BSON is a binary storage format for JSON data. The BSON specification is located at https://bsonspec.org/. BSON maintains the overall structure of JSON text data, but encodes data type, variable length, and nesting information. BSON is designed to be lightweight so there is little additional overhead as compared to text-based JSON in terms of storage. BSON is easily traversable and efficient in terms of the time needed to convert to and from BSON.
- Object
- Array
- String
- Number
- Null
- Boolean
- Binary data
- Floating point
- Date
- Timestamp
- When exchanging data with MongoDB
- When retrieval of portions of the document is more important than insertion time
- When compactness of storage is not as important as retrieval speed
BSON encodes strings in the UTF-8 character set. The character set for BSON data when imported or exported as text is UNICODE.
Numeric types are serialized in little-endian format. If data is imported to or exported from the database in the BSON format (using constructor/instance methods or cast expressions), it is expected to be in this format.