Search Results

Search found 75615 results on 3025 pages for 'www data'.

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 396/3025 | < Previous Page | 392 393 394 395 396 397 398 399 400 401 402 403  | Next Page >

  • How to index a table with a Type 2 slowly changing dimension for optimal performance

    - by The Lazy DBA
    Suppose you have a table with a Type 2 slowly-changing dimension. Let's express this table as follows, with the following columns: * [Key] * [Value1] * ... * [ValueN] * [StartDate] * [ExpiryDate] In this example, let's suppose that [StartDate] is effectively the date in which the values for a given [Key] become known to the system. So our primary key would be composed of both [StartDate] and [Key]. When a new set of values arrives for a given [Key], we assign [ExpiryDate] to some pre-defined high surrogate value such as '12/31/9999'. We then set the existing "most recent" records for that [Key] to have an [ExpiryDate] that is equal to the [StartDate] of the new value. A simple update based on a join. So if we always wanted to get the most recent records for a given [Key], we know we could create a clustered index that is: * [ExpiryDate] ASC * [Key] ASC Although the keyspace may be very wide (say, a million keys), we can minimize the number of pages between reads by initially ordering them by [ExpiryDate]. And since we know the most recent record for a given key will always have an [ExpiryDate] of '12/31/9999', we can use that to our advantage. However... what if we want to get a point-in-time snapshot of all [Key]s at a given time? Theoretically, the entirety of the keyspace isn't all being updated at the same time. Therefore for a given point-in-time, the window between [StartDate] and [ExpiryDate] is variable, so ordering by either [StartDate] or [ExpiryDate] would never yield a result in which all the records you're looking for are contiguous. Granted, you can immediately throw out all records in which the [StartDate] is greater than your defined point-in-time. In essence, in a typical RDBMS, what indexing strategy affords the best way to minimize the number of reads to retrieve the values for all keys for a given point-in-time? I realize I can at least maximize IO by partitioning the table by [Key], however this certainly isn't ideal. Alternatively, is there a different type of slowly-changing-dimension that solves this problem in a more performant manner?

    Read the article

  • How should my application keep clients in sync with schema changes to HTML5 databases?

    - by Chad Johnson
    I'm wanting to incorporate HTML5 database storage into my web application to make it online-accessible. I've done lots of development in server-side environments with databases, and we all know that database schema additions and modifications are often necessary. I am wondering what should happen if my application uses an offline database schema, and that schema changes. How do I prevent the application from breaking on the client side? How do I ensure the database is always up to date on the client end? Anyone have any solutions?

    Read the article

  • How to convert an application to be a database independent app ?

    - by Eslam
    I have a java web application that has informix DB as it's back end database , now i take a decision to make my app work with SqlServer so i changed all the informix related syntax into SqlServer, and i may take a decision in the future to switch into oracle so the pain will be repeated again and again, as a result i decided to make my application a DataBase independent one that's able to work with any DB vendor smoothly, but i have no idea till now about how to do that, so your ideas is welcomed.

    Read the article

  • Loading an NSArray on iPhone from a dynamic data base url in PHP or ASP

    - by Brad
    I have a database online that I would like to be able to load into an NSArray in my app. I can use arrayWithContentsOfURL with a static file, but I really need to go to a url that generates a plist file from the database and loading it into the array. I can use ASP or PHP. I tried setting the response type to "text/xml", but that doesn't help. Any thoughts?

    Read the article

  • Fact table with multiple facts

    - by Jeff Meatball Yang
    I have a dimension (SiteItem) has two important facts: perUserClicks perBrowserClicks however, within this dimension, I have groups of dimensions based on an attribute column (let's call the groups AboveFoldItems, LeftNavItems, OnTheFlyItems, etc.) each have more facts that are specific to that group: AboveFoldItems: eyeTime, loadTime LeftNavItems: mouseOverTime OnTheFlyItems: doesn't have any extra, but may in the future Is the following fact table schema ok? DateKey SessionKey SiteItemKey perUserClicks perBrowserClicks eyeTime loadTime mouseOverTime It seems a little wasteful since only some columns pertain to some dimension keys (the irrelevant facts are left NULL). But... this seems like it would be a common problem, so there should be a common solution for this, right?

    Read the article

  • In App Purchase Unique Identifying Data

    - by dageshi
    O.K so I'm writing a iPhone travel guide, you purchase a subscription to a travel guide for 3 months, it downloads a fairly hefty database and for 3 months that database gets updated weekly with new stuff. Now what I'd like to do is make the user enter their email address as a one off action before they purchase their first guide, for China say. The purpose for doing this is 1) To allow me to contact the user by email when they add a note/tip for a particular place (the app will allow them to send notes & information to me) 2) To Uniquely identify who has purchased the subscription so that if they wipe their device and reinstall the app they can plug the email address in and pickup their subscriptions again. Or so they can use the same subscription on another device they own. My concerns are 1) Will Apple allow the email method of restoring functionality to a second or restored device? 2) As long as I tell the user what I'm using their email address for (aka I won't sell it to anyone else and use it for X purposes) will it be o.k to ask for said email address? And as a side note, can I tack the devices unique id onto my server comms to track devices or is apple going to through a hissy fit about that as well?

    Read the article

  • Should a Trim method generally in the Data Access Layer or with in the Domain Layer?

    - by jpierson
    I'm dealing with a database that contains data with inconsistencies such as white leading and trailing white space. In general I see a lot of developers practice defensive coding by trimming almost all strings that come from the database that may have been entered by a user at some point. In my oppinoin it is better to do such formating before data is persisted so that it is done only once and then the data can be in a consistent and reliable state. Unfortunatley this is not the case however which leads me to the next best solution, using a Trim method. If I trim all data as part of my data access layer then I don't have to concern myself with defensive trimming within the business objects of my domain layer. If I instead put the trimming responsibility in my business objects, such as with set accessors of my C# properties, I should get the same net results however the trim will be operating on all values assigned to my business objects properties not just the ones that come from the inconsistent database. I guess as a somewhat philisophical question that may determine the answer I could ask "Should the domain later be responsible for defensive/coercive formatting of data?" Would it make sense to have a set accessor for a PhoneNumber property on a business object accept a unformatted or formatted string and then attempt to format it as required or should this responsibility be pushed to the presentation and data access layers leaving the domain layer more strict in the type of data that it will accept? I think this may be the more fundamental question. Update: Below are a few links that I thought I should share about the topic of data cleansing. Information service patterns, Part 3: Data cleansing pattern LINQ to SQL - Format a string before saving? How to trim values using Linq to Sql?

    Read the article

  • JSF Open new window and display bean data

    - by JSFPRINTER
    I am running JSF 2.0 and the latest version of Primefaces 2.2RC1 I believe. I am trying to create a printer friendly window. When the user clicks on a p:commandLink I want a new window to open and display a xhtml file I have named printView.xhtml. Now I can get the window working fine using JavaScript window.open but when I open the new window it will not render any values it just displays everything as #{myBean.value}. Does anyone know how to properly open a window and extend the current scope of the application into that window so I can call all of my managed beans properly and display the values etc. etc.

    Read the article

  • Strategy to structure a search index in a relational database

    - by neilc
    I am interested in suggestions for building an efficient and robust structure for indexing products in a new database I am building (i'm using MySql) When a product is entered through the form there are three parts I am interested in indexing for searching purposes. The product title The product description Tags The most important is title, followed by tags, followed by the description. I was thinking of using the following structure CREATE TABLE `searchindex` ( `id` INT NOT NULL , `word` VARCHAR( 255 ) NOT NULL , `weighting` INT NOT NULL , `product_id` INT NOT NULL , PRIMARY KEY ( `id` ) ) Then each time a product is created I would split apart the title, description and tags (removing common words) and award them a weighting. Then it is trivial to select out the words and corresponding products and order them by weighting. Is there a better way to do this? I would be worried that this strategy would slow down over time and as the database filled up.

    Read the article

  • how to handle result set data

    - by ashwani66476
    Hello All I am getting lacks of records in my Result Set. My concerns are : How Result Set handle these records internally? and How a programmer can handle those records in batches So that memory problem would not occur.? waiting for your answers .. Many Thanks

    Read the article

  • How to find longest common substring using trees?

    - by user384706
    The longest common substring problem according to wiki can be solved using a suffix tree. From wiki: The longest common substrings of a set of strings can be found by building a generalised suffix tree for the strings, and then finding the deepest internal nodes which have leaf nodes from all the strings in the subtree below it I don't get this. Example: if I have: ABCDE and XABCZ then the suffix tree is (some branches from XABCZ omitted due to space): The longest common substring is ABC but it is not I can not see how the description of wiki helps here. ABC is not the deepest internal nodes with leaf nodes. Any help to understand how this works?

    Read the article

  • Retrieving data from facebook in a winform

    - by gillyb
    Hey, I understand that using the facebook API I need an api key to connect, but I still don't understand how i would go about doing this, and how can i retrieve information upon users using the API (i'm only interested in retrieving the information that is publicly available e.g: username, birthdate, and other info that a specific user left public) I downloaded the facebook development kit, and tried adding the FacebookService control, but i don't get it... All the examples/samples i found on the internet are older than the version i have and therefore work a little different.. Can someone please post an example of how i would connect, using a certain API key, and retrieve someones public info/public photos (if there are any) ?? Thanks. :)

    Read the article

  • Cleansing string / input in Coldfusion 9

    - by Jakub
    I have been working with Coldfusion 9 lately (background in PHP primarily) and I am scratching my head trying to figure out how to 'clean/sanitize' input / string that is user submitted. I want to make it HTMLSAFE, eliminate any javascript, or SQL query injection, the usual. I am hoping I've overlooked some kind of function that already comes with CF9. Can someone point me in the proper direction?

    Read the article

  • DMX Analysis Services question

    - by user282382
    Hi, I am have two mining models, both are time series. One is [Company_Inputs] and the other is [Booking_Projections]. What I want to do is use EXTEND_MODEL_CASES to join the results of [Company_Inputs] as the extended cases. So basically something like: Select Flattened PredictTimeSeries([Bookings], 1, 6, EXTEND_MODEL_CASES) FROM [Booking_Projections] Natural Prediction Join (Select Flattened PredictTimeSeries([Metric1], 1, 6) From [Company_Inputs]) AS T This code of course doesn't work, but the idea is to use the predictions made from [Company_Inputs] as cases for predicting future values of [Booking_Projections] If anyone has an idea of how I can accomplish this I would appreciate it very much.

    Read the article

  • GZipStream in an WebHttpResponse producing no data

    - by Pierre 303
    I want to compress my HTTP Responses for client that supports it. Here is the code used to send a standard response: IHttpClientContext context = (IHttpClientContext)sender; IHttpRequest request = e.Request; string responseBody = "This is some random text"; IHttpResponse response = request.CreateResponse(context); using (StreamWriter writer = new StreamWriter(response.Body)) { writer.WriteLine(responseBody); writer.Flush(); response.Send(); } The code above works fine. Now I added gzip support below. When I test it with a browser that supports gzip or a custom method, it returns an empty string. I'm sure I'm missing something simple, but I just can't find it... IHttpClientContext context = (IHttpClientContext)sender; IHttpRequest request = e.Request; string acceptEncoding = request.Headers["Accept-Encoding"]; string responseBody = "This is some random text"; IHttpResponse response = request.CreateResponse(context); if (acceptEncoding != null && acceptEncoding.Contains("gzip")) { byte[] bytes = ASCIIEncoding.ASCII.GetBytes(responseBody); response.AddHeader("Content-Encoding", "gzip"); using (GZipStream writer = new GZipStream(response.Body, CompressionMode.Compress)) { writer.Write(bytes, 0, bytes.Length); writer.Flush(); response.Send(); } } else { using (StreamWriter writer = new StreamWriter(response.Body)) { writer.WriteLine(responseBody); writer.Flush(); response.Send(); } }

    Read the article

  • Silverlight Data Binding for Collection in Stack Panel

    - by Blake Blackwell
    I'm new to Silverlight, so I don't have a complete grasp of all the controls at my disposal. What I would like to do is use databinding and a view model to maintain a collection of items. Here is some mock code for what I'd like to do: Model public class MyItem { public string DisplayText { get; set; } public bool Enabled { get; set; } } ViewModel public class MyViewModel : INotifyPropertyChanged { private ObservableCollection<MyItem> _myItems = new ObservableCollection<MyItem>(); public ObservableCollection<MyItem> MyItems { get { return _myItems; } set { _myItems = value NotifyPropertyChanged(this, "MyItems"); } } } View <Grid x:Name="LayoutRoot" Background="White"> <StackPanel ItemsSource="{Binding MyItems}"> <StackPanel Orientation="Horizontal"> <CheckBox "{Binding Enabled, Mode=TwoWay}"></CheckBox> <TextBlock Text="{Binding DisplayText, Mode=TwoWay}" /> </StackPanel> </StackPanel> </Grid> So my end goal would be that every time I add another MyItem to the MyItems collection it would create a new StackPanel with checkbox and textblock. I don't have to use a stack panel but just thought I'd use that for this sample.

    Read the article

  • how to Invoke User-Defined Functions That Return a Table Data Type

    - by nectar
    here my code- create function dbo.emptable() returns Table as return (select id, name, salary from employee) go select dbo.emptable() error: Msg 4121, Level 16, State 1, Line 1 Cannot find either column "dbo" or the user-defined function or aggregate "dbo.emptable", or the name is ambiguous. while when I run sp_helptext emptable it shows- create function dbo.emptable() returns Table as return (select id, name, salary from employee) it means function exists in database then why it is giving such error?

    Read the article

  • Subset and lagging list data structure R

    - by user1234440
    I have a list that is indexed like the following: >list.stuff [[1]] [[1]]$vector ... [[1]]$matrix .... [[1]]$vector [[2]] null [[3]] [[3]]$vector ... [[3]]$matrix .... [[3]]$vector . . . Each segment in the list is indexed according to another vector of indexes: >index.list 1, 3, 5, 10, 15 In list.stuff, only at each of the indexes 1,3,5,10,15 will there be 2 vectors and one matrix; everything else will be null like [[2]]. What I want to do is to lag like the lag.xts function so that whatever is stored in [[1]] will be pushed to [[3]] and the last one drops off. This also requires subsetting the list, if its possible. I was wondering if there exists some functions that handle list manipulation. My thinking is that for xts, a time series can be extracted based on an index you supply: xts.object[index,] #returns the rows 1,3,5,10,15 From here I can lag it with: lag.xts(xts.object[index,]) Any help would be appreciated thanks: EDIT: Here is a reproducible example: list.stuff<-list() vec<-c(1,2,3,4,5,6,7,8,9) vec2<-c(1,2,3,4,5,6,7,8,9) mat<-matrix(c(1,2,3,4,5,6,7,8),4,2) list.vec.mat<-list(vec=vec,mat=mat,vec2=vec2) ind<-c(2,4,6,8,10) for(i in ind){ list.stuff[[i]]<-list.vec.mat }

    Read the article

  • API for displaying graphs in a web app?

    - by Rosarch
    I have graphs (nodes/arcs) that I want to display to the user. I need to be able to capture the event of a user clicking on a node. Something like Google Charts API's Simple Org Chart would be great, but it looks like it only supports trees. What other service can I use? Or should I hack something ugly together using Google Charts?

    Read the article

  • How to parse json data in Python?

    - by backcross
    Please help me to parse this json in python. { "IT" : [ { "firstName" : "ajay", "lastName" : "stha", "age" : 24 }, { "firstName" : "Michiel", "lastName" : "Og", "age" : 35 } ], "sales" : [ { "firstName" : "Guru", "lastName" : "red", "age" : 27 }, { "firstName" : "Jim", "lastName" : "Galley", "age" : 34 } ] } How to parse this json in Python?Please help me

    Read the article

  • Insert data in an object to a database.

    - by paul
    I am facing the following design/implementation dilemma. I have a class Customer which is below with getters and setters. I would like to insert the value of the Customer into a "Customer" table of a database. But Customer has an address which is of type "Address". How do I go about inserting this field into the database?(I am using sqlite3). I thought of writing a separate table "Address(customerId,doorNo,city,state,country,pinCode)". But I am having second thoughts about generating the primary key(customerId) which should be same for both the "customer" and "Address" table. Sqlite3 faq states that I can do "Integer Primary Key" to use the field to generate an auto number. But if I do that in customer table, I would have to retrieve the same Id to be used in Address table. This kinda looks wrong to me :-?. There should be an elegant method to solve this. Any ideas would be much appreciated. Thanks in advance. import java.io.*; import java.sql.*; class Customer { private String id; private String name; private Address address; private Connection connection; private ResultSet resultSet; private PreparedStatement preparedStatement; public void insertToDatabase(){ } } class Address{ private String doorNumber; private String streetName; private String cityName; private String districtName; private String stateName; private String countryName; private long pinCode; }

    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 | 392 393 394 395 396 397 398 399 400 401 402 403  | Next Page >