如何进行Mapper多表关联查询

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1、首先写sql语句

select p.id, p.create_time, p.update_time, p.create_user, p.update_user, p.project_name, p.test_user, 
    p.dev_user, p.simple_desc, p.other_desc, p.project_code, p.belong_env_id, p.status_id,u.status_name,u.description from projectinfo_temp p LEFT JOIN usestatus u on p.status_id = u.id

2、关联pojo

@ToString
public class ProjectinfoTemp {

    private Integer id;

    private Date createTime;

    private Date updateTime;

    private String createUser;

    private String updateUser;

    private String projectName;

    private String testUser;

    private String devUser;

    private String simpleDesc;

    private String otherDesc;

    private String projectCode;

    private Integer belongEnvId;

    private Integer statusId;
    /**
     *  关联状态表 激活状态
     */
    private Usestatus usestatus;

状态表

/**
 *
 * @author liwen406
 * @date 2019-04-21 09:12
 */
@ToString
public class Usestatus {
    private Integer id;

    private String statusName;

    private String description;

3编写关联sql语句

模仿写法

<sql id="WithBase_Column_List" >
p.id, p.create_time, p.update_time, p.create_user, p.update_user, p.project_name, p.test_user,
p.dev_user, p.simple_desc, p.other_desc, p.project_code, p.belong_env_id, p.status_id,u.status_name,u.description
</sql>

    select
    
      distinct
    
    
    from projectinfo_temp
    
      
    
    
      order by ${orderByClause}
    
  

  
    select
    
      distinct
    
    
    from projectinfo_temp p LEFT JOIN usestatus u on p.status_id = u.id
    
      
    
    
      order by ${orderByClause}
    
  

4前端调用写法

                                
                                    
                                    
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                                        应用名称
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                                        模块/接口/用例
                                        状态
                                        操作
                                    
                                    
                                    
                                    
                                        
                                        
                                        
                                        
                                        
                                        
                                        
                                            运行
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