Differents between ExecuteReader, ExecuteNonQuery & ExecuteScalar

-
ExecuteReader : Use for accessing data. It provides a forward-only, read-only, connected recordset.

ExecuteNonQuery : Use for data manipulation, such as Insert, Update, Delete.

ExecuteScalar : Use for retriving 1 row 1 col. value.,
i.e. Single value.
eg: for retriving aggregate function.
It is faster than other ways of retriving a single value from DB.

Comments

Post a Comment

Popular posts from this blog

Auto Refresh .aspx page - ASP.NET

-
Method 1: Response.AddHeader To Refresh Web page After every 5 Seconds You can add following code, Response.AddHeader("Refresh", "5"); Cricket Sites, Stock Exchange sites use similar logic :) Method 2: In body Tag, window.setTimeout The 1000 = 1 Second... < body onload ="window.setTimeout('window.location.reload()',1000);" > Method 3: In Meta Tag Theres also a meta tag that you can define on the head, but not sure wheter it refreshes even if the content has not finished loading or if it starts counting when the head section loaded. Code would be something like that: < meta content ="600" http-equiv ="refresh" > Method 4: Timer Control : Microsoft ASP.NET 2.0 AJAX Extensions server control In following example, the timer interval is set to 10 seconds <%@ Page Language="C#" AutoEventWireup="true" %> <! DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN...
Read more

MVC Request Execution Stages - Life Cycle

-
Image
Back to Home Execution Stages: For web: HTTP request for Application Incoming request routed to Controller (Perform Routing) The controller processes request and create presentation Model The controller also selects appropriate result (view) Model is passed to View View transforms Model into an appropriate output format (HTML) The response is rendered (HTTP response) Image Courtesy: SlideShare.net  Back to Home
Read more

SOLID Principles with C#

-
SOLID Principles are coding standards that all developers should have a clear concept for developing software in a proper way to avoid a bad design. S - Single Responsibility Principle (SRP): A class should have one, and only one, a reason to change In Single Responsibility Principle Each class and module should focus on a single task at a time Everything in the class should be related to that single purpose There can be many members in the class as long as they related to the single responsibility With SRP, classes become smaller and cleaner Code is less fragile  Here  UserAccount  class created which have below operations like, Login, Register, LogError and Send Mail. According to SRP, ideally, LogError and SendEmail are should not be part of  UserAccount  operations.      public class UserAccount     {         public bool Login( string username, ...
Read more

Overview of MVC

-
Overview of the ASP.NET MVC - Introduction to ASP.NET MVC -  ASP.NET MVC Version History -  Life Cycle of MVC request -  Role of Model, View, and Controller -  Works Behaviour of ASP.NET MVC -  Benefits MVC Architecture - Razor View Engine - Essential Language Features & Helpers - Basic Helpers - Strongly-Typed Helpers - Creating Custom Helpers - Declarative Helpers The MVC Pattern - The MVC Design Pattern - Working with Controllers - Model Templates - MVC State Management - Working with URLs and Routing (URL Routing) - Bundling and Minification Working with Controllers - Controller Actions - Controller and ActionResult Types - Passing Data from View to Controller - Action Filters & Custom Action Filter - Action Selectors HttpGet and HttpPost Razor Views - Razor View Engines and Syntax - Working with Layout Pages - Views & Partial Vi...
Read more

Parsing the comma separated values into a temporary table

-
(Works in both SQL Server 7.0 and 2000) Declare @OrderList varchar (500) set @OrderList = 'Order1,Order2,,Order3,,,Order4,Order5,' ; drop TABLE #TempList CREATE TABLE #TempList ( OrderID varchar (20) ) DECLARE @OrderID varchar (10), @Pos int SET @OrderList = LTRIM(RTRIM(@OrderList))+ ',' SET @Pos = CHARINDEX( ',' , @OrderList, 1) IF REPLACE(@OrderList, ',' , '' ) <> '' BEGIN WHILE @Pos > 0 BEGIN SET @OrderID = LTRIM(RTRIM( LEFT (@OrderList, @Pos - 1))) IF @OrderID <> '' BEGIN INSERT INTO #TempList (OrderID) VALUES (@OrderID) END SET @OrderList = RIGHT (@OrderList, LEN(@OrderList) - @Pos) SET @Pos = CHARINDEX( ',' , @OrderList, 1) END END SELECT * FROM #TempList t +-+-+-+-+-+ OUTPUT +-+-+-+-+-+ OrderID -------- -- Order1 Order2 Order3 Order4 Order5
Read more

Polymorphism in C#

-
Polymorphism means having more than one form.   Overloading and overriding are used to implement polymorphism.  Polymorphism Examples Method Overloading Method Overriding There are two type of Polymorphism  1. Compile time polymorphism (Early binding or static binding)  Examples: overloaded methods, overloaded operators and overridden methods that are called directly by using derived objects. 2. Run time polymorphism (Late binding or dynamic binding)   Example: overridden methods that are called using base class object.  
Read more

Page Life Cycle in ASP.NET

-
Image
Life cycle when the page processed during a postback The events associated with the relevant page cycle phases are: Page Initialization: Page_Init View State Loading:LoadViewState Postback data processing: LoadPostData Page Loading: Page_Load PostBack Change Notification: RaisePostDataChangedEvent PostBack Event Handling: RaisePostBackEvent Page Pre Rendering Phase: Page_PreRender View State Saving: SaveViewState Page Rendering: Page_Render Page Unloading: Page_UnLoad The processing sequence in which a page is processed during a postback event is: Initializing: During this phase, the server creates an instance of the server control Loading view state: During this phase, the view state of the control posted by the client is reloaded into the new instance of the control. Loading : During this phase, the instance of the control is loaded onto the page object in which it is defined. Loading the postback data : During this phase, the server s...
Read more

LINQ - C# Programming

-
Get DataSource In C# as in most programming languages a variable must be declared before it can be used. In a LINQ query, the from clause comes first in order to introduce the data source (customers) and the range variable (cust). //QEmp is an IEnumerable var QEmp = from e in Emp select e; Filter Probably the most common query operation is to apply a filter in the form of a Boolean expression. The filter causes the query to return only those elements for which the expression is true. The result is produced by using the where clause. The filter in effect specifies which elements to exclude from the source sequence. var QEmp = from e in Emp where e.Country == "India" select e ----AND Condition---- where e.Country == "India" && e.Name == "Ashvin" ----OR Condition---- where e.Country == "India" || e.Name == "Ashvin" Ordering The orderby clause will cause the elements in the...
Read more

How to Edit More than 200 Rows in SQL Server 2008

-
How to Edit More than 200 Rows in SQL Server 2008 Management Studio Step 1: In SQL Server 2008 Management Studio, go to "Tools" -> "Options" -> "SQL Server Object Explorer" -> "Commands". Step 2: Now in "Table and View Options" section, you can change either: #Value for Edit Top Rows command, to a value greater than or less than 200. #Value for Select Top Rows command, to a value greater than or less than 1000. Step 3: By specifying a value of 0, SQL Server will return all rows. (If you sql tables are really large data volume, you should NOT set these values to 0.) Step 4: Click OK to save your changes.
Read more