它们由逻辑数据模型转换而来，其中实体和关系转换为表、列、主键、外键以及约束。

They are transformations of logical data model where the entities and relationships are transformed into tables, columns, primary keys, foreign keys, and constraints.

youdao

那么，让我们为每个实体Bean来定义约束吧。

So, let's define the constraints for each of our entity beans.

youdao

对于每个实体Bean，我们仅需增加一个Groovy脚本来定义合适的约束。

For each of our entity beans, we simply need to add a Groovy script to define the appropriate constraints.

youdao