27 January 2014

Why Select is DML statement in SQL?

Why Select is DML statement in SQL?

DML - Data Manipulation Language

The purely read-only SELECT query statement is classed with the 'SQL-data' statements 

The SELECT ... INTO form is considered to be DML because it manipulates (i.e. modifies) data.

SELECT Column1, Column2
INTO DestinationTable

FROM SourceTable

Copy Coumn1,Column2 From SourceTable to DestinationTable.


So Select is dml statement

Other DML Statement are
Insert, Update and Delete


19 January 2014

Session Add, Remove, Clear, RemoveAll and Abandon in ASP.NET

Session Add, Remove,  Clear, RemoveAll  and Abandon in ASP.NET

1. Session Add

To add in the Session
For ex
Session.Add("UserID",1);
   or
Session["UserID"]=1;

UserID is Session ID
1 is Session value

2. Session Remove

Session.Remove(“UserID”);
It removes the specific session’s specific key value i.e) It removes the SessionID UserID


3. Session Clear

Session.Clear()
It clears all session value i.e) It clears all the key value pairs stored in the session state collection.

4. Session RemoveAll

Session.RemoveAll();
This Method calls above clear method in its implementation,
public sealed class HttpSessionState : ICollection, IEnumerable
{
   .....
   public void RemoveAll()
   {
       this.Clear();
   }
   .....
}

5. Session Abandon

Session.Abandon() destroy everything in the session. While logout you have to clear everything in session.




Handling Session in Common Class in ASP.NET WebForms or ASP.NET MVC

Handling Session in Common Class in ASP.NET WebForms or  ASP.NET MVC

SessionVariables.cs
using System;
using System.Web;
namespace WebApplication1
{
    public class SessionVariables
    {

        ///
        ///  Store EmpID in Session
        ///
        public static Int64 EmpID
        {
            get
            {
                return (Int64)HttpContext.Current.Session["EmpID"];
            }

            set
            {
                HttpContext.Current.Session["EmpID"] = value;
            }
        }
       
       
        ///
        /// Store EmpName in Session
        ///
        public static string EmpName
        {
            get
            {
                return (string)HttpContext.Current.Session["EmpName"];
            }

            set
            {
                HttpContext.Current.Session["EmpName"] = value;
            }
        }
     
    }

}

You can get or set the session variables in Webforms or MVC

using System;
using System.Web.UI;

namespace WebApplication1
{
    public partial class HandlingSession : Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            SessionVariables.EmpID = 1;

            SessionVariables.EmpName = "ArunPrakash";
        }
    }
}

Advantages:
1. Reduces duplicate Session variables declaration
2. Type conversion is in common functions.

ActionResult in MVC 4

ActionResult in MVC 4

The ActionResult class is the base class for action results.

An action method responds to user input by performing work and returning an action result. An action result represents a command that the framework will perform on behalf of the action method.

The following types derive from ActionResult:

ContentResult - Represents a user-defined content type that is the result of an action method.

EmptyResult - Represents a result that does nothing, such as a controller action method that returns nothing.

FileResult - Represents a base class that is used to send binary file content to the response.

HttpUnauthorizedResult - Represents the result of an unauthorized HTTP request.

JavaScriptResult - Sends JavaScript content to the response.

JsonResult - Represents a class that is used to send JSON-formatted content to the response.

RedirectResult - Controls the processing of application actions by redirecting to a specified URI.

RedirectToRouteResult - Represents a result that performs a redirection by using the specified route values dictionary.

ViewResultBase - The ViewResultBase class is the abstract base class for both the ViewResult and PartialViewResult classes. The class contains methods for finding the view to be rendered and for executing the result. This class also contains properties that identify the view to be rendered, the name of the view, view data, temporary data, and a collection for view engines for the application.

Reference
http://msdn.microsoft.com/en-us/library/system.web.mvc.actionresult(v=vs.118).aspx

9 January 2014

Set the selected item in an ASP.NET dropdown via the display text

Set the selected item in an ASP.NET dropdown via the display text

Method 1:
ddlItemdetails.Items.FindByText("Shirts").Selected = true;

Method 2:

ddlItemdetails.SelectedValue = ddItems.Items.FindByText("Shirts").Value;


Consistency level in Azure cosmos db

 Consistency level in Azure cosmos db Azure Cosmos DB offers five well-defined consistency levels to provide developers with the flexibility...