Increase in mysql database size(ibdata1)

[Vijay Kumar]

Hi,

We are using Mysql database which has some tables which gets updated every hour.
The table has columns like datetime, int and bigint.
As per the data storage requirement , for every hour the database should increase by 0.25GB, but the size is increasing by 1 GB every hour.

We have calculated size based on the data type column, and number of records in the table.
Example for int I am conisdering as 4 byte, 8 bytes for bigint, 8 bytes for datetime column.
we are usinng InnoDb storage engine

Should I consider some other factors while calculating the db size.