How EAR diagrams map to Definer records

Overview

EAR diagrams in USoft Definer 11 are automatically synchronised in both directions with records in USoft Definer for:

• Data contents of the Business Object that the EAR diagram is for.
• Tables.
• Columns.
• Relationships.
• Relationship columns.

As a result of this 2-way synchronisation:

• When you open or re-open the EAR diagram from the Business Object, the diagram is automatically adjusted to the latest changes you made in USoft Definer for these objects. For example, if you added a Table in Definer, you will see a new table box for it in the diagram. USoft makes an effort to place this table box in a location on the canvas that is helpful, but you will probably want to drag  the box to another position to get a better-looking diagram.
• When you add, change or drop objects in the EAR diagram, at the time when you exit the diagram, changes will automatically be to the various Definer records. These records will be inserted, updated or deleted on the basis of the latest version of the diagram. If you do not like the result, you can still rollback the transaction after diagram exit. If you do like the result, you need to Save it.

Viewing an EAR diagram's properties

EAR diagrams contain 3 types of drawing objects that map to USoft Definer objects:

* Attribute items are lines of text displayed within table boxes, each with a coloured item to its left.

** A connector line is a line connecting 2 table boxes.

To understand the rest of this article, in an EAR diagram, you need to view all the properties of a drawing object:

1. Select the object in the drawing (table box, attribute item or connector line). Do this by clicking on it.
2. Click on the Properties icon near the right-hand end of the icon ribbon across the top of the canvas:

3. See that a Properties list opens for the object on the right-hand side.

Data contents of the Business Object

An EAR diagram created in USoft Definer 11 is connected to a Business Object.

A Business Object has Data Contents: a collection of Tables, Relationships, Domains and Temporary Content. Each of the items in this collection may or may not be Owned by the Business Object. An item can be Owned by at most 1 Business Object.

You can view this Data Contents by pressing the Structure button in the Business Object window.

EAR diagrams only interact with the Table items in the Business Object's Data Contents, not with the other items.

EAR diagrams do not interact with the Owned (Yes/No) property of Tables. To the EAR diagram, it makes no difference whether a Table is Owned or not.

The collection of Tables depicted in the EAR diagram is automatically synchronised with the list of Tables in the Business Object’s Data Contents in both directions:

• When you open or re-open the EAR diagram from the Business Object, the diagram is automatically made to contain all the tables in the Data Contents and no other tables. If a table was added to the Data Contents since the last time the diagram was open, USoft makes an effort to depict the table in a location on the canvas that is helpful, but you will probably want to drag the box to another position to get a better-looking diagram. The diagram is automatically made to depict all the relationships defined between the tables in the Data Contents, independently of whether these relationships are listed or not as being Data Contents items in the Business Object.
• When you add a table to the EAR diagram, at the time when you exit the diagram, the table is added to USoft Definer and also added to the list of Tables in the Business Object's Data Contents.
• When you remove a table from the EAR diagram, at the time when you exit the diagram, the table is deleted from USoft Definer and therefore also from the list of Tables in the Business Object's Data Contents.

Tables

Tables: Definer-to-diagram

A table in Definer with Table Name = TOUR_PROGRAMME and Object Name = "Tour programme” in Definer maps to an EAR entity box with these properties:

In the diagram, the “Object name” also appears in the blue header bar of the table box and can be edited there after double-click.

In the diagram, the "Table name” property cannot be edited.

A Supertype setting for a table in Definer maps to a subtype-to-supertype connector line connecting the subtype box and the supertype box in the diagram. The line is arrow-shaped. The arrow points from the subtype to the supertype.

Tables: Diagram-to-definer

A table box newly added to an EAR diagram maps to a Table record in Definer.

Because Definer identifies a Table alternatively by its Table Name, Abbreviation, Object Name, or Object Name Plural, if you draw a table box with "Object name” = "Tour programme”, a record is created with the following values:

After creation, if you change "Object name” in the diagram, this will change "Object Name” in Definer. The other 3 columns are not affected by diagram change after creation.

In the diagram, the "Table name” property cannot be edited.

A subtype-to-supertype connector arrow between 2 table boxes in an EAR diagram maps to the Supertype column in the Definer record for the subtype being set to the supertype.

Columns

Columns: Definer-to-diagram

A TOUR_TYPE column in Definer in table TOUR_PROGRAMME with Prompt = “Tour type” maps to an EAR attribute item with these properties:

In the diagram, the “Object name” also appears as the display name of the attribute item for column TOUR_TYPE within the text box for table TOUR_PROGRAMME.

In the diagram, the "Column name” property cannot be edited.

The following non-key properties of EAR attributes are affected by Definer column attributes:

In the diagram, Key is set to Yes if the column has Key = 1, to No otherwise. The Key setting also translates into the attribute item being displayed either with a coloured key symbol (Key = Yes) or with a coloured rectangle (Key = No).

In the diagram, Mandatory is set to Yes if the column has Mandatory = Yes, to No otherwise. This setting also translates into the attribute item being displayed either with a red symbol (Mandatory = Yes) or a green symbol (Mandatory = No).

In the diagram, "Input allowed” is set to Yes if the column has Input Allowed = Yes, to No otherwise. This setting also translates into the attribute item being displayed either normally (Input allowed = Yes) or with a dotted outline rectangle (Input allowed = No).

In the diagram, "Template domain” is set to the column's Template Domain. This, in turn, is automatically derived from the characteristics of  the Domain that the column is based on.

In the diagram, "Default value” is set to the column’s Default Value, or to the Default Value of the column's domain if that domain has a Default Value and the column does not have a Default Value of its own.

In the diagram, the "Value list” property cannot be edited. It is set to the list of Allowed Values of the column's domain.

Columns: Diagram-to-Definer

An attribute item newly added to a table box in an EAR diagram maps to a Column record in Definer.

Definer identifies a Column by the combination of Table Name and Column Name. If you create a new attribute item with "Object name” = "Tour type” in the table box for the TOUR_PROGRAMME table, a Column record is created with the following values:

After creation, if you change "Object name” in the diagram, this will change "Prompt” in Definer.

You cannot edit Column Name in the EAR diagram. You also cannot edit Table Name (for the surrounding table box) in the EAR diagram.

The following non-key column attributes in Definer are affected by EAR diagram attribute items:

If the EAR diagram has Key = Yes, then for the column in Definer, Key is set to “1”.

If the EAR diagram has Key = No, then for the column in Definer, Key is initially set to "No” if the column did not exist in Definer. After creation, Key = 2, 3…. settings do not interact with the EAR diagram.

In EAR diagrams, for an attribute, you can only select one of the standard Template Domains. You cannot select any other domains. For the column in Definer, Domain Name is initially set to the selected "Template domain” in EAR if the column did not exist in Definer. After creation, you can set Domain Name in Definer to anything you like. If that choice changes the derived Template Domain, that will reflect in the diagram the next time you open the diagram.

If the EAR diagram does not have a value for "Default value”, Definer is not affected. If it has, then the column's Default Value attribute is set to that value, overwriting any existing other value.

Parent-child relationships

Parent-child relationships: Definer-to-diagram

A TOUR_PROGRAMME IS FOLLOWED BY TOUR parent-child relationship in Definer maps to an EAR relation line between the "Tour programme” table box and the "Tour” table box. with these relation properties:

The "Object name” is also displayed as a text accompanying the relation line.

In the diagram, the "Parent role” property cannot be edited.

The following non-key properties of EAR attributes are affected by Definer Relationship attributes:

In the diagram, "Max children = 1” is set to Yes if the relationship has Maximum Children = 1, to No otherwise.

In the diagram, the first 3 properties (the 3 Yes/No flags) also affect the symbols shown at either end of the relation line at the point where the line connects to the table box. These symbols represent cardinality. The cardinality of a parent-child relationship depends on the combination of Yes/No settings for these 3 properties.

Parent-child relationships: Diagram-to-Definer

A relation line newly added to an EAR diagram with Is Subtype = No (the default) maps to a Relationship record in Definer and to one or more corresponding Relationship Column child records.

Definer identifies a Relationship by the combination of Parent Object, Child Object and Parent Role. If you draw a new relation line from the "Tour programme” to the "Tour” table box, if you do not make any explicit property settings, then a Relationship record is created with the following values:

* HAS is the default. If you type a text string in the text box accompanying the new relation line, then the all-uppercase version of this text is used as Parent Role value instead.

After creation, you cannot edit Parent Role in the EAR diagram.

A Relationship must have at least 1 Relationship Column record. A Relationship Column record expresses how a primary key column in the parent table maps to a foreign key column in the child table.

The diagrammer knows about primary key columns but not about foreign key columns. When an EAR parent-child relation is newly created, USoft assumes that it is acceptable for the foreign key column (in the child) to have the same column name as the corresponding primary key (in the parent). Drawing the EAR relation results in an extra foreign key Column record in Definer for each of the primary key columns, if that foreign key column does not yet exist. Assuming that a Tour Programme's primary key is (Destination, Tour type) and the foreign keys do not yet exist, the EAR relation causes 4 records to be created, as follows:

2 Column records :

2 Relationship Column records:

So far, this discussion has been about identifying columns (key columns) for the Relationship. In addition, the following non-key relationship attributes in Definer are also affected by EAR parent-child relations:

* If the EAR “Max children = 1” = No, the Definer "Maximum Children” attribute is not affected.

Supertype-subtype relationships

Supertype-subtype relationships: Definer-to-diagram

If a Definer table STAFF has Supertype = PERSON, this setting maps to an EAR relation line between the table boxes for PERSON and STAFF with an arrow-shaped look. The arrow points from the subtype to the supertype (from the STAFF box to the PERSON box).

The EAR relation is given the following properties:

In the diagram, the "Object name” is also displayed as a text accompanying the relation line. You can erase this text if you like.

In the diagram, the "Parent role” property cannot be edited.

The "Object name” and "Parent role” properties do not map to anything in Definer.

In the diagram, the first 3 Yes/No flags are set to No simply because these properties have no meaning for subtype-supertype relationships (only for parent-child relationships).

Supertype-subtype relationships: Diagram-to-Definer

A relation line newly added to an EAR diagram with Is Subtype = Yes maps to a Table record in Definer with Supertype set to a (non-null) value.

When the EAR supertype-subtype relation is newly created, USoft makes sure that a subtype table with the same primary key as the supertype is created if it does not already exist in Definer.