73 lines
2.1 KiB
Plaintext
73 lines
2.1 KiB
Plaintext
[[mapping-store]]
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=== `store`
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By default, field values are <<mapping-index,indexed>> to make them searchable,
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but they are not _stored_. This means that the field can be queried, but the
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original field value cannot be retrieved.
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Usually this doesn't matter. The field value is already part of the
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<<mapping-source-field,`_source` field>>, which is stored by default. If you
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only want to retrieve the value of a single field or of a few fields, instead
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of the whole `_source`, then this can be achieved with
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<<search-request-source-filtering,source filtering>>.
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In certain situations it can make sense to `store` a field. For instance, if
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you have a document with a `title`, a `date`, and a very large `content`
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field, you may want to retrieve just the `title` and the `date` without having
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to extract those fields from a large `_source` field:
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[source,js]
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--------------------------------------------------
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PUT my_index
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{
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"mappings": {
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"my_type": {
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"properties": {
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"title": {
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"type": "text",
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"store": true <1>
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},
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"date": {
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"type": "date",
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"store": true <1>
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},
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"content": {
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"type": "text"
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}
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}
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}
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}
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}
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PUT my_index/my_type/1
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{
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"title": "Some short title",
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"date": "2015-01-01",
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"content": "A very long content field..."
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}
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GET my_index/_search
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{
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"stored_fields": [ "title", "date" ] <2>
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}
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--------------------------------------------------
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// CONSOLE
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<1> The `title` and `date` fields are stored.
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<2> This request will retrieve the values of the `title` and `date` fields.
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[NOTE]
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.Stored fields returned as arrays
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======================================
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For consistency, stored fields are always returned as an _array_ because there
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is no way of knowing if the original field value was a single value, multiple
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values, or an empty array.
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If you need the original value, you should retrieve it from the `_source`
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field instead.
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======================================
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Another situation where it can make sense to make a field stored is for those
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that don't appear in the `_source` field (such as <<copy-to,`copy_to` fields>>).
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