This is a more normalized schema than the four-table schema option, so that repeated storage of identical keywords and categories is avoided.

与4表模式选项相比，这种模式更符合范式，所以可以避免重复存储相同的关键词和类别。

youdao

This is a more normalized schema than the four-table schema option, so that repeated storage of identical keywords and categories is avoided.

与4表模式选项相比，这种模式更符合范式，所以可以避免重复存储相同的关键词和类别。

youdao