有个需要，在sql中的计算形式是：

sum(cost) / 100 / sum(view_count) * 1000

统计出均匀千次展示均价，老本按分存储。

在es中须要聚合cost和view_count 之后再运算。折腾了半天，记录下：

"aggs" => [    'total_cost_count' => [        'sum' => [            'field' => 'cost'        ]    ],    'total_view_count' => [        'sum' => [            'field' => 'view_count'        ]    ],    '(total_cost / total_view)' => [        'bucket_script' => [            'buckets_path' => [                'cost' => 'total_cost_count',                'view_count' => 'total_view_count',            ],            'script' => [                'source' => "params.cost / params.unit / params.view_count * params.days",                'params' => [                    'unit' => 100,                    'days' => 1000,                ]            ]        ]    ]],

调试过程中报错信息：

  • Only sibling pipeline aggregations are allowed at the top level

    • 在顶层只容许兄弟管道聚合。也就是聚合运算只能在同一个桶内。

参考文档：https://www.elastic.co/guide/en/elasticsearch/painless/7.13/painless-bucket-script-agg-context.html