Chapter 5
To correct anomalies in a database, tables must be converted into various types of normal forms. a. True b. False
True
What is a nonkey column? a. A column that is not part of the primary key. b. A column that has a null value. c. A column that is part of a repeating group. d. A column that contains a numeric value.
a. A column that is not part of the primary key.
If B is functionally dependent on A, what can you also say? a. A functionally determines B b. A functionally determines another attribute in the table c. B functionally determines A d. B does not determine any other attribute
a. A functionally determines B
Which of the following is a characteristic of a table that is in first normal form? a. It doesn't contain repeating groups. b. It has at least two foreign keys. c. It doesn't have a primary key d. There are no alternate keys.
a. It doesn't contain repeating groups.
Which of the following contains a repeating group where the primary key is OrderNum? a. Orders (OrderNum, OrderDate, (ItemNum, NumOrdered) ) b. Orders (OrderNum, OrderDate, ItemNum, NumOrdered ) c. Orders (OrderNum, OrderDate) d. Orders (OrderNum, ItemNum, NumOrdered )
a. Orders (OrderNum, OrderDate, (ItemNum, NumOrdered) )
Second normal form can be defined as a table that is in first normal form but that contains no ____. a. partial dependencies b. alternate keys c. nonkey columns d. interrelation constraints
a. partial dependencies
What do you call a data inconsistency that results from data redundancy or the use of inappropriate nulls? a. update anomaly b. insertion anomaly c. deletion anomaly d. relational anomaly
a. update anomaly
A(n) ________________ key is a candidate key not chosen ad the primary key.
alternate
If there is more than one possible choice for the primary key, and one of the possibilities is chosen to be the primary key. What are the others called? a. canceled keys b. alternate keys c. nonkey attributes d. contributory keys
b. alternate keys
What is each key that meets the criteria for a primary key called? a. alternate key b. candidate key c. functional key d. normal key
b. candidate key
Which of the following is a column or collection of columns on which all columns in the table are functionally dependent? a. index key b. candidate key c. major key d. special key
b. candidate key
If you convert a collection of tables to an equivalent third normal form collection of tables, what problems do you remove? a. those arising from multivalued dependencies b. those arising from functional dependencies c. those arising from inappropriate null values d. those arising from incomplete deletions
b. those arising from functional dependencies
What is a table that contains a repeating group called? a. normalized relation b. unnormalized relation c. nominal relation d. non-nominal relation
b. unnormalized relation
The normalization process is a series of steps that will automatically restructure your database to resolve design flaws. a. True b. False
b. false
What is the difference between a third normal form and fourth normal form table? a. A 4NF table has no alternate keys. b. A 4NF table has no foreign keys. c. A 4NF table has no multivalued dependencies. d. A 4NF table has no primary dependencies.
c. A 4NF table has no multivalued dependencies.
Which normal form has an additional condition that the only determinants the table contains are candidate keys? a. First b. Second c. Third d. Fourth
c. Third
What is an alternate key? a. foreign key b. primary key c. column that could be a primary key but was not chosen d. row that could be a primary key but was not chosen
c. column that could be a primary key but was not chosen
What type of diagram uses arrows to indicate all the functional dependencies present in a table? a. interrelation diagram b. functional diagram c. dependency diagram d. index diagram
c. dependency diagram
Which of the following can be defined as a column (or collection of columns) A such that all other columns are functionally dependent on A and no subcollection of the columns in A has this property? a. functional key b. composite key c. primary key d. declared key
c. primary key
Which term's definition also defines a candidate key? a. functional key b. repeating group c. primary key d. nonkey column
c. primary key
What is a potential problem, if any, if you design a database in which the last name of a consultant functionally determines the consultant's address? a. There is no problem with this design. b. There could be two consultants living at the same address. c. There could be more than one consultant with the same last name. d. The address will automatically functionally determine the consultant's last name.
c. There could be more than one consultant with the same last name.
An interrelation ____________________ is a condition that involves two or more relations.
constraint
With the table Orders (OrderNum, OrderDate, (ItemNum, NumOrdered) ) where OrderNum is the primary key, how would you convert the table to first normal form? a. by creating a second table with just the columns ItemNum and NumOrdered b. by changing the primary key to OrderDate c. by making ItemNum a foreign key d. by making the primary key a combination of OrderNum and ItemNum
d. by making the primary key a combination of OrderNum and ItemNum
When is a 1NF table automatically a 2NF table? a. when two or more columns make up the primary key b. when there are no interrelation constraints c. when there are only nonkey columns d. when the primary key contains only a single column
d. when the primary key contains only a single column
When you normalize a table by breaking down the relations into progressively finer levels of detail, it is called_____________________.
decomposition
A table that contains a ________________ that is not a candidate key indicates the table is not in third normal form.
determinant
Any column or collection of columns that determines another column is called a(n) ___________________.
determinant
A column is a nonkey column when it is part of the primary key. a. True b. False
false
Any row that determines another row is called a determinant. a. True b. False
false
Converting to third normal form always avoids the problems related to dependencies. a. True b. False
false
Functional dependencies can always be determined by looking at sample data. a. True b. False
false
If column B is functionally dependent on column A, you can also say that column B functionally determines column A. a. True b. False
false
If the primary key of a table contains only a single column, the table is automatically in third normal form. a. True b. False
false
When converting a non-first normal form table to first normal form, the foreign key will usually include the original foreign key concatenated with the key to the repeating group. a. True b. False
false
A column B is ____________________ on another column A if each value for A in the database is associated with exactly one value of B.
functionally dependent
A table is in fourth normal form when it is in third normal form and there are no ________________ dependencies.
multivalued
The ____________________ process enables you to identify the existence of potential problems in the design of a database.
normalization
A column is a nonkey column if it is not a part of the ____________________.
primary key
When the ____________________ of a table is a single column, the table is automatically in second normal form.
primary key
A table is in fourth normal form (4NF) when it is in third normal form and there are no multivalued dependencies. a. True b. False
true
A table that is in first normal form may contain problems that will require you to restructure it. a. True b. False
true
An interrelation constraint is a condition that involves two or more relations. a. True b. False
true
Tables that are in second normal form can still contain redundancy problems. a. True b. False
true
Tables without repeating groups are said to be in first normal form. a. True b. False
true
Third normal form is sometimes referred to as the Boyce-Codd normal form. a. True b. False
true