What is the difference between RDBMS relationships and MongoDB s data model

Question

Can i know What is the difference between RDBMS relationships and MongoDB’s data model?

Answer 1

Feature	RDBMS (SQL Databases)	MongoDB (NoSQL Document Database)
Data Structure	Tables with rows & columns	JSON-like BSON documents
Schema	Fixed schema (strict structure)	Schema-less (flexible structure)
Relationships	Uses foreign keys & JOINs	Uses embedding or referencing
One-to-One	Separate tables with foreign keys	Embedded document or referencing ObjectID
One-to-Many	Foreign key in the child table	Embedded array of sub-documents or referencing
Many-to-Many	Junction table with foreign keys	Referencing with arrays of ObjectIDs
Normalization	High normalization to reduce redundancy	Denormalization for performance optimization
JOIN Support	Supports JOIN operations	No JOINs, uses embedding or $lookup