Function in SQL

Introduction to Function in SQL

Introduction:

In this article, you will learn what function is and how many types of functions are used in SQL.

SQL function is used to show the functionality of the database records, which we create or delete, according to our condition. It is a collection of SQL statements, which allows the input parameters, depending on which, it simply takes some types of inputs and displays a result accordingly, nothing more or less than that. The function is executed each time, whenever it was called.

Type of Function

The SQL function is divided into two major parts like stored procedure:

System Defined Functions

These type of functions, SQL Server already contains, which will be difficult to implement without the System Defined Functions. This function is easily mixed with the complicated and immediately required operations.

User Defined Functions

This function returns a value, based on the user-defined condition. User Defined Functions are used to create an easy statement. It generates at the time of execution, which is based on these parts:

Scalar-valued function: A user-defined function can return a scalar value, we use this statement in all the database.

Inline function: When a user-defined function holds the Select statement, that is updatable or not, the tabular result returned by the function is also updatable. These functions are called inline functions. We can use these functions in the 'Form clause of another query.

Table-valued function: When a user-defined function holds the Select statement, that is updatable or not, this Table-valued function returned is not updatable. Table-valued function shows a table and we can use these functions in the 'Form clause of another query.

Advantage of Functions

The SQL Server function have some advantages like:

• We can use these functions with where, having (clause).

• They can be used in a 'Select statement'.

• These are based on the function oriented.

• These functions are easy to use.

Summary:
Thus, we learned that function shows the functionality of the data and it depends on SQL statement.