What are MUST NOT and MUST COVER constraints?
What will be an ideal response?
Both MUST NOT and MUST COVER constraints occur when working with three tables in a ternary relationship. When a MUST NOT constraint occurs, it indicates that one binary relationship of two of the tables contains combinations of values that are not allowed to occur in the ternary relationship. When a MUST COVER constraint occurs, it indicates that one binary relationship of two of the tables contains combinations of values that must all appear in the ternary relationship.
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