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da5392134f
* Enforce an invariant in our dependency checker so that logical plans never have duplicate output attribute names or ids. * Fix ROW to not produce columns with duplicate names. * Fix ResolveUnionTypes to not create multiple synthetic field attributes for the same union type. * Add tests for commands using the same column name more than once. * Update docs w.r.t. how commands behave if they are used with duplicate column names.
64 lines
1.7 KiB
Text
64 lines
1.7 KiB
Text
[discrete]
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[[esql-dissect]]
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=== `DISSECT`
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`DISSECT` enables you to <<esql-process-data-with-dissect-and-grok,extract
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structured data out of a string>>.
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**Syntax**
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[source,esql]
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----
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DISSECT input "pattern" [APPEND_SEPARATOR="<separator>"]
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----
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*Parameters*
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`input`::
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The column that contains the string you want to structure. If the column has
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multiple values, `DISSECT` will process each value.
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`pattern`::
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A <<esql-dissect-patterns,dissect pattern>>.
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If a field name conflicts with an existing column, the existing column is dropped.
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If a field name is used more than once, only the rightmost duplicate creates a column.
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`<separator>`::
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A string used as the separator between appended values, when using the <<esql-append-modifier,append modifier>>.
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*Description*
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`DISSECT` enables you to <<esql-process-data-with-dissect-and-grok,extract
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structured data out of a string>>. `DISSECT` matches the string against a
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delimiter-based pattern, and extracts the specified keys as columns.
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Refer to <<esql-process-data-with-dissect>> for the syntax of dissect patterns.
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*Examples*
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// tag::examples[]
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The following example parses a string that contains a timestamp, some text, and
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an IP address:
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[source.merge.styled,esql]
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----
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include::{esql-specs}/docs.csv-spec[tag=basicDissect]
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----
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[%header.monospaced.styled,format=dsv,separator=|]
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|===
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include::{esql-specs}/docs.csv-spec[tag=basicDissect-result]
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|===
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By default, `DISSECT` outputs keyword string columns. To convert to another
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type, use <<esql-type-conversion-functions>>:
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[source.merge.styled,esql]
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----
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include::{esql-specs}/docs.csv-spec[tag=dissectWithToDatetime]
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----
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[%header.monospaced.styled,format=dsv,separator=|]
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|===
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include::{esql-specs}/docs.csv-spec[tag=dissectWithToDatetime-result]
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|===
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// end::examples[]
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