【发布时间】:2014-10-18 01:42:38
【问题描述】:
需要对数据库 mongodb 执行查询,从而按时间范围生成一组结果。我正在使用 pymongo。我的查询如下:
query = {"$and": [
{"id_node": id_node}
{"port": port},
{"datetime": {"$gte": self.hourBegin}}
{"datetime": {"$lte": self.now}}
]}
listResults = db.mycollection.find (query)
我也试过这种方式:
query = {"id_node": int(id_node)
"port": port,
"datetime": {"$gte": self.hourBegin, "$lte": self.now}}
listResults = db.mycollection.find (query)
但结果总是空的。直接在mongodb中测试,结果为空。我确定数据库中存在我正在研究的时间范围内的数据。
可能的结果列表:
{ "_id" : ObjectId("543618c6e7b9914c35266128"), "lab" : "2", "port" : "A1", "id_node" : 1, "datetime" : ISODate("2014-09-26T18:28:04Z"), "valor" : "22.00", "sensor" : "2" }
{ "_id" : ObjectId("543618c6e7b9914c35266129"), "lab" : "2", "port" : "A0", "id_node" : 1, "datetime" : ISODate("2014-09-26T18:28:04Z"), "valor" : "0", "sensor" : "1" }
{ "_id" : ObjectId("543618c6e7b9914c3526612c"), "lab" : "2", "port" : "A1", "id_node" : 1, "datetime" : ISODate("2014-09-26T18:28:06Z"), "valor" : "22.00", "sensor" : "2" }
{ "_id" : ObjectId("543618c6e7b9914c3526612d"), "lab" : "2", "port" : "A0", "id_node" : 1, "datetime" : ISODate("2014-09-26T18:28:06Z"), "valor" : "0", "sensor" : "1" }
{ "_id" : ObjectId("543618c7e7b9914c35266130"), "lab" : "2", "port" : "A1", "id_node" : 1, "datetime" : ISODate("2014-09-26T18:28:08Z"), "valor" : "22.00", "sensor" : "2" }
{ "_id" : ObjectId("543618c7e7b9914c35266131"), "lab" : "2", "port" : "A0", "id_node" : 1, "datetime" : ISODate("2014-09-26T18:28:08Z"), "valor" : "0", "sensor" : "1" }
{ "_id" : ObjectId("543618c7e7b9914c35266134"), "lab" : "2", "port" : "A1", "id_node" : 1, "datetime" : ISODate("2014-09-26T18:28:10Z"), "valor" : "22.00", "sensor" : "2" }
{ "_id" : ObjectId("543618c7e7b9914c35266135"), "lab" : "2", "port" : "A0", "id_node" : 1, "datetime" : ISODate("2014-09-26T18:28:10Z"), "valor" : "0", "sensor" : "1" }
{ "_id" : ObjectId("543618c7e7b9914c35266138"), "lab" : "2", "port" : "A1", "id_node" : 1, "datetime" : ISODate("2014-09-26T18:28:12Z"), "valor" : "22.00", "sensor" : "2" }
{ "_id" : ObjectId("543618c7e7b9914c35266139"), "lab" : "2", "port" : "A0", "id_node" : 1, "datetime" : ISODate("2014-09-26T18:28:12Z"), "valor" : "0", "sensor" : "1" }
【问题讨论】:
-
删除查询运算符中的空格。使用
$gte而不是$ gte。$lte也一样。 -
也使用查询的第二种变体,但您的查询对象无效。
id_no字段缺少:。 -
您能否更新您的问题以包含您希望包含在结果中的示例文档?
-
好的,我做了,添加示例文档。
-
self.hourBegin和self.now的类型是什么?他们看起来怎么样?