elasticsearch/docs/reference/esql/esql-kibana.asciidoc
2024-02-21 09:25:25 +01:00

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[[esql-kibana]]
=== Using {esql} in {kib}
++++
<titleabbrev>Using {esql} in {kib}</titleabbrev>
++++
You can use {esql} in {kib} to query and aggregate your data, create
visualizations, and set up alerts.
This guide shows you how to use {esql} in Kibana. To follow along with the
queries, load the "Sample web logs" sample data set by clicking *Try sample
data* from the {kib} Home, selecting *Other sample data sets*, and clicking *Add
data* on the *Sample web logs* card.
[discrete]
[[esql-kibana-get-started]]
=== Get started with {esql}
// tag::esql-mode[]
To get started with {esql} in Discover, open the main menu and select
*Discover*. Next, from the Data views menu, select *Try ES|QL*.
image::images/esql/esql-data-view-menu.png[align="center",width=33%]
// end::esql-mode[]
The ability to select {esql} from the Data views menu can be enabled and
disabled using the `discover:enableESQL` setting from
{kibana-ref}/advanced-options.html[Advanced Settings].
[discrete]
[[esql-kibana-query-bar]]
=== The query bar
After switching to {esql} mode, the query bar shows a sample query. For example:
[source,esql]
----
from kibana_sample_data_logs | limit 10
----
Every query starts with a <<esql-commands,source command>>. In this query, the
source command is <<esql-from>>. `FROM` retrieves data from data streams, indices, or
aliases. In this example, the data is retrieved from `kibana_sample_data_logs`.
A source command can be followed by one or more <<esql-commands,processing
commands>>. In this query, the processing command is <<esql-limit>>. `LIMIT`
limits the number of rows that are retrieved.
TIP: Click the help icon (image:images/esql/esql-icon-help.svg[]) to open the
in-product reference documentation for all commands and functions.
// tag::autocomplete[]
To make it easier to write queries, auto-complete offers suggestions with
possible commands and functions:
image::images/esql/esql-kibana-auto-complete.png[align="center"]
// end::autocomplete[]
[NOTE]
====
{esql} keywords are case-insensitive. The following query is identical to the
previous one:
[source,esql]
----
FROM kibana_sample_data_logs | LIMIT 10
----
====
[discrete]
==== Expand the query bar
For readability, you can put each processing command on a new line. The
following query is identical to the previous one:
[source,esql]
----
FROM kibana_sample_data_logs
| LIMIT 10
----
// tag::compact[]
To make it easier to write multi-line queries, click the double-headed arrow
button (image:images/esql/esql-icon-expand-query-bar.svg[]) to expand the query
bar:
image::images/esql/esql-expanded-query-bar.png[align="center"]
To return to a compact query bar, click the minimize editor button
(image:images/esql/esql-icon-minimize-query-bar.svg[]).
// end::compact[]
[discrete]
==== Warnings
A query may result in warnings, for example when querying an unsupported field
type. When that happens, a warning symbol is shown in the query bar. To see the
detailed warning, expand the query bar, and click *warnings*.
[discrete]
[[esql-kibana-results-table]]
=== The results table
For the example query, the results table shows 10 rows. Omitting the `LIMIT`
command, the results table defaults to up to 1000 rows. Using `LIMIT`, you can
increase the limit to up to 10,000 rows.
NOTE: the 10,000 row limit only applies to the number of rows that are retrieved
by the query and displayed in Discover. Any query or aggregation runs on the
full data set.
Each row shows two columns for the example query: a column with the `@timestamp`
field and a column with the full document. To display specific fields from the
documents, use the <<esql-keep>> command:
[source,esql]
----
FROM kibana_sample_data_logs
| KEEP @timestamp, bytes, geo.dest
----
To display all fields as separate columns, use `KEEP *`:
[source,esql]
----
FROM kibana_sample_data_logs
| KEEP *
----
NOTE: The maximum number of columns in Discover is 50. If a query returns more
than 50 columns, Discover only shows the first 50.
[discrete]
==== Sorting
To sort on one of the columns, click the column name you want to sort on and
select the sort order. Note that this performs client-side sorting. It only
sorts the rows that were retrieved by the query, which may not be the full
dataset because of the (implicit) limit. To sort the full data set, use the
<<esql-sort>> command:
[source,esql]
----
FROM kibana_sample_data_logs
| KEEP @timestamp, bytes, geo.dest
| SORT bytes DESC
----
[discrete]
[[esql-kibana-time-filter]]
=== Time filtering
To display data within a specified time range, use the
{kibana-ref}/set-time-filter.html[time filter]. The time filter is only enabled
when the indices you're querying have a field called `@timestamp`.
If your indices do not have a timestamp field called `@timestamp`, you can limit
the time range using the <<esql-where>> command and the <<esql-now>> function.
For example, if the timestamp field is called `timestamp`, to query the last 15
minutes of data:
[source,esql]
----
FROM kibana_sample_data_logs
| WHERE timestamp > NOW() - 15minutes
----
[discrete]
[[esql-kibana-visualizations]]
=== Analyze and visualize data
Between the query bar and the results table, Discover shows a date histogram
visualization. If the indices you're querying do not contain an `@timestamp`
field, the histogram is not shown.
The visualization adapts to the query. A query's nature determines the type of
visualization. For example, this query aggregates the total number of bytes per
destination country:
[source,esql]
----
FROM kibana_sample_data_logs
| STATS total_bytes = SUM(bytes) BY geo.dest
| SORT total_bytes DESC
| LIMIT 3
----
The resulting visualization is a bar chart showing the top 3 countries:
image::images/esql/esql-kibana-bar-chart.png[align="center"]
To change the visualization into another type, click the visualization type
dropdown:
image::images/esql/esql-kibana-visualization-type.png[align="center",width=33%]
To make other changes to the visualization, like the axes and colors, click the
pencil button (image:images/esql/esql-icon-edit-visualization.svg[]). This opens
an in-line editor:
image::images/esql/esql-kibana-in-line-editor.png[align="center"]
You can save the visualization to a new or existing dashboard by clicking the
save button (image:images/esql/esql-icon-save-visualization.svg[]). Once saved
to a dashboard, you can continue to make changes to visualization. Click the
options button in the top-right (image:images/esql/esql-icon-options.svg[]) and
select *Edit ESQL visualization* to open the in-line editor:
image::images/esql/esql-kibana-edit-on-dashboard.png[align="center"]
[discrete]
[[esql-kibana-enrich]]
=== Create an enrich policy
The {esql} <<esql-enrich>> command enables you to <<esql-enrich-data,enrich>>
your query dataset with fields from another dataset. Before you can use
`ENRICH`, you need to <<esql-set-up-enrich-policy,create and execute an enrich
policy>>. If a policy exists, it will be suggested by auto-complete. If not,
click *Click to create* to create one.
image::images/esql/esql-kibana-enrich-autocomplete.png[align="center"]
Next, you can enter a policy name, the policy type, source indices, and
optionally a query:
image::images/esql/esql-kibana-enrich-step-1.png[align="center",width="50%"]
Click *Next* to select the match field and enrich fields:
image::images/esql/esql-kibana-enrich-step-2.png[align="center",width="50%"]
Finally, click *Create and execute*.
Now, you can use the enrich policy in an {esql} query:
image::images/esql/esql-kibana-enriched-data.png[align="center"]
[discrete]
[[esql-kibana-alerting-rule]]
=== Create an alerting rule
You can use {esql} queries to create alerts. From Discover, click *Alerts* and
select *Create search threshold rule*. This opens a panel that enables you to
create a rule using an {esql} query. Next, you can test the query, add a
connector, and save the rule.
image::images/esql/esql-kibana-create-rule.png[align="center",width=50%]
[discrete]
[[esql-kibana-limitations]]
=== Limitations
// tag::limitations[]
* The user interface to filter data is not enabled when Discover is in {esql}
mode. To filter data, write a query that uses the <<esql-where>> command
instead.
* In {esql} mode, clicking a field in the field list in Discover does not show
quick statistics for that field.
* Discover shows no more than 10,000 rows. This limit only applies to the number
of rows that are retrieved by the query and displayed in Discover. Queries and
aggregations run on the full data set.
* Discover shows no more than 50 columns. If a query returns
more than 50 columns, Discover only shows the first 50.
* CSV export from Discover shows no more than 10,000 rows. This limit only applies to the number
of rows that are retrieved by the query and displayed in Discover. Queries and
aggregations run on the full data set.
* Querying many indices at once without any filters can cause an error in
kibana which looks like `[esql] > Unexpected error from Elasticsearch: The
content length (536885793) is bigger than the maximum allowed string
(536870888)`. The response from {esql} is too long. Use <<esql-drop>> or
<<esql-keep>> to limit the number of fields returned.
// end::limitations[]