elasticsearch/docs/reference/esql/processing-commands/where.asciidoc

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[discrete]
[[esql-where]]
=== `WHERE`
**Syntax**
[source,esql]
----
WHERE expression
----
*Parameters*
`expression`::
A boolean expression.
*Description*
The `WHERE` processing command produces a table that contains all the rows from
the input table for which the provided condition evaluates to `true`.
*Examples*
[source,esql]
----
include::{esql-specs}/docs.csv-spec[tag=where]
----
Which, if `still_hired` is a boolean field, can be simplified to:
[source,esql]
----
include::{esql-specs}/docs.csv-spec[tag=whereBoolean]
----
Use date math to retrieve data from a specific time range. For example, to
retrieve the last hour of logs:
[source,esql]
----
include::{esql-specs}/date.csv-spec[tag=docsNowWhere]
----
`WHERE` supports various <<esql-functions,functions>>. For example the
<<esql-length>> function:
[source,esql]
----
include::{esql-specs}/docs.csv-spec[tag=whereFunction]
----
For a complete list of all functions, refer to <<esql-functions>>.
include::../functions/predicates.asciidoc[tag=body]
include::../functions/like.asciidoc[tag=body]
include::../functions/rlike.asciidoc[tag=body]
include::../functions/in.asciidoc[tag=body]
For a complete list of all operators, refer to <<esql-operators>>.