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80 lines
2.5 KiB
Text
80 lines
2.5 KiB
Text
[discrete]
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[[esql-limit]]
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=== `LIMIT`
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The `LIMIT` processing command enables you to limit the number of rows that are
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returned.
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**Syntax**
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[source,esql]
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----
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LIMIT max_number_of_rows
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----
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*Parameters*
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`max_number_of_rows`::
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The maximum number of rows to return.
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*Description*
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The `LIMIT` processing command enables you to limit the number of rows that are
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returned.
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// tag::limitation[]
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For instance,
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```
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FROM index | WHERE field = "value"
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```
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is equivalent to:
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```
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FROM index | WHERE field = "value" | LIMIT 1000
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```
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Queries do not return more than 10,000 rows, regardless of the `LIMIT` command’s value. This is a configurable upper limit.
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To overcome this limitation:
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* Reduce the result set size by modifying the query to only return relevant data. Use <<esql-where>> to select a smaller subset of the data.
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* Shift any post-query processing to the query itself. You can use the {esql} <<esql-stats-by>> command to aggregate data in the query.
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The upper limit only applies to the number of rows that are output by the query, not to the number of documents it processes: the query runs on the full data set.
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Consider the following two queries:
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```
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FROM index | WHERE field0 == "value" | LIMIT 20000
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```
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and
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```
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FROM index | STATS AVG(field1) BY field2 | LIMIT 20000
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```
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In both cases, the filtering by `field0` in the first query or the grouping by `field2` in the second is applied over all the documents present in the `index`, irrespective of their number or indexes size. However, both queries will return at most 10,000 rows, even if there were more rows available to return.
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The default and maximum limits can be changed using these dynamic cluster settings:
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* `esql.query.result_truncation_default_size`
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* `esql.query.result_truncation_max_size`
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However, doing so involves trade-offs. A larger result-set involves a higher memory pressure and increased processing times; the internode traffic within and across clusters can also increase.
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These limitations are similar to those enforced by the <<paginate-search-results>>.
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[%header.monospaced.styled,format=dsv,separator=|]
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|===
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Functionality | Search | {esql}
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Results returned by default | 10 | 1.000
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Default upper limit | 10,000 | 10,000
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Specify number of results | `size` | `LIMIT`
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Change default number of results | n/a | esql.query.result_truncation_default_size
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Change default upper limit | index-max-result-window | esql.query.result_truncation_max_size
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|===
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// end::limitation[]
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*Example*
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[source,esql]
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----
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include::{esql-specs}/limit.csv-spec[tag=basic]
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----
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