Master database
Abstract
Overview of Sitecore Master databases supported infrastructure, references, scaling, and privacy and security.
The Master database contains all published and unpublished content for all publishing targets.
You can host the Master database on:
SQL Server
SQL Azure
Refer to the Sitecore compatibility table for compatible versions.
The Master database has its place in the Sitecore reference structure. It can be referenced by other roles, and it can also reference other roles.

Referenced by
The Master database is referenced by the following roles:
References
The Master database does not reference other roles.
Assuming default behavior, the Master database does not handle personal data.