Also, DB2 cannot use random order index columns as part of a sort merge join.

另外，DB 2无法在排序合并合并连接中使用随机顺序的索引列。

youdao

Join plan directives that force optimizer to use the designated join method to join tables in the query, either nested loop join, sort merge join, or dynamic hash join.

连接计划指示，强制优化器使用指定的连接方法来连接查询中的表，要么是嵌套循环连接、分类合并连接，要么是动态哈希连接。

youdao

A hash join is usually faster than a sort merge join since there is no sort operation involved.

哈希连接通常比分类合并连接快，因为它没有涉及到分类操作。

youdao