ORDER BY multiple columns in SQL - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to sort the results by the column 'age'.

SQL

SELECT * FROM employees ORDER BY [1];

Drag options to blanks, or click blank then click option'

Asalary

Bname

Cage

Ddepartment

Attempts:

3 left

💡 Hint

Common Mistakes

Using a column name not in the table.

Forgetting to specify the column after ORDER BY.

The ORDER BY clause sorts the results by the specified column. Here, sorting by age orders the employees by their age.

2fill in blank

medium

Complete the code to sort the results by 'department' first, then by 'salary'.

SQL

SELECT * FROM employees ORDER BY [1], salary;

Drag options to blanks, or click blank then click option'

Aage

Bposition

Cname

Ddepartment

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the order of columns in ORDER BY.

Using a column not in the table.

The ORDER BY clause can sort by multiple columns. Here, it sorts first by department, then by salary.

3fill in blank

hard

Fix the error in the code to correctly order by 'department' ascending and 'salary' descending.

SQL

SELECT * FROM employees ORDER BY department, salary [1];

Drag options to blanks, or click blank then click option'

AASC

BDESC

CDOWN

DUP

Attempts:

3 left

💡 Hint

Common Mistakes

Using invalid keywords like UP or DOWN.

Omitting ASC or DESC when needed.

By default, ORDER BY sorts the first column ('department') ascending. To sort the second column ('salary') descending, use DESC.

4fill in blank

hard

Fill both blanks to order by 'department' ascending and 'salary' descending.

SQL

SELECT * FROM employees ORDER BY department [1], salary [2];

Drag options to blanks, or click blank then click option'

AASC

BDESC

CUP

DDOWN

Attempts:

3 left

💡 Hint

Common Mistakes

Using invalid keywords like UP or DOWN.

Mixing the order of ASC and DESC.

Use ASC for ascending order and DESC for descending order in the ORDER BY clause.

5fill in blank

hard

Fill all three blanks to order by 'department' ascending, 'salary' descending, and 'age' ascending.

SQL

SELECT * FROM employees ORDER BY [1] [2], salary [3], age;

Drag options to blanks, or click blank then click option'

Adepartment

BDESC

CASC

Dage

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing column names and order keywords.

Using wrong order keywords like UP or DOWN.

The ORDER BY clause can sort by multiple columns with different directions. Here, 'department' ascending, 'salary' descending, and 'age' ascending.

Practice

1.

What does the SQL clause ORDER BY column1, column2 do?

easy

A. Filters rows where column1 equals column2

B. Sorts the results only by column2

C. Sorts the results first by column1, then by column2 if there are ties in column1

D. Groups rows by column1 and column2

Solution

1. Step 1: Understand ORDER BY with multiple columns

   The ORDER BY clause sorts rows by the first column listed.

2. Step 2: Sorting with tie-breaker column

   If two or more rows have the same value in the first column, sorting continues by the second column.

3. Final Answer:

   Sorts the results first by column1, then by column2 if there are ties in column1 -> Option C

4. Quick Check:

   ORDER BY multiple columns sorts stepwise [OK]

Hint: ORDER BY sorts by first column, then next for ties [OK]

Common Mistakes:

• Thinking ORDER BY filters rows
• Assuming it groups data
• Believing it sorts only by the last column

2.

Which of the following is the correct syntax to sort by age ascending and then by name descending?

SELECT * FROM users ORDER BY ...

easy

A. age ASC, name DESC

B. age DESC, name ASC

C. ORDER BY age DESC, name

D. age, name ASC

Solution

1. Step 1: Specify sorting order for each column

   Use ASC for ascending and DESC for descending explicitly after each column.

2. Step 2: Apply correct order for age and name

   Since age is ascending and name is descending, write age ASC, name DESC.

3. Final Answer:

   age ASC, name DESC -> Option A

4. Quick Check:

   Correct syntax uses ASC and DESC per column [OK]

Hint: Use ASC or DESC after each column in ORDER BY [OK]

Common Mistakes:

• Omitting ASC or DESC and expecting default
• Mixing order keywords incorrectly
• Using ORDER BY twice in one query

3.

Given the table products with columns category and price, what will this query return?

SELECT category, price FROM products ORDER BY category ASC, price DESC;

medium

A. Rows sorted by category alphabetically, then by price highest to lowest within each category

B. Rows sorted by price descending only

C. Rows sorted by category descending, then price ascending

D. Rows grouped by category and price

Solution

1. Step 1: Analyze ORDER BY clause

   The query orders rows first by category ascending (A to Z).

2. Step 2: Understand secondary sorting

   Within each category, rows are sorted by price descending (highest to lowest).

3. Final Answer:

   Rows sorted by category alphabetically, then by price highest to lowest within each category -> Option A

4. Quick Check:

   ORDER BY sorts stepwise by listed columns [OK]

Hint: First column sorts main order, second breaks ties [OK]

Common Mistakes:

• Confusing ascending and descending order
• Thinking ORDER BY groups rows
• Ignoring second column sorting

4.

Identify the error in this query:

SELECT * FROM employees ORDER BY salary DESC,;

medium

A. Missing ASC or DESC after salary

B. Extra comma after DESC causes syntax error

C. ORDER BY cannot have multiple columns

D. salary is not a valid column

Solution

1. Step 1: Check ORDER BY syntax

   The ORDER BY clause lists columns separated by commas without trailing commas.

2. Step 2: Identify trailing comma error

   The comma after DESC is extra and causes a syntax error.

3. Final Answer:

   Extra comma after DESC causes syntax error -> Option B

4. Quick Check:

   Trailing commas in ORDER BY cause syntax errors [OK]

Hint: No comma after last ORDER BY column [OK]

Common Mistakes:

• Leaving trailing commas in ORDER BY
• Forgetting ASC or DESC (defaults to ASC though)
• Assuming ORDER BY accepts invalid columns

5.

You have a students table with columns grade (integer) and last_name (text). You want to list students sorted by grade descending, but for students with the same grade, sort by last name ascending. Which query achieves this?

hard

A. SELECT * FROM students ORDER BY grade DESC last_name ASC;

B. SELECT * FROM students ORDER BY last_name ASC, grade DESC;

C. SELECT * FROM students ORDER BY grade ASC, last_name DESC;

D. SELECT * FROM students ORDER BY grade DESC, last_name ASC;

Solution

1. Step 1: Determine primary sorting column and order

   Primary sort is by grade descending (highest grade first).

2. Step 2: Determine secondary sorting column and order

   For ties in grade, sort by last_name ascending (A to Z).

3. Step 3: Write correct ORDER BY syntax

   Use ORDER BY grade DESC, last_name ASC with comma separating columns.

4. Final Answer:

   SELECT * FROM students ORDER BY grade DESC, last_name ASC; -> Option D

5. Quick Check:

   ORDER BY multiple columns with specified directions [OK]

Hint: List columns in ORDER BY with desired ASC/DESC per column [OK]

Common Mistakes:

• Swapping order of columns in ORDER BY
• Missing comma between columns
• Omitting ASC or DESC keywords