BSON

BSON

Filename extension	.bson
Internet media type	none
Type of format	Data interchange
Extended from	JSON
Standard(s)	no RFC yet
Website	bsonspec.org

BSON ( /ˈbiːsɒn/) is a computer data interchange format used mainly as a data storage and network transfer format in the MongoDB database. It is a binary form for representing simple data structures and associative arrays (called objects or documents in MongoDB). The name "BSON" is based on the term JSON and stands for "Binary JSON".

Data types and syntax

BSON documents (objects) consist of an ordered list of elements. Each element consists of a field name, a type, and a value. Field names are strings. Types include:

• string
• integer (32- or 64-bit)
• double (64-bit IEEE 754 floating point number)
• date (integer number of milliseconds since the Unix epoch)
• byte array (binary data)
• boolean (true and false)
• null
• BSON object
• BSON array
• regular expression
• JavaScript code

BSON types are nominally a superset of JSON types (JSON does not have a date or a byte array type, for example), with one exception of not having a universal "number" type.

Efficiency

Compared to JSON, BSON is designed to be efficient both in storage space and scan-speed. Large elements in a BSON document are prefixed with a length field to facilitate scanning. In some cases, BSON will use more space than JSON due to the length prefixes and explicit array indices.

See also

• JSON
• Protocol Buffers
• Action Message Format
• Apache Thrift
• MessagePack
• Document-oriented database
• Abstract Syntax Notation One (ASN.1)

External links

• BSON documentation on the MongoDB website