Database Storage & Design Appendix G 1 Answer Aacsb Information Technology Difficulty Easy Lo Define And Illustrate The Terms

Database Processing, 15e (Kroenke)

Appendix G: Physical Database Design and Data Structures for Database Processing

1) A flat file is a file that has repeating groups.

Answer: FALSE

2) The DBMS creates physical records, also called blocks, on its direct access fields.

Answer: TRUE

3) Each physical record is addressed by its sequential record number (SRN).

Answer: FALSE

4) Linked lists can be used to keep records in a logical order even if they are not necessarily in

physical order.

Answer: TRUE

5) In a linked list, the sequence field holds the address of the next record in the logical sequence.

Answer: FALSE

6) A two-way linked list has links in both directions.

Answer: TRUE

7) An index is a table that cross-references record addresses with some attribute value.

Answer: TRUE

8) A multilevel index that allows both sequential and direct processing of data records is called a

C-tree.

Answer: FALSE

9) A simple network is a collection of records and the 1:N relationships between them.

Answer: TRUE

10) A complex network is a collection of records and the 1:N relationships between them.

Answer: FALSE

11) A tree structure cannot be represented using indexes.

Answer: FALSE

12) To represent a tree structure using indexes, store each 1:N relationship as an index.

Answer: TRUE

13) A simple network can be represented using linked lists and indexes.

Answer: TRUE

14) A complex network cannot be decomposed into trees or simple networks.

Answer: FALSE

15) An intersection record is a record that is created when a complex network is decomposed

into a simple network.

Answer: TRUE

16) The word key indicates a field or fields whose value uniquely or nonuniquely identifies a

record or set of records.

Answer: TRUE

17) The primary work key is a field or fields whose value uniquely identifies a record.

Answer: FALSE

18) The term set refers to all records having the same nonunique secondary key.

Answer: TRUE

19) The performance of a database is normally measured by the time it takes to complete query

and update operations.

Answer: TRUE

20) The performance of a database is normally measured by the time it takes to update operations

and create a sequential list.

Answer: FALSE

21) Decomposition is the most important feature of physical database design.

Answer: FALSE

22) Indexes are the single most important tool for performance enhancement in a relational

database.

Answer: TRUE

23) With clustering, we can store records from two or more tables in the same file physically as

long as they are in the same entities logically.

Answer: FALSE

24) While clustering of records from two or more tables can enhance the performance of some

join queries, other queries may see diminished performance.

Answer: TRUE

25) A table may be decomposed in one of two ways, namely, horizontal decomposition and

sharding

Answer: FALSE

26) Aspects of physical database design that can be monitored and changed by the DBA include

all of the following except _________ .

A) indexes

B) clustering

C) flat files

D) decomposition

Answer: C

27) Regarding decomposition all of the following statements are true except for ______.

A) In a relational DBMS, when a table is decomposed we call the resulting subtables partitions

B) In vertical decomposition, every partition has the same number of rows

C) In horizontal decomposition, the rows of a table are split into multiple smaller tables, with

each row assigned to exactly on partition

D) Each vertical partition contains a copy of the foreign key of the original table

Answer: D

28) Select the correct statement below.

A) MySQL automatically creates an index on each primary key but not foreign keys.

B) The DBA needs to decide which rows to index.

C) SQL Server, Oracle Database, and MySQL all use a form of B-tree for most indexing.

D) Indexes are one of many tools for performance enhancement in a relational database.

Answer: C

29) A ________ is a file that has no repeating groups.

A) flat file

B) stacked file

C) record file

D) key file

Answer: A

30) The DBMS creates ________, also called blocks, on its direct access fields.

A) pseudo records

B) physical records

C) secondary file records

D) key file records

Answer: B

31) Each physical record is addressed by its ________.

A) relative record number (RRN)

B) sequential record number (SRN)

C) transaction record number (TRN)

D) ultimate record number (URN)

Answer: A

32) Linked lists can be used to keep records in ________.

A) logical order

B) physical order

C) sequential order

D) pseudo order

Answer: A

33) A collection of records and the 1:N relationships between them is a ________.

A) simple network

B) complex network

C) compound network

D) logical network

Answer: A

34) A collection of records and the N:M relationships between them is a ________.

A) simple network

B) complex network

C) compound network

D) logical network

Answer: B

35) DBMS products represent trees using all of the following except ________.

A) indexes

B) linked lists

C) sequential lists

D) secondary lists

Answer: D

36) Simple networks can be represented by using ________.

A) indexes or linked lists

B) linked lists or sequential lists

C) sequential lists or indexes

D) complex networks

Answer: A

37) Complex networks can be represented by reducing them to simple networks, and then

representing the simple networks using ________.

A) indexes or linked lists

B) linked lists or sequential lists

C) sequential lists or indexes

D) trees

Answer: A

38) Complex networks can be represented by reducing them to simple networks, which requires

the introduction of a(n) ________.

A) association record

B) link record

C) intersection record

D) sequential record

Answer: C

39) Keys may include all of the following except ________.

A) primary keys

B) unique secondary keys

C) nonunique secondary keys

D) nonunique primary keys

Answer: D

40) The term set refers to all records that have the same ________.

A) primary key

B) unique secondary key

C) nonunique secondary key

D) search key

Answer: C

41) Each of the following is an example of a data structure except ________.

A) binary relationship

B) sequential list

C) linked list

D) index

Answer: A

42) Data structures are typically used to ________.

A) unbalance a B-Tree

B) represent simple and complex networks

C) enhance database security

D) fry an egg

Answer: B

43) In a B-Tree whose top entry contains the values 47 and 88, the middle arrow allows access to

all records whose key field values are ________.

A) less than 47

B) greater than 47 and less than 88

C) greater than 47 and less than or equal to 88

D) greater than 88

Answer: C

44) An important property of B-Trees is that they are balanced to maintain efficient and

predictable performance. “Balanced” here means that ________.

A) every pointer allows access to the same number of data records

B) the numbers at every level of the B-Tree have the same average value

C) the key field values are the same at every level

D) every data record is the same distance from the top entry of the B-Tree

Answer: D

45) How does a DBMS store data on its direct access files?

Answer: Usually the DBMS creates large physical records, also called blocks. The physical

46) What is a linked list?

Answer: A linked list is a logical tool used to keep records in a logical order that may differ

47) What is a B-tree?

Answer: A B-tree is a multilevel index that allows both sequential and direct processing of data

48) What are tree, simple networks and complex networks?

Answer: A tree is a set of records and the 1:N relationships between them, where a child record

49) What is a set?

Answer: A key is a field that identifies a record. We can have primary keys, which uniquely

50) Explain how you can use clustering to store records in a database.

Answer: With clustering, also called co-clustering, we can store records from two or more tables