MySQL STR_TO_DATE错误为NULL [英] MySQL STR_TO_DATE NULL on error

问题描述

我目前正在将具有VARCHAR列中的日期的表迁移到具有DATE列的新表中.我设法将旧表中的字符串值清除为"YYYY-MM-DD" 格式，但是当我尝试执行插入操作时，日期为"2006-04的错误-31"，因为那个四月只有30天(注册时是拼写错误)，

I'm currently migrating a table with dates in VARCHAR columns to a new table with DATE columns. I managed to sanitize the string values in the old table to the format "YYYY-MM-DD" but when I try to perform the insert I got an error with the date "2006-04-31" because that April only had 30 days (was a typo when it was registered),

我的问题是:当日期无效时如何将列设置为NULL而不会出现错误?我的SQL如下:

My question is: how can I set to NULL the column when the date is invalid without getting an error? My SQL is the following:

INSERT INTO newFancyTable (created_at)
SELECT str_to_date(created, '%Y-%m-%d') FROM oldCrappyTable;

错误如下:

Error Code: 1292. Incorrect date value: '2006-04-31' for column 'created_at' at row 1

谢谢

更新

我也尝试使用以下方法:

I also tried using the following approach:

INSERT INTO newFancyTable (created_at)
SELECT CAST(created AS DATE) FROM oldCrappyTable;

出现相同的错误，并尝试更新oldCrappyTable会返回相同的结果:

With the same error, and trying to update the oldCrappyTable would return the same:

UPDATE oldCrappyTable SET created = CAST(created AS DATE);

两次返回:

Error Code: 1292. Incorrect datetime value: '2006-04-31'

更新2

最后，我使用了多个CASE来隔离无效日期，总之它们只有5个， 但是，可以通过执行以下操作来重现该问题:

At last, I used multiple CASEs to isolate that invalid dates, in sum they were only 5 of them, Nevertheless, the issue can be reproduced by doing:

CREATE TABLE dates_temp (
  test_date DATE DEFAULT NULL
) ENGINE=MEMORY;

INSERT INTO dates_temp
SELECT STR_TO_DATE("2006-04-31", '%Y-%m-%d');

DROP TABLE dates_temp;

推荐答案

一个可能的解决方法是关闭严格模式，无论是针对整个服务器，特定会话还是仅针对少数语句.例如:

A possible workaround is to turn off strict mode, either for the whole server, for a particular session, or for just a few statements. For example:

 set @old_sql_mode = @@sql_mode; 
 set sql_mode = ''; 
 -- Run some statements which may result in error
 set sql_mode = @old_sql_mode;

其他信息

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