ER Model

Which one of the following is used to represent the supporting many-one relationships of a weak entity set in an entity-relationship diagram?

In E-R model, Y is the dominant entity and X is subordinate entity

In an Entity-Relationship (ER) model, suppose R is a many-to-one relationship from entity set E1 to entity set E2. Assume that E1 and E2 participate totally in R and that the cardinality of E1 is greater than the cardinality of E2.
Which one of the following is true about R?

Which symbol denote derived attributes in ER Model?

An ER model of a database consists of entity types A and B. These are connected by a relationship R which does not have its own attribute. Under which one of the following conditions, can the relational table for R be merged with that of A?

Consider the following Relationship Entity Diagram(ERP)


Which of the following possible relations will not hold if the above ERD is mapped into a relation model?

Consider an Entity-Relationship (ER) model in which entity sets E1 and E2 are connected by an m : n relationship R12. E1 and E3 are connected by a 1 : n (1 on the side of E1 and n on the side of E3) relationship R13.

E1 has two single-valued attributes a11 and a12 of which a11 is the key attribute. E2 has two single-valued attributes a21 and a22 of which a21 is the key attribute. E3 has two single-valued attributes a31 and a32 of which a31 is the key attribute. The relationships do not have any attributes.

If a relational model is derived from the above ER model, then the minimum number of relations that would be generated if all the relations are in 3NF is _______.

An aggregation association is drawn using which symbol?

Given the basic ER and relational models, which of the following is INCORRECT?

Consider the following ER diagram

Which of the following is a correct attribute set for one of the tables for the minimum number of tables needed to represent M, N, P, R1, R2?