基础语法
插入
插入单条
// 插入一条数据到 "Books" 集合
db.Books.insertOne({title: "如何使用MongoDB",author: "IT小辉同学",year: 2023
})
插入多条数据
// 插入十条数据到 "Books" 集合
db.Books.insertMany([{ title: "平凡的世界", author: "路遥", year: 1986 },{ title: "呐喊", author: "鲁迅", year: 1923 },{ title: "朝花夕拾", author: "鲁迅", year: 1928 },{ title: "李自成", author: "王安忆", year: 2010 },{ title: "寻找安详", author: "郭文斌", year: 2000 },{ title: "推拿", author: "毕飞宇", year: 1999 },{ title: "苏东坡传", author: "林语堂", year: 2015 },{ title: "长安的荔枝", author: "马伯庸", year: 2021 },{ title: "林清玄散文集", author: "林清玄", year: 1988 },{ title: "橘颂", author: "张炜", year: 2022 }
])
查询
//查询全部
db.Books.find()//条件查询
db.Books.find({author:"鲁迅"})//模糊查询 /xxx/ 相当于like %xxx%
db.Books.find({author:{$regex:/同学/}})// 字段显示 1:显示, 0 不显示
db.Books.find({}, { title: 1, author: 1, _id: 0 })//排序
//正序:
db.Books.find().sort({year:1})
// 倒叙
db.Books.find().sort({year:-1})// 限制条数
db.Books.find().limit(3)
修改
//查询第一个条件的数据,然后进行修改
db.Books.updateOne({ title: "橘颂", author: "张炜", year: 2022 },{ $set: { year: 2023 } }
)//修改多条
db.Books.updateMany({ title: "橘颂", author: "张炜", year: 1111 },{ $set: { year: 2222 } }
)
删除
//单纯单条
db.Books.deleteOne({ title: "橘颂", author: "张炜", year: 2222 }
)//删除多条
db.Books.deleteMany({ title: "橘颂"})
场景
Springboot整合
服务引入
1、引入依赖
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-mongodb</artifactId>
</dependency><dependency><groupId>com.h2database</groupId><artifactId>h2</artifactId><scope>runtime</scope>
</dependency>
2、application.yaml配置
spring:data:mongodb:host: 127.0.0.1port: 27017# 如果有密码的,则需要配置密码
# username: "admin"
# password: "helloAdmin"database: my_db
各类场景
以Book类,作为演示案例
package com.walker.sample.mongdb.entity;import com.walker.core.BasePage;
import lombok.Data;
import org.springframework.data.annotation.Id;
import org.springframework.data.annotation.Transient;
import org.springframework.data.mongodb.core.mapping.Document;import java.util.List;//文档名称:
@Document(collection = "Books")
@Data
public class Book {// id@Idprivate String id;// 主题private String title;// 作者private String author;// 创建年份private Integer year;// 如果需要忽略的字段,则使用@Transient
}
新增数据
package com.walker.sample.easyexcel;import cn.hutool.core.util.RandomUtil;
import com.walker.sample.mongdb.entity.Book;
import com.walker.sample.mongdb.utils.RandomNameUtil;
import lombok.extern.slf4j.Slf4j;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.data.mongodb.core.MongoTemplate;import java.util.ArrayList;
import java.util.Collections;
import java.util.List;@Slf4j
@SpringBootTest
public class MongdbTest {// 1、引入template依赖@Autowiredprivate MongoTemplate mongoTemplate;/*** author:walker* time: 2024/6/5* description: 插入数据*/@Testpublic void addData(){List<Book> books = new ArrayList<>();Book book;// 2、构建数据for (int i = 0; i < 10000; i++) {book = new Book();book.setTitle(RandomNameUtil.getName()+"的书"+i);book.setAuthor(RandomNameUtil.getName());book.setYear(Integer.parseInt(RandomUtil.randomNumbers(5)));books.add(book);}
// 3、使用insert进行数据的插入mongoTemplate.insert(books,Book.class);}
}
插入数据结果:
但是可以发现,多了一个_class字段
作用:是为了方便处理Pojo中存在继承的情况,增加系统的扩展性的
具体可以参考:
MongoDB中_class字段的作用 - 上帝爱吃苹果-Soochow - 博客园
注意:
- RandomNameUtil类:主要是用来创建名称
package com.walker.sample.mongdb.utils;/*** * 随机姓名**/
public class RandomNameUtil {// 姓氏池private static final String XING = "赵钱孙李周吴郑王";// 名字池private static final String MING = "三四五六七八建国强国富民少年强则中国强";public static String getName() {// 获取姓氏池的随机下标并随机获取一个姓氏char xing = XING.charAt((int) (Math.random() * XING.length()));// 创建一个可扩容字符串StringBuilder userName = new StringBuilder().append(xing);// 随机生成1或2,决定名字长度int mingLength = 1 + (int) (Math.random() * 2);int mingPoolLength = MING.length();for (int i = 0; i < mingLength; i++) {// 获取名字池的随机下标并随机获取一个名字字符并拼接char ming = MING.charAt((int) (Math.random() * mingPoolLength));userName.append(ming);}return userName.toString();}
}
分页查询
这个应该是我们实际应用中应用的比较多的了。
分别有多条件结合查询、排序、分页、总数查询等,那么下边将使用一个查询接口作为案例。
查询controller和逻辑
package com.walker.sample.mongdb;import cn.hutool.core.collection.CollUtil;
import cn.hutool.core.util.StrUtil;
import com.walker.core.TableDataInfo;
import com.walker.mongdb.utils.MyCriteria;
import com.walker.mongdb.utils.MyQuery;
import com.walker.sample.mongdb.entity.Book;
import com.walker.sample.mongdb.entity.BookForm;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.query.Criteria;
import org.springframework.data.mongodb.core.query.Query;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;import java.util.ArrayList;
import java.util.List;@RestController
@RequestMapping("/book")
public class BookController {// 1、引入模板类@Autowiredprivate MongoTemplate mongoTemplate;@GetMapping("/list")public TableDataInfo<Book> list(BookForm form) {// 2、创建查询类Query query = new Query();// 3、创建标准/条件Criteria criteria = new Criteria();// 因为是多条件结合,所以使用数组进行存储List<Criteria> criteriaList = new ArrayList<>();// 模块查询title、if (StrUtil.isNotEmpty(form.getTitle())) {criteriaList.add(MyCriteria.like(Book::getTitle, form.getTitle()));}// 精准查询yearif (form.getYear() != null) {criteriaList.add(MyCriteria.is(Book::getYear, form.getYear()));}// 根据year查询inif (CollUtil.isNotEmpty(form.getYears())) {criteriaList.add(MyCriteria.in(Book::getYear, form.getYears()));}// 将条件放入一个大的criteria中criteria.andOperator(criteriaList);// query添加criteriaquery.addCriteria(criteria);// 计算总数Long count = mongoTemplate.count(query, Book.class);// 设置跳页MyQuery.setPageNumAndSize(query, form.getPageNum(), form.getPageSize());// 排序MyQuery.sortAsc(query, Book::getYear);// 分页查询List<Book> books = mongoTemplate.find(query, Book.class);return new TableDataInfo<>(count, books);}}
涉及类
1、查询参数
用于请求参数的传递
package com.walker.sample.mongdb.entity;import com.walker.core.BasePage;
import lombok.Data;
import org.springframework.data.annotation.Id;
import org.springframework.data.annotation.Transient;
import org.springframework.data.mongodb.core.mapping.Document;import java.util.List;@Data
public class BookForm extends BasePage{
// 主题private String title;
// 作者private String author;
// 创建年份private Integer year;
// 查询的years的条件@Transientprivate List<Integer> years;
}
- 基础分页参数
统一封装,如果需要使用的参数直接继承即可
package com.walker.core;import lombok.Data;@Data
public class BasePage {/*** 页码*/private Integer pageNum;/*** 页数*/private Integer pageSize;}
- Criteria工具类
package com.walker.mongdb.utils;import com.walker.mongdb.annotation.SFunction;
import org.springframework.data.mongodb.core.query.Criteria;public class MyCriteria {/*** 模糊查询*/public static <T> Criteria like(SFunction<T> getField, Object value){String fieldName = FieldUtils.getFieldName(getField);return Criteria.where(fieldName).regex(".*?\\" + value + ".*");}/*** 精确查询*/public static <T> Criteria is(SFunction<T> getField,Object value){String fieldName = FieldUtils.getFieldName(getField);return Criteria.where(fieldName).is(value);}/*** 多个查询*/public static <T> Criteria in(SFunction<T> getField,Object value){String fieldName = FieldUtils.getFieldName(getField);return Criteria.where(fieldName).in(value);}
}
- Query封装类
package com.walker.mongdb.utils;import com.walker.mongdb.annotation.SFunction;
import org.springframework.data.domain.Sort;
import org.springframework.data.mongodb.core.query.Query;public class MyQuery {/*** 设置页码和页数*/public static void setPageNumAndSize(Query query, Integer pageNum, Integer pageSize) {if(pageNum==null) pageNum=1;if(pageSize==null) pageSize=10;query.skip((long) (pageNum - 1) *pageSize);query.limit(pageSize);}/*** 正序*/public static <T> void sortAsc(Query query, SFunction<T> getField) {String fieldName = FieldUtils.getFieldName(getField);Sort sort = Sort.by(Sort.Direction.ASC, fieldName);query.with(sort);}/*** 倒序*/public static <T> void sortDesc(Query query, SFunction<T> getField) {String fieldName = FieldUtils.getFieldName(getField);Sort sort = Sort.by(Sort.Direction.DESC, fieldName);query.with(sort);}
}
- 属性相关类,为了能够使用Stream方法去获取类的名称,减少魔法值的使用
package com.walker.mongdb.utils;import com.walker.mongdb.annotation.SFunction;
import org.springframework.util.ClassUtils;
import org.springframework.util.ReflectionUtils;import java.beans.Introspector;
import java.lang.invoke.SerializedLambda;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;public class FieldUtils {private static final Map<SFunction<?>, Field> FUNCTION_CACHE = new ConcurrentHashMap<>();public static <T> String getFieldName(SFunction<T> function) {Field field = FieldUtils.getField(function);return field.getName();}public static <T> Field getField(SFunction<T> function) {return FUNCTION_CACHE.computeIfAbsent(function, FieldUtils::findField);}public static <T> Field findField(SFunction<T> function) {// 第1步 获取SerializedLambdafinal SerializedLambda serializedLambda = getSerializedLambda(function);// 第2步 implMethodName 即为Field对应的Getter方法名final String implClass = serializedLambda.getImplClass();final String implMethodName = serializedLambda.getImplMethodName();final String fieldName = convertToFieldName(implMethodName);// 第3步 Spring 中的反射工具类获取Class中定义的Fieldfinal Field field = getField(fieldName, serializedLambda);// 第4步 如果没有找到对应的字段应该抛出异常if (field == null) {throw new RuntimeException("No such class 「"+ implClass +"」 field 「" + fieldName + "」.");}return field;}static Field getField(String fieldName, SerializedLambda serializedLambda) {try {// 获取的Class是字符串,并且包名是“/”分割,需要替换成“.”,才能获取到对应的Class对象String declaredClass = serializedLambda.getImplClass().replace("/", ".");Class<?>aClass = Class.forName(declaredClass, false, ClassUtils.getDefaultClassLoader());return ReflectionUtils.findField(aClass, fieldName);}catch (ClassNotFoundException e) {throw new RuntimeException("get class field exception.", e);}}static String convertToFieldName(String getterMethodName) {// 获取方法名String prefix = null;if (getterMethodName.startsWith("get")) {prefix = "get";}else if (getterMethodName.startsWith("is")) {prefix = "is";}if (prefix == null) {throw new IllegalArgumentException("invalid getter method: " + getterMethodName);}// 截取get/is之后的字符串并转换首字母为小写return Introspector.decapitalize(getterMethodName.replace(prefix, ""));}static <T> SerializedLambda getSerializedLambda(SFunction<T> function) {try {Method method = function.getClass().getDeclaredMethod("writeReplace");method.setAccessible(Boolean.TRUE);return (SerializedLambda) method.invoke(function);}catch (Exception e) {throw new RuntimeException("get SerializedLambda exception.", e);}}
}
函数接口
package com.walker.mongdb.annotation;import java.io.Serializable;@FunctionalInterface
public interface SFunction<T> extends Serializable {Object apply(T t);
}
测试
具体就不演示了,可以使用各种参数进行测试
事务
确保你的MongoDB服务器版本至少是4.0以支持事务。此外,在使用事务时,请注意以下几点:
- 你的MongoDB集合必须是事务兼容的。
- 所有参与事务的集合必须在同一个数据库中。
- 在事务方法中,不要直接使用MongoTemplate的execute方法来执行自定义操作。
- 事务方法不能是非事务性的(即不能是@Transactional(propagation = Propagation.NOT_SUPPORTED))。
- 如果使用MongoTemplate进行查询,确保查询是事务兼容的。
实现方案:
1、服务开启事务 使用@EnableTransactionManagement注解
package com.walker.sample;import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.transaction.annotation.EnableTransactionManagement;//开启事务
@EnableTransactionManagement
@SpringBootApplication
public class WalkerSampleApplication {public static void main(String[] args) {SpringApplication.run(WalkerSampleApplication.class, args);}
}
忽略类中的字段
使用@Transient
package com.walker.sample.mongdb;import lombok.Data;
import org.springframework.data.annotation.Id;
import org.springframework.data.annotation.Transient;
import org.springframework.data.mongodb.core.mapping.Document;import java.util.List;//文档名称:
@Document(collection = "Books")
@Data
public class Book {@Idprivate String id;private String title;private String author;private Integer year;@Transientprivate List<Integer> years;
}
参考:
https://blog.csdn.net/weixin_53742691/article/details/132418525