LINQ Query Expressions (C# Programming Guide) Language-Integrated Query (LINQ) is the name for a set of technologies based on the integration of query capabilities directly into the C# language (also in Visual Basic and potentially any other .NET language). With LINQ, a query is now a first-class language construct, just like classes, methods, events and so on. For a developer who writes queries, the most visible "language-integrated" part of LINQ is the query expression.
Query expressions are written in a declarative query syntax introduced in C# 3.0. By using query syntax, you can perform even complex filtering, ordering, and grouping operations on data sources with a minimum of code. You use the same basic query expression patterns to query and transform data in SQL databases, ADO.NET Datasets, XML documents and streams, and .NET collections.
The following example shows the complete query operation. For more information about the basics of LINQ in C#, see Getting Started with LINQ in C#. Tasks Concepts Other Resources. Introduction to LINQ Queries (C#) A query is an expression that retrieves data from a data source. Queries are usually expressed in a specialized query language. Different languages have been developed over time for the various types of data sources, for example SQL for relational databases and XQuery for XML. Therefore, developers have had to learn a new query language for each type of data source or data format that they must support. LINQ simplifies this situation by offering a consistent model for working with data across various kinds of data sources and formats. In a LINQ query, you are always working with objects. All LINQ query operations consist of three distinct actions: Obtain the data source. The following example shows how the three parts of a query operation are expressed in source code.
The following illustration shows the complete query operation. In the previous example, because the data source is an array, it implicitly supports the generic IEnumerable<T> interface. Tasks Reference Concepts. ASP.NET Custom Controls: Part 1. In this - the first of many parts - we will look at what a custom control is and how it differs from user controls, as well as classes that our custom controls can derive from.
In the article we will also implement a simple custom control. User Controls The composition of a user control is very simple and requires a smaller skill set than that required by custom control developers. User controls preserve the use of ASP.NET mark-up coupled with the code behind model (although inline code is an option). One of the great things about user controls is that they allow a quick conversion from something like an existing ASP.NET page to a user control - and as a result they have many similarities. Some of the similarities include the use of existing server controls that ASP.NET offers, as well as the event model that you are familiar with as ASP.NET developers.
User controls provide a quick and easy way to introduce modularity into an ASP.NET web application. User Control example 2. 3. 02. 03. 06. Common Table Expression(CTE) in Sql server 2005. SQL Server CTE Basics. The CTE was introduced into standard SQL in order to simplify various classes of SQL Queries for which a derived table just wasn't suitable. For some reason, it can be difficult to grasp the techniques of using it. Well, that's before Rob Sheldon explained it all so clearly for us. Introduced in SQL Server 2005, the common table expression (CTE) is a temporary named result set that you can reference within a SELECT, INSERT, UPDATE, or DELETE statement.
You can also use a CTE in a CREATE VIEW statement, as part of the view’s SELECT query. SQL Server supports two types of CTEs—recursive and nonrecursive. Working with Common Table Expressions You define CTEs by adding a WITH clause directly before your SELECT, INSERT, UPDATE, DELETE, or MERGE statement. [WITH <common_table_expression> [,...]] <common_table_expression>::= cte_name [(column_name [,...])] AS (cte_query) ...which can be represented like this... Creating a Nonrecursive Common Table Expression cteTotalSales (SalesPersonID, NetSales)
Web Services - SOAP, WSDL, Disco and UDDI. Web Services – SOAP, WSDL, Disco and UDDI In this tutorial you will learn about Web Services – Understanding Web Services, Simple Object Access Protocol (SOAP), The Web Service Discovery Tool (DISCO), Universal Description, Discovery and Integration (UDDI), Web Service Discovery Language (WSDL).
Understanding Web Services Interconnectedness engendered by the World Wide Web has created a pressure to create applications that are interoperable and distributable over the network. The direction of effort is towards creating applications that connect to each other regardless of the language or platform in which the application was created. Web services are externally exposed systems that allow applications to talk to each other and share information over a network. The concept behind web services is not new. Prior to the emergence of Visual Studio.NET in the market a number of technologies attempted to cater to the needs of the Web based world.
Disco and UDDI. Code for Windows Forms Controls. Code for Windows Forms Controls Visual Studio .NET 2003 This topic is designed to help you find code that demonstrates how to perform common programming tasks with Windows Forms controls. The following categories are represented in the list below: You can also find sample code for Windows Forms applications in these locations: Putting Controls on Forms Example of...
Arranging Controls Labeling Controls Button Control CheckBox Control ColorDialog Component ComboBox, ListBox, CheckedListBox Controls DataGrid Control DateTimePicker Control DomainUpDown Control ErrorProvider Control FolderBrowser Control FontDialog Component ImageList Component Label Control LinkLabel Control ListView Control MainMenu, MenuItem, ContextMenu Components MonthCalendar Control NotifyIcon Component NumericUpDown Control OpenFileDialog Component PageSetupDialog Component Panel Control PictureBox Control PrintDialog, PrintDocument, PrintPreviewDialog Components ProgressBar Control RichTextBox Control SaveFileDialog Component Splitter Control Show:
XML Schema Tutorial. Home > Learn XML > XML Whitepapers > XML Schema White Papers > XML Schema Tutorial Introduction In the XML world, structure is everything. An XML document without a specific, well-defined structure is just an ad-hoc set of tags. Until relatively recently, though, one language to describe those tags, Document Type Definitions or DTDs, lacked the ability to specify information about tags as holders of data.
In addition, it was written using a dialect of SGML that runs completely counter to the current XML specification. It was for these reasons that the XML Schema Definition Language, or XSD specification, was ultimately developed. This XML Schema tutorial covers a technical overview of building XML schemas, which can make it much easier to both validate an XML document (check to make sure that its data is at least internally consistent) and to better map XML documents to binary data structures used in traditional programming. Building Schema Instances There are two ways to design schemas. Improve your communication skills - Rediff.com Get Ahead. Home > Get Ahead > Careers > Advisory > Nasha Fitter Improve your communication skills November 28, 2005 How do I improve my communication skills?
Every person with his/ her eye on the BPO pie, is asking this question today. BPO training expert, Nasha Fitter, guides you on how to brush up your spoken and written communication skills. As an under-graduate student, this will be my first ever encounter for an interview, looking for a job in a call centre and I am clueless as to what I would come across for the interview. -- Jasper Every call centre has individual interviewing techniques. The first round is usually extempore, where you are asked to talk about a topic. The second round tends to be a personal interview. In many call centres, the third round will be conducted by someone from Operations. Many call centres also have psychometric testing. I am a BCom graduate and am looking for a job in a call centre. How can I improve my level of confidence and the level of fluency in English?