elasticsearch/docs/reference/esql/functions/count.asciidoc

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[discrete]
[[esql-agg-count]]
=== `COUNT`
*Syntax*
[source,esql]
----
COUNT([expression])
----
*Parameters*
`expression`::
Expression that outputs values to be counted.
If omitted, equivalent to `COUNT(*)` (the number of rows).
*Description*
Returns the total number (count) of input values.
*Supported types*
Can take any field type as input.
*Examples*
[source.merge.styled,esql]
----
include::{esql-specs}/stats.csv-spec[tag=count]
----
[%header.monospaced.styled,format=dsv,separator=|]
|===
include::{esql-specs}/stats.csv-spec[tag=count-result]
|===
To count the number of rows, use `COUNT()` or `COUNT(*)`:
[source.merge.styled,esql]
----
include::{esql-specs}/docs.csv-spec[tag=countAll]
----
[%header.monospaced.styled,format=dsv,separator=|]
|===
include::{esql-specs}/docs.csv-spec[tag=countAll-result]
|===
The expression can use inline functions. This example splits a string into
multiple values using the `SPLIT` function and counts the values:
[source.merge.styled,esql]
----
include::{esql-specs}/stats.csv-spec[tag=docsCountWithExpression]
----
[%header.monospaced.styled,format=dsv,separator=|]
|===
include::{esql-specs}/stats.csv-spec[tag=docsCountWithExpression-result]
|===
[[esql-agg-count-or-null]]
To count the number of times an expression returns `TRUE` use
a <<esql-where>> command to remove rows that shouldn't be included:
[source.merge.styled,esql]
----
include::{esql-specs}/stats.csv-spec[tag=count-where]
----
[%header.monospaced.styled,format=dsv,separator=|]
|===
include::{esql-specs}/stats.csv-spec[tag=count-where-result]
|===
To count the same stream of data based on two different expressions
use the pattern `COUNT(<expression> OR NULL)`:
[source.merge.styled,esql]
----
include::{esql-specs}/stats.csv-spec[tag=count-or-null]
----
[%header.monospaced.styled,format=dsv,separator=|]
|===
include::{esql-specs}/stats.csv-spec[tag=count-or-null-result]
|===