Note: You do not need to change the 'Database Name' entry

SELECT table_schema "Database Name",

    sum( data_length + index_length ) / 1024 / 1024 "Database Size in MB",

    sum( data_free )/ 1024 / 1024 "Free Space in MB"

FROM information_schema.TABLES

GROUP BY table_schema ; 

The following commands should be run inside mysql
Note: replace “Data Base Name” with the db name.

SELECT table_schema "Data Base Name",

    sum( data_length + index_length ) / 1024 / 1024 "Data Base Size in MB",

    sum( data_free )/ 1024 / 1024 "Free Space in MB"

FROM information_schema.TABLES

WHERE table_schema = "$DATABASE_NAME";