MongoDB – Overview of collection and document

MongoDB is a NoSQL, document-oriented database designed to store, retrieve, and manage large volumes of semi-structured or unstructured data. Unlike traditional relational databases that store data in tables and rows, MongoDB uses a more flexible model, where data is stored in documents (in BSON format), which is a binary form of JSON. These documents are organized into collections, which are roughly equivalent to tables in relational databases.

MongoDB – Collection and Document (In Short)

1. Document:
   • A document in MongoDB is a basic unit of data and is similar to a row in relational databases.It is stored in a BSON (Binary JSON) format, which is a binary representation of JSON (JavaScript Object Notation).A document can contain key-value pairs, where values can be strings, numbers, arrays, nested documents, or other data types.Documents are schema-less, meaning different documents in the same collection can have different structures.
   Example:

{ 
"name": "John Doe", "age": 30,
 "address": 
   { "street": "123 Main St", 
   "city": "Springfield" }, 
"skills": ["JavaScript", "MongoDB"] 
}

1. Collection:
   • A collection in MongoDB is a group of documents. It is similar to a table in relational databases.Collections are schema-less, meaning that they can hold documents with varying structures.Collections are created automatically when documents are inserted, and there is no need to define the structure beforehand.
   Example: A collection named users might contain multiple documents, such as the one shown above for a user named “John Doe.”
2. In MongoDB:
   • users is a collection that could store many user documents.

Summary:

• Document: A single record in MongoDB, similar to a row in a relational database.
• Collection: A grouping of documents, similar to a table in a relational database.