Final answer:
Defining a new attribute time card field dependent on the Project value in Project Costing involves understanding the schema, creating a field with a foreign key relationship, and managing the data source to filter tasks based on the project selected.
Step-by-step explanation:
To define a new, single attribute time card field with a data source for the Project Costing Task time attribute that is dependent on the Project Costing Project value selected, you'll need to take a systematic approach. First, the Project Costing schema and its entities must be understood, particularly the relationship between Project and Task entities. Attributes are fields that contain data related to entities.
When creating a new attribute, such as a time card field, you need to ensure that the field will store time-related data (e.g., hours worked) and can reference specific tasks within a project. To set up the field to be dependent on a project value, you would likely use a foreign key relationship to the Project entity, so that the time entered in the time card can be associated with the correct project.
The actual implementation of this new attribute can vary depending on the database or application framework being used. For instance, in a SQL database, you would use an ALTER TABLE statement to add the new column to the Task entity. In an application like Microsoft Dynamics or an ERP system, you might use the interface provided for customizing or extending the existing data model.
Importantly, once the new attribute is in place, the data source for this field must be carefully managed. This could involve writing a query that filters available tasks based on the selected project, or setting up a user interface control that updates the available options as projects are selected.