Property/Field
A property/field is an object that carries data directly inside an entity/table. The same object is called a property in the logical model and a field in the physical model, with the same meaning and the name changes with the model hierarchy. This page describes the conceptual boundaries of both and the design responsibilities of the fields; see Attributes/Field Actions for new and maintenance operations, and Attributes/Field Attributes for the values of each attribute.
Concepts and Correspondence
| Model Hierarchy | Object Name | Description |
|---|---|---|
| Concept Model | — | This hierarchy expresses business concepts as business objects without refining them into properties, see Business Objects |
| Logical Model | Properties | Describe the information items that the entity needs to record, named according to the business meaning, without binding to a specific database type |
| Physical Model | Fields | The landing form of logical properties on the target database, including physical storage properties such as data type, length, constraints, etc. |
The Chinese name of the field is used for business expression, and the field name is used to generate DDL, which are maintained separately. When the logical model is converted to a physical model, the properties and fields are synchronized according to the corresponding relationship.
Design Responsibilities for Fields
| Responsibilities | Description | Maintenance Location |
|---|---|---|
| Identity Record | Uniquely identifies a row of data as a primary key or a member of a primary key | Field Editor, Index |
| Establish Association | Host the parent table primary key as a foreign key, forming a relationship | Relation Action |
| Expressing Business Meaning | Explanation of Value Meaning by Chinese Name and Business Definition | Field Editor Property Bar |
| Constraint Values | Limit Values by Checking Constraints, Enumerating Codes | Attributes/Field Attributes |
| Landing standards | Reference data standards, inheriting the technical properties of the standard | Data standards |
| Description Physical Storage | Data Type, Precision, Non-empty, Defaults, etc. | Field Editor Property Bar |
Field rendering in the model
| Rendering Location | Description |
|---|---|
| ER Diagram | Fields are displayed dynamically within entities/tables, and display fields and data types are controlled by Display Layout |
| Field Editor | Centralized maintenance of individual table fields and their properties |
| Index and Relationship | Fields appear as primary keys and foreign key members in Index and Relationship Properties |
| DDL | Field names, types, and constraints write table-building statements, see Generating DDL |
Division of labour with adjacent pages
- To add, move, translate fields, or bulk edit, see Properties/Field Actions.
- To set properties such as constraints, enumeration, increment, role type, and so on, see Attributes/Field Attributes.
- See Entity/Table Actions for how to create and manage tables that belong to a field.
The field is the finest management granularity in the model. Its name, type and standard reference will directly affect the result of generating DDL. The scope of influence should be confirmed before modification.