MongoDB第四天（操作文档，添加，更新，查询以及对于日期的相关操作）

Wesley13
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添加文档：

添加单个文档，多个文档

package com.bjsxt.mongodbdemo;

import com.mongodb.client.MongoCollection;
import org.bson.Document;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class InsertDocument {
    MongoCollection collection = MongoDBPoolAuthUtil.getCollection("develop", "devtest");
    public static void main(String[] args) {
        InsertDocument insert=new InsertDocument();
        //insert.insertSingleDocument();
        insert.insertManyDocument();
    }

    /**
     * 添加单个文档
     */
    public void insertSingleDocument(){
        Document document=new Document();
        document.append("uname","lisi").append("age",25).append("userdesc","good").append("hobby", Arrays.asList(new String[]{"Music","Movie"}));
        collection.insertOne(document);
    }

    /**
     * 添加多个文档
     */
    public void insertManyDocument(){
        List<Document> documentList=new ArrayList<>();
        for (int i=1;i<5;i++){
            Document document=new Document();
            document.append("uname","zs"+i);
            document.append("age",25+i);
            document.append("userdesc","prefect");
            document.append("hobby", Arrays.asList(new String[]{"美女","Ballgame"}));
            documentList.add(document);
        }
        collection.insertMany(documentList);
    }
}

更新文档：

更新单个文档单个键，更新单个文档多个键，更新多个文档单个键，更新多个文档多个键，更新数组

package com.bjsxt.mongodbdemo;

import com.mongodb.client.MongoCollection;
import com.mongodb.client.model.Filters;
import org.bson.Document;

public class UpdateDocument {
    MongoCollection collection = MongoDBPoolAuthUtil.getCollection("develop", "devtest");

    public static void main(String[] args) {
        UpdateDocument update=new UpdateDocument();
        //update.updateManyKeyDocument();
        //update.updateManyDocumentSingleKey();
        //update.updateManyDocumentManyKey();
       // update.updateSingleDocumentArray();
        update.updateManyDocumentArray();
    }

    /**
     * 更新单个文档单个键
     */
    public void updateSingleKeyDocument(){
        collection.updateOne(Filters.eq("uname","lisi"),new Document("$set",new Document("age",28)));
    }

    /**
     * 更新单个文档多个键
     */
    public void updateManyKeyDocument(){
        collection.updateOne(Filters.eq("uname","zs1"),new Document("$set",new Document("age",18).append("userdesc","very good")));
    }

    /**
     * 更新多个文档单个键
     */
    public void updateManyDocumentSingleKey(){
        collection.updateMany(Filters.ne("uname",null),new Document("$set",new Document("userdesc","pretry good")));
    }

    /**
     * 更新多个文档多个键
     */
    public void updateManyDocumentManyKey(){
        collection.updateMany(Filters.ne("uname",null),new Document("$set",new Document("userdesc","good").append("age",18)));
    }

    /**
     * 更新单个文档的数组
     */
    public void updateSingleDocumentArray(){
        collection.updateMany(Filters.eq("uname","zs2"),new Document("$push",new Document("hobby","看小电影")));
    }

    /**
     * 更新单个文档的多个数组
     */
    public void updateManyDocumentArray(){
        collection.updateMany(Filters.ne("uname",null),new Document("$push",new Document("hobby","欣赏小电影")));
    }
}

查询文档:

查询全部文档，查询指定文档，查询多个文档（操作符）

package com.bjsxt.mongodbdemo;

import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.model.Filters;
import org.bson.Document;
import org.bson.types.ObjectId;

import java.util.regex.Pattern;

public class SelectDocument {
    MongoCollection collection = MongoDBPoolAuthUtil.getCollection("develop", "devtest");

    public static void main(String[] args) {
        SelectDocument select=new SelectDocument();
        //select.selectAll();
        //select.selectById();
        //select.selectManytype();
        /*select.selectManyin();*/
        //select.selectManynin();
        //select.selectManyregex();
        //select.selectManyand();
        //select.selectManyor();
        //select.selectManyorand();
        select.selectManysort();
    }

    /**
     * 查询所有
     */
    public void selectAll(){
        FindIterable<Document> iterable = collection.find();
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()){
            Document doc = iterator.next();
            System.out.println(doc.get("uname")+"\t"+doc.get("age")+"\t"+doc.get("userdesc")+"\t"+doc.get("hobby"));
        }
    }

    /**
     * 根据id查询
     */
    public void selectById(){
        FindIterable<Document> iterable = collection.find(Filters.eq("_id",new ObjectId("5dc0d6ca614f6b0a0c1915e3")));
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()){
            Document doc = iterator.next();
            System.out.println(doc.get("uname")+"\t"+doc.get("age")+"\t"+doc.get("userdesc")+"\t"+doc.get("hobby"));
        }
    }

    /**
     * 查询多个文档+gt
     */
    public void selectManygt(){
        FindIterable<Document> iterable = collection.find(Filters.gt("age",17));
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()){
            Document doc = iterator.next();
            System.out.println(doc.get("uname")+"\t"+doc.get("age")+"\t"+doc.get("userdesc")+"\t"+doc.get("hobby"));
        }
    }

    /**
     * 查询多个文档+type
     */
    public void selectManytype(){
        FindIterable<Document> iterable = collection.find(Filters.type("age","number"));
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()){
            Document doc = iterator.next();
            System.out.println(doc.get("uname")+"\t"+doc.get("age")+"\t"+doc.get("userdesc")+"\t"+doc.get("hobby"));
        }
    }

    /**
     * 查询多个文档+in
     */
    public void selectManyin(){
        FindIterable<Document> iterable = collection.find(Filters.in("uname","zs1","zs2","zs3"));
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()){
            Document doc = iterator.next();
            System.out.println(doc.get("uname")+"\t"+doc.get("age")+"\t"+doc.get("userdesc")+"\t"+doc.get("hobby"));
        }
    }

    /**
     * 查询多个文档+nin
     */
    public void selectManynin(){
        FindIterable<Document> iterable = collection.find(Filters.nin("uname","zs1","zs2","zs3"));
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()){
            Document doc = iterator.next();
            System.out.println(doc.get("uname")+"\t"+doc.get("age")+"\t"+doc.get("userdesc")+"\t"+doc.get("hobby"));
        }
    }

    /**
     * 查询多个文档以z开头2结尾
     */
    public void selectManyregex(){
        FindIterable<Document> iterable = collection.find(Filters.regex("uname", Pattern.compile("^z.*2$")));
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()){
            Document doc = iterator.next();
            System.out.println(doc.get("uname")+"\t"+doc.get("age")+"\t"+doc.get("userdesc")+"\t"+doc.get("hobby"));
        }
    }

    /**
     * 查询多个文档姓名是zs1，年龄是18
     */
    public void selectManyand(){
        FindIterable<Document> iterable = collection.find(Filters.and(Filters.eq("uname","zs1"),Filters.eq("age",18)));
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()){
            Document doc = iterator.next();
            System.out.println(doc.get("uname")+"\t"+doc.get("age")+"\t"+doc.get("userdesc")+"\t"+doc.get("hobby"));
        }
    }

    /**
     *  查询用户要求 uname 是 zs1，或者 age 是 18
     */
    public void selectManyor(){
        FindIterable<Document> iterable = collection.find(Filters.or(Filters.eq("uname","zs1"),Filters.eq("age",18)));
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()){
            Document doc = iterator.next();
            System.out.println(doc.get("uname")+"\t"+doc.get("age")+"\t"+doc.get("userdesc")+"\t"+doc.get("hobby"));
        }
    }

    /**
     * 查询文档中 uname 为 lisi 并且年龄为 18 岁，或者 userdesc 为 good
     */
    public void selectManyorand(){
        FindIterable<Document> iterable = collection.find(Filters.or(Filters.and(Filters.eq("uname","lisi"),Filters.eq("age",18)),Filters.eq("userdesc","good")));
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()){
            Document doc = iterator.next();
            System.out.println(doc.get("uname")+"\t"+doc.get("age")+"\t"+doc.get("userdesc")+"\t"+doc.get("hobby"));
        }
    }

    /**
     * 查询文档中 username 是 z 开头的，根据 username 对结果做降序排序。1升序排序， -1 降序排序规则 $sort:{username,-1}
     */
    public void selectManysort(){
        FindIterable<Document> iterable = collection.find(Filters.regex("uname",Pattern.compile("^z"))).sort(new Document("uname",-1));
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()){
            Document doc = iterator.next();
            System.out.println(doc.get("uname")+"\t"+doc.get("age")+"\t"+doc.get("userdesc")+"\t"+doc.get("hobby"));
        }
    }
}

对于时间的操作

插入主机时间，插入指定时间，根据指定日期去查询数据（操作符：gt,eq，）

package com.bjsxt.mongodbdemo;

import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.model.Filters;
import org.bson.Document;

import java.util.Date;

public class DateOperation {
    MongoCollection collection = MongoDBPoolAuthUtil.getCollection("develop", "devtest");

    public static void main(String[] args) {
            DateOperation operation=new DateOperation();
            //operation.insertDate();
            //operation.insertCusDate();
            //operation.SelectDate();
            operation.SelectDategt();
    }

    /**
     * 插入时间
     */
    public void insertDate(){
        Document doc=new Document();
        doc.put("uname","ww");
        doc.put("age",25);
        doc.put("userdesc","very good");
        doc.put("birth",new Date());
        collection.insertOne(doc);
    }

    /**
     * 插入指定日期
     */
    public void insertCusDate(){
        Date date=DateUtil.stringToDate("yyyy-MM-dd HH:mm:ss","2019-05-01 13:32:13");
        Document doc=new Document();
        doc.put("uname","zl");
        doc.put("age",28);
        doc.put("userdesc","very very good");
        doc.put("birth",date);
        collection.insertOne(doc);
    }

    /**
     * 根据指定日期去查询数据
     */
    public void SelectDate(){
        Date date=DateUtil.stringToDate("yyyy-MM-dd hh:mm:ss","2019-05-01 13:32:13");
        FindIterable iterable = collection.find(Filters.eq("birth", date));
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()){
            Document doc = iterator.next();
            String birth = DateUtil.dateToString("yyyy-MM-dd hh:mm:ss", (Date) doc.get("birth"));
            System.out.println(doc.get("uname")+"\t"+doc.get("age")+"\t"+doc.get("userdesc")+"\t"+birth);
        }
    }

    /**
     * 根据指定日期去查询数据
     */
    public void SelectDategt(){
        Date date=DateUtil.stringToDate("yyyy-MM-dd hh:mm:ss","2019-01-01 00:00:00");
        FindIterable iterable = collection.find(Filters.gt("birth", date));
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()){
            Document doc = iterator.next();
            String birth = DateUtil.dateToString("yyyy-MM-dd hh:mm:ss", (Date) doc.get("birth"));
            System.out.println(doc.get("uname")+"\t"+doc.get("age")+"\t"+doc.get("userdesc")+"\t"+birth);
        }
    }
}

聚合操作（各种查询，操作符）

package com.bjsxt.mongodbdemo;

import com.mongodb.client.AggregateIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import org.bson.Document;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class AggregateOperation {
    MongoCollection collection = MongoDBPoolAuthUtil.getCollection("develop", "devtest");

    public static void main(String[] args) {
        AggregateOperation operation = new AggregateOperation();
        //operation.selectDocumentAggregateCount();
        //operation.selectDocumentAggregateSum();
        //operation.selectDocumentAggregateGroupBySum();
        //operation.selectDocumentAggregateGroupByWhere();
        //operation.selectDocumentAggregateGroupByHaving();
        //operation.selectDocumentProject();
        //operation.selectDocumentProjectConcat();
        //operation.selectDocumentProjectAdd();
        operation.selectDocumentProjectDate();
    }

    /**
     * 查询集合中的文档数量
     * MongoShell:db.dev.aggregate([{$group:{_id:null,count:{$sum:1}}
     */
    public void selectDocumentAggregateCount() {
        Document doc = new Document();
        doc.put("$sum", 1);

        Document count = new Document();
        count.put("_id", null);
        count.put("count", doc);

        Document group = new Document();
        group.put("$group", count);

        List<Document> list = new ArrayList<>();
        list.add(group);
        AggregateIterable iterable = collection.aggregate(list);
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()) {
            Document docu = iterator.next();
            System.out.println(docu.get("count"));
        }
    }

    /**
     * 需求：查询集合中所有 age 键中的值的总和
     * MongoShell:db.dev.aggregate([{$group:{_id:null,totalSize:{$sum:"$size"}}}])
     */
    public void selectDocumentAggregateSum() {
        Document document = new Document();
        document.put("$sum", "$age");

        Document sumage = new Document();
        sumage.put("_id", null);
        sumage.put("sumage", document);

        Document group = new Document();
        group.put("$group", sumage);
        List<Document> list = new ArrayList<>();
        list.add(group);

        AggregateIterable iterable = collection.aggregate(list);
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()) {
            Document doc = iterator.next();
            System.out.println("sum_age: " + doc.get("sumage"));
        }
    }

    /**
     * 需求：对 uname 进行分组，计算每组中的 age 的总和
     * MongoShell:db.dev.aggregate([{$group:{_id:"$title",totalSize:{$sum:"$size"}}}])
     */
    public void selectDocumentAggregateGroupBySum() {
        Document document = new Document();
        document.put("$sum", "$age");

        Document sumage = new Document();
        sumage.put("_id", "$uname");
        sumage.put("sumage", document);

        Document group = new Document();
        group.put("$group", sumage);
        List<Document> list = new ArrayList<>();
        list.add(group);

        AggregateIterable iterable = collection.aggregate(list);
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()) {
            Document doc = iterator.next();
            System.out.println(doc.get("_id") + "\t" + doc.get("sumage"));
        }
    }

    /**
     * 需求：查询 devtest 集合有多少文档的 age 大于 20。
     * Mongo Shell：db.dev.aggregate([{$match:{size:{$gt:200}}},{$group:{_id:null,totalSize:{$sum:1}}}])
     */
    public void selectDocumentAggregateGroupByWhere() {
        Document match = new Document();
        match.put("$match", new Document("age", new Document("$gt", 20)));

        Document sumage = new Document();
        sumage.put("$sum", 1);

        Document two = new Document();
        two.put("_id", null);
        two.put("sumage", sumage);

        Document group = new Document();
        group.put("$group", two);
        List<Document> list = new ArrayList<>();
        list.add(match);
        list.add(group);
        AggregateIterable iterable = collection.aggregate(list);
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()) {
            Document doc = iterator.next();
            System.out.println(doc.get("sumage"));
        }
    }

    /**
     * 需求：查询 devtest 集合，根据 uname 分组计算出每组的 age 的总和，并过滤掉总和小于 20 的文档。
     * Mongo Shell：db.dev.aggregate([{$group:{_id:"$title",totalSize:{$sum:"$size"}}},{$match:{totalSize:{$gt:200}}}])
     */
    public void selectDocumentAggregateGroupByHaving() {
        Document match = new Document();
        match.put("$match", new Document("sumage", new Document("$gt", 20)));

        Document sumage = new Document();
        sumage.put("$sum", "$age");

        Document two = new Document();
        two.put("_id", "$uname");
        two.put("sumage", sumage);

        Document group = new Document();
        group.put("$group", two);
        List<Document> list = new ArrayList<>();
        list.add(group);
        list.add(match);

        AggregateIterable iterable = collection.aggregate(list);
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()) {
            Document doc = iterator.next();
            System.out.println(doc.get("_id")+"\t"+doc.get("sumage"));
        }
    }

    /**
     * 需求：查询 devtest 集合，将数组中的内容拆分显示，并只显示 uname 键与 hobby键的值。
     * Mongo Shell：db.dev.aggregate([{$unwind:"$tags"},{$project:{_id:0,tags:"$tags",title:"$title"}}])
     */
    public void selectDocumentProject(){
        Document unwind=new Document();
        unwind.put("$unwind","$hobby");

        Document show=new Document();
        show.put("_id",0);
        show.put("hobby","$hobby");
        show.put("uname","$uname");

        Document project=new Document();
        project.put("$project",show);

        List<Document> list=new ArrayList<>();
        list.add(unwind);
        list.add(project);


        AggregateIterable iterable = collection.aggregate(list);
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()) {
            Document doc = iterator.next();
            System.out.println(doc);
        }

    }


    /**
     * 需求：查询 devtest 集合，将数组中的内容拆分显示。将 uname 字段和 hobby字段的值拼接为一个完整字符串并在 uname_hooby 字段中显示。
     * Mongo Shell：db.dev.aggregate([{$unwind:"$tags"},{$project:{_id:0,Title_Tags:{$concat:["$title","-","$tags"]}}}])
     */
    public void selectDocumentProjectConcat(){
        Document unwind=new Document();
        unwind.put("$unwind","$hobby");

        Document concat=new Document();
        concat.put("$concat", Arrays.asList(new String[]{"$uname","_","$hobby"}));

        Document nh=new Document();
        nh.put("_id",0);
        nh.put("uname_hooby",concat);

        Document project=new Document();
        project.put("$project",nh);
        List<Document> list=new ArrayList<>();
        list.add(unwind);
        list.add(project);


        AggregateIterable iterable = collection.aggregate(list);
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()) {
            Document doc = iterator.next();
            System.out.println(doc);
        }
    }


    /**
     * 需求：查询 devtest 集合中数据，显示 uname 和 age 字段，为 age 字段数据做加 1 操作，显示字段命名为 age。排除那些没有 age 键的文档。
     * Mongo Shell：db.dev.aggregate([{$match:{size:{$ne:null}}},{$project:{_id:0,title:1,New_Size:{$add:["$size",1]}}}])
     */
    public void selectDocumentProjectAdd(){
        Document ne =new Document();
        ne.put("$ne",null);

        Document age=new Document();
        age.put("age",ne);

        Document match=new Document();
        match.put("$match",age);

        Document add=new Document();
        add.put("$add",Arrays.asList(new Object[]{"$age",1}));

        Document show =new Document();
        show.put("_id",0);
        show.put("uname",1);
        show.put("age",add);

        Document project =new Document();
        project.put("$project",show);
        List<Document> list=new ArrayList<>();
        list.add(match);
        list.add(project);


        AggregateIterable iterable = collection.aggregate(list);
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()) {
            Document doc = iterator.next();
            System.out.println(doc);
        }

    }

    /**
     * 需求：查询 devtest 集合查询那些有生日的用户，并按照 YYYY 年 mm 月dd 日 HH:MM:SS 格式显示日期。
     * 注意：如果直接在 MongoDB 中做日期的格式化处理，那么是按照表示 UTC时间来处理的，会少 8 个小时。建议在程序中
     * 通过 java.util.Date 来做日期的转换。
     * Mongo Shell：db.devtest.aggregate([{$match:{userbirth:{$ne:null}}},{$project:{自定义日期格式:{$dateToString:{format:"%Y 年%m 月%d日 %H:%M:%S",date:"$userbirth"}}}}])
     */
    public void selectDocumentProjectDate(){
        Document ne =new Document();
        ne.put("$ne",null);

        Document birth=new Document();
        birth.put("birth",ne);

        Document match=new Document();
        match.put("$match",birth);

       //{$project:{自定义日期格式:{$dateToString:{format:"%Y 年%m 月%d日 %H:%M:%S",date:"$userbirth"}}}}
        Document format=new Document();
        format.put("format","%Y 年%m 月%d日 %H:%M:%S");
        format.put("date","$birth");

        Document dateToString=new Document();
        dateToString.put("$dateToString",format);

        Document zdy=new Document();
        zdy.put("自定义日期格式",dateToString);

        Document project=new Document();
        project.put("$project",zdy);
        List<Document> list=new ArrayList<>();
        list.add(match);
        list.add(project);


        AggregateIterable iterable = collection.aggregate(list);
        MongoCursor<Document> iterator = iterable.iterator();
        while (iterator.hasNext()) {
            Document doc = iterator.next();
            System.out.println(doc);
        }

    }

}

日期的转化工具类

package com.bjsxt.mongodbdemo;

import java.text.SimpleDateFormat;
import java.util.Date;

public class DateUtil {
    /**
     * date to string
     */
    public static String dateToString(String pattern, Date date){
        SimpleDateFormat spdf=new SimpleDateFormat(pattern);
        String format = spdf.format(date);
        return format;
    }

    /**
     * String to date
     */
    public static Date stringToDate(String pattern, String date){
        SimpleDateFormat spdf=new SimpleDateFormat(pattern);
        try {
            Date parse = spdf.parse(date);
            return parse;
        }catch (Exception e){
            e.printStackTrace();
        }
        return null;
    }
}

俩种分页操作

package com.bjsxt.mongodbdemo;

import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import org.bson.Document;
import org.bson.types.ObjectId;

public class SelectDocumentByPage {
    MongoCollection collection = MongoDBPoolAuthUtil.getCollection("develop", "devtest");

    public static void main(String[] args) {
        SelectDocumentByPage docd=new SelectDocumentByPage();
        //docd.selectDocumentByPageUseSkipAndLimit(3);
        docd.selectDocumentByPageUseCondition(2,2,"5dc0d85c614f6b2730c1d0fd");
    }

    /**
     * 实现分页查询
     */
    public void selectDocumentByPageUseSkipAndLimit(int pageIndex){
        int page=(pageIndex-1)*2;
        Document doc=new Document("age",new Document("$ne",null));
        long count = collection.countDocuments(doc);
        System.out.println(count);
        FindIterable ite = collection.find(doc).limit(2).skip(page);
        MongoCursor<Document> iterator = ite.iterator();
        while (iterator.hasNext()){
            Document docu = iterator.next();
            System.out.println(docu);
        }
    }

    /**
     * 条件判断实现分页
     */
    public void selectDocumentByPageUseCondition(int pageIndex,int pageSize,String lastId){
        Document doc=new Document("age",new Document("$ne",null));
        long count = collection.countDocuments(doc);
        System.out.println(count);
        FindIterable ite =null;
        if (pageIndex==1){
            ite = collection.find(doc).limit(pageSize);
        }else {
            if (lastId!=null){
                doc.append("_id",new Document("$gt",new ObjectId(lastId)));
                ite = collection.find(doc).limit(pageSize);
            }
        }
        MongoCursor<Document> iterator = ite.iterator();
        while (iterator.hasNext()){
            Document docu = iterator.next();
            System.out.println(docu);
        }

    }
}
mongodbdateiteratorGolangGolang
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