Data description in a Meta Entity (Type) or Meta Data Aggregate
You can add a data description in a Meta Entity, Meta Entity Type, or Meta Data Aggregate. You must indicate its characteristics in the section that opens in the Composition tab. Each description line corresponds to a data item (a field) that will contain a value in the User Entity. For each data description, you must indicate a format, values, and intervals.
Component Usage
- Minimum Cardinality
- Enter a numeric value to indicate a minimum cardinality. The default value is 0, which means that the data is not mandatory in the User Entity.
- Maximum Cardinality
- Enter a numeric value to indicate a maximum cardinality for the data in the User Entity. The default value is n for unbounded.
The value of the Maximum cardinality field must be higher than the value of the Minimum cardinality field. If it is not, an error will be displayed in the User Entity.
- Value Control
- This option is available on data aggregate descriptions and data descriptions. If you check it, only the values that are indicated in the Allowed values or the Intervals table will be controlled.
Data description
- Name
- Enter the name of the data description.
- Label
- Enter a label for the data description.
- Type
- In this field, select the format type of the data in the User
Entity.
Table 1. Format Types Type Comments Date type The date format is based on the SimpleDateFormat Java™ class. Enter a date and time format in the Format field. Click the following link to find date and time patterns. Decimal type Enter a decimal value in the Initial value field (2.0 for example). Then, enter a minimum and maximum decimal value in the Data description detail section. In the User Entity, the data value must be a decimal number that is included between these 2 values. Float type Enter a value with a float Java format in the Initial value field (10e12 for example). Select the type of float in the Capacity field. Integer type Enter an integer value in the Initial value field. Then, enter a minimum and maximum integer value in the Data description detail section. In the User Entity, the data value must be an integer er that is included between these 2 values. String type Enter alphanumeric characters in the Initial value field. You can enter the optional fields that are associated with the String type choice: Maximum length and Case. Byte type Enter a byte value in the Initial value field. Enter a Maximum length in the Data description detail section. Time Stamp type Enter a date with a Java stamp format as the initial value. It consists of a series of digits. Reference type The reference type is used to specify a relation with one or more entities. You must select the linked entities.
- Initial Value
- This field is available for all the format types except the Reference type. Enter a value that will be loaded into the User Entity for the data.
- Data description detail
- The content of this section depends on the format type that is
selected in the Type field of the Data
description section.
- Type Definition
- Format
- This field is available when you select a Date type.
The date format is based on the SimpleDateFormat Java class. Date and time formats
are specified by date and time pattern strings. Example: Date and time format: yyyyMMdd G at HH:mm:ss z.The format automatically applies to the specified allowed values.
- Capacity
- This field is displayed when you select a Float type. It corresponds to the capacity of the float value. It can be a simple float Java value, or a double float Java value.
- Minimum value
- This field is displayed when you select a Decimal type, Integer type, or Time Stamp type. Enter a minimum value for the integer, decimal, or time stamp data in the User Entity.
- Maximum value
- This field is displayed when you select a Decimal type, Integer type, or Time Stamp type. Enter a maximum value for the integer, decimal, or time stamp data in the User Entity.
- Maximum length
- This field is displayed when you select a String type or Byte type. Enter a maximum value for the data that is entered in the User Entity. The maximum for a byte type is one million bytes. You are advised against overloading the memory. The default value is 10000 for a Byte String type. For a string type, it is -1, which means an unlimited number of characters.
- Case
- This field is available when you select a String type. Indicate whether the string that will be indicated in the User Entity will be in uppercase or lowercase.
- Allowed Values
- You can define authorized values for the current data description.
If no value has ever been assigned to the current data description,
the list is empty. If it is not empty, the authorized values and
their labels are displayed. Click + to add
a line in the table. To modify any of the listed values, overwrite
it. To do so, click it and replace the value with a new one. Each
value in the table is identified with
. Click − to remove a line from the table. You can reorder the lines in the table with the direction buttons.
- Intervals
- Click + to add a
line.
In the fields that are displayed, you can enter a minimum value and a maximum value. You can also indicate whether the minimum or maximum value must be included. You can specify a label. The interval that you enter must conform to the length and the class type that are defined for the data description.
When the data takes on a range of values, the range must be described as two values between parentheses, separated by a comma and a space. Inverted square brackets indicate that the value is excluded from the range.
Examples:- [E(), Z()]: from E inclusive to Z inclusive,
- ]E(), Z()[: from E exclusive to Z exclusive,
- ]E(), Z()]: from E exclusive to Z inclusive.
Click the line in the table to refresh.
- Relation type
- This field is displayed when you select a Reference
type. It contains two tables. You can either select the All
types option to indicate that the relation is created
with all entity types, or select one or more entity types. If you
select the User Entity type, click + to
add the Meta Entity it is related to, in the table.
Use the Constraint check box to control the type of error message in the User Entities of this Meta Entity if a relation targets an undefined instance. This box is checked by default. By default, the User Entities that are created from the Meta Entity require the existence of the instance that is the target of the relation. If an undefined instance is entered as the value of a field in the User Entity, an error message will be displayed on the line. If the box is not checked, only a warning will be displayed on the line in the User Entity.