What is a cursor in MongoDB?

A cursor in MongoDB is an object that allows you to iterate over the results of a query. When a query is executed, instead of returning all matching documents at once, MongoDB returns a cursor, which acts as a pointer to the result set. This means that you can retrieve the documents one by one or in batches, which is particularly useful for working with large datasets.

The cursor provides methods that allow you to operate on the resulting documents, such as navigating to the next document, iterating through the results, or limiting the number of results returned. This mechanism helps with memory efficiency and allows for more control over how the queried data is processed.

By understanding the function of a cursor, you can better manage the way you retrieve and manipulate data in MongoDB. Cursors can also be configured with options to sort or filter results, further enhancing your ability to work with data effectively.