如何使用传统关系数据库复制核心数据模型？
我的应用程序使用核心数据和下面的数据模型。但是，我正在切换到具有列和行的标准数据库。谁能帮助我设置这个新的数据库架构？
I have my app using core data with the data model below. However, I'm switching to a standard database with columns and rows. Can anyone help me with setting up this new database schema?
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首先，您需要为每个实体及其属性创建表（请注意，我向每个关系表添加了“id”）：
现在您已经有了描述每个实体的表格，您需要创建描述这些实体之间关系的表 - 与之前一样，表名大写，字段位于括号中：
就是这样！现在，如果您需要将练习添加到例程中，您只需：
对于所有其余关系都适用。
注意：您的核心数据模型具有一对多和多对多关系。如果您想明确强制关系是一对多的（例如，Exercise 只能有 1 个例程），那么您需要将“exercise_id”设置为 RoutineExercises 表的索引。如果您希望允许多对多关系（即每个练习允许有多个例程），则将（routine_id，exercise_id）的元组设置为索引。
First of all you need to create tables for each of the Entities and their attributes (note I added "id" to each of the tables for relationships):
Now that you have tables that describe each of the entities, you need to create tables that will describe the relationships between these entities - as before table names are in capitals and their fields are in parenthesis:
That's it! Now if you need to add an exercise to a routine, you simply:
This will hold true for all the rest of the relationships.
NOTE: Your core data model has one-to-many and many-to-many relationships. If you want to specifically enforce that a relationship is one-to-many (e.g. Exercise can only have 1 routine), then you will need to make "exercise_id" as the index for the RoutineExercises table. If you want a many-to-many relationships to be allowed (i.e. each exercise is allowed to have multiple routines), then set the tuple of (routine_id, exercise_id) as the index.