Join algorithms

Join algorithms are methods used by databases to combine data from two or more tables based on related information they share, like matching customer IDs. They determine how efficiently this combination happens. Common types include nested loop joins, where each row of one table is compared to every row of another; and hash joins, which create a quick lookup table to find matches faster. The choice of algorithm depends on factors like table sizes and data distribution. Effective joins are essential for retrieving meaningful, combined data quickly in complex queries.