SQL Review Quiz

Which clause can specify rows for aggregate functions?

• INSERT clause

• WHERE clause

• SELECT clause

• DELETE clause

What do aggregate queries construct from a table?

• New tables

• New cells

• New columns

• New rows

Which aggregate function is used to find the maximum value in a column?

• AVG(value)

• MIN(value)

• MAX(value)

• SUM(value)

What SQL keyword is used to provide more meaningful names to result sets?

• ALIAS

• TITLE

• AS

• NAME

Why might you use an ALIAS in a SQL query?

• To provide more meaningful names

• To make the query run faster

• To delete duplicate data

• To change the data type

What is the primary use of the GROUP BY clause in SQL?

• To sort records

• To group records with the same values

• To delete records

• To filter records

What is the purpose of using aliases in SQL queries?

• To rename columns or results

• To rename tables

• To join tables

• To delete data

What does the following SQL query do: SELECT MIN(dateOrdered) FROM orders?

• Counts the number of dates in the dateOrdered column

• Finds the latest date in the dateOrdered column

• Finds the earliest date in the dateOrdered column

• Sums up all the dates in the dateOrdered column

What does the AVG function do in SQL?

• Calculates the sum of values

• Finds the maximum value

• Finds the minimum value

• Calculates the average of values

Which of the following SQL statements correctly uses the COUNT function to count all rows in a table called employees?

• SELECT COUNT(NULL) FROM employees;

• SELECT COUNT(DISTINCT employee_id) FROM employees;

• SELECT COUNT(*) FROM employees;

• SELECT COUNT(employee_id) FROM employees;