bo_reception_process_record表中有process_id，attend，status，people_num字段，现在想根据process_id筛选出来的数据，获取到attend = 2时attend = 1时status = 10时status = 20不同状态下，计算people_num的总数，请帮我写一个sql

好的，以下是根据您的要求写的 SQL 语句：

SELECT 
  SUM(IF(attend = 1 AND status = 10, people_num, 0)) AS attend_1_status_10_num,
  SUM(IF(attend = 1 AND status = 20, people_num, 0)) AS attend_1_status_20_num,
  SUM(IF(attend = 2 AND status = 10, people_num, 0)) AS attend_2_status_10_num,
  SUM(IF(attend = 2 AND status = 20, people_num, 0)) AS attend_2_status_20_num
FROM 
  bo_reception_process_record
WHERE 
  process_id = 'your_process_id' AND attend = 2;

以上 SQL 语句中，使用了 `IF` 函数对 `people_num` 进行了分类求和，分别计算了 `attend = 1` 且 `status = 10`，`attend = 1` 且 `status = 20`，`attend = 2` 且 `status = 10`，`attend = 2` 且 `status = 20` 四种情况下的总人数。同时，增加了 `attend = 2` 的筛选条件。您只需要将 `your_process_id` 替换成您想要筛选的 `process_id` 即可。