AN 324 Exam 1

Foreign Keys must be composite keys (T/F)

Foreign Keys must be composite keys (T/F)

False

Consider a relational database used by hospital to manage patients and primary care physicians. What is the likely cardinality of the relationship between patients and PCP?

1 to many
many to many
1 to 1

1 to many

A ________ is a big data store that can house data from multiple sources in its original format

Data Lake

_________ data is easily stored in a relational database management system.

Structured

which of the following is not part of the data deluge (big data)?

volume
variance
variety
velocity

Variance

the SELECT statement is an example of which of following?

Data definition language
data manipulation language
data control language
data dictionary language

Data manipulation language

which sql clause filters the results based on the group meeting a certain condition?

where
limit
having
order by

having

SQL SELECT clauses are written in a specific order, but the database processes the clauses in a different order. What is the first clause processed in a SELECT query?

FROM

What SQL key word is similar to an IF function in Excel or IF, THEN, ELSE in other coding languages?

Case

Which logical operator checks for patterns in a string?

IN
HAVING
LIKE
BETWEEN

LIKE

Which of these is NOT a mathematical function available in MySQL?

Median
STD
AVG
MAX

Median

A _______ allows you to combine tables horizontally.

JOIN

which type of join creates every combination of values from the left table and the right table and should be used with caution?

CROSS JOIN

Which kind of SQL clause could result in some NULL fields if there is not an exact match between the two tables being combined?

LEFT JOIN

JOINS always require linking primary keys and foreign keys between tables. (T/F)

False

Which of the following are required for a UNION query to work?

must include the same columns in both queries being combined

columns must have the same data type in both queries being combined

must include table or query alias

must include an ON clause

must include the same columns in both queries being combined

columns must have the same data type in both queries being combined

A subquery in the WHERE clause acts like a derived table. (T/F)

False

Parentheses are required around the inner query. (t/f)

true

in a _________ subquery, the inner query depends on the information from the outer query.

CORRELATED

Joins and subqueries can never be used interchangeably to answer questions. (t/f)

false

Subqueries can display data from the inner most query. (t/f)

False

a ______ acts like a virtual table that stores SQL statements so that you can run it on-demand.

VIEW

Which of the following is an example of Data Definition Language?

CREATE

Which of the following should be avoided when possible?

left joins, due to potential unexpected results

natural joins, due to potential unexpected results

correlated subqueries, due to efficiency

unions, due to efficiency

natural joins

correlated subqueries

which of the following keywords is used to delete objects, such as tables, from a database?

DROP