CISP CH .8

A primary key is an attribute (or combination of attributes) that uniquely identifies each instance of an entity type.

FALSE

A state is a named property or characteristic of an entity that is of interest to the organization.

FALSE

A ternary relationship is a relationship between instances of two entity types and is the most common type of relationship encountered in data modeling.

FALSE

An aggregation is an association between the instances of one or more entity types that is of interest to the organization.

FALSE

An entity type that associates the instances of only one type and contains attributes that are peculiar to the relationship between those entity instances.

FALSE

An object type is a collection of entities that share common properties or characteristics.

FALSE

Conceptual data modeling is not done in parallel with other requirements analysis and structuring steps during systems analysis.

FALSE

Operations can be classified into four types, depending on the kind of service requested by clients.

FALSE

Projects with purchased models take less time and cost more because the initial discovery steps are no longer necessary, leaving only iterative tailoring and refinement to the local situation.

FALSE

The disjoint rule specifies that if an entity instance of the supertype is a member of one subtype, it can simultaneously be a member of any other subtype.

FALSE

The primary deliverable from the physical data modeling step within the analysis phase is an E-R diagram.

FALSE

A relationship definition explains what action is being taken and possibly why it is important. It may be important to state who or what does the action, but it is not important to explain how the action is taken.

TRUE

An entity has its own identity that distinguishes it from each other entity.

TRUE

An identifier is a candidate key that has been selected to be used as the unique characteristic for an entity type.

TRUE

Domain definitions typically specify some (or all) of the following characteristics of attributes: data type, length, format, range, allowable values, meaning, uniqueness, and null support (whether an attribute value may or may not be null).

TRUE

Event entity types should be named for the result of the event, not the activity or process of the event.

TRUE

One situation in which a relationship must be turned into an associative entity is when the associative entity has other relationships with entities besides the relationship that caused its creation.

TRUE

The minimum cardinality of a relationship is the minimum number of instances of entity B that may be associated with each instance of entity A.

TRUE

The other deliverable from conceptual data modeling is a full set of entries about data objects that will be stored in the project dictionary, repository, or data modeling software.

TRUE

The process of conceptual data modeling begins with developing a conceptual data model for the system being replaced, if a system already exists. This is essential for planning the conversion of the current files or database into the database of the new system.

TRUE