mongo学习-group操作以及java代码

原数据：

/* 1 */
{
    "_id" : ObjectId("552a330e05c27486b9b9b650"),
    "_class" : "com.mongo.model.Orders",
    "onumber" : "002",
    "date" : ISODate("2014-01-03T16:03:00.000Z"),
    "cname" : "zcy",
    "item" : {
        "quantity" : 1.0,
        "price" : 4.0,
        "pnumber" : "p002"
    }
}

/* 2 */
{
    "_id" : ObjectId("552a331d05c275d8590a550d"),
    "_class" : "com.mongo.model.Orders",
    "onumber" : "003",
    "date" : ISODate("2014-01-04T16:03:00.000Z"),
    "cname" : "zcy",
    "item" : {
        "quantity" : 10.0,
        "price" : 2.0,
        "pnumber" : "p001"
    }
}

/* 3 */
{
    "_id" : ObjectId("552a333105c2f28194045a72"),
    "_class" : "com.mongo.model.Orders",
    "onumber" : "003",
    "date" : ISODate("2014-01-04T16:04:00.000Z"),
    "cname" : "zcy",
    "item" : {
        "quantity" : 30.0,
        "price" : 4.0,
        "pnumber" : "p002"
    }
}

/* 4 */
{
    "_id" : ObjectId("552a333f05c2b62c01cff50e"),
    "_class" : "com.mongo.model.Orders",
    "onumber" : "004",
    "date" : ISODate("2014-01-05T16:03:00.000Z"),
    "cname" : "zcy",
    "item" : {
        "quantity" : 5.0,
        "price" : 4.0,
        "pnumber" : "p002"
    }
}

　　

一。mongo语句

db.orders.group({
    key:{date:1,"item.pnumber" : 1},
    initial:{"total":0},
    reduce:function Reduce(doc,out){
         out.total+=doc.item.price
        }
    })

　　

对out数据进一步处理

db.orders.group({
	key: {
		date: 1
	},
	initial: {
		"total": 0,
                "money":0
	},
	reduce: function Reduce(doc, out) {
		out.total += doc.item.quantity;
                out.money += doc.item.price*doc.item.quantity
	},
        finalize:function Finalize(out){
            out.avg=out.money/out.total
            return out

         }

})

　　

keyf ：对分组字段先进行处理然后分组

db.orders.group({
	keyf: function keysss(doc){
          return {"month":doc.date.getDay()+1}
        },
	initial: {
		"total": 0,
                "money":0
	},
	reduce: function Reduce(doc, out) {
		out.total += doc.item.quantity;
                out.money += doc.item.price*doc.item.quantity
	},
        finalize:function Finalize(out){
            out.avg=out.money/out.total
            return out
         }

})

　　

java代码：

@Test
    public void group(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("classpath:111.xml");
        MongoTemplate mongoTemplate= (MongoTemplate) applicationContext.getBean("mongoTemplate");
        GroupBy groupBy=new GroupBy("date");
        BasicDBObject basicDBObject=new BasicDBObject();
        basicDBObject.put("total",0);
        basicDBObject.put("money",0);
        groupBy.initialDocument(basicDBObject);
        groupBy.reduceFunction("function Reduce(doc, out) {out.total += doc.item.quantity;out.money += doc.item.price*doc.item.quantity}");
        groupBy.finalizeFunction("function Finalize(out){\n" +
                "            out.avg=out.money/out.total\n" +
                "            return out\n" +
                "         }");
//        groupBy.finalizeFunction("function Finalize(out) {out.avg = out.money / out.totalreturn out}");
        GroupByResults<Object> orders = mongoTemplate.group("orders", groupBy, Object.class);

    }