How to Get True Size of MySQL Database?

Question

From S. Prakash, found at the MySQL forum:

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; 

Or in a single line for easier copy-pasting:

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; 

You can get the size of your Mysql database by running the following command in Mysql client

SELECT  sum(round(((data_length + index_length) / 1024 / 1024 / 1024), 2))  as "Size in GB"
FROM information_schema.TABLES
WHERE table_schema = "<database_name>"

If you use phpMyAdmin, it can tell you this information.

Just go to "Databases" (menu on top) and click "Enable Statistics".

You will see something like this:

This will probably lose some accuracy as the sizes go up, but it should be accurate enough for your purposes.

if you want to find it in MB do this

SELECT table_schema                                        "DB Name", 
   Round(Sum(data_length + index_length) / 1024 / 1024, 1) "DB Size in MB" 
FROM   information_schema.tables 
GROUP  BY table_schema; 

Basically there are two ways: query DB (data length + index length) or check files size. Index length is related to data stored in indexes.

Everything is described here:

http://www.mkyong.com/mysql/how-to-calculate-the-mysql-database-size/