在这里使用匹配关键词是因为不是所有列都与UM L属性相关；正如前文介绍过的，添加主键和外键是为了同时映射uml关联。

The match keyword is used here because not every column relates to a UML attribute; as presented earlier, primary and foreign keys are added in order to map UML associations as well.

youdao

除了周日晚上的四重奏和五重奏外，真想不到还有什么能带给我如此的快乐(好，就让我用快乐一词吧)。

I can think of almost nothing that gives me so much - OK, I'm going to use the word - joy as our Sunday evenings of quartets and quintets.

youdao

例如，日期表的外键对于一个文档的每个关键词不会重复。

For example, the foreign key to the date table is not repeated for every keyword of a document.

youdao