SQL primary key is a column in a table which uniquely identifies each row/record in a database table. Primary keys must have unique values. A primary key column cannot have NULL values. A table can have only one primary key, which may consist of single or multiple columns.
SQL Server provides the concept of temporary table which helps the developer to many ways. Temporary tables can be created at run-time and can do all kinds of operations that a normal table can do. But, based on the table types, the scope is limited. These temporary tables are created inside tempdb database.
SQL UPDATE statement is used to modify the existing records in a table. Which record is to be update it is decided by a condition. To specify condition, we use WHERE clause. If you used WHERE clause with UPDATE query to update selected records otherwise , all the records would be affected.
HtmlHelper class create the output html elements using the model properties in razor view. The property to be used to create the HTML is passed to the method as a lambda expression. It binds the model property to html elements to display value of model properties into html elements and also assigns the value of the html elements to the model properties while submitting web form. So always use HtmlHelper class in razor view instead of writing html tags directly.
The IN operator allows you to give multiple values in a WHERE clause. SQL IN operator is used in SQL statements to help reduce the multiple SQL "OR" conditions. It is used in SELECT, INSERT, UPDATE or DELETE statement.
An interface contains only the declaration of the methods, properties, and events, but not the implementation. It is the responsibility of the deriving class to implementation for all the members of the interface. By using Interface make easy to maintain a program. In C#, an interface can be defined using the interface keyword. For example, the following is a simple interface:
A StringBuilder object is not a string StringBuilder object used for manipulating characters. StringBuilder object is mutable it means once we create string builder object we can perform any operation like insert, append, remove, and replace without creating new instance for every time.