External sort
Updated: 10/01/2023 by Computer Hope
In computer science, external sorting is a technique that efficiently organizes large datasets that cannot fit in RAM (random-access memory) by utilizing sorting algorithms. When dealing with data that exceeds a computer's memory capacity, external sorting algorithms are useful because they minimize the resource-intensive I/O (input/output) operations.
Essentially, an entire dataset is divided into smaller parts that fit in the device's memory. Then, these chunks are put through an internal algorithm and merged to produce a final, sorted output. During this process, "excess" data is temporarily kept on an external storage medium, usually a disk drive.