root@zwc 11:11:29>SELECT  
    -> ROUND(  
    -> SUM(data_length + index_length) / 1024 / 1024  
    -> ) TOTAL_MB,  
    -> ROUND(SUM(data_length) / 1024 / 1024) DATA_MB,  
    -> ROUND(  
    -> SUM(index_length) / 1024 / 1024  
    -> ) INDEX_MB  
    -> FROM  
    -> information_schema. TABLES;  
+----------+---------+----------+  
| TOTAL_MB | DATA_MB | INDEX_MB |  
+----------+---------+----------+  
|      944 |     466 |      478 |  
+----------+---------+----------+  
1 row in set (0.04 sec)  

root@zwc 11:16:13>SELECT  
    -> TABLE_SCHEMA,  
    -> ENGINE,  
    -> ROUND(  
    -> SUM(data_length + index_length) / 1024 / 1024  
    -> ) TOTAL_MB,  
    -> ROUND(SUM(data_length) / 1024 / 1024) DATA_MB,  
    -> ROUND(  
    -> SUM(index_length) / 1024 / 1024  
    -> ) INDEX_MB,  
    -> count(*) "TABLES"  
    -> FROM  
    -> information_schema. TABLES  
    -> GROUP BY  
    -> TABLE_SCHEMA,  
    -> ENGINE  
    -> ORDER BY 3 DESC;  
+--------------------+--------------------+----------+---------+----------+--------+  
| TABLE_SCHEMA       | ENGINE             | TOTAL_MB | DATA_MB | INDEX_MB | TABLES |  
+--------------------+--------------------+----------+---------+----------+--------+  
| zwc                | MyISAM             |      485 |     191 |      294 |      1 |  
| zwc                | InnoDB             |      456 |     273 |      183 |      1 |  
| common_schema      | InnoDB             |        2 |       2 |        0 |     11 |  
| mysql              | MyISAM             |        1 |       1 |        0 |     22 |  
| information_schema | MyISAM             |        0 |       0 |        0 |      9 |  
| mysql              | CSV                |        0 |       0 |        0 |      2 |  
| information_schema | MEMORY             |        0 |       0 |        0 |     28 |  
| common_schema      | MyISAM             |        0 |       0 |        0 |      7 |  
| performance_schema | PERFORMANCE_SCHEMA |        0 |       0 |        0 |     17 |  
| common_schema      | NULL               |     NULL |    NULL |     NULL |     62 |  
+--------------------+--------------------+----------+---------+----------+--------+  
10 rows in set (0.03 sec)  


SELECT
TABLE_SCHEMA,
ENGINE,
ROUND(
SUM(data_length + index_length) / 1024 / 1024
) TOTAL_MB,
ROUND(SUM(data_length) / 1024 / 1024) DATA_MB,
ROUND(
SUM(index_length) / 1024 / 1024
) INDEX_MB,
count(*) "TABLES"
FROM
information_schema. TABLES
GROUP BY
TABLE_SCHEMA,
ENGINE
ORDER BY 3 DESC;


SELECT
ROUND(
SUM(data_length + index_length) / 1024 / 1024
) TOTAL_MB,
ROUND(SUM(data_length) / 1024 / 1024) DATA_MB,
ROUND(
SUM(index_length) / 1024 / 1024
) INDEX_MB
FROM
information_schema. TABLES;