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

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。

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You can use the document() function to create indices or tables of content that span multiple files.

可以用 document() 函数来创建涉及多个文件的索引或目录。

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