Creating a Logical Model
A logical model is created by adding business entities to it, defining relationships among the entities, and defining properties of the entities.
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On the Metadata Insights menu bar, click
Modeling.
The Logical Model tab is displayed by default.
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You can create a logical model from the scratch or can copy an existing model
and use it as a template to create a new model.
- To create a new logical model from scratch, click the Add Logical Model button , and enter a name for the model in the Name field.
- To create a new logical model from an existing logical model:
- Select the required logical model and click the Copy Model icon.
- On the Copy Logical Model pop-up window that is displayed, rename the model in the Name field.
- Select Yes in the Copy Mappings slider to copy all the mappings along with the logical model.
- Click Save.
- Modify details of this logical model, as needed. For more information about modifying a physical model, see Modifying a Logical Model.
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From the Entities palette, select, if you want to use
the Logical entities or the entities defined in the
Glossary to create the model.
Tip: Use the drop-down list in the palette to filter Logical or Glossary entities based on their categories. You can also use the type-ahead filter box below the drop-down list for this.
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Drag the selected entity and drop it to the canvas.
The entity is added to the canvas and its properties are displayed in the PROPERTIES panel on the right side of the page.
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To define a new property of an entity:
- Select the entity and click the PROPERTIES panel.
- Enter these details for the selected entity.
Table 1. Properties table Field Description Name Name of the attribute. For example, age Semantic Type Semantic type of the data for this attribute. Note: When you select the semantic type, the related data type is displayed in the Type field.Type Data type for the attribute. - Click the Add button. The defined attribute, and
its semantic and data type are displayed below the entry
fields.Note: You can delete a property by clicking the Delete icon adjacent to it.
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To create relationship among entities, perform these steps:
Note: An entity can have one-to-one relationship, multiple relationship, and self-relationship.
- Hover the cursor on the entity, drag the mouse and drop it on the entity to which you want to relate it. This links one entity to another in a one-to-one relationship.
- To create self-relationship, hover the cursor on an entity, drag the mouse and drop it on the same entity. It gets linked to itself.
The relationship between entities is indicated by a relationship link. When you hover the cursor on the primary entity, the related entity or entities get highlighted.
Note: As in case of entities, you can add properties to the relationship by using the Properties panel. (See step 5 above) -
To delete an entity or relationship, select it and click the
Delete icon .
If you delete a relationship entity, the related relationship links also get deleted.
- Click Save.
- Name of the logical model
- Default mapping, if any, for the logical model. This is displayed only after you map your logical model to the physical models. For details on mapping a logical model, see Mapping Models - Introduction.
- Last modified date and time of the logical model