MongoDB Custom Validation Tutorial

Create a Collection with Custom Validation

Create a MongoDB collection named 'products' with validation rules that require 'productName' as a string and 'price' as a positive number.

Expected output: A 'products' collection that rejects documents missing 'productName' or with 'price' less than or equal to zero.

Hint: Use $jsonSchema with required fields and minimum value constraints.

Update Validation Rules

Modify the 'products' collection to add a new rule that the 'category' field, if present, must be one of 'electronics', 'clothing', or 'food'.

Expected output: The 'products' collection enforces the new category constraint on inserts and updates.

Hint: Use the collMod command with an updated validator including an enum for 'category'.

JSON Schema validation uses a declarative schema to enforce document structure and data types, while validation expressions use MongoDB query operators to define custom logical conditions for validation.

MongoDB performs validation during insert and update operations to ensure documents meet the defined validation rules before being saved.

You can modify validation rules on an existing collection using the collMod command with updated validator, validationLevel, and validationAction options.