SQL SUM

The SQL SUM function returns the sum value of all rows in a select query.

SELECT SUM(table_column)
FROM table_name;

ID	Title	Price	Description
1	Learn SQL	20	Learn SQL language
2	Learn MySQL	22	Learn MySQL language
3	HTML book	17	Learn HTML
4	Learn PHP	20	Introduction to PHP
5	Learn PHP	20	PHP course

SELECT SUM(price) 
FROM coder_books;

SELECT price, SUM(price) sum_price
FROM coder_books
GROUP BY price
HAVING count(*) > 1;

Price	sum_price
20	60