Setting join_algorithm Respects Specified Order

Why it matters

This feature ensures that the join algorithm chosen by the user via the join_algorithm setting is honored in the order specified. It addresses situations where ClickHouse previously did not strictly follow the set join algorithm preference, giving users more control over join processing strategies which can impact query performance.

How to use it

Users can configure the preferred join algorithm by setting the join_algorithm parameter in their query or session settings. For example, use SET join_algorithm = 'hash' or SET join_algorithm = 'merge' to enforce a specific join strategy.