我在mongodb中的集合类似于SQL中的下表:
感情(陪伴、感情)
现在,我需要执行如下查询:
SELECT
Company,
SUM(CASE WHEN Sentiment >0 THEN Sentiment ELSE 0 END) AS SumPosSenti,
SUM(CASE WHEN Sentiment <0 THEN Sentiment ELSE 0 END) AS SumNegSenti
FROM Sentiments
GROUP BY Company
我应该怎么做才能在Mongo中编写这个查询?我被以下问题困住了:
db.Sentiments.aggregate(
{ $project: {_id:0, Company:1, Sentiment: 1} },
{ $group: {_id: "$Company", SumPosSenti: {$sum: ? }, SumNegSenti: {$sum: ? } } }
);