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Posts: 29
6 days ago
What are MUST NOT and MUST COVER constraints?
Source  Download Study Guide
Database Processing: Fundamentals, Design, and Implementation
Edition: 15th
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6 days ago
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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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6 days ago
Thank you for answering so quickly
wrote...
6 days ago
Was feeling bored, my pleasure Grinning Face with Smiling Eyes
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