5 Questions
What constraint specifies whether an entity in the higher-level entity set must belong to at least one of the lower-level entity sets within a generalization?
Completeness constraint
How is an entity shown as belonging to only one lower-level entity set in an E-R diagram?
Disjoint notation next to the ISA triangle
What does it mean when an entity can belong to more than one lower-level entity set in a specialization/generalization?
Overlapping
How can redundancy be eliminated in a situation where every manages relationship corresponds to a works_on relationship?
By using aggregation
In E-R diagrams, what design decision allows for abstraction of relationships into new entities without introducing redundancy?
Aggregation
Explore concepts related to single-valued attributes, multi-valued attributes, derived attributes, composite attributes, mapping cardinalities, and keys in database management.
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