MongoTemplate操作mongodb数据库

悠悠 2022-05-08 07:12 540阅读 0赞

## 一、MongoTemplate操作常用的类 ##

Criteria类：它封装所有的语句，以方法的形式进行查询。

Query类：这是将语句进行封装或者添加排序之类的操作。

## 二、Mongodb集合定义案例 ##

import org.springframework.data.mongodb.core.index.Indexed;
    import org.springframework.data.mongodb.core.mapping.Document;
    import org.springframework.data.mongodb.core.mapping.Field;
    
    @Document(collection = "collection_name")
    public class UserPO {
        @Indexed
        @Field("user_id")
        private Long userId;
    
        @Field("username")
        private String username;
    
        @Field("password")
        private String password;
    
        public Long getUserId() {
            return userId;
        }
    
        public void setUserId(Long userId) {
            this.userId = userId;
        }
    
        public String getUsername() {
            return username;
        }
    
        public void setUsername(String username) {
            this.username = username;
        }
    
        public String getPassword() {
            return password;
        }
    
        public void setPassword(String password) {
            this.password = password;
        }
    }

注：

*  @Document 用来表明关联的mongo中的那个collection(类似于表名)
 *  @Indexed 为某个字段建立索引
 *  @Field 声明属性对应的数据库中的哪个字段

## 三、MongoTemplate操作mongodb数据库案例 ##

//插入一条
    UserPO userPO = new UserPO();
    userPO.setUserId(1L);
    userPO.setUsername("username");
    userPO.setPassword("password");
    mongoTemplate.insert(userPO);
    
    //插入多条
    LinkedList<UserPO> pos = Lists.newLinkedList();
    UserPO userPO = new UserPO();
    userPO.setUserId(1L);
    userPO.setUsername("username");
    userPO.setPassword("password");
    pos.add(userPO);//集合中可以放多个
    mongoTemplate.insertAll(pos);
    
    //删除
    Query query=new Query(Criteria.where("_id").is(id));
    mongoTemplate.remove(query,UserPO.class);
    
    //更新
    Query query=new Query(Criteria.where("_id").is(id));
    Update update = Update.update("要更新的字段", "更新的值");
    mongoTemplate.updateFirst(query, update, UserPO.class);
    
    //查找
    //分页查询
    Query query = new Query();
    query.skip("跳过的数据条数").limit("一页的数据条数"); 
    return mongoTemplate.find(query, UserPO.class);
    
    //条件查询1，多条件is("值")后面可以加and("字段2").is("值2")
    Query query=new Query(Criteria.where("字段1").is("值1"));
    return mongoTemplate.find(query, UserPO.class);

参考文献：

[https://docs.spring.io/spring-data/mongodb/docs/current/api/org/springframework/data/mongodb/core/MongoTemplate.html\#executeCommand-org.bson.Document-][https_docs.spring.io_spring-data_mongodb_docs_current_api_org_springframework_data_mongodb_core_MongoTemplate.html_executeCommand-org.bson.Document-]

[https://www.jianshu.com/p/5c4a45f174e9][https_www.jianshu.com_p_5c4a45f174e9]

[https_docs.spring.io_spring-data_mongodb_docs_current_api_org_springframework_data_mongodb_core_MongoTemplate.html_executeCommand-org.bson.Document-]: https://docs.spring.io/spring-data/mongodb/docs/current/api/org/springframework/data/mongodb/core/MongoTemplate.html#executeCommand-org.bson.Document-
[https_www.jianshu.com_p_5c4a45f174e9]: https://www.jianshu.com/p/5c4a45f174e9