one-to-one relationship <DAO definition>
内容
one-to-one relationship
An association between two tables in which:
| ? | The primary key value of each record in the primary table corresponds to the value in the matching field or fields of one and only one record in the related table. |
| ? | The primary key value of each record in the related table corresponds to the value in the matching field or fields of one and only one record in the primary table. |