A allows you to track the history of attribute values

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A) Allows you to track the history of attribute values, relationships, and/or entire entities Which of the following is a logical constraint that could result from considering how time impacts the storage of data? A) End Date must be before the Start Date. B) An ASSIGNMENT may only refer to a COUNTRY that is valid at the Start Date of the ASSIGNMENT. C) Dates have value only with a time component. D) ASSIGNMENT periods can overlap causing the database to crash. B) An ASSIGNMENT may only refer to a COUNTRY that is valid at the Start Date of the ASSIGNMENT.
In an ERD, it is a good idea to group your entities according to the expected volumes. By grouping high volume entities together, the diagrams could become easier to read. True or False?
How do you know when to use the different types of time in your design?
If you are tracking employment dates for an employee, do you need to have an "End Date" attribute?
C) Yes, if the company wants to track multiple start dates and insure that multiple employment dates for an employee do not overlap. When you add the concept of time to your data model, you are: A) Adding complexity to your model. B) Just changing the model, but this does not change the complexity of it. C) Simplifying your model. D) None of these answers. A) Adding complexity to your model.
What is the benefit to the users of a system that includes "time"; e.g. Start Date and End Date for Employees?

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