How to Use SQL ORDER BY DESC: Syntax, Examples & Traps

In relational databases, rows have no default order. Without an explicit ORDER BY clause, query engines return records in whatever order storage pages are read. To rank highest-paying salaries, surface recent orders, or sort names in reverse alphabetical order, use ORDER BY DESC.

1. Basic Syntax and Sorting Rules

SELECT employee_id, first_name, salary
FROM employees
ORDER BY salary DESC;

When you sort with DESC, different data types behave as follows:

According to the PostgreSQL Documentation on ORDER BY, sorting evaluates near the end of the SQL logical execution pipeline—right after SELECT—which allows you to sort by column aliases and computed fields.

2. Sample Dataset: employees

We will run the following examples against a sample employees table:

3. Core Examples

Example 1: Sort by a Single Column (Numbers & Dates)

To retrieve employees with the highest salary first:

SELECT name, salary
FROM employees
ORDER BY salary DESC;

Output:

To sort by newest hire date first, apply DESC to the date column:

SELECT name, hire_date
FROM employees
ORDER BY hire_date DESC;

Example 2: Sort by Multiple Columns (ASC + DESC)

When multiple rows share the same value (like Alice and Emma both earning 120,000), use a secondary column as a tie-breaker. You can mix directions:

-- Sort Department alphabetically (A-Z), then Salary from highest to lowest
SELECT department, salary, name
FROM employees
ORDER BY department ASC, salary DESC;

Output:

4. The NULL Handling Trap: NULLS FIRST vs NULLS LAST

A common gotcha when sorting descending is where missing (NULL) values land:

• PostgreSQL / Oracle / Snowflake: Treat NULL as larger than any value. In DESC sorting, NULLs appear at the top by default.
• MySQL / SQL Server: Treat NULL as smaller than any value. In DESC sorting, NULLs appear at the bottom by default.

Portable Fixes

To guarantee NULL values stay at the bottom across PostgreSQL and Oracle:

-- PostgreSQL / Oracle syntax
SELECT name, bonus_rate
FROM employees
ORDER BY bonus_rate DESC NULLS LAST;

For MySQL and SQL Server (which do not support NULLS LAST), use a boolean condition:

-- MySQL / SQL Server syntax
SELECT name, bonus_rate
FROM employees
ORDER BY (bonus_rate IS NULL) ASC, bonus_rate DESC;

5. Summary Cheat Sheet

6. Next Steps & Interactive Practice

Practice sorting and query execution on live datasets:

• Interactive Question: Try Customer Spend Ranking to practice sorting transactions.
• Topic Hub: Drill more queries in the Basic SQL Practice Hub.
• Execution Order: Learn where sorting happens in our guide to SQL Order of Execution.