Make a separate table for each set of related attributes, and give each table a primary key. Each field contains at most one value from its attribute domain.
为每个相关属性的集合创建一个单独的表，并为每个表指定一个主键。每列最多包含一个来自其属性域的值。
Design attribute domain integrity. Considerations include CHECK constraints, data types, and nullability.
设计域完整性属性。考虑CHECK约束，数据类型和是否非空。
Design attribute domain integrity. Considerations include CHECK constraints, data types, and nullability.
设计域完整性属性。考虑CHECK约束，数据类型和是否非空。
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