What is a linked list and how it works? What are advantages and disadvantages of linked lists?

A linked list is a linear collection of data elements called nodes, pointing to the next node by means of pointer. It is a data structure consisting of a group of nodes which together represent a sequence. Under the simplest form, each node is composed of data and a reference (in other words, a link) to the next node in the sequence; but there are more complex variants, which introduce additional links. This structure allows for efficient insertion or removal of elements from any position in the sequence.

Types of joins in SQL

SQL join is an instruction to a database to combine data from more than one table. There are different kinds of joins, which have different rules for the results they create. In most SQL implementations you may find such joins as inner join, left join, right join, full join and also language implementation specific ones.

What is POCO and what is DTO in the .NET world?

Plain Old CLR Object or POCO is a play on the term POJO, from the Java programming world (which was coined by Martin Fowler in 2000) and is used by developers targeting the Common Language Runtime of the .NET Framework. POCO is a concept that has been the source of many misconceptions because of the similarity with the concept of DTO (Data Transfer Object).

What is dynamic type in C#? How it is different from object?

C# 4.0 introduced a new type, dynamic. The type is a static type, but an object of type dynamic bypasses static type checking. In most cases, it functions like type object. At compile time, an element that is typed as dynamic is assumed to support any operation. Therefore, you do not have to be concerned about where the object gets its value from. However, if the code is not valid, errors are caught at run time.

What is ADO.NET?

ADO.NET is a feature of Microsoft .NET Framework that you can use to access and manipulate data. It is a part of the base class library that is included with the .NET Framework. It is commonly used by programmers to access and modify data stored in relational database systems, though it can also access data in non-relational sources.

What is encapsulation in OOP?

Encapsulation is one of the four fundamental OOP concepts. It is the inclusion within a program object of all the resources needed for the object to properly function on its own - basically, the methods and the data. The object has its public interface and other objects adhere to these interface to use the object without having to be concerned with how the object internally implements it. The idea is "don't tell me how you do it; just do it".