Can I use… last_value(… ignore nulls)


Apache DerbyBigQueryDb2 (LUW)H2MariaDBMySQLOracle DBPostgreSQLSQL ServerSQLite20052007200920112013201520172019202110.16.1.12.011.5.72.1.21410.88.0.2911gR21420193.39.0

The last_value(… ignore nulls) window function with the ignore nulls inside the parentheses is not standard SQL. It evaluates its argument in the rows defined by the over clause in reverse order and returns the first non-null value (if any).

SELECT LAST_VALUE(<expr> IGNORE NULLS) OVER (ORDER BY …)
  FROM …

Default Framing Applies

If there is no explicit framing clause the following default applies:

RANGE BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW

That means, the last_value() function cannot see beyond the ties to the current row. Open the frame to bring the last row into reach:

ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING

Normative References

Ignore nulls inside the parentheses of last_value() is not covered in the international SQL standard ISO/IEC 9075:2016-2. In standard SQL the ignore nulls clause follows the parentheses: last_value() ignore nulls.

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 winand.at.

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 »

Connect with Markus Winand

Markus Winand on LinkedInMarkus Winand on XINGMarkus Winand on Twitter
“modern SQL” 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