Data Model and Data Types

In MongoDB, data is stored in BSON format, which supports various data types. Understanding these data types is essential as they play a crucial role in schema design and query performance. The following is a brief summary of the different data types supported in MongoDB.

ObjectId

ObjectId is a 12-byte identifier used as a unique identifier for documents in a collection. It is the default value generated for the _id field, ensuring uniqueness within the collection.

String

String is used to store text data. It must be a valid UTF-8 encoded string.

{
   "name": "John Doe",
}

Boolean

Boolean is used to store true or false values.

{
   "isActive": true,
}

Integer

Integer is used to store an integer value. MongoDB supports two integer types: 32-bit (int) and 64-bit (long).

{
   "age": 28,
}

Double

Double is used to store floating-point numbers.

{
   "price": 12.99,
}

Date

Date is used to store the date and time in Unix time format (milliseconds timestamp since January 1, 1970, 00:00:00 UTC).

{
   "createdAt": ISODate("2019-02-18T19:29:22.381Z"),
}

Array

Array is used to store a list of values in a single field. The values can be of different data types.

{
   "tags": ["mongodb", "database", "noSQL"],
}

Object

Object is used to store embedded documents, meaning a document can contain another document.

{
   "address": { "street": "123 Main St", "city": "San Francisco", "state": "CA" },
}

Null

Null is used to store a null value, representing the absence of a value or the field.

{
   "middleName": null,
}

Binary Data

Binary Data is used to store binary data or byte arrays.

{
   "data": BinData(0, "c3VyZS4="),
}

Code

Code is used to store JavaScript code.

{
   "script": Code("function() { return 'Hello, World!'; }"),
}

Regular Expression

Regular Expression is used to store regular expressions.

{
   "pattern": /^mongodb/i,
}

Understanding and using the appropriate data types while designing your MongoDB schema can significantly improve the performance, storage, and retrieval of your data. Don't forget to consider the specific use cases of your application when choosing data types.