Mysql 多字段去重留一，保留时间最晚的一条

1. mysql 多表连接删除

2. 如果出现错误：ERROR 1109 (42S02): Unknown table 'xxx' in MULTI DELETE

   请注意delete 后面，使用表格名称或别名，和from后面显示的表名保持一致

 

DELETE c
FROM
python.basic c, 
(
SELECT
    max(`timestamp`) `timestamp`,
    account_id,
    post_id,
    post_date,
    first_category,
    second_category,
    third_category,
    keyword,
    account_type,
    region_province,
    region_city
FROM
    python.basic
GROUP BY
    third_category,
    brand,
    post_id,
    keyword
HAVING
    count(*) > 1
) t
WHERE
 c.third_category = t.third_category 
 and c.brand = t.brand 
 and c.post_id = t.post_id 
 and c.keyword = t.keyword 
 and c.`timestamp` < t.`timestamp`;