Tree uses pointers then what Tools do we have or what kind of approach is required to map it's memory layout? Thanks!

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  • operator not defined for System.Data.SqlClient.SqlConnection and System.Data.SqlClient.SqlConnection

    - by Beta033
    i hope i'm just doing something wrong here. Ideally i'm trying to open the connection, open a transaction execute a ton of prebuilt sqlstatements (with parameters) against this connection then close the connection. ideally all in the same batch. It's easy enough to wrap this all in a for loop, however i'd like to use the forEach function of the list generic to set the connection as it'll probably be faster than my implementation of calling List.Item(i) in the loop but i get some strange errors. Dim sqlStatements As List(Of SqlCommand) = New List(Of SqlCommand) Dim conn As SqlClient.SqlConnection = New SqlConnection("...") sqlStatements.Item(0).Connection = conn 'Works sqlStatements.ForEach(Function(ByRef cmd As SqlCommand) cmd.Connection = conn) 'ERROR: Operator '=' is not defined for types 'System.Data.SqlClient.SqlConnection' 'and 'System.Data.SqlClient.SqlConnection What does this error really mean?

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  • Silverlight 4 accessing WCF Data Services: BeginInvoke frustrations.

    - by Gatmando
    Hi, I'm attempting to follow a pattern for performing WCF data service queries using the Silverlight 4 beta. The following is my code: public CodeTables() { CodeCountries = new ObservableCollection<dsRealHomes.CodeCountries>(); dsRealHomes.RealHomesEntities myClient = null; myClient = staticGlobals.RealHomesContext(); object userState = null; myClient.BeginExecute<dsRealHomes.CodeCountries>(new Uri("CodeCountries"), (IAsyncResult asyncResult) => { Dispatcher.BeginInvoke( () => { var test = myClient.EndExecute<dsRealHomes.CodeCountries>asyncResult).ToList(); } ); }, userState); } This is derived from a number of examples I've come across for WCF data services with silverlight. Unfortunately no matter how I try to implement the code i end up with the following error on 'Dispatcher.BeginInvoke': 'An object reference is required for the non-static field, method, or property (System.Windows.Threading.Dispatcher.BeginInvoke(System.Action)' Thanks

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  • Counting number of children in hierarchical SQL data

    - by moontear
    Hello, for a simple data structure such as so: ID parentID Text Price 1 Root 2 1 Flowers 3 1 Electro 4 2 Rose 10 5 2 Violet 5 6 4 Red Rose 12 7 3 Television 100 8 3 Radio 70 9 8 Webradio 90 For reference, the hierarchy tree looks like this: ID Text Price 1 Root |2 Flowers |-4 Rose 10 | |-6 Red Rose 12 |-5 Violet 5 |3 Electro |-7 Television 100 |-8 Radio 70 |-9 Webradio 90 I'd like to count the number of children per level. So I would get a new column "NoOfChildren" like so: ID parentID Text Price NoOfChildren 1 Root 8 2 1 Flowers 3 3 1 Electro 3 4 2 Rose 10 1 5 2 Violet 5 0 6 4 Red Rose 12 0 7 3 Television 100 0 8 3 Radio 70 1 9 8 Webradio 90 0 I read a few things about hierarchical data, but I somehow get stuck on the multiple inner joins on the parentIDs. Maybe someone could help me out here. moon

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  • Error in retrieving data from Excel File

    - by Sreejesh Kumar
    I have an excel file. I wanted to pull the data from excel file to SQL Server table. And the data is successfully transferred.In the excel file, I removed a text from one column named "Risk" from one row.The text was lengthy one.now the package execution fails at the source ie from the excel file. The errors are shown as "[Audit [1]] Error: There was an error with output column "Risk" (100) on output "Excel Source Output" (9). The column status returned was: "DBSTATUS_UNAVAILABLE"." and "[Audit [1]] Error: SSIS Error Code DTS_E_INDUCEDTRANSFORMFAILUREONERROR. The "output column "Risk" (100)" failed because error code 0xC0209071 occurred, and the error row disposition on "output column "Risk" (100)" specifies failure on error. An error occurred on the specified object of the specified component. There may be error messages posted before this with more information about the failure." the error occurs only when I remove this particular text from this row.

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  • Core Data multi-threading

    - by JK
    My app starts by presenting a tableview whose datasource is a Core Data SQLite store. When the app starts, a secondary thread with its own store controller and context is created to obtain updates from the web for data in the store. However, any resulting changes to the store are not notified to the fetchedresults controller (I presume because it has its own coordinator) and consequently the table is not updated with store changes. What would be the most efficient way to refresh the context on the main thread? I am considering tracking the objectIDs of any objects changed on the secondary thread, sending those to the main thread when the secondary thread completes and invoking "[context refreshObject:....] Any help would be greatly appreciated.

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  • Core Data Relationship List

    - by Dylan Copeland
    I'm not sure whether or not this is the appropriate way of doing this, but I was wondering what's the best way to approach a relationship to a value in a list with Core Data? For example, say you have a 'person' entity. Each person can have a different 'hair color'. I'm trying to basically define the hair colors in my data model and allow the 'person' entity to have a relationship to their given 'hair color. Is this possible? Good idea or bad? Thanks in advance.

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