RUNSTATS 实用程序用于更新系统目录表中的统计信息，以帮助查询优化过程。

The RUNSTATS utility updates statistics in the system catalog tables to help with the query optimization process.

youdao

通过内部统计数据，我指的是系统目录中的统计数据，优化器可以确定最低成本的查询执行计划。

By internal statistics, I mean the statistics in the system catalogs that the optimizer USES to determine the lowest-cost query execution plan.

youdao

而在关系语言中，这种查询需要进行也许跨越了多个数据表和系统目录表的联接。

In a relational language, such a query would require a join that might span several data tables and system catalog tables.

youdao