MongoDB 組合多個條件查詢($and、$in、$gte、$lte)


一,問題描述

數據格式: id, timeStamp,count

條件1:查詢 某個時間段 內的數據: timeStamp BETWEEN startTime AND endTime。比如 timeStamp BETWEEN 1499875200  AND 1499875600

條件2:記錄 的 id 字段 屬於某集合: id IN (1001,1002,1003)

條件3:記錄 的count字段 大於某個閾值,比如: count > 10000

 

二,代碼實現

條件1實現如下, $gte (greater equal)表示“大於等於 ”。【$lte(lower equal)】表示“小於等於”

    private DBObject timeCondi(long startTimeStamp, long endTimeStamp){
        DBObject queryCondition = new BasicDBObject("$gte", startTimeStamp).append("$lte", endTimeStamp);
        BasicDBObject query = new BasicDBObject("timeStamp", queryCondition);
        return query;
    }

 

條件2的實現如下,使用 $in ArrayList<Integer> 來表示 id IN (1001,1002,1003)

    private DBObject inCondi() {
        List<Integer> idList = new ArrayList<Integer>();
        idList.add(1001);
        idList.add(1002);
        idList.add(1003);

        BasicDBObject inQuery = new BasicDBObject();
        inQuery.put("id", new BasicDBObject("$in", idList));
        return inQuery;
    }

 

組合條件1 和 條件2 查詢:(條件1 AND 條件2).List 將所有 AND 組合的條件add進去,然后使用 $and 組合。

    private DBObject andQuery(long startTimeStamp, long endTimeStamp) {
        DBObject timeCondi = timeCondi(startTimeStamp, endTimeStamp);
        DBObject inCondi = inCondi();

        List<DBObject> andCondi = new ArrayList<DBObject>();
        andCondi.add(timeCondi);//組合 條件1
        andCondi.add(inCondi);//組合 條件2

        BasicDBObject andQuery = new BasicDBObject();
        andQuery.put("$and", andCondi);
        return andQuery;
    }

 

條件3:記錄 的count字段 大於某個閾值,比如: count > 10000

    private DBObject countCondi(int size) {
        DBObject queryCondition = new BasicDBObject("$gte", size);
        BasicDBObject query = new BasicDBObject("count", queryCondition);
        return query;
    }

 

WINDOWS下安裝好MongoDB后,MongoDB采用Clietn--Server 模式。WIN10下啟動MongoDB服務端:-dbpath 指定 數據存儲目錄(可自己指定一個)

D:\Program Files\MongoDB\Server\3.4\bin>.\mongod.exe -dbpath ..\data

 

另起一個 Cmd命令行,輸入:

D:\Program Files\MongoDB\Server\3.4\bin>.\mongo.exe

就可以以Shell方式操作MongoDB了。

輸入 exit 退出

D:\Program Files\MongoDB\Server\3.4\bin>netstat -ano | findstr 27017  查看端口是否開啟

另外,推薦一個MongoDB的可視化工具:RoboMongoDB。執行相應的查詢語句如下:

 

 

三,新版本MongoDB(3.0版本以上),使用Filters來組合多個條件

查詢 timeStamp 在[startTimeStamp, endTimeStamp) 內的所有document

1     private static Bson timeBetweenCondition(long startTimeStamp, long endTimeStamp) {
2         Bson condition = Filters.and(Filters.gte("timeStamp", startTimeStamp), Filters.lt("timeStamp", endTimeStamp));
3         return condition;
4     }

 

上面的示例,使用Filters的and方法連接了兩個條件,其實還可以連接多個條件:比如查詢 timeStamp 在[startTimeStamp, endTimeStamp) 區間內,並且 uid 在List<Long>uids 內的document

1     private static Bson multipleAndCondition(long startTimeStamp, long endTimeStamp, List<Long> uids) {
2         Bson condition = Filters.and(Filters.gte("timeStamp", startTimeStamp), Filters.lt("timeStamp", endTimeStamp), Filters.in("uid", uids));
3         return condition;
4     }

 

Filters還組合了 IN 條件:比如,查詢 uid 在[123, 456, 789]中,可用如下條件:

1     private static Bson uidInCondition(List<Long> uids) {
2         Bson condition = Filters.in("uid", uids);
3         return condition;
4     }

 具體更多的條件查詢,可查看Filters的源代碼。關於Filters的更多的用法可參考:Filters的若干使用示例

 

四,MongoDB查詢時,過濾某些字段

使用Document對象來指定需要查詢或者排除的字段。0 表示不返回該字段的值,1 表示返回該字段的值。

1     //0 表示 不返回 該字段, 1 表示 返回該字段
2     private static Document fetchFields() {
3         Document fetchFields = new Document();
4         fetchFields.put("_id", 0);//查詢的結果 不返回 _id 字段
5         fetchFields.put("uid", 1);//返回 uid 字段
6         fetchFields.put("chat", 1);//返回 chat 字段
7         return fetchFields;
8     }

然后再將 fetchFields 對象傳入 project()方法即可,如下:

collection.find(timeBetweenCondition(startTimeStamp, endTimeStamp)).projection(fetchFields())

 

整個完整示例參考:

import com.mongodb.MongoClient;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.MongoDatabase;
import com.mongodb.client.model.Filters;
import org.bson.Document;
import org.bson.conversions.Bson;

import java.time.LocalDateTime;
import java.time.ZoneId;
import java.util.Arrays;
import java.util.List;
//import static com.mongodb.client.model.Filters.*;

/**
 * Created by Administrator on 2017/10/20.
 */
public class MongoUtil {
    private static final String HOST = "localhost";
    private static final int PORT = 27017;
    private static final String DB_NAME = "test";
    private static final MongoClient mongoClient = new MongoClient(HOST, PORT);
    private static MongoDatabase getDataBase() {
        return mongoClient.getDatabase(DB_NAME);
    }

    private static MongoCollection<Document> getCollection(String collName) {
        return getDataBase().getCollection(collName);
    }

    private static Bson timeBetweenCondition(long startTimeStamp, long endTimeStamp) {
        Bson condition = Filters.and(Filters.gte("timeStamp", startTimeStamp), Filters.lt("timeStamp", endTimeStamp));
        return condition;
    }

    private static Bson uidInCondition(List<Long> uids) {
        Bson condition = Filters.in("uid", uids);
        return condition;
    }

    private static Bson multipleAndCondition(long startTimeStamp, long endTimeStamp, List<Long> uids) {
        Bson condition = Filters.and(Filters.gte("timeStamp", startTimeStamp), Filters.lt("timeStamp", endTimeStamp), Filters.in("uid", uids));
        return condition;
    }


    //0 表示 不抽取該字段, 1 表示 抽取該字段
    private static Document fetchFields() {
        Document fetchFields = new Document();
        fetchFields.put("_id", 0);//查詢的結果 不返回 _id 字段
        fetchFields.put("uid", 1);//返回 uid 字段
        fetchFields.put("chat", 1);//返回 chat 字段
        return fetchFields;
    }

    public static void main(String[] args) {
        MongoCollection collection = getCollection("mycollection_name");
        LocalDateTime today = LocalDateTime.of(2017, 8, 29, 0, 0, 0);
        LocalDateTime tomorrow = today.plusDays(1);

        long startTimeStamp = today.atZone(ZoneId.systemDefault()).toEpochSecond();
        long endTimeStamp = tomorrow.atZone(ZoneId.systemDefault()).toEpochSecond();
        Bson andCondition = multipleAndCondition(startTimeStamp, endTimeStamp, Arrays.asList(65496L));

//        Bson andCondition = timeBetweenCondition(startTimeStamp, endTimeStamp);
        Document fetchFields = fetchFields();
        MongoCursor<Document> cursor = collection.find(andCondition).projection(fetchFields).iterator(); long count = collection.count(andCondition);
        System.out.println(count);
        while (cursor.hasNext()) {
            Document document = cursor.next();
            String chat = (String) document.get("chat");
            Long uid = (Long) document.get("uid");
            System.out.println("chat:" + chat + ", uid:" + uid);
        }
    }
}

 

 

五:參考文獻

https://www.mkyong.com/mongodb/java-mongodb-query-document/

http://farenda.com/mongodb/mongodb-filtering-sorting-and-projections/

 

原文:http://www.cnblogs.com/hapjin/p/7450309.html


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