Are Multi-way Joins Actually Useful?

Multi-way joins improve performance by avoiding extra I/Os from multiple partitioning several multi-way join algorithms proposed, and the research results arc encouraulnu. HOW database systems arc not currently using multi-way joins. Practical issues include modifying the optimiz and execution system to support multi-way operators and ensuring robust and reliable performance iL contribution of this work is an implementation and experimental evaluation of multi-way on in PostgreSQL. We provide algorithms that modify the optimizer to cost multi-way joins find create and execute query plans that have inore than two input operators. Experimental results show that multi-way joins arc beneficial for several queries in a production database system and can be effectively exploited by the optimizer, however there arc implementation issues that must be resolved to uttarantec robust performance.