如何在 mongodb 指南针中使用 $setWindowFields

Question

我正在尝试在 mongodb 指南针中应用 $setWindowFields 聚合。但它不起作用。我正在关注this 教程。我正在尝试将以下代码转换为 mongodb 指南针聚合文档。

[{
    $setWindowFields: {
        partitionBy: "$source",
        sortBy: { ts: 1 },
        output: {
            "window.rollingCloseUSD": {
                $avg: "$closeUSD",
                window: {
                    documents: [-5, 0]
                }
            }
        }
    }
},
{
    $merge: {
        into: "stock_exchange_data_processed",
        whenMatched: "replace"
    }
}]

Answer 1

因为您的代码适用于指南针聚合

阶段 1 $setWindowFields

{
   partitionBy: "$source",
    sortBy: { ts: 1 },
    output: {
        "window.rollingCloseUSD": {
            $avg: "$closeUSD",
            window: {
                documents: [-5, 0]
            }
        }
    }
}

第 2 阶段 $merge

{
   into: "stock_exchange_data_processed",
        whenMatched: "replace"
}