Creating and Editing Entities
- 1 All tabs
- 2 Attributes/Columns tab
- 3 Keys tab
- 4 Relationships tab
- 5 Definition tab
- 6 Note tab
- 7 Where Used tab
- 8 User-Defined Mappings tab
- 9 Constraints tab
- 10 Dependencies tab
- 11 Permissions tab
- 12 Naming Standards tab
- 13 Data Lineage tab
- 14 Security Information tab
- 15 Attachment Bindings tab
- 16 Notes
- 17 See Also
Entities are the starting point for a data model. The relevant properties or characteristics of an entity are represented by attributes. Entities are basically an aggregation of attributes, and therefore we recommend that you are clear on the scope and purpose of each entity before worrying about its attributes. Once you have thought carefully about an entity's purpose, then its attributes should become apparent.
Supertypes and subtypes are one of the more advanced topics in entity-relationship modeling. For more information, see Creating Subtype Cluster Relationships.
ER/Studio Data Architect represents entities in the Data Model Window as boxes. In the default display mode, entity names appear above the entity boxes with the primary key and non-key attributes showing inside the entity box, separated by a line.
ER/Studio Data Architect entity boxes have either square or rounded corners. Entity boxes with square corners are independent entities and those with rounded corners are dependent entities. In IDEF1X, an entity becomes dependent when it becomes the child entity in any identifying relationship. Based on this simple rule, ER/Studio Data Architect automatically maintains entity type. An entity is always created as an independent entity because it starts with no relationships attached to it. An entity remains independent until it becomes a child in any identifying relationship.
To create a new entity:
- In the Data Model Explorer expand the Logical Main Model
- Right-click the Entities node, and then click New Entity.
To define or edit entity details:
- Double-click the entity to launch the Entity Editor.
- Define the entity as required and then click OK.
The following helps you complete the options of the Entity Editor:
Logical Only: When selected, the entity will not be implemented as a table when generating a physical model, and will be ignored when comparing the logical model with a physical model.
Add, edit, or delete attributes/columns. You can also change the list order of the attributes/columns, which changes their corresponding placement in the entity/table. You can also add an attribute/column to the primary key for the entity/table. The tabs at the bottom of the Attributes/Columns tab apply only to the attribute/column selected. For more information, see Creating and Editing Attributes and Columns.
Add, edit, or delete alternate keys and inversion entries. Provides access to the Key Editor. For more information, see Creating and Editing Keys.
View any Relationships, if any, that exist between the entity/table and any other entities./tables. Information about the relationships include the relationship type and the Foreign Keys. On this tab, you can double-click a related entity/table to open the entity/table editor for that entity/table. For more information, see Creating and Editing Relationships.
Enter or edit a definition for the entity/table.
The notes added here are included as part of the HTML report when you generate a report for the model. You can format the notes using standard HTML tags. For information about reports, see Generating RTF and HTML Model Reports.
Where Used tab
Shows which logical and physical models and submodels implement the entity. Also shows any existing user-defined mappings (UDM) for this entity/table. UDMs tie data together that can be conceptually related but not necessarily with concrete transactional relationships. UDMs are not used when comparing data models or when generating SQL.
ER/Studio Team Server data sources related to the current model are listed under the Related Data Sources node. A catalog and/or owner, if available, are listed as properties underneath the data source. Related data sources are only visible if you are logged in to ER/Studio TS. Similarly, related data sources are only visible for models in a Repository diagram and is synchronized in ER/Studio Team Server.
Use the Definition tab of the User-Defined Mapping editor to describe the relationship between entities that is created using user-defined mappings. For more information, see Associate Similar Objects Using User-Defined Mappings.
User-Defined Mappings tab
Shows any existing user-defined mappings (UDM) for this entity/table. UDMs tie data together that can be conceptually related but not necessarily with concrete transactional relationships. UDMs are not used when comparing data models or when generating SQL. Use the Note tab to describe the relationship between entities that is created using user-defined mappings. For more information, see Associate Similar Objects Using User-Defined Mappings.
Add, modify, or delete a constraint. Check constraints are used to ensure the validity of data in a database and to provide data integrity. For more information, see Enforcing Data Integrity Using Check Constraints.
Displays views that use the attributes/columns of current entity/table. For information on Views, see Creating and Editing Database Views.
Sets access roles and user permissions for the entity/table. Keep in mind that the more specific permissions are, the more time you may have to spend maintaining and updating them. The Roles and Users must be previously assigned to appear in the Entity/Table Editor. For more information, see Creating and Editing Database Roles and Creating and Editing Database Users. For more information, see Granting and Revoking Permissions to Modify Database Objects.
- Column Permissions: Sets access roles and user permissions for the attribute/column. Keep in mind that the more specific permissions are, the more time you may have to spend maintaining and updating them.
Naming Standards tab
Controls User and Object Permissions to modify the affected item. When a Naming Standards Template is bound to an object, then that template is used instead of the Naming Standards Template selected in the Naming Standards Utility or the Generate Physical Model utility. This allows you to apply different naming standards to different objects when portions of a model require different versions of a standard. For example, some objects already exist in the database and you do not want to apply a newer naming standard to them. The Freeze Names option when selected prevents any naming standards applied from changing the name of the entity selected. For more information, see Enforcing Naming Standards Using Naming Standards Templates.
Data Lineage tab
Maps the flow of data from source to target entities and attributes, or tables and columns, in the model. The Data Lineage tab appears in the entity and table editors. At the attribute level, you can add transformation logic for source/target attribute mapping. If a Data Movement Rule has been bound to an entity, you can override the bound value from this tab by double-clicking the row containing the Dave Movement Rule and then entering the new value in the Value Override Editor. For more information, see Data Lineage Workflow.
Security Information tab
Displays the current security information as defined in the Data Dictionary. You can add or edit security reporting information in by double-clicking the field you want to change. To set the model-wide default value for a property, go to the Data Dictionary tab and expand the Data Security Information Node. For more information, see Enforcing Security Using Data Security Types and Properties.
Attachment Bindings tab
Bind an external piece of information, or attachment to the entity. You can also remove an attachment from an object, override an attachment binding's default value, or change the position of a bound attachment. To override the value of the attachment you have moved to the Selected Attachments grid, double-click the Value field of the target attachment. ER/Studio Data Architect opens the Value Override Editor or a list depending on the attachment datatype. Attachments are created in the Attachments folder of the Data Dictionary and must be applied to the entity before they will display on this tab. For more information, see Attaching External Documents to the Data Model.
- When you create an entity, it automatically appears as an independent entity with square corners. As relationships are drawn associating the entity with others, ER/Studio Data Architect automatically maintains its status as an independent or dependent entity.
- You can name entities as you add them by using on-screen editing. Either type a name for an entity immediately after adding it to the diagram, or press the SHIFT key, click the default entity name to enable the entity name field, and then type a name. Click the diagram background to save the name and deactivate on-screen editing. For information on entity naming rules and conventions, see [[Best Practices]
- The status bar at the bottom right of the application window displays the number of entities in the selected model.
- You can specify naming rules, such as maximum length, case, and synchronization level between entities and tables on the Logical and Name Handling tabs of the Options Editor, which you can access by choosing Tools > Options > Logical.
- You can specify the display order of the attributes and primary keys of any entity on the Display tab of the Options Editor, which you can access by choosing Tools > Options > Logical.
- You can customize the information that pops up when you hover the mouse over an entity by selecting an option from the list that appears when you choose View > Cursor Popup Help Options > Entity Help.
- By default, ER/Studio Data Architect automatically fits entities and views to display all content selected. However, you can resize any entity to any size by selecting the entity and then dragging the size handles. You can make global changes to how entities display by right-clicking the model, and selecting Diagram and Object Display Options. Then you can choose the display options desired in the Entity and View tabs of the Diagram and Object Display Options editor.
- For information on arranging entities in the Data Model Window, see Changing Data Model Layout.
- For information on changing the colors of entities, see Overriding Color and Font Settings for a Specific Object.