SELECT table_schema, sum( data_length + index_length )/1024/1024 "Data Base Size in MB" FROM information_schema.TABLES GROUP BY table_schema;
Get total size of all MySQL databases on a server

Comments
1
SELECT table_schema, sum( data_length + index_length )/1024/1024 "Data Base Size in MB" FROM information_schema.TABLES GROUP BY table_schema;