Data and Analytics SQL and Database Fundamentals 3

Question 1

Which SQL command permanently removes a table and its data from the database?

Accepted Answer

DROP

Answer

DELETE

Answer

TRUNCATE

Answer

REMOVE

Question 2

What is the difference between UNION and UNION ALL in SQL?

Accepted Answer

UNION removes duplicates; UNION ALL keeps all rows

Answer

UNION allows NULL; UNION ALL does not

Answer

UNION sorts results; UNION ALL does not

Answer

UNION requires same column count; UNION ALL does not

Question 3

Which type of database is best suited for storing unstructured or semi-structured data?

Accepted Answer

NoSQL

Answer

Relational (RDBMS)

Answer

Hierarchical

Answer

Network

Question 4

What does ACID stand for in database transactions?

Accepted Answer

Atomicity, Consistency, Isolation, Durability

Answer

Accuracy, Completeness, Integrity, Dependency

Answer

Automation, Control, Integration, Distribution

Answer

Availability, Consistency, Isolation, Distribution

Question 5

What is a stored procedure in SQL?

Accepted Answer

A precompiled set of SQL statements stored in the database

Answer

A backup copy of a table

Answer

A type of database constraint

Answer

An automated query scheduler

Question 6

Which SQL clause specifies the condition for filtering rows in a SELECT statement?

Accepted Answer

WHERE

Answer

FROM

Answer

SELECT

Answer

GROUP BY