SQL Aggregate Functions are used to perform mathematical operations on sets of values in a database table. They are used to summarize data and provide statistical information about the data. In this blog, we will discuss five commonly used SQL Aggregate Functions: SUM, AVG, MAX, MIN, and COUNT.
SUM Function
The SUM function is used to calculate the sum of all the values in a specified column of a database table. The syntax of the SUM function is as follows:
SELECT SUM(column_name)
FROM table_name;
For example, consider a table "sales" that has a "revenue" column. We can use the SUM function to calculate the total revenue of the company.
SELECT SUM(revenue)
FROM sales;
AVG Function
The AVG function is used to calculate the average value of a specified column of a database table. The syntax of the AVG function is as follows:
SELECT AVG(column_name)
FROM table_name;
For example, consider a table "employees" that has a "salary" column. We can use the AVG function to calculate the average salary of the employees.
SELECT AVG(salary)
FROM employees;
MAX Function
The MAX function is used to find the maximum value in a specified column of a database table. The syntax of the MAX function is as follows:
SELECT MAX(column_name)
FROM table_name;
For example, consider a table "products" that have a "price" column. We can use the MAX function to find the most expensive product.
SELECT MAX(price)
FROM products;
MIN Function
The MIN function is used to find the minimum value in a specified column of a database table. The syntax of the MIN function is as follows:
SELECT MIN(column_name)
FROM table_name;
For example, consider a table "products" that has a "price" column. We can use the MIN function to find the least expensive product.
SELECT MIN(price)
FROM products;
COUNT Function
The COUNT function is used to count the number of rows in a database table. The syntax of the COUNT function is as follows:
SELECT COUNT(*)
FROM table_name;
For example, consider a table "customers". We can use the COUNT function to count the total number of customers.
SELECT COUNT(*)
FROM customers;
Conclusion
SQL Aggregate Functions are a powerful tool for summarizing data in a database table. In this blog, we covered five commonly used Aggregate Functions: SUM, AVG, MAX, MIN, and COUNT. Understanding these functions and their syntax is essential for working with large datasets and generating statistical information about the data.