MongoDB vs PostgreSQL for a scalable blog CMS — which is better?

[august-rainn]

Body

I'm building a blog CMS backend and trying to decide between MongoDB and PostgreSQL.

The system includes:

• Users & authentication
• Posts with categories and tags
• Comments (possibly nested)
• Likes / reactions

I understand MongoDB is flexible, but PostgreSQL seems better for relationships.

For long-term scalability and performance:

• Which database would you recommend?
• Are there any trade-offs I should be aware of?
• Has anyone switched from one to the other in a similar project?

Would really appreciate real-world experiences 🙏

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