4620 true and false
A disadvantage of the relational database management system (RDBMS) is its inability to hide the complexities of the relational model from the user.
False
Character data can contain any character or symbol intended for mathematical manipulation.
False
Composite attributes make it easier to facilitate detailed queries
False
Field refers to a collection of related records.
False
One disadvantage of the DBMS is that it increases the risk of data security breaches.
False
Software vendors have adopted the Chen representation because of its compact representation.
False
The one-to-many (1:M) relationship is easily implemented in the relational model by putting the foreign key of the "1" side in the table of the "many" side as a primary key.
False
A table is in fourth normal form if it is in third normal form and has no independent multivalued dependencies.
True
A weak entity has a primary key that is partially or totally derived from the parent entity in the relationship.
True
All relational tables satisfy the 1NF requirements.
True
Connectivities and cardinalities are established by concise statements known as business rules.
True
Data constitute the building blocks of information. 1
True
In an SQL-based relational database, rows in different tables are related based on common values in common attributes.
True
In the context of partial dependencies, data redundancies occur because every row entry requires duplication of data.
True
In the entity relationship model, a table row corresponds to an entity instance.
True
In the original Chen notation, each attribute is represented by an oval with the attribute name connected to an entity rectangle with a line.
True
It is possible for a table in 2NF to exhibit transitive dependency, where the primary key may rely on one or more nonprime attributes to functionally determine other nonprime attributes.
True
M:N relationships are not appropriate in a relational model.
True
One important inheritance characteristic is that all entity subtypes inherit their primary key attribute from their supertype.
True
RDBMSs enforce integrity rules automatically.
True
Since a partial dependency can exist only if a table's primary key is composed of several attributes, if a table in 1NF has a single-attribute primary key, then the table is automatically in 2NF.
True
The Crow's Foot notation is less implementation-oriented than the Chen notation.
True
The entity relationship model (ERM) is dependent on the database type.
True
The only way to access the data in a database is through the DBMS.
True
The practical significance of taking the logical view of a database is that it serves as a reminder of the simple file concept of data storage.
True
You can think of a table as a persistent representation of a logical relation.
True
An advantage of database systems is that you needn't perform frequent updates and apply latest patches.
False
An implementation-ready data model needn't necessarily contain enforceable rules to guarantee the integrity of the data.
False
An operational database is sometimes referred to as an enterprise database.
False
Business rules apply to businesses and government groups, but not to other types of organizations such as religious groups or research laboratories.
False
Corporations use only structured data.
False
Data and information are essentially the same thing.
False
Data anomaly is defined as the condition in which all of the data in the database are consistent with the real-world events and conditions
False
Data anomaly is defined as the condition in which all of the data in the database are consistent with the real-world events and conditions.
False
Data is the result of processing raw facts to reveal its meaning.
False
Database designers determine the data and information that yield the required understanding of the entire business.
False
Database programming languages receive all application requests and translate them into the complex operations required to fulfill those requests.
False
Even when a good database blueprint is available, an applications programmer's view of the data should match that of the manager and the end user.
False
In Chen notation, entities and relationships have to be oriented horizontally; not vertically.
False
In a natural join, the column on which the join was made occurs twice in the new table.
False
In an SQL-based relational database, each table is dependent on every other table
False
One advantage of a database system over previous data management approaches is that the database system is considerably less complex.
False
Only a single attribute, not multiple attributes, can define functional dependence.
False
Structural dependence exists when it is possible to make changes in the file structure without affecting the application program's ability to access the data.
False
The Crow's Foot notation easily identifies multivalued attributes.
False
The DBMS reveals much of the database's internal complexity to the application programs and users.
False
The SELECT operator yields a vertical subset of a table.
False
The external model is the representation of the database as "seen" by the DBMS.
False
The hierarchical model is software-independent.
False
The idea of determination is unique to the database environment.
False
The relational model is hardware-dependent and software-independent.
False
The row's range of permissible values is known as its domain.
False
When data are entered into a form and saved, they are placed in the underlying database as knowledge.
False
A composite identifier is a primary key composed of more than one attribute.
True
A data dictionary is sometimes described as "the database designer's database" because it records the design decisions about tables and their structures.
True
A data model is usually graphical.term-42
True
A data warehouse can store data derived from many sources. 1
True
A design trap occurs when a relationship is improperly or incompletely identified and is therefore represented in a way that is not consistent with the real world.
True
A null is created when you press the Enter key or the Tab key to move to the next entry without making a prior entry of any kind.
True
An entity cluster is a "virtual" entity type used to represent multiple entities and relationships in the ERD.
True
An entity in the entity relationship model corresponds to a table in the relational environment.
True
An entity supertype can have disjoint or overlapping entity subtypes.
True
An implementation-ready data model should contain a description of the data structure that will store the end-user data.
True
As rare as 1:1 relationships should be, certain conditions absolutely require their use.
True
At the implementation level, the supertype and its subtype(s) depicted in the specialization hierarchy maintain a 1:1 relationship.
True
Business rules must be rendered in writing
True
Data processing can be as simple as organizing data to reveal patterns. 1
True
Denormalization produces a lower normal form.
True
Dependency diagrams are very helpful in getting a bird's-eye view of all the relationships among a table's attributes.
True
Depending on the sophistication of the application development software, nulls can create problems when functions such as COUNT, AVERAGE, and SUM are used.
True
Each row in the relational table is known as an entity instance or entity occurrence in the ER model.
True
Each table in a relational database must have a primary key.
True
Entity supertypes and subtypes are organized in a specialization hierarchy.
True
If the attribute (B) is functionally dependent on a composite key (A) but not on any subset of that composite key, the attribute (B) is fully functionally dependent on (A).
True
Implementing overlapping subtypes requires the use of one discriminator attribute for each subtype.
True
In a 1:M relationship, to avoid the possibility of referential integrity errors, the data of the "1" side must be loaded first.
True
In order to meet performance requirements, portions of the database design may need to be occasionally denormalized.
True
In the Chen and Crow's Foot notations, an entity is represented with a rectangle containing the entity's name.
True
In the context of data models, an entity is a person, place, thing, or event about which data will be collected and stored.
True
Metadata describe the data characteristics and the set of relationships that links the data found within the database.
True
Normalization represents a micro view of the entities within the ERD.
True
Normalization works through a series of stages called normal forms.
True
One disadvantage of a database system over previous data management approaches is increased costs.
True
Relational algebra defines the theoretical way of manipulating table contents using relational operators.
True
Relational models view data as part of a table or collection of tables in which all key values must be identified.
True
Repeating groups must be eliminated by ensuring that each row defines a single entity.
True
Specialization is the top-down process of identifying lower-level, more specific entity subtypes from a higher-level entity supertype
True
Structure is based on the type of processing to be performed on the data.
True
The DIFFERENCE operator subtracts one table from the other.
True
The DIVIDE operation uses one single-column table (e.g., column "a") as the divisor and one two-column table (e.g., columns "a" and "b") as the dividend.
True
The combination of normalization and ER modeling yields a useful ERD, whose entities can be translated into appropriate table structures.
True
The completeness constraint can be partial or total.
True
The entity supertype contains common characteristics, and the entity subtypes each contain their own unique characteristics.
True
The network model has structural level dependence.
True
The objective of normalization is to ensure that each table conforms to the concept of well-formed relations.
True
The relationships depicted within the specialization hierarchy are sometimes described in terms of "is-a" relationships.
True
To implement a small database, a database designer must know the "1" and the "M" sides of each relationship and whether the relationships are mandatory or optional.
True
Today, most relational database products can be classified as object/relational.
True
Within the database environment, a data model represents data structures with the purpose of supporting a specific problem domain.
True
