You cannot use multiple external tables in the main query.

不能在主查询中使用多个外部表。

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Find the package and section information for the main query from the catalog tables.

从目录表中查找主查询的包和片段信息。

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Find the package and section information for the main query from the catalog tables.

从目录表中查找主查询的包和片段信息。

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