MongoDB provides explain() to inspect how a query executes.

It can reveal:

• Whether MongoDB uses an index.
• Whether the query performs a collection scan.
• How many documents were examined.
• How many documents were returned.
• Query execution statistics.

For example, a query filtering users by email can be inspected using execution statistics.

const result = await User.find({
  email: 'john@example.com'
}).explain('executionStats');

console.log(result.executionStats);