我在 SpagoBI 下使用 groovy 脚本。我想使用聚合。例如,我想执行以下聚合:
db.myCollection.aggregate(
[
{
$group : {
_id : { day: { $dayOfMonth: "$recvTime" } }
}
}
]
)
我试过了:
DBObject projectFields = new BasicDBObject('$dayOfMonth',"recvTime");
DBObject project=new BasicDBObject('$project',projectFields)
DBObject groupFields = new BasicDBObject( "_id",project);
DBObject group = new BasicDBObject('$group', groupFields);
iterable = db.getCollection('myCollection').aggregate(group)
我收到了这个错误:
An unexpected error occured while executing dataset: { "serverUsed" : "192.168.1.160:27017" , "errmsg" : "exception: invalid operator '$project'" , "code" : 15999 , "ok" : 0.0}
有任何想法吗?
更新:在 Mongo shell 中执行的查询
db['cygnus_/kurapath_enocean_power_enocean'].aggregate(
... [
... {
... $group : {
... _id : { day: { $dayOfMonth: "$recvTime" } }
... }
... }
... ]
... );
{ "_id" : { "day" : 9 } }
{ "_id" : { "day" : 8 } }
{ "_id" : { "day" : 7 } }
{ "_id" : { "day" : 4 } }
{ "_id" : { "day" : 3 } }
存储在 mongo db 中的数据:
db['cygnus_/kurapath_enocean_power_enocean'].find()
{ "_id" : ObjectId("55e81e9631d7791085668331"), "recvTime" : ISODate("2015-09-03T10:19:02Z"), "attrName" : "power", "attrType" : "string", "attrValue" : "2085.0" }
{ "_id" : ObjectId("55e81e9631d7791085668332"), "recvTime" : ISODate("2015-09-03T10:19:02Z"), "attrName" : "power", "attrType" : "string", "attrValue" : "2085.0" }
{ "_id" : ObjectId("55e81e9831d7791085668333"), "recvTime" : ISODate("2015-09-03T10:19:04Z"), "attrName" : "power", "attrType" : "string", "attrValue" : "2077.0" }