1) An ERM is dependent on the database type.
2) The word “entity” in the ER model corresponds to a table.
3) The Crow’s Foot model is less implementation-oriented than the Chen model.
4) The ER diagram represents the conceptual database as viewed by the end user.
5) The ER model refers to a specific table row as an entity instance.
6) In both the Chen and Crow’s Foot models, an entity is represented with a rectangle containing the entity’s name.
7) The ER model refers to a specific table row as an entity occurrence.
8) Attributes are types of entities.
9) In the original Chen model, each attribute is represented using an oval with the attribute name connected to the entity with a line.
10. Software vendors have adopted the Chen representation because of its compact representation.
11) Attributes have a domain that specifies the data type of the attribute.
12) Attributes cannot share a domain.
13) In an ER diagram, primary keys are usually bolded.
14. Ideally, a primary key is composed of several attributes.
15. A composite identifier is a primary key composed of more than one attribute.
16. All attributes are either simple or composite.
17) All simple attributes are also single-valued.
18) In the Chen model, a multivalued attribute is connected to the owning entity with a double line.
19) The DBMS can easily handle multivalued attributes.
20) Derived attributes are stored in a special database table.
21) A relationship is identified by a name that describes the relationship.
22) Cardinality expresses the minimum and maximum number of entity occurrences associated with one occurrence of the related entity.
23) In Chen notation, there is no way to represent cardinality.
24) Connectivities and cardinalities are established by business rules.
25) A weak relationship exists if the primary key of the related entity contains at least one primary key component of the parent entity.
26) You should always load data from the 1 side of a 1:M relationship.
27) A weak entity has a primary key that is partially or totally derived from the parent entity in the relationship
28. The existence of a mandatory relationship indicates that the minimum cardinality is 0 or 1 for the mandatory entity.
29) Relationships operate only in one direction.
30. A recursive relationship is one in which a relationship can exist between occurrences of the same entity set
