Online Coding Lessons SQL and Database Basics 2

Question 1

Which SQL keyword removes duplicate rows from a SELECT result?

Accepted Answer

DISTINCT

Answer

UNIQUE

Answer

NODUPE

Answer

FILTER

Question 2

What SQL clause is used to combine rows from two or more tables based on a related column?

Accepted Answer

JOIN

Answer

MERGE

Answer

COMBINE

Answer

LINK

Question 3

Which SQL aggregate function returns the total number of rows in a result set?

Accepted Answer

COUNT()

Answer

SUM()

Answer

TOTAL()

Answer

SIZE()

Question 4

What does the UPDATE command do in SQL?

Accepted Answer

Changes existing data in one or more rows

Answer

Adds a new column to a table

Answer

Creates a brand new table

Answer

Refreshes the database connection

Question 5

In SQL, what does the wildcard character % represent when used with the LIKE operator?

Accepted Answer

Any sequence of zero or more characters

Answer

Exactly one character

Answer

Any single digit

Answer

A literal percent sign only

Question 6

Which SQL command is used to create a new database table?

Accepted Answer

CREATE TABLE

Answer

BUILD TABLE

Answer

MAKE TABLE

Answer

NEW TABLE

Question 7

What is the purpose of the GROUP BY clause in SQL?

Accepted Answer

Groups rows sharing the same value for use with aggregate functions

Answer

Sorts rows from largest to smallest

Answer

Joins two tables on a common column

Answer

Removes rows that have NULL values