To display a breakdown of the sizes of all the tables in your database:
SELECT
table_schema AS `Database`,
table_name AS `Table`,
ROUND((data_length + index_length) / 1024 / 1024, 2) `Size in MB`
FROM
information_schema.TABLES
ORDER BY
(data_length + index_length) DESC;
If you’d just like to see the total, simply use a SUM() function like this:
SELECT
SUM(ROUND((data_length + index_length) / 1024 / 1024, 2)) `Size in MB`
FROM
information_schema.TABLES

