Understanding the Model Layer - Oracle ADF 11gR2 Development Beginner's Guide - page 82

Expression : This seing lets you default the atribute to an expression. Groovy
expression language is used to define the expression. Groovy is a Java-like language
used for scriping.
Refresh Expression Value : This is the condiion provided to recalculate the
expression value.
SQL : This seing lets you default to the output of an SQL query.
Polymorphic Discriminator : Checking this opion makes the atribute the
discriminator column, which is used to idenify the type of the enity object
we already knew we are working with and it also ideniies the enity object
that is extended from a parent enity object.
Efecive Date : This is related to the Efecive Date funcionality to get the
informaion at a paricular ime. Someimes informaion may change during a
single day, so to keep track of the change in informaion, we use this opion.
For an efecive date, you would need a column represening a start date,
an end date, a sequence, and a sequence lag. These atributes are mapped
to the corresponding available opions.
Start Date : This is the attribute with a start date
End Date : This is the attribute with an end date
Sequence Flag : This is the attribute mapped for a sequence flag
Sequence : This is the attribute mapped for the sequence
Updateable : This sets the atribute as updateable. If this is not checked, then the
atribute value cannot be updated and trying to update it will result in an excepion.
The following opions will deine when the atribute should be updateable:
Always : This option defines that the attribute is always updateable.
While New : This option defines that the attribute is updateable only
when the attribute is newly created or initialized.
Never : This option defines that the attribute can never be updated.
The attribute will be displayed as read-only in the UI.
Persistent : This opion deines if the atribute value should be stored in
the database.
Transient : This opion deines that the atribute value is not persisted to
the database and is used to calculate the values in the middleware layer.
Mandatory : This opion sets the atribute as required. If the atribute is not
given a value, then ADF will prompt to provide a value for this atribute.