62) 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(*)
63) 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) counts the number of updates to a database
64) To limit the number of rows retrieved from a table, use ________.
A) SELECT *
B) SELECT TOP n *
C) SELECT COUNT(TOP n)
D) SELECT COUNT(*)
65) The TOP keyword ________.
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
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66) 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 CUSTOMER);
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) All values of Customer number that are in CUSTOMER but not in SALE.
67) 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) simpler SQL queries
68) 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) Both A and B are correct
69) Practical problems in designing databases from existing data include all of the following
except ____________.
A) The multivalue, multicolumn problem
B) functional dependencies
C) Inconsistent values
D) Missing values
70) Anomalies caused by functional dependencies can be eliminated by putting tables into
________.
A) 1NF
B) 2NF
C) 3NF
D) BCNF
71) 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
72) 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
73) Unlike the anomalies from functional dependencies, the anomalies from ________ are so
serious that they should always be eliminated.
A) general purpose remarks columns
B) sales orders and line items
C) association patterns
D) multivalued dependencies
74) Read-only databases are used for ________.
A) updating
B) querying
C) data entry
D) user account management
75) For a number of reasons, ________ is not often an advantage for a read-only database.
A) updating
B) normalization
C) denormalization
D) Both A and B are correct
76) ________ is the process of joining two or more tables and storing the result as a single table.
A) Querying
B) Normalization
C) Denormalization
D) Updating
77) An advantage of denormalization is ________.
A) faster updating
B) faster querying
C) faster copying of data
D) faster design
78) A table with columns PhoneNumber01, PhoneNumber02, and PhoneNumber03 is likely to
have ________.
A) the multivalue, multicolumn problem
B) the inconsistent values problem
C) the missing values problem
D) the general-purpose remarks column problem
79) 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
80) 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
81) 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 multivalued, multicolumn problem
B) the inconsistent values problem
C) the missing values problem
D) the general-purpose remarks column problem
82) The problem of misspelled data entries is really the same as ________.
A) the multivalue, multicolumn problem
B) the inconsistent values problem
C) the missing values problem
D) the general-purpose remarks column problem
83) When a table is created using existing data from multiple sources, you are likely to find that
some data values have never been provided because the values are not known. 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
84) When a table is created using existing data, you are likely to find that some data values have
never been provided because any value there would be inappropriate. 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
85) Reviewing the work done on a table that was created using existing data from multiple
sources, you are likely to find that some data values that were provided were never entered into
the table. 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
86) A missing value is called a(n) ________.
A) empty value
B) null value
C) missing value
D) deleted value
87) A null value can indicate which of the following conditions?
A) The value is incorrect.
B) The value is appropriate but unknown.
C) The value has been updated.
D) The value can never be changed.
88) To check for null values in a column in a table, use the ________ phrase.
A) IS
B) IS NOT
C) IS NULL
D) COUNT(NULL)
89) The keyword IS NULL can be used to help ________.
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) count the number of values in a column
90) Reviewing the work done on a table that was created using existing data from multiple
sources, you find that a column named Remarks has been included, and it is populated with
inconsistent and verbose verbal data. 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
91) Describe the steps in assessing table structure when you are given a set of tables and asked to
construct a new database to store the existing data.
92) When accessing table structure, how do you determine how many rows are in a table?
93) When assessing table structure, how do you determine the number and types of columns in a
table?
94) When accessing table structure, and determining the number and types of columns in a table,
how can you control how many rows are returned?
95) What are the advantages and disadvantages of normalization?
96) Explain denormalization, and why it may be appropriate to denormalize a set of tables.
97) What is the multivalue, multicolumn problem, and why is it a problem? Include an example.
98) What are inconsistent values, and why are they a problem?
99) What are null values, and why are they a problem?
100) What are general-purpose remarks columns, and why are they a problem?