Is MongoDB good or bad?

1. Lack of ACID Transactions (Improved Over Time)

• MongoDB was historically criticized for weak ACID compliance, but it has significantly improved with multi-document transactions starting in version 4.0.

2. Overhead for Complex Relationships

• MongoDB is not ideal for applications requiring complex relationships or heavy joins, as it does not inherently support foreign key constraints.

3. Storage Overhead

• The JSON-like data format (BSON) can result in higher storage requirements compared to relational databases.

4. Learning Curve for SQL Users

• Users familiar with SQL may find MongoDB’s query language and concepts less intuitive initially.

When MongoDB is a Good Choice

• Applications requiring flexibility and rapid schema changes.
• Projects involving large-scale, unstructured, or semi-structured data.
• Systems that prioritize high performance and scalability over strict relational constraints.

When MongoDB Might Not Be the Best Fit

• Applications requiring strict ACID compliance across complex transactions.
• Systems heavily dependent on structured data with predefined schemas and complex relationships (e.g., financial systems).

Conclusion

MongoDB is "good" for use cases that benefit from flexibility, scalability, and performance, but it may not be the best choice for relational, transaction-heavy systems. Carefully consider your project requirements before choosing MongoDB or any database technology.