The entity integrity rule states that:
A) no primary key attribute can be null.
B) referential integrity must be maintained across all entities.
C) each entity must have a primary key.
D) a primary key must have only one attribute.
A
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Which of the following is true of the emission charges approach?
A) The emission charges approach is simply to charge the polluter a variable fee based on every unit of pollutant discharged. B) The firms paying the charges will continue to emit pollutants that will be easy to clean up with the fees collected. C) Due to the value of the charge, this approach prevents pollution in the first place. D) It is difficult to monitor every discharge of the pollutant and calculate the amount for each unit of the various pollutants.
The fact that conflict occurs, even though it is managed carefully, is never a good thing
Indicate whether the statement is true or false.