在 groups 中定义数据聚合方式，Group 数据结构为 Array<Object Group>。

Object Group 数据结构

数据表 service :

Gou Query DSL:

function Groups() {
  var query = new Query();
  var data = query.Get({
    select: ["type as 类型", "city as 城市", ":COUNT(id) as 数量"],
    from: "service",
    groups: [
      { field: "type", comment: "按类型统计" },
      { field: "city", comment: "按城市统计" },
    ],
  });
  return data;
}

解析后的 SQL语句 为(MySQL):

 SELECT `type` AS `类型`, `city` AS `城市`, COUNT(`id`) AS `数量`
 FROM `service`
 GROUP BY `type`, `city`

查询结果为:

聚合函数按特定算法，对一组数据记录统计，返回一个数值，一般用于聚合查询。

在通常情况下，只需指定聚合字段即可，可使用 Array<Field Expression> 结构描述； 亦可使用 Field Expression 类型描述，多个用 , 分割。

以下描述解析结果相同。

完整描述

{
  "select": ["kind as 类型", "city as 城市", ":SUM(amount) as 数量"],
  "from": "service",
  "groups": [
    { "field": "kind", "comment": "按类型统计" },
    { "field": "city", "comment": "按城市统计" }
  ]
}

简化为 Array<Field Expression>

{
  "select": ["kind as 类型", "city as 城市", ":SUM(amount) as 数量"],
  "from": "service",
  "groups": ["kind", { "field": "city", "comment": "按城市统计" }]
}

简化为 Field Expression

{
  "select": ["kind as 类型", "city as 城市", ":SUM(amount) as 数量"],
  "from": "service",
  "groups": "kind,city"
}

在对 JSON Array 字段聚合查询时，需要先连接 JSON Table，再对连接后的数据表进行聚合查询。可以简写为直接按 JSON Array 字段聚合。

数据表 service :

Query DSL:

{
  "select": [
    "@industries as 行业",
    "@pricing[*].name as 计费方式",
    ":SUM(amount) as 数量"
  ],
  "from": "service",
  "groups": [
    { "field": "行业", "rollup": "全部行业" },
    { "field": "计费方式", "rollup": "所有计费方式" }
  ]
}

解析后的 SQL语句 (MySQL8):

SELECT
  IF(GROUPING(`行业`), '全部行业', `行业`)  AS `行业`,
  IF(GROUPING(`计费方式`), '所有计费方式', `计费方式`) AS `计费方式`,
  SUM(`amount`) AS `数量`
FROM `service`
  JOIN JSON_TABLE(`service`.`industries`, '$[*]' columns (`行业` varchar(50) path '$') ) as industries
  JOIN JSON_TABLE(`service`.`pricing`, '$[*]' columns (`计费方式` varchar(50) path '$.name') ) as pricing
GROUP by `行业`, `计费方式` WITH ROLLUP

返回结果: