by Markus Winand.

MySQL Example Scripts for “Partial Results”

This section contains the create and insert statements to run the examples from Chapter 7, “Partial Results in a MySQL database.

Querying Top-N Rows

An indexed Top-N query doesn't show a “filesort” operation in the Extras column:

  FROM sales
 ORDER BY sale_date DESC

| id | table | type  | key         | rows   | Extra |
|  1 | sales | index | sales_dt_pr | 836092 |       | 

About the Author

Photo of Markus Winand

Markus Winand is the SQL Renaissance Ambassador. He is on a mission to introduce developers to the evolution of SQL in the 21st century. Markus can be hired as trainer, speaker and consultant via

Buy his Book on Amazon

Cover of “SQL Performance Explained”: Squirrel running on grass

The essence of SQL tuning in 200 pages

Buy on Amazon
(paperback only)

Paperback and PDF also available at Markus’ store.

Hire Markus

Markus offers SQL training and consulting for developers working at companies of any size.
Learn more »

“Use The Index, Luke!” by Markus Winand is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 Unported License.
Legal | Contact | NO WARRANTY | Trademarks | Privacy and GDPR | CC-BY-NC-ND 3.0 license