[[esql-is_null]]
=== `IS_NULL`
Returns a boolean that indicates whether its input is `null`.

[source.merge.styled,esql]
----
include::{esql-specs}/docs.csv-spec[tag=isNull]
----
[%header.monospaced.styled,format=dsv,separator=|]
|===
include::{esql-specs}/docs.csv-spec[tag=isNull-result]
|===

Combine this function with `NOT` to filter out any `null` data:

[source.merge.styled,esql]
----
include::{esql-specs}/docs.csv-spec[tag=notIsNull]
----
[%header.monospaced.styled,format=dsv,separator=|]
|===
include::{esql-specs}/docs.csv-spec[tag=notIsNull-result]
|===