AVG() Function in SQL Server

AVG() :

This function in SQL Server is used to return the average value of the specified expression.

Features :

• This function is used to find the average value of the specified expression.
• This function comes under Numeric Functions.
• This function accepts only one parameter, namely expression.
• This function ignores NULL values.

Syntax :

AVG(expression)

Parameter :

This method accepts one parameter.

• expression – A specified numeric value may be either a stated field or a stated formula.

Returns :

It returns the average value of the specified expression.

Example-1 :

Using AVG() function and getting the output.

CREATE TABLE product
(  
user_id int IDENTITY(100, 2) NOT NULL,    
product_1 VARCHAR(10),
product_2 VARCHAR(10),
price int  
);
INSERT product(product_1, price)  
VALUES ('rice', 400);

INSERT product(product_2, price)  
VALUES ('grains', 600);

SELECT AVG(price) FROM product;

Output :

500

Here, the average of the first product’s price and second product’s price is returned.

Example-2 :

Using AVG() function and getting the average of float values.

CREATE TABLE floats
(  
user_id int IDENTITY(100, 2) NOT NULL,
float_val float
);
INSERT floats(float_val)  
VALUES (3.5);

INSERT floats(float_val)  
VALUES (2.5);

SELECT AVG(float_val) FROM floats;

Output :

3

Example-3 :

Using AVG() function and getting the output where MRP is greater than the average MRP of the products.

CREATE TABLE package
(  
user_id int IDENTITY(100, 4) NOT NULL,  
item VARCHAR(10),
mrp int  
);
INSERT package(item, mrp)  
VALUES ('book1', 250);

INSERT package(item, mrp)  
VALUES ('book2', 350);

INSERT package(item, mrp)  
VALUES ('book3', 400);

SELECT * FROM package
WHERE mrp > (SELECT AVG(mrp) FROM package);

Output :

  | user_id  | item     | mrp
--------------------------------
1 | 104      | book2    | 350
--------------------------------
2 | 108      | book3    | 400

Example-4 :

Using AVG() function and getting the average of the (MRP-sales price).

CREATE TABLE package
(  
user_id int IDENTITY(100, 4) NOT NULL,  
item VARCHAR(10),
mrp int,
sp int
);
INSERT package(item, mrp, sp)  
VALUES ('book1', 250, 240);

INSERT package(item, mrp, sp)  
VALUES ('book2', 350, 320);

INSERT package(item, mrp, sp)  
VALUES ('book3', 400, 350);

SELECT AVG(mrp-sp) FROM package;

Output :

30

Application :

This function is used to find the average of the expression specified.