当然，原始 XML 数据中存在的名称空间将对如何编写那样的 “转换” 查询造成一定的影响。

Of course, the presence of namespaces in the original XML data affects how you must write such "transformational" queries.

youdao

通过增加一定的CPU时间，可以大大减少这些查询所需的时间。

For an incremental increase in CPU time, the elapsed time for these queries can be significantly reduced.

youdao

但是如果这些表极其庞大，有许多行(比如几百万行)，而且查询具有一定的选择性的话，那么使用索引就好得多。

But if the tables are very large and have many rows (say, a few million rows) and your query fairly selective, it is much better to use indexes.

youdao