97 lines
2.5 KiB
Plaintext
97 lines
2.5 KiB
Plaintext
[[search-aggregations-bucket-nested-aggregation]]
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=== Nested Aggregation
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A special single bucket aggregation that enables aggregating nested documents.
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For example, lets say we have an index of products, and each product holds the list of resellers - each having its own
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price for the product. The mapping could look like:
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[source,console]
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--------------------------------------------------
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PUT /products
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{
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"mappings": {
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"properties" : {
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"resellers" : { <1>
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"type" : "nested",
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"properties" : {
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"reseller" : { "type" : "text" },
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"price" : { "type" : "double" }
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}
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}
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}
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}
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}
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--------------------------------------------------
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<1> `resellers` is an array that holds nested documents.
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The following request adds a product with two resellers:
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[source,console]
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--------------------------------------------------
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PUT /products/_doc/0
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{
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"name": "LED TV", <1>
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"resellers": [
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{
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"reseller": "companyA",
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"price": 350
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},
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{
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"reseller": "companyB",
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"price": 500
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}
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]
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}
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--------------------------------------------------
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// TEST[s/PUT \/products\/_doc\/0/PUT \/products\/_doc\/0\?refresh/]
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// TEST[continued]
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<1> We are using a dynamic mapping for the `name` attribute.
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The following request returns the minimum price a product can be purchased for:
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[source,console]
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--------------------------------------------------
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GET /products/_search
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{
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"query" : {
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"match" : { "name" : "led tv" }
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},
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"aggs" : {
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"resellers" : {
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"nested" : {
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"path" : "resellers"
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},
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"aggs" : {
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"min_price" : { "min" : { "field" : "resellers.price" } }
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}
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}
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}
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}
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--------------------------------------------------
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// TEST[s/GET \/products\/_search/GET \/products\/_search\?filter_path=aggregations/]
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// TEST[continued]
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As you can see above, the nested aggregation requires the `path` of the nested documents within the top level documents.
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Then one can define any type of aggregation over these nested documents.
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Response:
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[source,console-result]
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--------------------------------------------------
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{
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...
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"aggregations": {
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"resellers": {
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"doc_count": 2,
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"min_price": {
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"value": 350
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}
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}
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}
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}
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--------------------------------------------------
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// TESTRESPONSE[s/\.\.\.//]
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// TESTRESPONSE[s/: [0-9]+/: $body.$_path/]
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