EXAM LATEST 2024 ACTUAL 150 QUESTIONS WITH
DETAILED ANSWERS /A+ GRADE ASSURED
In a relational model, _______
are also used to establish relationships among tables and to ensure the integrity of
the data. - ANSWER: keys
A _____ key can be described as a minimal superkey, a superkey without any
unnecessary attributes. - ANSWER: candidate
A _____ key is defined as a key that is used strictly for data retrieval purposes. -
ANSWER: secondary
_____ logic, used extensively in mathematics, provides a framework in which an
assertion (statement of fact) can be verified as either true or false. - ANSWER:
Predicate
_____, also known as RESTRICT, yields values for all rows found in a table that satisfy
a given condition. - ANSWER: Select
Product yields all possible pairs of rows from two tables, also known as the
_________
product. - ANSWER: Cartesian
Proper use of ________ keys is crucial to controlling data redundancy - ANSWER:
foreign
A primary key is a(n) ______________
key chosen to be the primary means by which rows of a table are uniquely
identified. - ANSWER: candidate
A _____ is the primary key of one table that has been placed into another table to
create a common attribute. - ANSWER: foreign key
The relational operators have the property of ___________
; that is, the use of relational algebra operators on existing relations (tables)
produces new relations. - ANSWER: closure
In a database context, a(n) _____ indicates the use of different names to describe
the same attribute. - ANSWER: synonym
_____ relationships cannot be implemented as such in the relational model. -
ANSWER: M:N
, A(n) _____________________ provides a detailed description of all tables found
within the user/designer-created database. - ANSWER: data dictionary
To be considered minimally relational, the DBMS must support the key relational
operators _____, PROJECT, and JOIN. - ANSWER: Select
A(n) _____ only returns matched records from the tables that are being joined. -
ANSWER: inner join
An index key can have multiple _________________
(a composite index). - ANSWER: attributes
In the relational model, _____ are important because they are used to ensure that
each row in a table is uniquely identifiable. - ANSWER: keys
In a relational table, each column has a specific range of values known as the
_____________
domain. - ANSWER: attribute
The _____ relationship is the "relational model ideal." - ANSWER: 1:M
According to Codd's _____ rule of relational database, "Application programs and ad
hoc facilities are logically unaffected when changes are made to the table structures
that preserve the original table values (changing order of columns or inserting
columns)." - ANSWER: logical data independence
The order of the rows and columns is important to the DBMS. (T/F) - ANSWER: False
A(n) ____________
links tables on the basis of an equality condition that compares specified columns of
each table. - ANSWER: equijoin
When two or more tables share the same number of columns, and when their
corresponding columns share the same or compatible domains, they are said to be
_____ . - ANSWER: Union-Compatible
A table is also called a(n) _____________
because the relational model's creator, E. F. Codd, used the two terms as synonyms.
- ANSWER: relation
The __________
catalog can be described as a detailed system data dictionary that describes all
objects within the database, including data about table names, the table's creator
and creation date, the number of columns in each table, the data type corresponding
to each column, index filenames, index creators, authorized users, and access
privileges. - ANSWER: system