VACUUM only works on the main database. It is not possible to VACUUM an attached database file.

译文：VACUUM命令只能工作在主数据库上，不能用来“清扫”一个附加的数据库文件。

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The main database configuration parameter settings that affect the query execution plan were set as follows

影响查询执行计划的主要数据库配置参数设置如下

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Isomerization unit data connectivity components for the main database for retrieval and XML data generation.

数据连接组件主要进行异构数据库的读取和XML数据的生成。

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The online system could not access their records due to the way they were stored on HMRC's main database, she added.

BBC: 'Double standard' on data safety

That goal could prove to be elusive, for Ellison's main database business, still nearly two-thirds of revenue, grows only 3% a year, according to Citigroup.

FORBES: Magazine Article

That goal could prove to be elusive, for Ellison's main database business, still nearly two-thirds of revenue, grows only 3% a year, according to Citigroup (nyse: C - news - people ).

FORBES: Irreplaceable?