Introduction to Aggregate Functions

SQL aggregate functions in MySQL are powerful tools for performing calculations on sets of values and returning a single result. These functions enable you to summarize and analyze your data, and they are commonly used in reports and data analysis.


SUM Function

The 

SUM
function calculates the sum of a numeric column's values. For example:

            SELECT SUM(sales)
            FROM orders;

This query calculates the total sales from the "orders" table.


AVG Function

The 

AVG
function calculates the average of numeric column values. For instance:

            SELECT AVG(salary)
            FROM employees;

This query computes the average salary of employees.


COUNT Function

The 

COUNT
function counts the number of rows in a result set. You can use it to count all rows or specific rows based on conditions:

            SELECT COUNT(*)
            FROM customers;

This query counts all rows in the "customers" table.


MIN and MAX Functions

The 

MIN
and 
MAX
functions return the minimum and maximum values from a column, respectively:

            SELECT MIN(price), MAX(price)
            FROM products;

This query finds the minimum and maximum product prices.


Conclusion

SQL aggregate functions in MySQL are essential for summarizing and analyzing data. You've learned about 

SUM
, 
AVG
, 
COUNT
, 
MIN
, and 
MAX
. These functions are invaluable for reporting, data analysis, and making data-driven decisions in your applications.