Difference between Session and Cookies
Session["userName"] = "Ganesh Ram";
if(Session["UserName"] != null)
lblUserName.Text = Session["UserName"].ToString(); //add a username Cookie
Response.Cookies["UserName"].Value = "Ganesh Ram";
Response.Cookies["UserName"].Expires = DateTime.Now.AddDays(10);
//request a username cookie
if(Request.Cookies["UserName"] != null)
lblUserName.Text = Server.HtmlEncode(Request.Cookies["UserName"].Value); 
Difference between Clustered index and Non-Clustered index
Whereas in case of non-clustered index the leaf level is actually a pointer to the data in rows so we can have as many non-clustered indexes as we can on the db
Example
USE Sample
GO
CREATE TABLE Employee
(ID bigint PRIMARY KEY CLUSTERED,
Name nvarchar(150),
Address nvarchar(250),
Salary varchar(25) )
GO
CREATE NONCLUSTERED INDEX EmpName ON Employee(Name)
GO
Define Stored procedure ?
It is a collection of transact sql statements that can take or return user supplied parameters.
Maximum size of stored procedure is 128 MB.
Difference between Having and Group By clause ?
Having Clause : To filter the rows from the grouped results
Group By : is used for grouping the operation.
Group by : Ccause is used to group the output of the WHERE clause..
Define View ?
It is nothing but a virtual table that represent the data in one or more tables in a alternative way.
What is index ?
Index is a pointer in sql server to retrieve the data faster from database.
It’s a physical structure containing pointers to data.
Its created in existing tables to locate rows more quickly and efficiently.
Types of Index:
a) Clustered Index : It contains only one index ie: Creating a primary key for the table.
Physical sorting of data in the storage media.
b) Non-Clustered Index : A table can contains 249 non-clustered index, It can be created outside of the database tables , that contain a sorted list of references to the table itself.
Define Delegates ?
Delegate is a class that can hold reference to a method or a function .
Delegate class has a signature and it only reference those method whose signature is compliant with the class.
Delegates are type safe , secure , object oriented.
Difference b/w int.Parse and Convert.ToInt32()?
Int.Parse – It can’t handle NULL value.
Convert.ToInt32 – It handles null value and converts value to default value ‘0’.
What is Finalize and Dispose ?
Finalize: - Automatically done by garbage collector to clean the resource memory.
Dispose: - Force the user to dispose objects.
Boxing and Unboxing ?
Boxing:
Implicit conversion of any value type to the type object.
Value types are stored on stack.
Reference or object type are stored on heap.
Unboxing:
Explicit conversion from object type to value type.
Reflection ?
You can see the metadata information through reflection mechanism.
Ability to inspect and manipulate programs elements at runtime.
It’s the process of runtime type discovery.
Reflection Services:
Load an assembly at runtime.
Enumerate members of a type.
Instantiate a new object.
Execute the members of an object.
Find out the information about a type .
Find out the information about a assembly
Inspect custome attributes applied to a type.
Create and compile new assembly.
What is Session ?
Session is used to store user details particularly userid and user information so once you set the information in session you can get the data anywhere in the project .
Syntax:
Session[“username”] = “Venkat”;
How to write stored procedure – give syntax ?
Create Procedue <procedureName>
(
Your parameter
)
As
Begin
< your Sql Statement>
End
Difference between timestamp and uniqueidentifier ?
TimeStamp:
Size – 8 bytes.
Note based on system date or time
To track the operation in tables on the database level.
Uniqueidentifier
16 – bytes.
Value is based on the computer MAC Addresss and system datetime.
It remains unique in any system in the world.
How to convert from string to GUID ?
String mystring = “xxxx-xxxx-xxxx-xxxx”;
Guid = new Guid(mystring);
Newid() = Globally unique identifier
NewSequentialId() – Globally sequential identifier
Where the session is stored ?
<sessionState mode =”InProc” cookieless=”False” timeout=”20”/>
By default Cookieless is set to false – so the session Id is stored in Cookies so as long as user navigating the page you can get the session from cookies.
If you set the cookieless =”True” the session id is stored on the browser url before the file name
Ex: http://yourserver/folder/(sessionid)/default.aspx
Default timeout for session is 20 Mins.
Default timeout for Form authentication 30 Mins.
How to display the Name on Email to address
EX:
MailMessage msg = new MailMessage();
Msg.from = new mailAddress(“youraddress@gmail.com”, “Test”);
Form authentication Configuration
<authentication mode=”forms”>
<forms name =”.ASPXAUTH” login url=”login.aspx” protection=”All” timeout=”30” path=”/”/>
</authentication>
How to keep the session alive?
<sessionState timeout=”20” mode=”InProc” />
By default slidingexpiration is enabled = “true” so when the momen postback occurs or user utilizing the controls, session timeout counter is refreshed so the session remains active.
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