Which is best way of creating a database for each or one table in a database in MySQL?

[Thirupathi K]

We are working on IoT device, each device will stores about 20 mb of data each month and we have 20K and more IoT devices in the filed. we need storage for 7 years. So which is best way of creating database for each device or one database with one table or one database with multiple tables ?

Try to understand that all 20,000+ IoT devices have the same data and IoT with unique ID.

Each IoT device will store 70 columns of data and insert it every 1 minute. So, it will store 1,440 rows a day, 42,300 rows per month, 518,400 rows per year, and 3,628,800 rows per 7 years. This calculation is for only one device.

Storage =appr. 1.8 GB per 7 years per IoT device. For all devices = 35 TB of data.

My questions are:

How much data can be stored in a single database?
Which is better: creating a single database or multiple databases?
Are there any issues that will occur using a single database?
is it any fetching speed issue?