我们在实践中发现，除非一个项目是完全空白的，否则，除了进行自上而下的分析外，还需对预先存在的代码和业务逻辑进行自下而上的分析。

In practice, we find that unless a project is entirely green field, in addition to a top-down analysis, there is a simultaneous bottom-up analysis of pre-existing code and business logic.

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但是，考虑到众所周知统一俄罗斯党精于选举，许多分析家不确信能够发生自下而上的变革。

But given United Russia's reputed skill at engineering elections, many analysts are not sure that change can come from the bottom up.

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RDA可用于采取自下而上或自上而下的方式开发数据模型，允许分析已有数据库和通过对已有数据资产的反向工程开发数据模型。

RDA can be used to develop data models in either a top-down or bottom up manner, allowing analysis of existing databases and development of data models by reverse engineering of existing data assets.

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