SQL Order Group Distinct Aggregate Nested Having

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

• To delete data from a table

• To sort the result set of a query based on specified column(s) in ascending or descending order.

• To create a new table

• To update multiple records simultaneously

How does the GROUP BY clause work in SQL?

• The GROUP BY clause in SQL is used to filter rows based on a condition

• The GROUP BY clause in SQL is used to sort rows in ascending order

• The GROUP BY clause in SQL is used to update multiple rows simultaneously

• The GROUP BY clause in SQL is used to group rows that have the same values into summary rows.

Explain the usage of the DISTINCT keyword in SQL.

• The DISTINCT keyword in SQL is used to filter rows based on a specific condition.

• The DISTINCT keyword in SQL is used to sort the result set in ascending order.

• The DISTINCT keyword in SQL is used to eliminate duplicate rows from the result set.

• The DISTINCT keyword in SQL is used to perform mathematical operations on the result set.

What are some common aggregate functions in SQL?

• COUNT, SUM, AVG, MIN, MAX

• AVERAGE

• BIGGEST

• SMALLEST

• TOTAL

How can nested queries be used in SQL?

• Nested queries can be used in SQL by using only one query at a time

• Nested queries can be used in SQL by placing one query inside a comment

• Nested queries can be used in SQL by placing one query inside another query, typically within the WHERE clause or as a subquery in the SELECT statement.

• Nested queries can be used in SQL by placing one query inside a table name

When is the HAVING clause used in SQL?

• The HAVING clause is used to sort data in SQL

• The HAVING clause is used in SQL to filter the results of a GROUP BY clause based on specified conditions.

• The HAVING clause is used to update records in SQL

• The HAVING clause is used to join tables in SQL

What is the syntax for using the ORDER BY clause in SQL?

• ORDER column_name BY [ASC|DESC]

• ORDER column_name ASC|DESC

• ORDER BY column_name [ASC|DESC]

• ORDER BY column_name ASC|DESC

Give an example of a query using the GROUP BY clause in SQL.

• SELECT name, SUM(sales) FROM products GROUP BY category;

• SELECT department, COUNT(*) FROM employees GROUP BY department;

• SELECT city, COUNT(*) FROM customers GROUP BY country;

• SELECT AVG(age) FROM students GROUP BY grade;

How does the DISTINCT keyword eliminate duplicate values in SQL?

• The DISTINCT keyword eliminates duplicate values by only selecting unique rows from the result set.

• The DISTINCT keyword sorts the values alphabetically

• The DISTINCT keyword filters out NULL values

• The DISTINCT keyword groups similar values together

Name three aggregate functions commonly used in SQL.

• MIN

• COUNT, SUM, AVG

• TOTAL

• AVERAGE