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Wuwan, Qi
050b395397
Reviewed-by: Kacur, Michal <michal.kacur@t-systems.com> Co-authored-by: Wuwan, Qi <wuwanqi1@noreply.gitea.eco.tsi-dev.otc-service.com> Co-committed-by: Wuwan, Qi <wuwanqi1@noreply.gitea.eco.tsi-dev.otc-service.com>
48 lines
1.7 KiB
HTML
48 lines
1.7 KiB
HTML
<a name="css_01_0175"></a><a name="css_01_0175"></a>
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<h1 class="topictitle1">High-cardinality Field Histogram Aggregation</h1>
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<div id="body0000001081905261"><p id="css_01_0175__p16687121514217">High-cardinality fields are usually used for histogram grouping and aggregation instead of single-point grouping and aggregation. For example, collecting the statistics of logs at a certain period. Assume that the following query statement exists:</p>
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<pre class="screen" id="css_01_0175__screen39844394244">POST testindex/_search?pretty
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{
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"size": 0,
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"aggs": {
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"avg_score": {
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"avg": {
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"field": "score"
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},
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"aggs": {
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"groupbytime": {
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"date_histogram": {
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"field": "timestamp",
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"calendar_interval": "day"
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}
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}
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}
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}
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}
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}</pre>
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<p id="css_01_0175__en-us_topic_0000001268394293_p8060118">This query groups the field <strong id="css_01_0175__b1693212561881">timestamp</strong> using a histogram and calculates the average score. <strong id="css_01_0175__b13636195920">timestamp</strong> is a typical high-cardinality field. To use the enhanced aggregation for the preceding query, set parameters as follows:</p>
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<pre class="screen" id="css_01_0175__screen95703147257">// Configure an index
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"settings" : {
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"index" : {
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"search" : {
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"turbo" : {
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"enabled" : "true" // Enable optimization
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}
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},
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"sort" : { // Specify a sorting key
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"field" : [
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"timestamp"
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]
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}
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}
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}
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</pre>
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</div>
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<div>
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<div class="familylinks">
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<div class="parentlink"><strong>Parent topic:</strong> <a href="css_01_0172.html">Enhanced Aggregation</a></div>
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</div>
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</div>
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