This paper used algorithm of minimum spanning tree to realized multi-join queries of distributed database and provided analyzing method.

本文用最小生成树算法实现了分布式数据库中的多元连接查询，并进行了算法的分析与设计。

youdao

Use UPDATE STATISTICS HIGH if queries have a multi-column indexed defined on join columns or filter columns.

如果查询中有属于多列索引的连接列或过滤列，则使用UPDATE STATISTICS HIGH。

youdao