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Database Programming – Exam 2 Concept Review
Section 5 Lesson 4 to Section 9 Lesson 1
1.
Group functions return a value for (each row / a row set)
and (include / ignore) null values in their computations. They
can avoid computations involving duplicate values by including
the key word ________________ as an argument.
2.
Which group functions below act on text, number and
date data types?
a. SUM
b. MAX
c. MIN
d. AVG
e. COUNT
3.
If a select list contains both a column as well as a group
function then what clause is required?
a. having clause
b. join clause
c. order by clause
d. group by clause
4.
(True / False) Both the order by and group by clauses
can contain columns not found in the select list of their query.
5.
Indicate why the query below will not execute
successfully. (There may be more than one reason). Format
the code according to conventions so it will execute.
6.
Indicate why the following query will not execute
successfully. (There may be more than one reason.) Format
the code according to conventions so it will execute.
Select job_id, avg(salary) from employees where avg(salary) >
(select avg(salary) from employees group by department_id)
group by job_id;
7.
In using the INSERT statement, if a column list is not
provided then what values must be included?
a.
a value for any column defined as not null.
b.
a value for any column that does not have an
explicit default value.
c.
a value for every column in the table in the correct
order.
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Database Programming – Exam 2 Concept Review
Section 5 Lesson 4 to Section 9 Lesson 1
d.
key.
only values for column(s) that make up the primary
8.
(True / False ) Multiple subqueries may be used in
SELECT, INSERT and UPDATE statements, but not DELETE
statements.
9.
You wish to change an existing department_id to a new
department_id that does not exist. You also want to delete the
old department id. There is a foreign key for department_id on
your employees table that references the primary key in the
departments table. What DML operations are needed?
a.
An insert to departments, an update on
employees, a delete on departments
b.
An insert to employees, an update on
departments, a delete on employees.
c.
An update to the departments table followed by a
merge to the employees table.
d.
an update to the departments table and an update
to the employees table.
10.
When the WHERE clause is missing in a delete
statement then: (choose all true answers)
a.
all rows will be deleted from the table.
b.
the table will be removed from the database.
c.
rows can be restored using the RESTORE
command
d.
an error message will be displayed indicating
incorrect syntax.
11.
Implicit defaults will be used in the INSERT clause for
columns not found in the __ list. To assign a default value
explicitly for columns in the values clause, you must use the key
word __________.
12.
Which keywords are used in DML statements?
a.
create, alter, drop
b.
insert, update, delete
c.
select, from, where
d.
rename, truncate, delete
13.
A transaction can be defined as:
a.
a SELECT statement ordering rows
b.
a set of data control commands
c.
collection of DML statements that form a logical
unit of work.
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Database Programming – Exam 2 Concept Review
Section 5 Lesson 4 to Section 9 Lesson 1
d.
14.
any set of SQL statements
To add a row to a table, you use the
a.
insert statement
b.
add row statement
c.
alter row statement
d.
modify column statement
15.
When adding a row to a table, you must specify 3 things
in the insert statement:
a.
datatype, table name, alias
b.
row number, column name, table primary key
c.
table name, column name and values
d.
input table, primary key, alias
16. Which of the following would be found in an explicit insert
statement.
a. no column list is present
b. no values list is present
c. NULL keyword appears in the values list
d. NULL is not allowed in an explicit insert statement
17.To insert the current date and time, use:
a.
TO_DATE
b.
TO_CHAR
c.
CURRENT_DATE
d.
SYSDATE
18. You can insert rows from one table to another using:
a. UPDATE
b. INSERT row
c. modify table
d. subquery
19. If you omit the WHERE clause in an UPDATE statement:
a.
no rows are changed
b.
all rows are changed
c.
the query will not execute
d.
an error message will appear
20. If you include a group function in a SELECT clause, which
of the following is true?
a.
the function will only return one row
b.
you must include all non group function columns in
the SELECT clause in a GROUP BY clause
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Database Programming – Exam 2 Concept Review
Section 5 Lesson 4 to Section 9 Lesson 1
c.
d.
group functions are not put in the SELECT clause
the query will generate an error
21. Which of the following is true?
a. GROUP BY clauses can only list one column name
b. The column names in a GROUP BY clause must have
an alias
c. Group functions must be in the WHERE clause
d. The GROUP BY column does not have to be in the
SELECT list.
22. T/F HAVING clauses are used to restrict rows being
selected.
23. T/F A group function that finds the average will ignore NULL
values
24. To change a table, you must specify 4 things:
a. select clause, column alias, from clause
b. conditions, values, data types, table constraints
c. table name, row names, insert statement
d. table, columns, values, conditions.
25. Subqueries can be used in an update statement in 2 places:
a. set clause and where clause
b. from clause and the where clause
c. select clause and the from clause
d. update clause and the where clause
26. T/F To delete rows from an existing table, you must use the
DROP statement.
27. Which of the following are NOT data types?
a. SNOB
b. VAR2
c. VARCHARS
d. TIMESHARE
28. Which statement below is used to add, modify or drop
columns?
a. UPDATE
b. INSERT
c. DROP
d. ALTER
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Section 5 Lesson 4 to Section 9 Lesson 1
29. If you want to remove all rows from a table to release the
storage space
the best statement to use is:
a. UPDATE
b. DELETE
c. TRUNCATE
d. ELIMINATE
30. Which of the following will correctly add comments to a
table?
a. COMMENT ' This is my table'
b. INSERT COMMENT ' This is my table'
c. COMMENT ON TABLE mytable IS 'This is my table'
d. TABLE COMMENT IS ' This is my table'
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