统计Mongo数组中相同对象的属性之和
统计Mongo数组中相同对象的属性之和
需求
需要统计app端用户的行为，按天分表，存入mongo。每次用户进行操作的时候，将数据存入app本地，下次用户启动的时候，提交存入mongo，删除app本地缓存。那么用户这个行为的文档就算是很复杂了。举个例子，存入mongo中文档为
/* 1 */
{
"_id" : ObjectId("5b8c996e5f814eb3c37eb49b"),
"userId" : 12323.0,
"appPlatform" : "ios",
"shortcutEntrance" : [
{
"entranceName" : "入口1",
"gmtCreate" : "2018-09-03 10:00:00"
},
{
"entranceName" : "入口2",
"gmtCreate" : "2018-09-03 10:00:00"
}
],
"classData" : [
{
"classId" : 123.0,
"position" : "left",
"gmtCreate" : "2018-09-03 10:00:00"
},
{
"classId" : 12356.0,
"position" : "right",
"gmtCreate" : "2018-09-03 10:00:00"
}
],
"channelVisit" : [
{
"channelType" : 2.0,
"gmtCreate" : "2018-09-03 10:00:00"
},
{
"channelType" : 3.0,
"gmtCreate" : "2018-09-03 10:00:00"
}
]
}
/* 2 */
{
"_id" : ObjectId("5b8e163df0fad825a708bc75"),
"userId" : 12323.0,
"appPlatform" : "ios",
"shortcutEntrance" : [
{
"entranceName" : "入口1",
"gmtCreate" : "2018-09-03 10:00:00"
},
{
"entranceName" : "入口2",
"gmtCreate" : "2018-09-03 10:00:00"
}
],
"classData" : [
{
"classId" : 123.0,
"position" : "left",
"gmtCreate" : "2018-09-03 10:00:00"
},
{
"classId" : 12356.0,
"position" : "right",
"gmtCreate" : "2018-09-03 10:00:00"
}
],
"channelVisit" : [
{
"channelType" : 2.0,
"gmtCreate" : "2018-09-03 10:00:00"
},
{
"channelType" : 3.0,
"gmtCreate" : "2018-09-03 10:00:00"
}
]
}
/* 3 */
{
"_id" : ObjectId("5b8e1642f0fad825a708bc76"),
"userId" : 12323.0,
"appPlatform" : "ios",
"shortcutEntrance" : [
{
"entranceName" : "入口1",
"gmtCreate" : "2018-09-03 10:00:00"
},
{
"entranceName" : "入口2",
"gmtCreate" : "2018-09-03 10:00:00"
}
],
"classData" : [
{
"classId" : 1234.0,
"position" : "left",
"gmtCreate" : "2018-09-03 10:00:00"
},
{
"classId" : 12356.0,
"position" : "right",
"gmtCreate" : "2018-09-03 10:00:00"
}
],
"channelVisit" : [
{
"channelType" : 2.0,
"gmtCreate" : "2018-09-03 10:00:00"
},
{
"channelType" : 3.0,
"gmtCreate" : "2018-09-03 10:00:00"
}
]
}
那么我需要统计classData.classId 相同的有多少。
解决方案
- 先对过滤出自己需要的数据
{"$project":{"classData.classId":1,"classData.position":1}}
获得得数据如下：
/* 1 */
{
"_id" : ObjectId("5b8c996e5f814eb3c37eb49b"),
"classData" : [
{
"classId" : 123.0,
"position" : "left"
},
{
"classId" : 12356.0,
"position" : "right"
}
]
}
/* 2 */
{
"_id" : ObjectId("5b8e163df0fad825a708bc75"),
"classData" : [
{
"classId" : 123.0,
"position" : "left"
},
{
"classId" : 12356.0,
"position" : "right"
}
]
}
/* 3 */
{
"_id" : ObjectId("5b8e1642f0fad825a708bc76"),
"classData" : [
{
"classId" : 1234.0,
"position" : "left"
},
{
"classId" : 12356.0,
"position" : "right"
}
]
}
_id 默认为1 也就是
{"$project":{"_id":1,"classData.classId":1,"classData.position":1}}
- 对classData数组进行分类切分
{"$unwind":"$classData"}
获取数据如下：
/* 1 */
{
"_id" : ObjectId("5b8c996e5f814eb3c37eb49b"),
"classData" : {
"classId" : 123.0,
"position" : "left"
}
}
/* 2 */
{
"_id" : ObjectId("5b8c996e5f814eb3c37eb49b"),
"classData" : {
"classId" : 12356.0,
"position" : "right"
}
}
/* 3 */
{
"_id" : ObjectId("5b8e163df0fad825a708bc75"),
"classData" : {
"classId" : 123.0,
"position" : "left"
}
}
/* 4 */
{
"_id" : ObjectId("5b8e163df0fad825a708bc75"),
"classData" : {
"classId" : 12356.0,
"position" : "right"
}
}
/* 5 */
{
"_id" : ObjectId("5b8e1642f0fad825a708bc76"),
"classData" : {
"classId" : 1234.0,
"position" : "left"
}
}
/* 6 */
{
"_id" : ObjectId("5b8e1642f0fad825a708bc76"),
"classData" : {
"classId" : 12356.0,
"position" : "right"
}
}
那么这样了就很好去获取classId得总数了
{"$group":{_id:"$classData.classId","classIdSum":{"$sum":1}}}
获取数据如下
/* 1 */
{
"_id" : 1234.0,
"classIdSum" : 1.0
}
/* 2 */
{
"_id" : 12356.0,
"classIdSum" : 3.0
}
/* 3 */
{
"_id" : 123.0,
"classIdSum" : 2.0
}
总命令如下：
db.getCollection('SHORTCUT_ENTRANCE_20180903').aggregate(
[
{"$project":{"classData.classId":1,"classData.position":1}},
{"$unwind":"$classData"},
{"$group":{_id:"$classData.classId","classIdSum":{"$sum":1}}}
])
数据统计存入业务表
结合Spring，使用mongoTemplate：
- 配置数据源
<!-- 数据源 -->
<mongo:db-factory id="mongoDbFactory" uri="mongodb://${mongo.database}:${mongo.password}@${mongo.host}:${mongo.port}/${mongo.username}?maxPoolSize=2000"/>
<bean id="mongoTemplate" class="org.springframework.data.mongodb.core.MongoTemplate">
<constructor-arg name="mongoDbFactory" ref="mongoDbFactory"/>
</bean>
- 从mongo获取统计数据存入业务表
核心代码如下：
Aggregation agg = Aggregation.newAggregation(
Aggregation.project("classData.classId","classData.position"),
Aggregation.unwind("$classData"),
Aggregation.group("$classData.classId").count().as("sim")
)
AggregationResults<BasicDBObject> objects = mongoTemplate.aggregate(agg,collection,BasicDBObject.class);//获取需要的统计数据
Iterator<BasicDBObject> iterator = objects.iterator();
while(iterator.hasNext()){
DBObject object = iterator.next();//获取统计数据中单个集合
........ //业务逻辑 存入业务表
}
