一，问题描述

数据格式： id, timeStamp,count

条件1：查询 某个时间段 内的数据： timeStamp BETWEEN startTime AND endTime。比如 timeStamp BETWEEN 1499875200  AND 1499875600

条件2：记录 的 id 字段 属于某集合： id IN (1001,1002,1003)

条件3：记录 的count字段 大于某个阈值，比如： count > 10000

 

二，代码实现

条件1实现如下， $gte （greater equal）表示“大于等于 ”。【$lte（lower equal）】表示“小于等于”

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

 

条件2的实现如下，使用 $in ArrayList<Integer> 来表示 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;
    }

 

组合条件1 和 条件2 查询：（条件1 AND 条件2）.List 将所有 AND 组合的条件add进去，然后使用 $and 组合。

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

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

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

 

条件3：记录 的count字段 大于某个阈值，比如： count > 10000

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

 

WINDOWS下安装好MongoDB后，MongoDB采用Clietn--Server 模式。WIN10下启动MongoDB服务端：-dbpath 指定 数据存储目录(可自己指定一个)

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

 

另起一个 Cmd命令行，输入：

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

就可以以Shell方式操作MongoDB了。

mongodb 多个if判断 mongo 多条件查询_字段

输入 exit 退出

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

另外，推荐一个MongoDB的可视化工具：RoboMongoDB。执行相应的查询语句如下：

mongodb 多个if判断 mongo 多条件查询_List_02

 

 

三，新版本MongoDB(3.0版本以上)，使用Filters来组合多个条件

查询 timeStamp 在[startTimeStamp, endTimeStamp) 内的所有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方法连接了两个条件，其实还可以连接多个条件：比如查询 timeStamp 在[startTimeStamp, endTimeStamp) 区间内，并且 uid 在List<Long>uids 内的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还组合了 IN 条件：比如，查询 uid 在[123, 456, 789]中，可用如下条件：

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

 具体更多的条件查询，可查看Filters的源代码。关于Filters的更多的用法可参考：Filters的若干使用示例

 

四，MongoDB查询时，过滤某些字段

使用Document对象来指定需要查询或者排除的字段。0 表示不返回该字段的值，1 表示返回该字段的值。

1     //0 表示 不返回 该字段, 1 表示 返回该字段
2     private static Document fetchFields() {
3         Document fetchFields = new Document();
4         fetchFields.put("_id", 0);//查询的结果 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     }

然后再将 fetchFields 对象传入 project()方法即可，如下：

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

 

整个完整示例参考：

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 不抽取该字段, 1 表示 抽取该字段
    private static Document fetchFields() {
        Document fetchFields = new Document();
        fetchFields.put("_id", 0);//查询的结果 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);
        }
    }
}

 

 

五：参考文献

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

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