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oracle adf workshop


Creating Entity Objects (continued)

Mandatory: This is selected by default for columns with NOT NULL constraints.

Discriminator: Select if this is a discriminator column for a polymorphic entity object.

Change Indicator: Select if the column is a change indicator, such as a timestamp, to be used to indicate that a row has been changed by another transaction (if no columns are specified as change indicators, ADF BC does a column-by-column comparison).

Selected in Query: This indicates whether the attribute participates in the SQL query for this entity object.

Primary Key: This is selected by default for columns with PRIMARY KEY constraints.

Unique: Specify whether the corresponding table column is to be generated with a UNIQUE constraint.

Queryable: Specify whether this attribute can occur in the WHERE clause of a view object (selected by default except for LOBs).

Effective Date: The attribute is either the start or end date of a date range for which the entity row is effective (used for a point of time snapshot to answer such questions as what an employee’s salary was on January 30, 2004.)

History Column: Select to use this column to log changes to the database. You can log changes only if you have implemented JAAS authentication, the selected attribute is persistent, you have not selected Primary Key, Mandatory, or Discriminator, and the attribute is Char, Character, String, Date, Timestamp, or Number. After you have selected History Column, you can choose the history column type (created on or created by for a Date or Timestamp attribute, created by or modified by for a Char, Character, or String attribute, or version number for a Number attribute.)

Updatable: You can enable the attribute to always or never be updatable, or enable it to be updated only before the entity is first posted (while new).

Refresh After: Specify whether to retrieve the value from the database after an update or insert.

Database Column: This indicates the name and SQL data type of the column to which the attribute is mapped.

Java: Specify whether to create Java files to implement custom logic for validation and default values in the entity class or to override base class methods. You can opt to create Java files for any or all of the entity collection class, the entity object class, or the entity definition class. Otherwise, only XML files are generated.

Generate: It enables you to create a default view object and application module from this entity object.

Summary: It presents a summary of the selected options.