德鲁伊：如何在不使用聚合函数的情况下将数值数据添加到度量

Question

场景是我想设置股票报价服务器并将报价数据保存到德鲁伊。

我的要求是通过查询获得所有股票的最新价格。

但是我注意到德鲁伊的查询界面（如时间序列）仅适用于指标字段，而不是维度字段。

所以我考虑让价格成为其中一个指标，但不需要汇总。

我该怎么做？

有什么建议吗？

这是我的宁静配置文件。

{
  "dataSources" : {
     "stock-index-topic" : {
      "spec" : {
        "dataSchema" : {
          "dataSource" : "stock-index-topic",
          "parser" : {
            "type" : "string",
            "parseSpec" : {
              "timestampSpec" : {
                "column" : "timestamp",
                "format" : "auto"
              },
              "dimensionsSpec" : {
                "dimensions" : ["code","name","acronym","market","tradeVolume","totalValueTraded","preClosePx","openPrice","highPrice","lowPrice","latestPrice","closePx"],
                "dimensionExclusions" : [
                  "timestamp",
                  "value"
                ]
              },
              "format" : "json"
            }
          },
          "granularitySpec" : {
            "type" : "uniform",
            "segmentGranularity" : "HOUR",
            "queryGranularity" : "SECOND",
          },
          "metricsSpec" : [
            {
              "name" : "firstPrice",
              "type" : "doubleFirst",
              "fieldName" : "tradePrice"
            },{
              "name" : "lastPrice",
              "type" : "doubleLast",
              "fieldName" : "tradePrice"
            }, {
              "name" : "minPrice",
              "type" : "doubleMin",
              "fieldName" : "tradePrice"
            }, {
              "name" : "maxPrice",
              "type" : "doubleMax",
              "fieldName" : "tradePrice"
            }
          ]
        },
        "ioConfig" : {
          "type" : "realtime"
        },
        "tuningConfig" : {
          "type" : "realtime",
          "maxRowsInMemory" : "100000",
          "intermediatePersistPeriod" : "PT10M",
          "windowPeriod" : "PT10M"
        }
      },
      "properties" : {
        "task.partitions" : "1",
        "task.replicants" : "1",
        "topicPattern" : "stock-index-topic"
      }
    }
  },
  "properties" : {
    "zookeeper.connect" : "localhost:2181",
    "druid.discovery.curator.path" : "/druid/discovery",
    "druid.selectors.indexing.serviceName" : "druid/overlord",
    "commit.periodMillis" : "15000",
    "consumer.numThreads" : "2",
    "kafka.zookeeper.connect" : "localhost:2181",
    "kafka.group.id" : "tranquility-kafka"
  }
}