Introduction to MongoDB cursor.pretty() Method

MongoDB is a popular document-oriented database that supports the use of cursors to retrieve query results. When handling query results, the cursor.pretty() method can be used to format the results for easier readability and understanding.

Syntax

The syntax for the cursor.pretty() method is as follows:

db.collection.find().pretty()

Use Cases

When the documents returned by a query are very complex or nested, the results may be difficult to read and understand. In such cases, the cursor.pretty() method can be used to format the results for better display, which is useful for developers when debugging and optimizing queries.

Examples

Assuming there is a collection named “students” that contains many student documents, the following example code demonstrates the use of the cursor.pretty() method to format query results:

var cursor = db.students.find({ age: { $gte: 18 } })
printjson(cursor.pretty())

In the example above, we first use the db.students.find() method to query for student documents that are 18 years old or older and store the query results in a cursor named cursor. Then we use the printjson() method and the cursor.pretty() method to format the query results for easy reading.

Here is a more practical example. Suppose we need to query the “products” collection for all products that are priced above 50 yuan and sort the results in descending order by price. We can use the cursor.pretty() method to format the results for better display.

var cursor = db.products.find({ price: { $gt: 50 } }).sort({ price: -1 })
printjson(cursor.pretty())

In the example above, we first use the db.products.find() method to query for all products priced above 50 yuan and sort the results in descending order by price. Then we use the printjson() method and the cursor.pretty() method to format the query results for easy reading.

Conclusion

The cursor.pretty() method is a very useful method for formatting query results for easier readability and understanding. By using this method, we can better debug and optimize queries and display query results more effectively.