Database architecture affects how businesses separate customers, permissions, backups and operational information. Isolation can make those boundaries clearer.
Separate tenants clearly
When each business has its own database, the storage boundary is explicit rather than being only a logical partition inside one shared database.
Simplify business-level backup and portability
Independent storage can make business-specific backup, restore and migration workflows easier to reason about.
Combine isolation with access control
Database separation is one layer of security. Authentication, authorisation, encryption, backups and monitoring remain important as well.
No architecture removes every security risk, but clear data boundaries can be a strong part of a privacy-first business platform.