How does DISTINCT keyword work internally in MySQL?

The DISTINCT keyword in MySQL is used to return only distinct (different) values within a query. When used, it ensures that duplicate records are eliminated from the result set. Internally, MySQL processes the DISTINCT keyword by performing a sort operation on the values being selected, allowing it to identify and remove duplicates before returning the result.

When you execute a query with DISTINCT, MySQL groups the results based on the selected columns and ensures only unique combinations are included in the final output. This behavior is crucial for ensuring data integrity and offering a clearer view of the data at hand.