druid - 如何在 druid 中使用分页进行聚合查询（Druid 是一个面向列的分布式数据存储）。它是否支持带偏移量的查询？

是的，您可以使用选择查询进行分页。有关详细信息，请参见下面的德鲁伊文档链接 - http://druid.io/docs/latest/querying/select-query.html

例如。您可以发送以下查询 -

 {
       "queryType": "select",
       "dataSource": "wikipedia",
       "descending": "false",
       "dimensions":[],
       "metrics":[],
       "granularity": "all",
       "intervals": [
         "2013-01-01/2013-01-02"
       ],
       "pagingSpec":{"pagingIdentifiers": {}, "threshold":5}
     }

Result - 

[{
  "timestamp" : "2013-01-01T00:00:00.000Z",
  "result" : {
    "pagingIdentifiers" : {
      "wikipedia_2012-12-29T00:00:00.000Z_2013-01-10T08:00:00.000Z_2013-01-10T08:13:47.830Z_v9" : 4
    },
    "events" : [ {
      "segmentId" : "wikipedia_editstream_2012-12-29T00:00:00.000Z_2013-01-10T08:00:00.000Z_2013-01-10T08:13:47.830Z_v9",
      "offset" : 0,
      "event" : {
        "timestamp" : "2013-01-01T00:00:00.000Z",
        "robot" : "1",
        "namespace" : "article",
        "anonymous" : "0",
        "unpatrolled" : "0",
        "page" : "11._korpus_(NOVJ)",
        "language" : "sl",
        "newpage" : "0",
        "user" : "EmausBot",
        "count" : 1.0,
        "added" : 39.0,
        "delta" : 39.0,
        "variation" : 39.0,
        "deleted" : 0.0
      }
    }, {
      "segmentId" : "wikipedia_2012-12-29T00:00:00.000Z_2013-01-10T08:00:00.000Z_2013-01-10T08:13:47.830Z_v9",
      "offset" : 1,
      "event" : {
        "timestamp" : "2013-01-01T00:00:00.000Z",
        "robot" : "0",
        "namespace" : "article",
        "anonymous" : "0",
        "unpatrolled" : "0",
        "page" : "112_U.S._580",
        "language" : "en",
        "newpage" : "1",
        "user" : "MZMcBride",
        "count" : 1.0,
        "added" : 70.0,
        "delta" : 70.0,
        "variation" : 70.0,
        "deleted" : 0.0
      }
    }, {
      "segmentId" : "wikipedia_2012-12-29T00:00:00.000Z_2013-01-10T08:00:00.000Z_2013-01-10T08:13:47.830Z_v9",
      "offset" : 2,
      "event" : {
        "timestamp" : "2013-01-01T00:00:00.000Z",
        "robot" : "0",
        "namespace" : "article",
        "anonymous" : "0",
        "unpatrolled" : "0",
        "page" : "113_U.S._243",
        "language" : "en",
        "newpage" : "1",
        "user" : "MZMcBride",
        "count" : 1.0,
        "added" : 77.0,
        "delta" : 77.0,
        "variation" : 77.0,
        "deleted" : 0.0
      }
    }, {
      "segmentId" : "wikipedia_2012-12-29T00:00:00.000Z_2013-01-10T08:00:00.000Z_2013-01-10T08:13:47.830Z_v9",
      "offset" : 3,
      "event" : {
        "timestamp" : "2013-01-01T00:00:00.000Z",
        "robot" : "0",
        "namespace" : "article",
        "anonymous" : "0",
        "unpatrolled" : "0",
        "page" : "113_U.S._73",
        "language" : "en",
        "newpage" : "1",
        "user" : "MZMcBride",
        "count" : 1.0,
        "added" : 70.0,
        "delta" : 70.0,
        "variation" : 70.0,
        "deleted" : 0.0
      }
    }, {
      "segmentId" : "wikipedia_2012-12-29T00:00:00.000Z_2013-01-10T08:00:00.000Z_2013-01-10T08:13:47.830Z_v9",
      "offset" : 4,
      "event" : {
        "timestamp" : "2013-01-01T00:00:00.000Z",
        "robot" : "0",
        "namespace" : "article",
        "anonymous" : "0",
        "unpatrolled" : "0",
        "page" : "113_U.S._756",
        "language" : "en",
        "newpage" : "1",
        "user" : "MZMcBride",
        "count" : 1.0,
        "added" : 68.0,
        "delta" : 68.0,
        "variation" : 68.0,
        "deleted" : 0.0
      }
    } ]
  }
} ]

结果带有 pagingIdentifiers，您可以在下一个查询中传递它。

请注意，截至目前，它不适用于前 N 个查询。

更新 -

对于 top N 查询或聚合结果，目前没有直接获取分页结果的方法，但您可以使用更大的阈值和限制，并在客户端排除以前的结果。

druid - 如何在 druid 中使用分页进行聚合查询（Druid 是一个面向列的分布式数据存储）。它是否支持带偏移量的查询？

问题描述

解决方案

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