Search Results

Search found 64711 results on 2589 pages for 'core data'.

Page 79/2589 | < Previous Page | 75 76 77 78 79 80 81 82 83 84 85 86  | Next Page >

  • net c# lock statement in data access layer

    - by Pedro Rivera
    I saw a code where they have the data access layer like this: public class CustomerDA{ private static readonly object _sync = new object(); private static readonly CustomerDA _mutex = new CustomerDA(); private CustomerDA(){ } public CustomerDA GetInstance(){ lock(_sync){ return _mutex; } } public DataSet GetCustomers(){ //database SELECT //return a DataSet } public int UpdateCustomer(some parameters){ //update some user } } public class CustomerBO{ public DataSet GetCustomers(){ //some bussiness logic return CustomerDA.GetInstance().GetCustomers(); } } I was using it, but start thinking... "and what if had to build a facebook like application where there are hundreds of thousands of concurrent users? would I be blocking each user from doing his things until the previous user ends his database stuff? and for the Update method, is it useful to LOCK THREADS in the app when database engines already manage concurrency at database server level?" Then I started to think about moving the lock to the GetCustomers and UpdateCustomer methods, but think again: "is it useful at all?"

    Read the article

  • Data not displayed first time in android after copying the file from assets to data folder

    - by Thinkcomplete
    Description I have used the code tip from http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/ to copy a pre-filled data file to the target and handled this in a asynch task Problem : On starting the application it gives error and shuts down first time, starting again without any change it works perfectly fine. So first time after the file is copied, the error comes but after that no issues. Please help Code attached:.. private class CopyDatabase extends AsyncTask<String, Void, Boolean> { private final ProgressDialog dialog = new ProgressDialog(BabyNames.this); protected void onPreExecute() { this.dialog.setMessage("Loading..."); this.dialog.show(); } @Override protected Boolean doInBackground(String... params) { // TODO Auto-generated method stub try { namesDBSQLHelper.createDatabase(); return null; } catch(IOException ioe){ ioe.printStackTrace(); } return null; } protected void onPostExecute(final Boolean success){ if (this.dialog.isShowing()){ this.dialog.dismiss(); } } }

    Read the article

  • Updating/Inserting multiple rows using jQuery and OData (WCF Data Services)

    - by Pieter
    I have three tables, Template, Fields and TemplateFields. TemplateFields holds the selected fields for each template. I need to update TemplateFields when the user is finished selecting the fields. The only way I can see to do this is by deleting all the TemplateFields for that Template and then add them one by one in separate requests. This is really bad because there is not transaction to fall back onto and there will also be MANY requests. Is there a way of adding multiple 'objects' at once using WCF Data Services? I can then use an Interceptor to update the database.

    Read the article

  • Declaring STL Data Structures such as Vector in the .h

    - by sc_ray
    I am trying to declare a private Data Structure such as the Vector in my C++ header file which I want to eventually use within the method implementation of my .cpp. An example would be my header "SomeClass.h" where I have: class SomeClass { private: Vector<T> myVector; public: void AddTtoMyVector(T add); } And in my .cpp which is "SomeClass.cpp", I have the following: #include "SomeClass.h" SomeClass::AddTtoMyVector(T add) { myVector.Push_back(add); } Would the syntax here work? Or is there a different way of declaring and populating such structures?

    Read the article

  • Determining Connections between data in a single table

    - by user1689749
    Hi I'm a BA / programmer type doing data analysis on a legacy system. I've been teaching myself SQL to help, but I've appeared to hit upon a problem bigger than my abilities. I have two tables (generalized for simplicity): Table Objects Object_PK Table Components Component_PK Object_FK Component_Type There are 100+ distinct values in Component_Type_Code. Given that any object can have N number of Components, how can I see which Component_Type(s) appear with other Component_Type(s)? For example, the following query tells me what component_types appear with the component_type 'Component_type_1': select component_type_code, count(*) from components where object_fk in ( select object_fk from components where component_type_code = 'component_type_1' ) group by component_type_code I'd like to get a query to show me all connections My apologies for the formatting. Any help is appreciated. I've looked at cube and rollup, but didn't know how to apply to this situtation.

    Read the article

  • Revisions: algorithm and data structure

    - by SODA
    Hi, I need ideas for structuring and processing data with revisions. For example, I have a database of objects (e.g. cars). Each object has a number of properties, which can be arbitrary, so there's no a set schema to describe these objects. These objects are probably saved as key-value pairs. Now I need to change property of an object. I don't want to completely rewrite it - I want to be able to go back and see history of changes to these properties, that's why I want to add new property and keep the old one (so I guess a timestamp would do the job of telling which property is the latest). At the same time I want to be able to get info about any object in a snap, with only latest versions of each of the properties. Any ideas what would be the best approach? At least please point me in the right direction. Thanks!

    Read the article

  • Adding a new column to Table which contains live data

    - by Ardman
    I have a large table consisting of over 60 millions records and I would like to add 2 new columns for data migration purposes. There are indexes on the table and some of them are large. So, by me adding the 2 new columns to the table, will I run the risk of slowing down the database whilst it attempts to add them and maybe time-out? Or will it just work? I know that if I try and rearrange the columns SQL Server will ask me to drop and re-create the table, so I definately don't want this. Is this something everyone is challenged with?

    Read the article

  • data path (travel) of tcp data from "write" syscall downto I/O registers programming

    - by osgx
    Hello Is there a good overview of tcp data path in Linux (2.6, not 2.4 if the path actually differ)? Where is a packet on different stages of tcp/ip stack handling? How packet is packed to tcp segment, then ip packet. How it is transmitted to network card? (with series of I/O regs write and DMA?) Is it transmitted to network card in the "write" syscall handler (with some deep callstack) or is it transmitted at some other moment?

    Read the article

  • Determining Excel spreadsheet format before Data Flow Task

    - by Josh Larsen
    I'm working on an SSIS package which uses a for each loop to iterate through excel files in a directory and a data flow task to import them. The issue I'm having is that the project manager I'm working with doesn't think the users will always follow the structure. So if a file is in the folder and the package tries to import it but the spreadsheet is missing columns or has extra columns it generates and error of course. Even though I have the task set to not fail the package; the package does indeed fail and then the other files aren't imported. So, I'm wondering what is the easiest way to either determine the spreadsheet is incorrectly formatted, or stop the error from failing the package execution? After taking said step I would just use a file copy task to move the file to a "Failure" folder. Then continue on processing the spreadsheets.

    Read the article

  • How to deal with the limited Linq Support of OData (Open Data Protocol)

    - by user341127
    I have a software, which uses a lot of Linq to SQL. Recently, I want to immigrate to OData (or WCF Data Service) architecture. But I met too many problems in Linq for the Linq support of OData is so limited. I have to modify most of my Linq statements and test them thoroughly again. I am wondering whether there is a system way to solve such a problem instead of my manual work. For example, by an external package. BTW, now I have no confidence to use OData as a kind of architecture. You are appreciated to share your ideas. Thank you in advance, Ying

    Read the article

  • How to get data from another page (different servers)

    - by rjovic
    I want to make a IE8 web slice who will show remaining amount of students "food credit". In our country we have web page where we can see ammount www.cap.srce.hr/ProvjeraSaldo.aspx. When I fill textbox with my card number i recieve remaining amount. Now, i want to speed that process with ie8 web slice. So is it possible to get data from another webserver page and than display it in my web slice on my web server. I tried to use XMLHTTP request but it can be only used on same domains. Url for getting amount is : http://www.cap.srce.hr/saldo.aspx?brk={number_of_card}

    Read the article

  • Best means to store data locally when offline

    - by mickartz
    I am in the midst of writing a small program (more to experiment with vs 2010 than anything else) Despite being an experiment it has some practical use for our local athletics club. My thought was to access the DB (currently online) to download the current members and store locally on a laptop (this is a MS sql table, used to power the club's website). take the laptop to the event (yes there ARE places that don't have internet coverage), add members to that days race (also a row from a sql table (though no changes would be made to this), record results (new records in 3rd table) Once home, showered and within internet access again, upload/edit the tables as per the race results/member changes etc. So I was thinking i'd do something like write xml files locally with the data, including a field to indicate changes etc? If anyone can point me in a direction i would appreciate it...hell if anyone could tell me if this has a name, I'd appreciate it.

    Read the article

  • Get notified about the change in raw data in hard disk sector - File change notification

    - by Nuv
    I'm trying to make a software that backups my entire hard drive. I've managed to write a code for reading the raw data from hard disk sectors. However, i want to have incremental backups. For that i need to know the changed made to OS settings, file changes, everything. My question is - Using FileSystemWatcher and Inotify, will i be able to know every change made to every sector in the hard drive ? (OS settings etc) I'm coding it in C++ for linux and windows. (Saw this question on Stackoverflow which gave me some idea)

    Read the article

  • How to find thousands of company names?

    - by schefdev
    How can I find or generate thousands of company names for testing and demo purposes? (Address, phone number, and related information would be nice too.) I've got a system I'm building which includes business contact information. Pretty common no doubt. My test/demo database currently has randomly generated individual's names loaded (thanks to a handy IRS spreadsheet I found). This has worked great for internal testing and review purposes, but it looks really odd when shown to prospective customers. I've tried various online public information sources (e.g. EDGAR, and county based property records searches), but these all require me to manually stitch together the results in blocks of 50 names or so at a time. I could do this, but was really hoping for a search service or data store out there that had this type of information readily searchable and retrievable in very large batches.

    Read the article

  • Is there a work-around that allows missing data to equal NULL for LOAD DATA INFILE in MySQL?

    - by richardh
    I have a lot of large csv files with NULL values stored as ,, (i.e., no entry). After a lot of searching I found that this is a known "bug", although it may be a feature for some users. Is there a way that I can fix this on the fly without pre-processing? These data are all numeric, so a zero value is very different from NULL. Or if I have to do pre-processing, is there one that is most promising for dealing with tens of csv files of 100mb to 1gb? Thanks!

    Read the article

  • Appropriate data structure for a buffer of the packets

    - by psihodelia
    How to implement a buffer of the packets where each packet is of the form: typedef struct{ int32 IP; //4-byte IP-address int16 ID; //unique sequence id }t_Packet; What should be the most appropriate data structure which: (1) allows to collect at least 8000 such packets (fast Insert and Delete operations) (2) allows very fast filtering using IP address, so that only packets with given IP will be selected (3) allows very fast find operation using ID as a key (4) allows very fast (2), then (3) within filtered results ? RAM size does matter, e.g. no huge lookup table is possible to use.

    Read the article

  • How to use C# nested structures to access tree of data

    - by zotty
    I'm importing some XML to C#, and want to be able to access data from the XML in the form of what I think is a nested structure. (I may be wrong!) What I have in my XML is in the following form: <hardwareSettings initial="true> <cameraSettings width="1024" height="768" depth="8" /> <tiltSettings theta="35" rho="90"> </hardwareSettings> I can import each setting alright, so I have them all in individual ints, but I would like to be able to access it in the form int x=hardwaresettings.camerasettings.width; int rho=hardwaresettings.tiltsettings.rho; I've tried various arrangements of structs within structs, but I don't seem able to cast a new object (hardwaresettings) that contains the appropriate children (camerasettings.width & tiltsettings.rho). Sorry if I'm not using the right lingo... I'm reading myself in circles here!

    Read the article

  • Grouping data into ranges in R

    - by Maddy
    supposing i have a data frame in R that has names of students in one column and their marks in another column. these marks range from 20 to 100. > mydata id name marks gender 1 a1 56 female 2 a2 37 male i want to divide the student into groups, based on the criteria of obtained marks, so that difference between marks in each group should be more than 10. i tried to use the function table, which gives the number of students in each range from say 20-30, 30-40, but i want it to pick those students that have marks in a given range and put all their information together in a group. any help is appreciated.

    Read the article

  • Data persistance with BufferedReader and PrintWriter?

    - by Nazgulled
    I have this simple application with a couple of classes which are all related. There's one, the main one, for which there is only one instance of. I need to save save and load that using a text stream. My instructor requirement is BufferedReader to load the stream and PrintWriter to save it. But is this even possible? To persist a data object/class with a text stream? I know how to do it with and object, using serialization. But I don't see how am I supposed to do it using text streams. Suggestions?

    Read the article

  • Connect Android application to remote data

    - by tadywankenobi
    Sheesh talk about limited information! I'm trying to get my Android application to connect to an online database to access information. There's quite a bit of info including geotags and these are going to be mapped on my app. The developer site has the very informative piece of information: You can use the network (when it's available) to store and retrieve data on your own web-based services. To do network operations, use classes in the following packages: java.net.* android.net.* Like I said in my previous question, I'm still very much an android newbie, and trying to remember my java oop from college is slow. Does anyone have an example of how this might work, or how I could implement it? I wouldn't mind even connecting to a local xml file, if I could find a good example of how to do that!? Am I just looking in all the wrong places?! Help. Please! T

    Read the article

  • Facebook Like button data for a domain?

    - by mungojerie
    We make a widget for media sites and have included the Facebook Like button, so anyone who installs our widget gets the Like button on every page without having to do additional integration work. We'd like to show the site owner some basic data / analytics about Like activity... which URLs are liked, and how many times. I can't figure out if this is even available via the Graph API or FQL. If it is, I can't tell if I need an app_id and secret token for each domain or not. Any suggestions?

    Read the article

  • Flex/Air: Sending data with a certificate

    - by BS_C3
    Hello Community, I need to send data from an Air application, using a certificate. This certificate is to be provided by the user through a USB Key. I've got a lot of questions regarding this. Is it possible to do what I'm looking for? If yes, is it possible to do that only with the Flex/Air sdk or should I use Java or some other language to load the certificate? Would anyone have a link where I can learn some more about this? I've been looking through the web, but haven't really found anything useful... Thanks for any help you can provide. Regards. BS_C3

    Read the article

  • Sending data between forms without using .Show()

    - by slodice
    Lets say I have 2 forms. In Form1 I have a timer, which counts (count++) and in Form2 I have a text box (textBox1) which shows how much the timer has counted. Now I want to know how would I show the integer 'count' in 'textBox1' without any user interference (clicking buttons) or in other words, how would I make the data in the text box auto refresh (without using Form2 form = new Form2(); form.Show();). I want 2 separate windows, in one a running timer and in the other a textbox displaying how much the timer has counted and constantly updating (with the help of the timer, I presume).

    Read the article

  • The best practice to setup hierarchy data

    - by eski
    I'm trying to figure out the best practice to setup hierarchy data that i take from a database into some contoller that would show the hierachy. Basicly this would look like a normal tree but when you press the items that are under "chapters" you get a link to another page. I have these tables and this is the way they are connected Period Courses Subjects Chapters I select Period from a DropDownBox and then i want all the courses in that period to line up. Under each course would be the subject and under them are the chapers, typical hierarchy. The tables are linked together with refrences to each other in linear way. I have tried to use treeview to show this, but dont understand how to do it. I though i could use <ul><il> tags and do it at runtime. Reapeter or datalist, possible ? Is it better to do this with databinding in XAML or in code ?

    Read the article

  • DataContext Doesn't Exist in Dynamic Data Project?

    - by davemackey
    This is really annoying...and I know it is something extremely simple... 1. I create a new Dynamic Data project. 2. I add a LINQ-to-SQL class and drag and drop some tables onto the class. 3. I open the global.asax.vb and uncomment the line: DefaultModel.RegisterContext(GetType(YourDataContext), New ContextConfiguration() With {.ScaffoldAllTables = True}) I remove YourDataContext and replace it with the DataContext from my LINQ-to-SQL class: DefaultModel.RegisterContext(GetType(NorthwindDataContext), New ContextConfiguration() With {.ScaffoldAllTables = True}) I then try to debug/build/etc. and receive the following error: Type 'NorthwindDataContext' is not defined Why is it not defined? It seems like its not recognizing I created the DBML file.

    Read the article

< Previous Page | 75 76 77 78 79 80 81 82 83 84 85 86  | Next Page >