Sorting Retrieved Column Data

By default, a SELECT query returns rows in no guaranteed order. The ORDER BY clause lets you sort the results by one or more columns, alphabetically, numerically, or chronologically, so the output is easier to read and analyze.

Basic sorting

Add ORDER BY after the table name, followed by the column to sort on:

SELECT first_name, last_name
FROM customers
ORDER BY last_name;

This lists customers alphabetically by last name. Sorting is ascending (A to Z, smallest to largest) unless you say otherwise.

Ascending and descending order

You can state the direction explicitly with ASC (ascending) or DESC (descending):

SELECT first_name, last_name
FROM customers
ORDER BY last_name DESC;

Here the results run from Z to A. DESC is often used to put the most recent dates or the highest numbers first.

Sorting by multiple columns

List several columns, separated by commas, to break ties. The database sorts by the first column, then uses the next column to order rows that share the same value:

SELECT first_name, last_name, city
FROM customers
ORDER BY city, last_name;

This groups customers by city, and within each city orders them by last name. Each column can have its own ASC or DESC.