Specify the column on one-to-many

最新推荐文章于 2025-12-07 12:18:51 发布
原创 最新推荐文章于 2025-12-07 12:18:51 发布 · 776 阅读 · 0 ·
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#class #schema #sql #table #file

本文介绍了如何正确配置对象关系映射（ORM），确保父类与子类之间的关系正确建立。通过指定属性引用而非使用默认标识符，可以实现更精确的数据关联。

If we want the relatioship is TestParent.testNo = TestChild.testNo, do not use the identity column "id".

We should specify the columns in mapping file, such as:

 

 

<key property-ref="columnName"> is for Parent object

<column name="columnName"> is for Child object

 

If do not specify the property-ref, the sql would be:

this.ID = this.child.columnName.

 

If specify the property-ref, the sql would be:

this.columnName = this.child.columnName

 

 

 

 

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