Development, Staging and Production Enterprise WordPress

Hi everyone,
I’m looking for best practice to maintain and develop an enterprise wordpress installation.
I need to point out how to handle site development, staging and production in correct way.
I aim to near zero downtime during site updates and migrations.
Many themes and plugins write their configurations on database. What is the best practice to handle database, media and theme updates in wordpress (i.e. from staging to production)?

Thanks for your support.
Simone