Database Processing-Chapter 4
(T or F) 7) When examining data values as a part of assessing table structure, you should try to determine functional dependencies.
TRUE Diff: 1 Page Ref: 128-129 Fig 4-1
(T or F) 8) When examining data values as a part of assessing table structure, you should try to determine multivalued dependencies.
TRUE Diff: 1 Page Ref: 128-129 Fig 4-1
(T or F) 9) When examining data values as a part of assessing table structure, you should try to determine the table's primary key.
TRUE Diff: 1 Page Ref: 128-129 Fig 4-1
(T or F) 18) Multivalued dependencies create anomalies so serious that multivalued dependencies must always be eliminated.
TRUE Diff: 1 Page Ref: 132
(T or F) 20) Creating a read-only database is a job often given to beginning database professionals.
TRUE Diff: 1 Page Ref: 132
(T or F) 24) Denormalization is the process of joining previously normalized tables back together.
TRUE Diff: 1 Page Ref: 132
(T or F) 27) Multivalued dependencies show up under a different name as the multivalued, multicolumn problem.
TRUE Diff: 1 Page Ref: 135-136
(T or F) 29) Null values are a problem because they are ambiguous.
TRUE Diff: 1 Page Ref: 137
(T or F) 12) The third step in assessing table structure is to check the validity of presumed referential integrity constraints.
TRUE Diff: 2 Page Ref: 128-1129 Fig 4-1
(T or F) 2) The first step in assessing table structure is to count rows and examine columns.
TRUE Diff: 2 Page Ref: 128-129 Fig 4-1
(T or F) 6) The second step in assessing table structure is to examine data values and determine dependencies and keys.
TRUE Diff: 2 Page Ref: 128-129 Fig 4-1
(T or F) 13) Database design varies depending on whether you're building an updateable database or a read-only database.
TRUE Diff: 2 Page Ref: 129
(T or F) 15) The presence of one or more foreign keys in a relation means that we cannot eliminate duplicated data in that table.
TRUE Diff: 2 Page Ref: 129
(T or F) 16) Normalization requires applications to use more complex SQL since they will need to write subqueries and joins to recombine data stored in separate relations.
TRUE Diff: 2 Page Ref: 129 Fig 4-2
(T or F) 25) Denormalization reduces the complexity of the SQL statements needed in an application to read required data.
TRUE Diff: 2 Page Ref: 133
84) Denormalization is simplejoin the data together and store it in a(n) ________.
table (or relation) Diff: 1 Page Ref: 132-133
31) When you are given a set of tables and asked to create a database to store their data, the first step is to ________. A) assess the existing tables' structure and content B) design the database structure C) create one or more new tables D) move the data into the new database E) design the applications that will use the database
A Diff: 1 Page Ref: 128-129 Fig 4-1
52) A table designed to store PhoneNumber01, PhoneNumber02 and PhoneNumber03 contains ________. A) the multivalued, multicolumn problem B) the inconsistent values problem C) the missing values problem D) the general-purpose remarks column problem E) None of the above is correct.
A Diff: 1 Page Ref: 135
46) A classic example of unneeded normalization is when we are dealing with ________. A) ZIP codes B) sales orders and line items C) association patterns D) multivalued dependencies E) general purpose remarks columns
A Diff: 2 Page Ref: 131
53) A form of multivalued dependency is found in ________. A) the multivalued, multicolumn problem B) the inconsistent values problem C) the missing values problem D) the general-purpose remarks column problem E) None of the above is correct.
A Diff: 2 Page Ref: 136
41) The advantages of normalization include ________. A) the elimination of modification anomalies B) the elimination of duplicated data C) more complex SQL for multitable subqueries and joins D) A and B E) A, B and C
A Diff: 3 Page Ref: 129 Fig 4-2
37) The SQL function COUNT ________. A) counts the number of columns in a table B) counts the number of rows in a table C) counts the number of tables in a database D) A and C E) B and C
B Diff: 1 Page Ref: 128
39) The SQL keyword TOP ________. A) limits the number of columns retrieved from a table B) limits the number of rows retrieved from a table C) limits the number of tables retrieved from a database D) A and C E) B and C
B Diff: 1 Page Ref: 128
49) For a number of reasons, ________ is not often an advantage for a read-only database. A) updating B) normalization C) denormalization D) A and B E) B and C
B Diff: 1 Page Ref: 132
55) You are creating a PRODUCT table using existing data from multiple sources. Examining the data, you find that you have "large red hat", "large hat, red", "red hat large" and "hat, large, red." This is an example of ________. A) the multivalue, multicolumn problem B) the inconsistent values problem C) the missing values problem D) the general-purpose remarks column problem E) None of the above is correct.
B Diff: 1 Page Ref: 136-137
57) A missing value is called a(n) ________. A) empty value B) null value C) missing value D) Any of A, B or C can be used. E) None of the above is correct.
B Diff: 1 Page Ref: 137-138
38) To limit the number of rows retrieved from a table, use the SQL construct ________. A) SELECT * B) SELECT TOP n * C) SELECT COUNT(TOP n) D) SELECT COUNT(*) E) SELECT COUNT *
B Diff: 2 Page Ref: 128
54) When a table is created using existing data from multiple sources, you are likely to find that the different sources code data in slightly different ways. This is an example of ________. A) the multivalued, multicolumn problem B) the inconsistent values problem C) the missing values problem D) the general-purpose remarks column problem E) None of the above is correct.
B Diff: 2 Page Ref: 136-137
40) You have been given two tables, CUSTOMER and SALE. You want to check the referential integrity constraint: SALE.CustomerNumber must exist in CUSTOMER.CustomerNumber You run the following SQL query: SELECT CustomerNumber FROM SALE WHERE CustomerNumber NOT IN (SELECT CustomerNumber FROM SALE, CUSTOMER WHERE SALE.CustomerNumber = CUSTOMER.CustomerNumber); What is shown in the results of this query? A) All values of CustomerNumber that match the constraint. B) All values of CustomerNumber that violate the constraint. C) All values of CustomerNumber where SALE.CustomerNumber = CUSTOMER.CustomerNumber. D) A and C E) B and C
B Diff: 3 Page Ref: 128
43) The presence of one or more foreign keys in a relation prevents ________. A) the elimination of modification anomalies B) the elimination of duplicated data C) more complex SQL for multitable subqueries and joins D) A and B E) A, B and C
B Diff: 3 Page Ref: 129
73) A defining requirement for ________ is that every determinant must be a candidate key.
BCNF Diff: 2 Page Ref: 130
42) The disadvantages of normalization include ________. A) the elimination of modification anomalies B) the elimination of duplicated data C) more complex SQL for multitable subqueries and joins D) A and B E) A, B and C
C Diff: 1 Page Ref: 129 Fig 4-2
33) The second step in assessing table structure includes ________. A) counting rows B) examining columns C) examining data values D) A and B E) B and C
C Diff: 2 Page Ref: 128-129 Fig 4-1
50) ________ is the process of joining two or more tables and storing the result as a single table. A) Querying B) Normalization C) Denormalization D) A and B E) B and C
C Diff: 2 Page Ref: 132
56) When a table is created using existing data from multiple sources, you are likely to find that some data values have never been provided. This is an example of ________. A) the multivalued, multicolumn problem B) the inconsistent values problem C) the missing values problem D) the general-purpose remarks column problem E) None of the above is correct.
C Diff: 2 Page Ref: 137-138
59) To check for null values in a column in a table, use the SQL phrase ________. A) IS B) IS NOT C) IS NULL D) COUNT(IS NOT) E) COUNT(IS NULL)
C Diff: 2 Page Ref: 137-138
60) The SQL keyword IS NULL can be used to ________. A) count the number of columns in a table B) count the number of rows in a table C) count the number of null values in a column D) A and C E) B and C
C Diff: 2 Page Ref: 137-138
63) To count the number of rows in a table, use the SQL construct ________.
COUNT(*) Diff: 2 Page Ref: 128
32) The first step in assessing table structure includes ________. A) counting rows B) examining columns C) examining data values D) A and B E) B and C
D Diff: 2 Page Ref: 128-129 Fig 4-1
44) Anomalies caused by functional dependencies can be eliminated by putting tables into ________. A) 1NF B) 2NF C) 3NF D) BCNF E) 4NF
D Diff: 2 Page Ref: 129
45) The defining characteristic of BCNF is that a table is in BCNF if ________. A) all rows are unique B) all columns are consistent C) the primary key is a candidate key D) all determinants are candidate keys E) all candidate keys are determinants
D Diff: 2 Page Ref: 130
47) Unlike the anomalies from functional dependencies, the anomalies from ________ are so serious that they should always be eliminated. A) ZIP codes B) sales orders and line items C) association patterns D) multivalued dependencies E) general purpose remarks columns
D Diff: 2 Page Ref: 132
58) A null value can indicate which of the following conditions? A) The value is inappropriate. B) The value is appropriate but unknown. C) The value is appropriate and known, but not entered into the database. D) All of A, B or C are correct. E) None of the above is correct.
D Diff: 2 Page Ref: 137-138
36) To count the number of rows in a table, use the SQL construct ________. A) SELECT * B) SELECT TOP n * C) SELECT COUNT(TOP n) D) SELECT COUNT(*) E) SELECT COUNT *
D Diff: 3 Page Ref: 128
81) ________ is the process of joining previously normalized tables back together.
Denormalization Diff: 1 Page Ref: 132-133
82) ________ reduces the complexity of the SQL statements needed in an application to read required data.
Denormalization Diff: 2 Page Ref: 132-133
48) Read-only databases are used for ________. A) updating B) querying C) reporting D) A and B E) B and C
E Diff: 1 Page Ref: 132
34) During the second step of the assessing table structure, you are trying to determine ________. A) multivalued dependencies B) functional dependencies C) foreign keys D) A and B E) A, B and C
E Diff: 2 Page Ref: 128-12 Fig 4-1
35) During the second step of the assessing table structure, you are trying to determine ________. A) primary keys B) candidate keys C) foreign keys D) A and B E) A, B and C
E Diff: 2 Page Ref: 128-129 Fig 4-1
51) An advantage of denormalization is ________. A) faster updating B) faster querying C) less complex SQL in application code D) A and B E) B and C
E Diff: 3 Page Ref: 132-133
(T or F) 28) When you are creating a database from existing data, you will have only minor problems with inconsistent values.
FALSE Diff: 1 Page Ref: 111
(T or F) 4) To determine the number and type of columns in a table, use the SQL construct COUNT(*).
FALSE Diff: 1 Page Ref: 128
(T or F) 10) When examining data values as a part of assessing table structure, there is no need to try to determine candidate keys other than the table's primary key.
FALSE Diff: 1 Page Ref: 128-129 Fig 4-1
(T or F) 11) When examining data values as a part of assessing table structure, there is no need to try to determine foreign keys.
FALSE Diff: 1 Page Ref: 128-129 Fig 4-1
(T or F) 22) Design guidelines and priorities are the same whether you're working with an updateable database or a read-only database.
FALSE Diff: 1 Page Ref: 132
(T or F) 30) General-purpose remarks columns rarely contain important data.
FALSE Diff: 1 Page Ref: 138139
(T or F) 3) To count the number of rows in a table, use the SQL construct COUNT(ROWS).
FALSE Diff: 2 Page Ref: 128
(T or F) 17) The standard sales order/line item pattern is a classic example of unneeded normalization.
FALSE Diff: 2 Page Ref: 131
(T or F) 21) Read-only databases are often updated.
FALSE Diff: 2 Page Ref: 132
(T or F) 23) Normalization is an advantage for a read-only database.
FALSE Diff: 2 Page Ref: 132
(T or F) 26) Read-only databases seldom use more than one copy of a set of same data.
FALSE Diff: 2 Page Ref: 134
(T or F) 14) Normalization eliminates modification anomalies and data duplication.
FALSE Diff: 3 Page Ref: 129 Fig 4-2
(T or F) 19) To eliminate multivalued dependencies, normalize your tables so that they are all in BCNF.
FALSE Diff: 3 Page Ref: 132
(T or F) 5) To limit the number of rows retrieved from a table, use the SQL keyword TOP.
TRUE Diff: 1 Page Ref: 128
90) The SQL keyword ________ can be used to count the number of nulls in a column.
IS NULL Diff: 1 Page Ref: 137-138
70) ________ requires application programmers to write complex SQL since they will need to write subqueries and joins to recombine data stored in separate relations.
Normalization Diff: 2 Page Ref: 129 Fig 4-2
83) ________ often use several copies of a set of same data, where each copy is modified for a specific use.
Read-only databases Diff: 2 Page Ref: 134
64) To determine the number and type of columns in a table, use the SQL construct ________.
SELECT * Diff: 1 Page Ref: 128
65) To limit the number of rows retrieved from a table, use the SQL keyword ________.
TOP Diff: 1 Page Ref: 128
(T or F) 1) When you are given a set of tables and asked to create a database to store their data, the first step is to assess the tables' structure and content.
TRUE Diff: 1 Page Ref: 128
89) Null values are a problem because they are ________.
ambiguous Diff: 3 Page Ref: 137-138
75) A relation is in BCNF if every determinant is a(n) ________.
candidate key Diff: 2 Page Ref: 130
62) The first step in assessing table structure is to ________ and ________.
count rows; examine columns Diff: 2 Page Ref: 128-129 Fig 4-1
74) A relation is in BCNF if every ________ is a candidate key.
determinant Diff: 2 Page Ref: 130
69) The presence of one or more ________ in a relation means that we will not be able to eliminate all duplicated data in that table.
foreign keys Diff: 3 Page Ref: 129
72) Relations in BCNF have no modification anomalies in regard to ________.
functional dependencies Diff: 3 Page Ref: 129
66) When examining data values as a part of assessing table structure, you should try to determine two types of dependencies: ________ and ________.
functional dependencies; multivalued dependencies Diff: 2 Page Ref: 128-129 Fig 4-1
87) You are creating a BOAT table using existing data from multiple sources, and you find that you have "power boat blue", "boat, power, blue" and "blue power boat" as data values for the same column. This is an example of the ________ problem.
inconsistent values Diff: 1 Page Ref: 135-139
61) When you are given a set of tables and asked to create a database to store their data, the first step is to assess the tables' ________.
structure and content Diff: 1 Page Ref: 128-129 Fig 4-1
68) The elimination of ________ and the reduction of ________ are advantages of normalization.
modification anomalies; duplicated data Diff: 3 Page Ref: 129 Fig 4-2
76) Anomalies from ________ are so serious that these structures must be eliminated.
multivalued dependencies Diff: 2 Page Ref: 132
85) Multivalued dependencies show up under a different name as the ________ problem.
multivalued, multicolumn Diff: 1 Page Ref: 135-139
86) If you have a table with a set of columns named "Child01", "Child02" and "Child03", the table has the ________ problem.
multivalued, multicolumn Diff: 1 Page Ref: 135-139
79) Read-only databases are ________ updated.
never Diff: 2 Page Ref: 132
88) A missing value is called a(n) ________.
null value Diff: 1 Page Ref: 137-138
71) Relations are sometimes left unnormalized to improve ________.
performance Diff: 3 Page Ref: 129
67) When examining data values as a part of assessing table structure, you should try to determine three types of keys: the ________, any additional ________ and any ________.
primary key; candidate keys; foreign keys Diff: 2 Page Ref: 128-129 Fig 4-1
78) Creating a ________ database is a job often given to beginning database professionals.
read-only Diff: 1 Page Ref: 132
80) Normalization is seldom an advantage for a ________ database.
read-only Diff: 2 Page Ref: 132
77) Writing SQL subqueries and joins against normalized tables is ________ compared to the code that must be written to handle anomalies from multivalued dependencies.
simple (or a similar word) Diff: 2 Page Ref: 132