MySQL - 排序规则（latin1_swedish_ci 隐式）和（utf8_general_ci coercible for operation '=' 的非法组合

Question

当我执行下面的查询时，我得到了这个错误：

错误代码：1267。非法混合排序规则 (latin1_swedish_ci,IMPLICIT) 和 (utf8_general_ci,COERCIBLE) 用于操作 '='

如果您需要此代码背后的背景，这里是解释：
MySQL - How Can I Automate a View Query That Subtracts Metrics From the Most Recent Date To The Previous Day & Date Stamps The Most Recent Data

我将“facebook_insight”表排序规则设置为：“utf8_general_ci”，但仍然出现错误。谁能帮帮我？

MySQL 查询：

CREATE VIEW `facebook_insights` AS  
SELECT  
  t1.id  
, t1.timestamp  
, t1.message  
, t1.posted  
, t1.permalink_url  
, t1.caption  
, t1.link  
, t1.type  
, t1.post_impressions - t2.post_impressions as Impressions  
, t1.post_impressions_organic - t2.post_impressions_organic as Post_Impressions_Organic  
, t1.post_impressions_paid - t2.post_impressions_paid as Post_Impressions_Paid  
, t1.post_engaged_users - t2.post_engaged_users as Post_Engaged_Users  
, t1.post_consumptions - t2.post_consumptions as Post_Consumptions  
, t1.post_negative_feedback - t2.post_negative_feedback as 
Post_Negative_Feedback  
, t1.post_negative_feedback_unique - t2.Post_Negative_Feedback_Unique as 
Post_Negative_Feedback_Unique  
, t1.post_impressions_fan - t2.post_impressions_fan as Post_Impressions_Fan  
, t1.post_impressions_fan_paid - t2.post_impressions_fan_paid as 
Post_Impressions_Fan_Paid  
, t1.post_engaged_fan - t2.Post_Engaged_Fan as Post_Engaged_Fan  
, t1.post_video_complete_views_organic - 
t2.post_video_complete_views_organic as Post_Video_Complete_Views_Organic  
, t1.post_video_complete_views_paid - t2.post_video_complete_views_paid as 
Post_Video_Complete_Views_Paid  
, t1.post_video_views_10s - t2.post_video_views_10s as Post_Video_Views_10s  
, t1.post_video_views_10s_unique - t2.post_video_views_10s_unique as 
Post_Video_Views_10s_Unique  
, t1.post_video_views_organic - t2.post_video_views_organic as 
Post_Video_Views_Organic  
, t1.post_video_views_paid - t2.post_video_views_paid as 
Post_Video_Views_Paid  
, t1.post_video_views_clicked_to_play - t2.post_video_views_clicked_to_play 
as Post_Video_Views_Clicked_to_Play  

FROM  
unpaid_media.facebook_insight t1  
JOIN unpaid_media.facebook_insight t2  
ON t1.id = t2.id   
and t1.timestamp  = t2.timestamp + INTERVAL 1 DAY  

Answer 1

我可以从您的related question 中猜到，您的timestamp 列的类型不是date, datetime or timestamp 中的任何一个。可能是varchar 或text。

因此，当您尝试将 INTERVAL 1 DAY 添加到不是时间类型的值时，您会收到错误。

您必须将您的 timestamp 列转换为任何 date, datetime or timestamp 数据类型。

作为一种快速修复，您可以在查询中使用STR_TO_DATE() 函数：

CREATE VIEW `facebook_insights` AS
...
and STR_TO_DATE(t1.timestamp,'%m/%d/%Y') = STR_TO_DATE(t2.timestamp,'%m/%d/%Y') + INTERVAL 1 DAY 

但最好更改您的表以获得正确的数据类型。