Interview Questions: Indexes in SQL, What is Index? It’s purpose?
What is Index? It's purpose?
Indexes in databases are similar to indexes in books. In a database,
an index allows the database program to find data in a table without
scanning
the entire table. An index in a database is a list of values
in a table with the storage locations of rows in the table that
contain each value. Indexes can be created on either a single column
or a combination of columns in a table and are implemented in the form
of B-trees. An index contains an entry with one or more columns (the
search key) from each row in a table. A B-tree is sorted on the search
key, and can be searched efficiently on any leading subset of the
search key. For example, an index on columns A, B, C can be searched
efficiently on A, on A, B, and A, B, C.
ASP.NET Features and Advantages
ASP.NET is a compiled, .NET-based environment; you can code the applications in any .NET compatible language, including Visual Basic .NET, C#, and JScript .NET. Additionally, the entire .NET Framework is available to any ASP.NET application.
ASP.NET has been designed with scalability in mind, with features specifically tailored to improve performance in clustered and multiprocessor environments. With built in Windows authentication and per-application configuration, you can be assured that your applications are secure. 
You can use Web Forms or XML Web services when creating an ASP.NET application, or combine both depending on your need. Both of them allows you to use authentication schemes, cache frequently used data, or customize application's configuration.
ASP.Net allows programmers to develop web applications that interface with a database. The advantage of ASP.Net is that it is object-oriented and has many programming tools that allow for faster development and more functionality.
There are 2 aspects of ASP.Net make it fast, compiled code and caching.
Prior to DOT Net Framework, the code was interpreted into machine language when your website visitor views your page. Now, with ASP.Net the code is compiled into machine language before your visitor ever comes to your site.
Caching is the storage of information that will be reused in a memory location for faster access in the future. ASP.Net allows programmers to set up pages or areas of pages that are commonly reused to be cached for a set period of time to improve the performance of web applications. I have used caching in many of my applications with few records, static and frequently used data.
ASP.Net automatically recovers from memory leaks and errors to make sure that your website is always available to your visitors. Programmers can actually write their code in any of the supported .Net languages like VB.Net, C#, and JScript.Net. In the Learning series, we will be using C# since it’s the widely used language across many companies.
An ASP.NET Framework application is deployed to a server simply by copying the necessary files to the server. No server restart is required, even to deploy or replace running compiled code.
Security is one of the major advantage, you can use built in Windows authentication and also you can set the security configuration by application.
C# interview questions
- What’s the advantage of using System.Text.StringBuilder over System.String? StringBuilder is more efficient in the cases, where a lot of manipulation is done to the text. Strings are immutable, so each time it’s being operated on, a new instance is created.
- Can you store multiple data types in System.Array? No.
- What’s the difference between the System.Array.CopyTo() and System.Array.Clone()? The first one performs a deep copy of the array, the second one is shallow.
- How can you overload a method? Different parameter data types, different number of parameters, different order of parameters.
- If a base class has a bunch of overloaded constructors, and an inherited class has another bunch of overloaded constructors, can you enforce a call from an inherited constructor to an arbitrary base constructor? Yes, just place a colon, and then keyword base (parameter list to invoke the appropriate constructor) in the overloaded constructor definition inside the inherited class.
- What’s the difference between System.String and System.StringBuilder classes? System.String is immutable; System.StringBuilder was designed with the purpose of having a mutable string where a variety of operations can be performed.
- What’s a delegate? A delegate object encapsulates a reference to a method. In C++ they were referred to as function pointers.
- What’s a multicast delegate? It’s a delegate that points to and eventually fires off several methods.
More: http://tipsinterview.com/doc/Csharp_Interview_Questions.doc
