Spring Boot uses Mybatis Plus to query single field data and specified field data

Spring Boot uses Mybatis Plus to query single field data and specified field data

In SpringBoot, we use Myba Plus and usually only need a certain field or a few fields in the query results. Without further ado, just go to the code:

object entity class

@Data
public class Admin implements Serializable {
    
    

    private static final long serialVersionUID = 7406871806983647481L;
    @TableId(value = "admin_id")
    private String adminId;
    private String adminName;
    private String adminMobile;
    private String adminPassword;
}

Use Stream to filter required fields

List<String> collect = adminService.list().stream().map(Admin::getAdminMobile).collect(Collectors.toList());

Use Mybatis Plus to filter the required fields

// 查询单个字段
List<String> strings = adminService.listObjs(new QueryWrapper<Admin>()
                    .lambda().select(Admin::getAdminMobile), Object::toString);
// 查询多个字段，其它不需要查询的字段则为null
List<Object> objects = adminService.listObjs(new QueryWrapper<Admin>()
                    .lambda().select(Admin::getAdminMobile, Admin::getAdminName));