You can add a Data Aggregate Description in a Meta Entity,
Meta Entity Type or in a Meta Data Aggregate. For each Data Aggregate
description entered in the composition of these Entities, you must
then define its characteristics in the Data Aggregate Description and Component
Usage sections. A Data Aggregate is a description which
contains other descriptions and Data Elements or descriptions only.
Data Aggregate Description
For a Data Aggregate which is added as the root of the composition
in a Meta Entity, you only have to specify its name and label. But
for each sub Data Aggregate descriptions, you must specify its usage
too.
- Name
- Enter the name of the Data Aggregate description or Data Element
inserted or selected in the composition tree.
- Label
- Enter a label for the Data Aggregate description.
.
Component Usage
- Minimum Cardinality
- Enter a numeric value to indicate a minimum cardinality. The default
value is 0, which means that the description is not mandatory.
- Maximum Cardinality
- Enter a numeric value to indicate a maximum cardinality. The default
value is n for unbounded.
- This value indicates the maximum or equal number of occurrences
allowed in a User Entity for this current description. The value entered
in the maximum cardinality field must be higher than the value in
the minimum cardinality field. If it is not, an error will be displayed
in your User Entity.
- Checks are set on the values entered in these fields. For example,
if you define by error a minimum cardinality which is in fact higher
than the maximum cardinality, the description icon is marked erroneous
in the composition tree. If you move your cursor over the icon, you
can read in a tooltip that the maximum cardinality must be higher
than or equal to the minimum cardinality.
- Identifiers
- This table is used to specify the fields which will be set as
identifiers in the Data Aggregate description, that is to say, defined
as the key. It means that in a User Entity you cannot call more than
one description with the same combination of identifiers. Click + to
add a field, or click a field and then − to
remove a field from the table. Click the up or down buttons to modify
the list of identifiers in the table.
Important: The cardinality
of these identifiers must be (1-1). A presence check will be performed
on this field.
- Unique
- In this table, you can add fields that you set as unique. It means
that in two different descriptions, it is not possible to find two
fields unique with the same value. As you did for the identifiers,
click the + to add a field in the table, or
click a field and then − to remove a field
from the table. Click the up or down buttons to modify the list of
unique fields in the table.
- Sorts
- This table is used to give the order of the descriptions in the
User Entity. The descriptions will be sorted in the order given in
this table.
- Descending
- Check this box to get the descriptions sorted descending in the
descending order. Clear the box if you prefer an ascending order.