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

    "Data Base Name"	"Data Base Size in MB"
    "identityiq"	"7170.04983044"
    "information_schema"	"0.00781250"
    "mysql"	"0.63037777"

    # mysqldump -u root -p identityiq > test.sql
    Enter password:
    # du -sh test.sql
    3.3G    test.sql

SELECT CONCAT(table_schema,'.',table_name) TABLES, CONCAT(ROUND(table_rows/1000000,2),'M') ROWS, CONCAT(ROUND(data_length/(1024*1024*1024),2),'G') data_size, CONCAT(ROUND(index_length/(1024*1024*1024),2),'G') index_size, CONCAT(ROUND((data_length+index_length)/(1024*1024*1024),2),'G') total_size, ROUND(index_length/data_length,2) index_data_ratio
FROM information_schema.TABLES
ORDER BY total_size DESC
LIMIT 20;