MongoDB bucket操作，其类型为unhashable: 'dict' in mongoEngine。

Question

下面是一些示例文档（我只显示了使用过的文件，文档中还有其他字段）。

{"id":1111,"info":{"score":90,"class":"algorithm","room":101}}
{"id":1112,"info":{"score":60,"class":"java","room":401}}
{"id":1113,"info":{"score":100,"class":"python","room":301}}

我想做的是计算分数分布，我使用了桶操作，根据 https:/docs.mongodb.commanualreferenceoperatoraggregationbucketindex.html。。

pipeline = {
        {"$match": {"_id": ObjectId(_id)}},
        {"$bucket": {
            "groupBy": "$info.score",
            "boundaries": [0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100],
            "output": {
                "count": {"$sum": 1}
            }
        }}
    }
score_distribution = list(Students.objects.aggregate(*pipeline))

但是，我遇到了错误，我找不到类型错误的原因，谁能给点建议？

"count": {"$sum": 1}
TypeError: unhashable type: 'dict'

我找不到类型错误的原因，谁能给点建议？

Answer 1

对不起各位，我犯了一个超级编辑错误，管道应该是数组而不是dict。

pipeline = [
        {"$match": {"_id": ObjectId(_id)}},
        {"$bucket": {
            "groupBy": "$info.score",
            "boundaries": [0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100],
            "output": {
                "count": {"$sum": 1}
            }
        }}
    ]