CPP Database Programming & SQL

Question 1

Which SQL JOIN returns all rows from the left table and matching rows from the right table, with NULLs for non-matching right rows?

Accepted Answer

LEFT OUTER JOIN

Answer

INNER JOIN

Answer

RIGHT OUTER JOIN

Answer

FULL OUTER JOIN

Question 2

Which property of the ACID model ensures that a transaction either fully completes or has no effect on the database?

Accepted Answer

Atomicity

Answer

Consistency

Answer

Isolation

Answer

Durability

Question 3

A table is in Third Normal Form (3NF) if it is in 2NF and contains no:

Accepted Answer

Transitive dependencies

Answer

Repeating groups

Answer

Partial dependencies

Answer

Multi-valued attributes

Question 4

Which SQL clause is used to filter results after an aggregate function has been applied?

Accepted Answer

HAVING

Answer

WHERE

Answer

GROUP BY

Answer

ORDER BY

Question 5

What type of database index stores the data rows themselves in the index key order?

Accepted Answer

Clustered index

Answer

Composite index

Answer

Non-clustered index

Answer

Covering index

Question 6

In SQL, which command is used to permanently save a transaction's changes to the database?

Accepted Answer

COMMIT

Answer

SAVE

Answer

ROLLBACK

Answer

FLUSH

Question 7

Which of the following best describes a foreign key in a relational database?

Accepted Answer

A column that references the primary key of another table

Answer

A key that uniquely identifies every row in its own table

Answer

An index used to speed up foreign-table lookups

Answer

A composite key made of two or more columns