将 Sql 查询转换为 Mongodb 查询

Question

i have a query in sql that i want to convert in mongodb with python pymongo.

cursor=execute("select avg(id13)::numeric(10,2) from timestamppsql where timestamp1<='2011-01-01 00:05:00'")

This is the code i tested in mongodb:

cursor=mydb1.mongodbtime.aggregate({
    '$group': {
        "timestamp1":{ "$lte" : datetime.strptime("2011-01-01 00:05:00", "%Y-%m-%d %H:%M:%S") },

        "avg_id13": {"$avg": "$id13"}
    }
})

The output is this:

pipeline must be a list

How can i fix that?Any help would be appreciated.

Answer 1

The argument to aggregate is an array, not a mapping. Put your mapping into an array.