MongDB文档型数据库
1.吐槽和评论数据特点：
特点：
- 数据量大
- 写入频繁
- 价值较低
这样的数据更适合用MongoDb来存储
2.使用MongoDB命令行进行相关的增删改查操作
use spit
db.spit.insert({
content:"听说1024社区很给力",userid:"1011",nickname:"smallCuteMonkey",visits:NumberInt(902)})
db.spit.find()
db.spit.insert({
_id:"1",content:"听说1024社区很good",userid:"1011",nickname:"smallCuteMonkey",visits:NumberInt(902)})
db.spit.insert({
_id:"1",content:"听说1024社区很excellent",userid:"1011",nickname:"smallCuteMonkey",visits:NumberInt(902)})
db.spit.insert({
_id:"1",content:"听说1024社区很wonderful",userid:"1011",nickname:"smallCuteMonkey",visits:NumberInt(902)})
db.spit.insert({
_id:"2",content:"听说1024社区很great",userid:"1011",nickname:"smallCuteMonkey",visits:NumberInt(902)})
db.spit.find()
//可以根据条件进行查询，和限制查询的数量柘城
db.spit.find({
"userid":"1013"})
db.spit.find().limit(4)
//这两个更新的区别
db.spit.update({
"_id":"1"},{
"visits":NumberInt(1000)})
db.spit.update({
"_id":"2"},{
$set:{
"visits":NumberInt(1000)}})
db.spit.find()
db.spit.remove({
"_id":"1"})
db.spit.find()
db.spit.count()
db.spit.count({
"userid":"1011"})
//正则表达式 ^以...开头查$以...结尾进行查询 查询流量开头的数据信息
db.spit.find({
"content":/^流量/})
//查询以great结尾的数据
db.spit.find({
"content":/$great/})
db.spit.insert({
_id:"7",content:"流量没有了",userid:"1013",nickname:"smallCuteMonkey",visits:NumberInt(902)})
db.spit.insert({
_id:"6",content:"很great",userid:"1012",nickname:"smallCuteMonkey",visits:NumberInt(2000)})
//> < >= <=
db.spit.find({
"visits":{
$gt:1000}})
//区间查询 in nin
db.spit.find({
"userid":{
$in:["1013","1012"]}})
db.spit.find({
"userid":{
$nin:["1013","1012"]}})
//多个条件查询
db.spit.find({
$and:[{
"visits":{
$gt:1000}},{
"visits":{
$lte:2000}}]})
db.spit.find({
$and:[{
"userid":"1013"},{
"visits":{
$lt:2000}}]})
//让id为2的增加5
db.spit.update({
"_id":"2"},{
$inc:{
"visits":NumberInt(1)}})
db.spit.find()
use comment
show collections
db.comment.drop()
//进行插入的时候自动创建数据库
db.col.insert({
title: 'MongoDB 教程',
description: 'MongoDB 是一个 Nosql 数据库',
by: '菜鸟教程',
url: 'http://www.runoob.com',
tags: ['mongodb', 'database', 'NoSQL'],
likes: 100
})
show collections
//查询title为string类型的type
db.col.find({
"title":{
$type:"string"}})
//排序根据likes的 1 升序 -1 倒序 排序
db.col.find().sort({
"likes":1})
db.col.find().sort({
"likes":-1})
db.spit.find()
3.用java操作MongoDB进行相关的增删改查和特殊条件查询
使用Document（相当于一条数据）插入对象：
import com.mongodb.MongoClient;
import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
import org.bson.Document;
public class MongoDBInsert {
public static void main(String[] args) {
// 1.获取连接
MongoClient mongoClient=new MongoClient("127.0.0.1");
// 获取指定数据库
MongoDatabase spitdb = mongoClient.getDatabase("spit");
// 3.获取指定Collection 其实就是表连接对象
MongoCollection<Document> spit = spitdb.getCollection("spit");
Document document = new Document();
document.put("content","i am so brave,and handsomebody");
document.put("visits",10000);
document.put("nickname","smallCuteMonkey");
document.put("userid","10086");
spit.insertOne(document);
// 关闭连接
mongoClient.close();
}
}
使用BasicDBObject进行数据的相关的查询：
import com.mongodb.BasicDBObject;
import com.mongodb.MongoClient;
import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
import com.sun.javafx.scene.layout.region.BackgroundSizeConverter;
import jdk.nashorn.internal.ir.CallNode;
import org.bson.Document;
public class TestMongoDB {
public static void main(String[] args) {
// 1.获取连接
MongoClient mongoClient=new MongoClient("127.0.0.1");
// 获取指定数据库
MongoDatabase spitdb = mongoClient.getDatabase("spit");
// 3.获取指定Collection 其实就是表连接对象
MongoCollection<Document> spit = spitdb.getCollection("spit");
// 5. 构建相关的查询条件 BasicDBObject
// BasicDBObject bson=new BasicDBObject("userid","1013");
/*
查询测量大于1000的单个条件
BasicDBObject bson=new BasicDBObject("visits",new BasicDBObject("$gt",1000));
*/
// 查询两个条件的
BasicDBObject bson1=new BasicDBObject("visits",new BasicDBObject("$gt",900));
BasicDBObject bson2 = new BasicDBObject("visits", new BasicDBObject("$lt", 1000));
BasicDBObject[] bson=new BasicDBObject[2];
bson[0]=bson1;
bson[1]=bson2;
BasicDBObject andBson = new BasicDBObject("$and", bson);
// 4.执行相关的操作
// 一个document就相当于一条数据
FindIterable<Document> documents = spit.find(andBson);
for (Document docuemnt :
documents) {
System.out.println("获取内容"+docuemnt.getString("content"));
System.out.println("获取userid"+docuemnt.getString("userid"));
System.out.println("获取昵称"+docuemnt.getString("nickname"));
System.out.println("获取访问量"+docuemnt.getInteger("visits"));
System.out.println("--------------------");
}
// 关闭连接
mongoClient.close();
}
}