在我的mongoDB中北京共有16個區縣




其中只有密雲和延慶是縣，其他的為區，現在要將這兩個例外查出來

直接用mongoDB shell命令是這樣查詢的：

db.country.find({'name':{$regex:/縣/},'sheng':'11','level':3})

java實現如下：

package com.adtec.mongodb;

import java.util.Iterator;
import java.util.regex.Pattern;

import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import
 
 com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.MongoClient;

/**
 * 
 * @author 浪丶蕩 
 * <br>
 * 模糊查詢例項
 *
 */
public class BlurQuery {
    private String host = "192.168.71.193";

    private int port = 27017;

    public static void main(String[] args) {
        BlurQuery blurQuery = new
 
 BlurQuery();
        //資料庫test
        String dbname = "test";
        DB db = blurQuery.getDB(dbname);
        //集合country
        String collectionName = "country";
        //獲取結果集
        DBCursor cur = blurQuery.query(db, collectionName);
        //show一下結果
        blurQuery.printDBCursor(cur);


    }

    /**
     * 
     * @param
 
 dbname
     * @return 獲取一個與指定資料庫相關聯的DB物件
     */
    public DB getDB(String dbname) {

        @SuppressWarnings("resource")
        MongoClient mongoClient = new MongoClient(host, port);
        @SuppressWarnings("deprecation")
        DB db = mongoClient.getDB(dbname);
        return db;
    }

    /**
     * 
     * @param db
     * @param name
     * @return DBCursor
     * 查詢北京市縣級單位帶"縣"字的城市<br>
     * mongodb vue 是db.country.find({'name':{$regex:/縣/},'sheng':'11','level':3})
     */
    public DBCursor query(DB db, String collectionName) {
        DBCollection dbColl = db.getCollection(collectionName);

        // 模糊匹配正則規則（只要名字裡帶縣字）
        Pattern pattern = Pattern.compile("^.*縣.*$", Pattern.CASE_INSENSITIVE);
        BasicDBObject query = new BasicDBObject();
        //加入查詢條件
        query.put("name", pattern);
        query.put("sheng", "11");
        query.put("level", 3);
        //按名次升序排序
        BasicDBObject sort = new BasicDBObject();
        // 1,表示正序； －1,表示倒序
        sort.put("name", 1);
        DBCursor cur = dbColl.find(query).sort(sort);
        return cur;
    }

    /**
     *  遍歷結果集
     * @param cur
     */
    private void printDBCursor(DBCursor cur) {
        Iterator<DBObject> iterator = cur.iterator();
        while (iterator.hasNext()) {
            System.out.println(iterator.next());
        }
    }
}

結果：

十一月 21, 2017 3:12:16 下午 com.mongodb.diagnostics.logging.JULLogger log
資訊: Cluster created with settings {hosts=[192.168.71.193:27017], mode=SINGLE, requiredClusterType=UNKNOWN, serverSelectionTimeout='30000 ms', maxWaitQueueSize=500}
十一月 21, 2017 3:12:16 下午 com.mongodb.diagnostics.logging.JULLogger log
資訊: No server chosen by ReadPreferenceServerSelector{readPreference=primary} from cluster description ClusterDescription{type=UNKNOWN, connectionMode=SINGLE, serverDescriptions=[ServerDescription{address=192.168.71.193:27017, type=UNKNOWN, state=CONNECTING}]}. Waiting for 30000 ms before timing out
十一月 21, 2017 3:12:16 下午 com.mongodb.diagnostics.logging.JULLogger log
資訊: Opened connection [connectionId{localValue:1, serverValue:14}] to 192.168.71.193:27017
十一月 21, 2017 3:12:16 下午 com.mongodb.diagnostics.logging.JULLogger log
資訊: Monitor thread successfully connected to server with description ServerDescription{address=192.168.71.193:27017, type=STANDALONE, state=CONNECTED, ok=true, version=ServerVersion{versionList=[3, 4, 5]}, minWireVersion=0, maxWireVersion=5, maxDocumentSize=16777216, roundTripTimeNanos=1732855}
十一月 21, 2017 3:12:16 下午 com.mongodb.diagnostics.logging.JULLogger log
資訊: Opened connection [connectionId{localValue:2, serverValue:15}] to 192.168.71.193:27017
{ "_id" : { "$oid" : "59ec563f937ceb812c804c65"} , "code" : "110228" , "sheng" : "11" , "di" : "02" , "xian" : "28" , "name" : "密雲縣" , "level" : 3.0}
{ "_id" : { "$oid" : "59ec563f937ceb812c804c66"} , "code" : "110229" , "sheng" : "11" , "di" : "02" , "xian" : "29" , "name" : "延慶縣" , "level" : 3.0}