Sync databases, WordPress workflow

Hi

I’m trying to improve my development workflow and I’ve read many articles but can’t seem to find any that answers my question. If I have 3 environments for my website; local dev, staging and production. How do I make sure the content of the databases are in sync with one another. For example; I update my plugins, wp core(which includes upgrading the database) in the local environment and test before pushing to the staging before the production site. But in the meantime an editor has created some new posts and users have completed some contact forms etc on the production site. I also work on some custom development on the local site and want push these changes to prod without overwriting any content updates on the production site.

How do I make sure the updates and new content from both sites are merged together? Do I need to make the production site under construction while I update to stop any content changes to the production site? Surely there a neater way to do this to limit downtime and duplicate entries in the database?

What do you recommend?

Thanks